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Diffstat (limited to 'arch/tile/include/gxio/mpipe.h')
| -rw-r--r-- | arch/tile/include/gxio/mpipe.h | 1871 |
1 files changed, 0 insertions, 1871 deletions
diff --git a/arch/tile/include/gxio/mpipe.h b/arch/tile/include/gxio/mpipe.h deleted file mode 100644 index 73e83a187866..000000000000 --- a/arch/tile/include/gxio/mpipe.h +++ /dev/null @@ -1,1871 +0,0 @@ -/* - * Copyright 2012 Tilera Corporation. All Rights Reserved. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation, version 2. - * - * This program is distributed in the hope that it will be useful, but - * WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or - * NON INFRINGEMENT. See the GNU General Public License for - * more details. - */ - -#ifndef _GXIO_MPIPE_H_ -#define _GXIO_MPIPE_H_ - -/* - * - * An API for allocating, configuring, and manipulating mPIPE hardware - * resources. - */ - -#include <gxio/common.h> -#include <gxio/dma_queue.h> - -#include <linux/time.h> - -#include <arch/mpipe_def.h> -#include <arch/mpipe_shm.h> - -#include <hv/drv_mpipe_intf.h> -#include <hv/iorpc.h> - -/* - * - * The TILE-Gx mPIPE&tm; shim provides Ethernet connectivity, packet - * classification, and packet load balancing services. The - * gxio_mpipe_ API, declared in <gxio/mpipe.h>, allows applications to - * allocate mPIPE IO channels, configure packet distribution - * parameters, and send and receive Ethernet packets. The API is - * designed to be a minimal wrapper around the mPIPE hardware, making - * system calls only where necessary to preserve inter-process - * protection guarantees. - * - * The APIs described below allow the programmer to allocate and - * configure mPIPE resources. As described below, the mPIPE is a - * single shared hardware device that provides partitionable resources - * that are shared between all applications in the system. The - * gxio_mpipe_ API allows userspace code to make resource request - * calls to the hypervisor, which in turns keeps track of the - * resources in use by all applications, maintains protection - * guarantees, and resets resources upon application shutdown. - * - * We strongly recommend reading the mPIPE section of the IO Device - * Guide (UG404) before working with this API. Most functions in the - * gxio_mpipe_ API are directly analogous to hardware interfaces and - * the documentation assumes that the reader understands those - * hardware interfaces. - * - * @section mpipe__ingress mPIPE Ingress Hardware Resources - * - * The mPIPE ingress hardware provides extensive hardware offload for - * tasks like packet header parsing, load balancing, and memory - * management. This section provides a brief introduction to the - * hardware components and the gxio_mpipe_ calls used to manage them; - * see the IO Device Guide for a much more detailed description of the - * mPIPE's capabilities. - * - * When a packet arrives at one of the mPIPE's Ethernet MACs, it is - * assigned a channel number indicating which MAC received it. It - * then proceeds through the following hardware pipeline: - * - * @subsection mpipe__classification Classification - * - * A set of classification processors run header parsing code on each - * incoming packet, extracting information including the destination - * MAC address, VLAN, Ethernet type, and five-tuple hash. Some of - * this information is then used to choose which buffer stack will be - * used to hold the packet, and which bucket will be used by the load - * balancer to determine which application will receive the packet. - * - * The rules by which the buffer stack and bucket are chosen can be - * configured via the @ref gxio_mpipe_classifier API. A given app can - * specify multiple rules, each one specifying a bucket range, and a - * set of buffer stacks, to be used for packets matching the rule. - * Each rule can optionally specify a restricted set of channels, - * VLANs, and/or dMACs, in which it is interested. By default, a - * given rule starts out matching all channels associated with the - * mPIPE context's set of open links; all VLANs; and all dMACs. - * Subsequent restrictions can then be added. - * - * @subsection mpipe__load_balancing Load Balancing - * - * The mPIPE load balancer is responsible for choosing the NotifRing - * to which the packet will be delivered. This decision is based on - * the bucket number indicated by the classification program. In - * general, the bucket number is based on some number of low bits of - * the packet's flow hash (applications that aren't interested in flow - * hashing use a single bucket). Each load balancer bucket keeps a - * record of the NotifRing to which packets directed to that bucket - * are currently being delivered. Based on the bucket's load - * balancing mode (@ref gxio_mpipe_bucket_mode_t), the load balancer - * either forwards the packet to the previously assigned NotifRing or - * decides to choose a new NotifRing. If a new NotifRing is required, - * the load balancer chooses the least loaded ring in the NotifGroup - * associated with the bucket. - * - * The load balancer is a shared resource. Each application needs to - * explicitly allocate NotifRings, NotifGroups, and buckets, using - * gxio_mpipe_alloc_notif_rings(), gxio_mpipe_alloc_notif_groups(), - * and gxio_mpipe_alloc_buckets(). Then the application needs to - * configure them using gxio_mpipe_init_notif_ring() and - * gxio_mpipe_init_notif_group_and_buckets(). - * - * @subsection mpipe__buffers Buffer Selection and Packet Delivery - * - * Once the load balancer has chosen the destination NotifRing, the - * mPIPE DMA engine pops at least one buffer off of the 'buffer stack' - * chosen by the classification program and DMAs the packet data into - * that buffer. Each buffer stack provides a hardware-accelerated - * stack of data buffers with the same size. If the packet data is - * larger than the buffers provided by the chosen buffer stack, the - * mPIPE hardware pops off multiple buffers and chains the packet data - * through a multi-buffer linked list. Once the packet data is - * delivered to the buffer(s), the mPIPE hardware writes the - * ::gxio_mpipe_idesc_t metadata object (calculated by the classifier) - * into the NotifRing and increments the number of packets delivered - * to that ring. - * - * Applications can push buffers onto a buffer stack by calling - * gxio_mpipe_push_buffer() or by egressing a packet with the - * ::gxio_mpipe_edesc_t::hwb bit set, indicating that the egressed - * buffers should be returned to the stack. - * - * Applications can allocate and initialize buffer stacks with the - * gxio_mpipe_alloc_buffer_stacks() and gxio_mpipe_init_buffer_stack() - * APIs. - * - * The application must also register the memory pages that will hold - * packets. This requires calling gxio_mpipe_register_page() for each - * memory page that will hold packets allocated by the application for - * a given buffer stack. Since each buffer stack is limited to 16 - * registered pages, it may be necessary to use huge pages, or even - * extremely huge pages, to hold all the buffers. - * - * @subsection mpipe__iqueue NotifRings - * - * Each NotifRing is a region of shared memory, allocated by the - * application, to which the mPIPE delivers packet descriptors - * (::gxio_mpipe_idesc_t). The application can allocate them via - * gxio_mpipe_alloc_notif_rings(). The application can then either - * explicitly initialize them with gxio_mpipe_init_notif_ring() and - * then read from them manually, or can make use of the convenience - * wrappers provided by @ref gxio_mpipe_wrappers. - * - * @section mpipe__egress mPIPE Egress Hardware - * - * Applications use eDMA rings to queue packets for egress. The - * application can allocate them via gxio_mpipe_alloc_edma_rings(). - * The application can then either explicitly initialize them with - * gxio_mpipe_init_edma_ring() and then write to them manually, or - * can make use of the convenience wrappers provided by - * @ref gxio_mpipe_wrappers. - * - * @section gxio__shortcomings Plans for Future API Revisions - * - * The API defined here is only an initial version of the mPIPE API. - * Future plans include: - * - * - Higher level wrapper functions to provide common initialization - * patterns. This should help users start writing mPIPE programs - * without having to learn the details of the hardware. - * - * - Support for reset and deallocation of resources, including - * cleanup upon application shutdown. - * - * - Support for calling these APIs in the BME. - * - * - Support for IO interrupts. - * - * - Clearer definitions of thread safety guarantees. - * - * @section gxio__mpipe_examples Examples - * - * See the following mPIPE example programs for more information about - * allocating mPIPE resources and using them in real applications: - * - * - @ref mpipe/ingress/app.c : Receiving packets. - * - * - @ref mpipe/forward/app.c : Forwarding packets. - * - * Note that there are several more examples. - */ - -/* Flags that can be passed to resource allocation functions. */ -enum gxio_mpipe_alloc_flags_e { - /* Require an allocation to start at a specified resource index. */ - GXIO_MPIPE_ALLOC_FIXED = HV_MPIPE_ALLOC_FIXED, -}; - -/* Flags that can be passed to memory registration functions. */ -enum gxio_mpipe_mem_flags_e { - /* Do not fill L3 when writing, and invalidate lines upon egress. */ - GXIO_MPIPE_MEM_FLAG_NT_HINT = IORPC_MEM_BUFFER_FLAG_NT_HINT, - - /* L3 cache fills should only populate IO cache ways. */ - GXIO_MPIPE_MEM_FLAG_IO_PIN = IORPC_MEM_BUFFER_FLAG_IO_PIN, -}; - -/* An ingress packet descriptor. When a packet arrives, the mPIPE - * hardware generates this structure and writes it into a NotifRing. - */ -typedef MPIPE_PDESC_t gxio_mpipe_idesc_t; - -/* An egress command descriptor. Applications write this structure - * into eDMA rings and the hardware performs the indicated operation - * (normally involving egressing some bytes). Note that egressing a - * single packet may involve multiple egress command descriptors. - */ -typedef MPIPE_EDMA_DESC_t gxio_mpipe_edesc_t; - -/* - * Max # of mpipe instances. 2 currently. - */ -#define GXIO_MPIPE_INSTANCE_MAX HV_MPIPE_INSTANCE_MAX - -#define NR_MPIPE_MAX GXIO_MPIPE_INSTANCE_MAX - -/* Get the "va" field from an "idesc". - * - * This is the address at which the ingress hardware copied the first - * byte of the packet. - * - * If the classifier detected a custom header, then this will point to - * the custom header, and gxio_mpipe_idesc_get_l2_start() will point - * to the actual L2 header. - * - * Note that this value may be misleading if "idesc->be" is set. - * - * @param idesc An ingress packet descriptor. - */ -static inline unsigned char *gxio_mpipe_idesc_get_va(gxio_mpipe_idesc_t *idesc) -{ - return (unsigned char *)(long)idesc->va; -} - -/* Get the "xfer_size" from an "idesc". - * - * This is the actual number of packet bytes transferred into memory - * by the hardware. - * - * Note that this value may be misleading if "idesc->be" is set. - * - * @param idesc An ingress packet descriptor. - * - * ISSUE: Is this the best name for this? - * FIXME: Add more docs about chaining, clipping, etc. - */ -static inline unsigned int gxio_mpipe_idesc_get_xfer_size(gxio_mpipe_idesc_t - *idesc) -{ - return idesc->l2_size; -} - -/* Get the "l2_offset" from an "idesc". - * - * Extremely customized classifiers might not support this function. - * - * This is the number of bytes between the "va" and the L2 header. - * - * The L2 header consists of a destination mac address, a source mac - * address, and an initial ethertype. Various initial ethertypes - * allow encoding extra information in the L2 header, often including - * a vlan, and/or a new ethertype. - * - * Note that the "l2_offset" will be non-zero if (and only if) the - * classifier processed a custom header for the packet. - * - * @param idesc An ingress packet descriptor. - */ -static inline uint8_t gxio_mpipe_idesc_get_l2_offset(gxio_mpipe_idesc_t *idesc) -{ - return (idesc->custom1 >> 32) & 0xFF; -} - -/* Get the "l2_start" from an "idesc". - * - * This is simply gxio_mpipe_idesc_get_va() plus - * gxio_mpipe_idesc_get_l2_offset(). - * - * @param idesc An ingress packet descriptor. - */ -static inline unsigned char *gxio_mpipe_idesc_get_l2_start(gxio_mpipe_idesc_t - *idesc) -{ - unsigned char *va = gxio_mpipe_idesc_get_va(idesc); - return va + gxio_mpipe_idesc_get_l2_offset(idesc); -} - -/* Get the "l2_length" from an "idesc". - * - * This is simply gxio_mpipe_idesc_get_xfer_size() minus - * gxio_mpipe_idesc_get_l2_offset(). - * - * @param idesc An ingress packet descriptor. - */ -static inline unsigned int gxio_mpipe_idesc_get_l2_length(gxio_mpipe_idesc_t - *idesc) -{ - unsigned int xfer_size = idesc->l2_size; - return xfer_size - gxio_mpipe_idesc_get_l2_offset(idesc); -} - -/* A context object used to manage mPIPE hardware resources. */ -typedef struct { - - /* File descriptor for calling up to Linux (and thus the HV). */ - int fd; - - /* Corresponding mpipe instance #. */ - int instance; - - /* The VA at which configuration registers are mapped. */ - char *mmio_cfg_base; - - /* The VA at which IDMA, EDMA, and buffer manager are mapped. */ - char *mmio_fast_base; - - /* The "initialized" buffer stacks. */ - gxio_mpipe_rules_stacks_t __stacks; - -} gxio_mpipe_context_t; - -/* This is only used internally, but it's most easily made visible here. */ -typedef gxio_mpipe_context_t gxio_mpipe_info_context_t; - -/* Initialize an mPIPE context. - * - * This function allocates an mPIPE "service domain" and maps the MMIO - * registers into the caller's VA space. - * - * @param context Context object to be initialized. - * @param mpipe_instance Instance number of mPIPE shim to be controlled via - * context. - */ -extern int gxio_mpipe_init(gxio_mpipe_context_t *context, - unsigned int mpipe_instance); - -/* Destroy an mPIPE context. - * - * This function frees the mPIPE "service domain" and unmaps the MMIO - * registers from the caller's VA space. - * - * If a user process exits without calling this routine, the kernel - * will destroy the mPIPE context as part of process teardown. - * - * @param context Context object to be destroyed. - */ -extern int gxio_mpipe_destroy(gxio_mpipe_context_t *context); - -/***************************************************************** - * Buffer Stacks * - ******************************************************************/ - -/* Allocate a set of buffer stacks. - * - * The return value is NOT interesting if count is zero. - * - * @param context An initialized mPIPE context. - * @param count Number of stacks required. - * @param first Index of first stack if ::GXIO_MPIPE_ALLOC_FIXED flag is set, - * otherwise ignored. - * @param flags Flag bits from ::gxio_mpipe_alloc_flags_e. - * @return Index of first allocated buffer stack, or - * ::GXIO_MPIPE_ERR_NO_BUFFER_STACK if allocation failed. - */ -extern int gxio_mpipe_alloc_buffer_stacks(gxio_mpipe_context_t *context, - unsigned int count, - unsigned int first, - unsigned int flags); - -/* Enum codes for buffer sizes supported by mPIPE. */ -typedef enum { - /* 128 byte packet data buffer. */ - GXIO_MPIPE_BUFFER_SIZE_128 = MPIPE_BSM_INIT_DAT_1__SIZE_VAL_BSZ_128, - /* 256 byte packet data buffer. */ - GXIO_MPIPE_BUFFER_SIZE_256 = MPIPE_BSM_INIT_DAT_1__SIZE_VAL_BSZ_256, - /* 512 byte packet data buffer. */ - GXIO_MPIPE_BUFFER_SIZE_512 = MPIPE_BSM_INIT_DAT_1__SIZE_VAL_BSZ_512, - /* 1024 byte packet data buffer. */ - GXIO_MPIPE_BUFFER_SIZE_1024 = MPIPE_BSM_INIT_DAT_1__SIZE_VAL_BSZ_1024, - /* 1664 byte packet data buffer. */ - GXIO_MPIPE_BUFFER_SIZE_1664 = MPIPE_BSM_INIT_DAT_1__SIZE_VAL_BSZ_1664, - /* 4096 byte packet data buffer. */ - GXIO_MPIPE_BUFFER_SIZE_4096 = MPIPE_BSM_INIT_DAT_1__SIZE_VAL_BSZ_4096, - /* 10368 byte packet data buffer. */ - GXIO_MPIPE_BUFFER_SIZE_10368 = - MPIPE_BSM_INIT_DAT_1__SIZE_VAL_BSZ_10368, - /* 16384 byte packet data buffer. */ - GXIO_MPIPE_BUFFER_SIZE_16384 = MPIPE_BSM_INIT_DAT_1__SIZE_VAL_BSZ_16384 -} gxio_mpipe_buffer_size_enum_t; - -/* Convert a buffer size in bytes into a buffer size enum. */ -extern gxio_mpipe_buffer_size_enum_t -gxio_mpipe_buffer_size_to_buffer_size_enum(size_t size); - -/* Convert a buffer size enum into a buffer size in bytes. */ -extern size_t -gxio_mpipe_buffer_size_enum_to_buffer_size(gxio_mpipe_buffer_size_enum_t - buffer_size_enum); - -/* Calculate the number of bytes required to store a given number of - * buffers in the memory registered with a buffer stack via - * gxio_mpipe_init_buffer_stack(). - */ -extern size_t gxio_mpipe_calc_buffer_stack_bytes(unsigned long buffers); - -/* Initialize a buffer stack. This function binds a region of memory - * to be used by the hardware for storing buffer addresses pushed via - * gxio_mpipe_push_buffer() or as the result of sending a buffer out - * the egress with the 'push to stack when done' bit set. Once this - * function returns, the memory region's contents may be arbitrarily - * modified by the hardware at any time and software should not access - * the memory region again. - * - * @param context An initialized mPIPE context. - * @param stack The buffer stack index. - * @param buffer_size_enum The size of each buffer in the buffer stack, - * as an enum. - * @param mem The address of the buffer stack. This memory must be - * physically contiguous and aligned to a 64kB boundary. - * @param mem_size The size of the buffer stack, in bytes. - * @param mem_flags ::gxio_mpipe_mem_flags_e memory flags. - * @return Zero on success, ::GXIO_MPIPE_ERR_INVAL_BUFFER_SIZE if - * buffer_size_enum is invalid, ::GXIO_MPIPE_ERR_BAD_BUFFER_STACK if - * stack has not been allocated. - */ -extern int gxio_mpipe_init_buffer_stack(gxio_mpipe_context_t *context, - unsigned int stack, - gxio_mpipe_buffer_size_enum_t - buffer_size_enum, void *mem, - size_t mem_size, - unsigned int mem_flags); - -/* Push a buffer onto a previously initialized buffer stack. - * - * The size of the buffer being pushed must match the size that was - * registered with gxio_mpipe_init_buffer_stack(). All packet buffer - * addresses are 128-byte aligned; the low 7 bits of the specified - * buffer address will be ignored. - * - * @param context An initialized mPIPE context. - * @param stack The buffer stack index. - * @param buffer The buffer (the low seven bits are ignored). - */ -static inline void gxio_mpipe_push_buffer(gxio_mpipe_context_t *context, - unsigned int stack, void *buffer) -{ - MPIPE_BSM_REGION_ADDR_t offset = { {0} }; - MPIPE_BSM_REGION_VAL_t val = { {0} }; - - /* - * The mmio_fast_base region starts at the IDMA region, so subtract - * off that initial offset. - */ - offset.region = - MPIPE_MMIO_ADDR__REGION_VAL_BSM - - MPIPE_MMIO_ADDR__REGION_VAL_IDMA; - offset.stack = stack; - -#if __SIZEOF_POINTER__ == 4 - val.va = ((ulong) buffer) >> MPIPE_BSM_REGION_VAL__VA_SHIFT; -#else - val.va = ((long)buffer) >> MPIPE_BSM_REGION_VAL__VA_SHIFT; -#endif - - __gxio_mmio_write(context->mmio_fast_base + offset.word, val.word); -} - -/* Pop a buffer off of a previously initialized buffer stack. - * - * @param context An initialized mPIPE context. - * @param stack The buffer stack index. - * @return The buffer, or NULL if the stack is empty. - */ -static inline void *gxio_mpipe_pop_buffer(gxio_mpipe_context_t *context, - unsigned int stack) -{ - MPIPE_BSM_REGION_ADDR_t offset = { {0} }; - - /* - * The mmio_fast_base region starts at the IDMA region, so subtract - * off that initial offset. - */ - offset.region = - MPIPE_MMIO_ADDR__REGION_VAL_BSM - - MPIPE_MMIO_ADDR__REGION_VAL_IDMA; - offset.stack = stack; - - while (1) { - /* - * Case 1: val.c == ..._UNCHAINED, va is non-zero. - * Case 2: val.c == ..._INVALID, va is zero. - * Case 3: val.c == ..._NOT_RDY, va is zero. - */ - MPIPE_BSM_REGION_VAL_t val; - val.word = - __gxio_mmio_read(context->mmio_fast_base + - offset.word); - - /* - * Handle case 1 and 2 by returning the buffer (or NULL). - * Handle case 3 by waiting for the prefetch buffer to refill. - */ - if (val.c != MPIPE_EDMA_DESC_WORD1__C_VAL_NOT_RDY) - return (void *)((unsigned long)val. - va << MPIPE_BSM_REGION_VAL__VA_SHIFT); - } -} - -/***************************************************************** - * NotifRings * - ******************************************************************/ - -/* Allocate a set of NotifRings. - * - * The return value is NOT interesting if count is zero. - * - * Note that NotifRings are allocated in chunks, so allocating one at - * a time is much less efficient than allocating several at once. - * - * @param context An initialized mPIPE context. - * @param count Number of NotifRings required. - * @param first Index of first NotifRing if ::GXIO_MPIPE_ALLOC_FIXED flag - * is set, otherwise ignored. - * @param flags Flag bits from ::gxio_mpipe_alloc_flags_e. - * @return Index of first allocated buffer NotifRing, or - * ::GXIO_MPIPE_ERR_NO_NOTIF_RING if allocation failed. - */ -extern int gxio_mpipe_alloc_notif_rings(gxio_mpipe_context_t *context, - unsigned int count, unsigned int first, - unsigned int flags); - -/* Initialize a NotifRing, using the given memory and size. - * - * @param context An initialized mPIPE context. - * @param ring The NotifRing index. - * @param mem A physically contiguous region of memory to be filled - * with a ring of ::gxio_mpipe_idesc_t structures. - * @param mem_size Number of bytes in the ring. Must be 128, 512, - * 2048, or 65536 * sizeof(gxio_mpipe_idesc_t). - * @param mem_flags ::gxio_mpipe_mem_flags_e memory flags. - * - * @return 0 on success, ::GXIO_MPIPE_ERR_BAD_NOTIF_RING or - * ::GXIO_ERR_INVAL_MEMORY_SIZE on failure. - */ -extern int gxio_mpipe_init_notif_ring(gxio_mpipe_context_t *context, - unsigned int ring, - void *mem, size_t mem_size, - unsigned int mem_flags); - -/* Configure an interrupt to be sent to a tile on incoming NotifRing - * traffic. Once an interrupt is sent for a particular ring, no more - * will be sent until gxio_mica_enable_notif_ring_interrupt() is called. - * - * @param context An initialized mPIPE context. - * @param x X coordinate of interrupt target tile. - * @param y Y coordinate of interrupt target tile. - * @param i Index of the IPI register which will receive the interrupt. - * @param e Specific event which will be set in the target IPI register when - * the interrupt occurs. - * @param ring The NotifRing index. - * @return Zero on success, GXIO_ERR_INVAL if params are out of range. - */ -extern int gxio_mpipe_request_notif_ring_interrupt(gxio_mpipe_context_t - *context, int x, int y, - int i, int e, - unsigned int ring); - -/* Enable an interrupt on incoming NotifRing traffic. - * - * @param context An initialized mPIPE context. - * @param ring The NotifRing index. - * @return Zero on success, GXIO_ERR_INVAL if params are out of range. - */ -extern int gxio_mpipe_enable_notif_ring_interrupt(gxio_mpipe_context_t - *context, unsigned int ring); - -/* Map all of a client's memory via the given IOTLB. - * @param context An initialized mPIPE context. - * @param iotlb IOTLB index. - * @param pte Page table entry. - * @param flags Flags. - * @return Zero on success, or a negative error code. - */ -extern int gxio_mpipe_register_client_memory(gxio_mpipe_context_t *context, - unsigned int iotlb, HV_PTE pte, - unsigned int flags); - -/***************************************************************** - * Notif Groups * - ******************************************************************/ - -/* Allocate a set of NotifGroups. - * - * The return value is NOT interesting if count is zero. - * - * @param context An initialized mPIPE context. - * @param count Number of NotifGroups required. - * @param first Index of first NotifGroup if ::GXIO_MPIPE_ALLOC_FIXED flag - * is set, otherwise ignored. - * @param flags Flag bits from ::gxio_mpipe_alloc_flags_e. - * @return Index of first allocated buffer NotifGroup, or - * ::GXIO_MPIPE_ERR_NO_NOTIF_GROUP if allocation failed. - */ -extern int gxio_mpipe_alloc_notif_groups(gxio_mpipe_context_t *context, - unsigned int count, - unsigned int first, - unsigned int flags); - -/* Add a NotifRing to a NotifGroup. This only sets a bit in the - * application's 'group' object; the hardware NotifGroup can be - * initialized by passing 'group' to gxio_mpipe_init_notif_group() or - * gxio_mpipe_init_notif_group_and_buckets(). - */ -static inline void -gxio_mpipe_notif_group_add_ring(gxio_mpipe_notif_group_bits_t *bits, int ring) -{ - bits->ring_mask[ring / 64] |= (1ull << (ring % 64)); -} - -/* Set a particular NotifGroup bitmask. Since the load balancer - * makes decisions based on both bucket and NotifGroup state, most - * applications should use gxio_mpipe_init_notif_group_and_buckets() - * rather than using this function to configure just a NotifGroup. - */ -extern int gxio_mpipe_init_notif_group(gxio_mpipe_context_t *context, - unsigned int group, - gxio_mpipe_notif_group_bits_t bits); - -/***************************************************************** - * Load Balancer * - ******************************************************************/ - -/* Allocate a set of load balancer buckets. - * - * The return value is NOT interesting if count is zero. - * - * Note that buckets are allocated in chunks, so allocating one at - * a time is much less efficient than allocating several at once. - * - * Note that the buckets are actually divided into two sub-ranges, of - * different sizes, and different chunk sizes, and the range you get - * by default is determined by the size of the request. Allocations - * cannot span the two sub-ranges. - * - * @param context An initialized mPIPE context. - * @param count Number of buckets required. - * @param first Index of first bucket if ::GXIO_MPIPE_ALLOC_FIXED flag is set, - * otherwise ignored. - * @param flags Flag bits from ::gxio_mpipe_alloc_flags_e. - * @return Index of first allocated buffer bucket, or - * ::GXIO_MPIPE_ERR_NO_BUCKET if allocation failed. - */ -extern int gxio_mpipe_alloc_buckets(gxio_mpipe_context_t *context, - unsigned int count, unsigned int first, - unsigned int flags); - -/* The legal modes for gxio_mpipe_bucket_info_t and - * gxio_mpipe_init_notif_group_and_buckets(). - * - * All modes except ::GXIO_MPIPE_BUCKET_ROUND_ROBIN expect that the user - * will allocate a power-of-two number of buckets and initialize them - * to the same mode. The classifier program then uses the appropriate - * number of low bits from the incoming packet's flow hash to choose a - * load balancer bucket. Based on that bucket's load balancing mode, - * reference count, and currently active NotifRing, the load balancer - * chooses the NotifRing to which the packet will be delivered. - */ -typedef enum { - /* All packets for a bucket go to the same NotifRing unless the - * NotifRing gets full, in which case packets will be dropped. If - * the bucket reference count ever reaches zero, a new NotifRing may - * be chosen. - */ - GXIO_MPIPE_BUCKET_DYNAMIC_FLOW_AFFINITY = - MPIPE_LBL_INIT_DAT_BSTS_TBL__MODE_VAL_DFA, - - /* All packets for a bucket always go to the same NotifRing. - */ - GXIO_MPIPE_BUCKET_STATIC_FLOW_AFFINITY = - MPIPE_LBL_INIT_DAT_BSTS_TBL__MODE_VAL_FIXED, - - /* All packets for a bucket go to the least full NotifRing in the - * group, providing load balancing round robin behavior. - */ - GXIO_MPIPE_BUCKET_ROUND_ROBIN = - MPIPE_LBL_INIT_DAT_BSTS_TBL__MODE_VAL_ALWAYS_PICK, - - /* All packets for a bucket go to the same NotifRing unless the - * NotifRing gets full, at which point the bucket starts using the - * least full NotifRing in the group. If all NotifRings in the - * group are full, packets will be dropped. - */ - GXIO_MPIPE_BUCKET_STICKY_FLOW_LOCALITY = - MPIPE_LBL_INIT_DAT_BSTS_TBL__MODE_VAL_STICKY, - - /* All packets for a bucket go to the same NotifRing unless the - * NotifRing gets full, or a random timer fires, at which point the - * bucket starts using the least full NotifRing in the group. If - * all NotifRings in the group are full, packets will be dropped. - * WARNING: This mode is BROKEN on chips with fewer than 64 tiles. - */ - GXIO_MPIPE_BUCKET_PREFER_FLOW_LOCALITY = - MPIPE_LBL_INIT_DAT_BSTS_TBL__MODE_VAL_STICKY_RAND, - -} gxio_mpipe_bucket_mode_t; - -/* Copy a set of bucket initialization values into the mPIPE - * hardware. Since the load balancer makes decisions based on both - * bucket and NotifGroup state, most applications should use - * gxio_mpipe_init_notif_group_and_buckets() rather than using this - * function to configure a single bucket. - * - * @param context An initialized mPIPE context. - * @param bucket Bucket index to be initialized. - * @param bucket_info Initial reference count, NotifRing index, and mode. - * @return 0 on success, ::GXIO_MPIPE_ERR_BAD_BUCKET on failure. - */ -extern int gxio_mpipe_init_bucket(gxio_mpipe_context_t *context, - unsigned int bucket, - gxio_mpipe_bucket_info_t bucket_info); - -/* Initializes a group and range of buckets and range of rings such - * that the load balancer runs a particular load balancing function. - * - * First, the group is initialized with the given rings. - * - * Second, each bucket is initialized with the mode and group, and a - * ring chosen round-robin from the given rings. - * - * Normally, the classifier picks a bucket, and then the load balancer - * picks a ring, based on the bucket's mode, group, and current ring, - * possibly updating the bucket's ring. - * - * @param context An initialized mPIPE context. - * @param group The group. - * @param ring The first ring. - * @param num_rings The number of rings. - * @param bucket The first bucket. - * @param num_buckets The number of buckets. - * @param mode The load balancing mode. - * - * @return 0 on success, ::GXIO_MPIPE_ERR_BAD_BUCKET, - * ::GXIO_MPIPE_ERR_BAD_NOTIF_GROUP, or - * ::GXIO_MPIPE_ERR_BAD_NOTIF_RING on failure. - */ -extern int gxio_mpipe_init_notif_group_and_buckets(gxio_mpipe_context_t - *context, - unsigned int group, - unsigned int ring, - unsigned int num_rings, - unsigned int bucket, - unsigned int num_buckets, - gxio_mpipe_bucket_mode_t - mode); - -/* Return credits to a NotifRing and/or bucket. - * - * @param context An initialized mPIPE context. - * @param ring The NotifRing index, or -1. - * @param bucket The bucket, or -1. - * @param count The number of credits to return. - */ -static inline void gxio_mpipe_credit(gxio_mpipe_context_t *context, - int ring, int bucket, unsigned int count) -{ - /* NOTE: Fancy struct initialization would break "C89" header test. */ - - MPIPE_IDMA_RELEASE_REGION_ADDR_t offset = { {0} }; - MPIPE_IDMA_RELEASE_REGION_VAL_t val = { {0} }; - - /* - * The mmio_fast_base region starts at the IDMA region, so subtract - * off that initial offset. - */ - offset.region = - MPIPE_MMIO_ADDR__REGION_VAL_IDMA - - MPIPE_MMIO_ADDR__REGION_VAL_IDMA; - offset.ring = ring; - offset.bucket = bucket; - offset.ring_enable = (ring >= 0); - offset.bucket_enable = (bucket >= 0); - val.count = count; - - __gxio_mmio_write(context->mmio_fast_base + offset.word, val.word); -} - -/***************************************************************** - * Egress Rings * - ******************************************************************/ - -/* Allocate a set of eDMA rings. - * - * The return value is NOT interesting if count is zero. - * - * @param context An initialized mPIPE context. - * @param count Number of eDMA rings required. - * @param first Index of first eDMA ring if ::GXIO_MPIPE_ALLOC_FIXED flag - * is set, otherwise ignored. - * @param flags Flag bits from ::gxio_mpipe_alloc_flags_e. - * @return Index of first allocated buffer eDMA ring, or - * ::GXIO_MPIPE_ERR_NO_EDMA_RING if allocation failed. - */ -extern int gxio_mpipe_alloc_edma_rings(gxio_mpipe_context_t *context, - unsigned int count, unsigned int first, - unsigned int flags); - -/* Initialize an eDMA ring, using the given memory and size. - * - * @param context An initialized mPIPE context. - * @param ering The eDMA ring index. - * @param channel The channel to use. This must be one of the channels - * associated with the context's set of open links. - * @param mem A physically contiguous region of memory to be filled - * with a ring of ::gxio_mpipe_edesc_t structures. - * @param mem_size Number of bytes in the ring. Must be 512, 2048, - * 8192 or 65536, times 16 (i.e. sizeof(gxio_mpipe_edesc_t)). - * @param mem_flags ::gxio_mpipe_mem_flags_e memory flags. - * - * @return 0 on success, ::GXIO_MPIPE_ERR_BAD_EDMA_RING or - * ::GXIO_ERR_INVAL_MEMORY_SIZE on failure. - */ -extern int gxio_mpipe_init_edma_ring(gxio_mpipe_context_t *context, - unsigned int ering, unsigned int channel, - void *mem, size_t mem_size, - unsigned int mem_flags); - -/* Set the "max_blks", "min_snf_blks", and "db" fields of - * ::MPIPE_EDMA_RG_INIT_DAT_THRESH_t for a given edma ring. - * - * The global pool of dynamic blocks will be automatically adjusted. - * - * This function should not be called after any egress has been done - * on the edma ring. - * - * Most applications should just use gxio_mpipe_equeue_set_snf_size(). - * - * @param context An initialized mPIPE context. - * @param ering The eDMA ring index. - * @param max_blks The number of blocks to dedicate to the ring - * (normally min_snf_blks + 1). Must be greater than min_snf_blocks. - * @param min_snf_blks The number of blocks which must be stored - * prior to starting to send the packet (normally 12). - * @param db Whether to allow use of dynamic blocks by the ring - * (normally 1). - * - * @return 0 on success, negative on error. - */ -extern int gxio_mpipe_config_edma_ring_blks(gxio_mpipe_context_t *context, - unsigned int ering, - unsigned int max_blks, - unsigned int min_snf_blks, - unsigned int db); - -/***************************************************************** - * Classifier Program * - ******************************************************************/ - -/* - * - * Functions for loading or configuring the mPIPE classifier program. - * - * The mPIPE classification processors all run a special "classifier" - * program which, for each incoming packet, parses the packet headers, - * encodes some packet metadata in the "idesc", and either drops the - * packet, or picks a notif ring to handle the packet, and a buffer - * stack to contain the packet, usually based on the channel, VLAN, - * dMAC, flow hash, and packet size, under the guidance of the "rules" - * API described below. - * - * @section gxio_mpipe_classifier_default Default Classifier - * - * The MDE provides a simple "default" classifier program. It is - * shipped as source in "$TILERA_ROOT/src/sys/mpipe/classifier.c", - * which serves as its official documentation. It is shipped as a - * binary program in "$TILERA_ROOT/tile/boot/classifier", which is - * automatically included in bootroms created by "tile-monitor", and - * is automatically loaded by the hypervisor at boot time. - * - * The L2 analysis handles LLC packets, SNAP packets, and "VLAN - * wrappers" (keeping the outer VLAN). - * - * The L3 analysis handles IPv4 and IPv6, dropping packets with bad - * IPv4 header checksums, requesting computation of a TCP/UDP checksum - * if appropriate, and hashing the dest and src IP addresses, plus the - * ports for TCP/UDP packets, into the flow hash. No special analysis - * is done for "fragmented" packets or "tunneling" protocols. Thus, - * the first fragment of a fragmented TCP/UDP packet is hashed using - * src/dest IP address and ports and all subsequent fragments are only - * hashed according to src/dest IP address. - * - * The L3 analysis handles other packets too, hashing the dMAC - * smac into a flow hash. - * - * The channel, VLAN, and dMAC used to pick a "rule" (see the - * "rules" APIs below), which in turn is used to pick a buffer stack - * (based on the packet size) and a bucket (based on the flow hash). - * - * To receive traffic matching a particular (channel/VLAN/dMAC - * pattern, an application should allocate its own buffer stacks and - * load balancer buckets, and map traffic to those stacks and buckets, - * as decribed by the "rules" API below. - * - * Various packet metadata is encoded in the idesc. The flow hash is - * four bytes at 0x0C. The VLAN is two bytes at 0x10. The ethtype is - * two bytes at 0x12. The l3 start is one byte at 0x14. The l4 start - * is one byte at 0x15 for IPv4 and IPv6 packets, and otherwise zero. - * The protocol is one byte at 0x16 for IPv4 and IPv6 packets, and - * otherwise zero. - * - * @section gxio_mpipe_classifier_custom Custom Classifiers. - * - * A custom classifier may be created using "tile-mpipe-cc" with a - * customized version of the default classifier sources. - * - * The custom classifier may be included in bootroms using the - * "--classifier" option to "tile-monitor", or loaded dynamically - * using gxio_mpipe_classifier_load_from_file(). - * - * Be aware that "extreme" customizations may break the assumptions of - * the "rules" APIs described below, but simple customizations, such - * as adding new packet metadata, should be fine. - */ - -/* A set of classifier rules, plus a context. */ -typedef struct { - - /* The context. */ - gxio_mpipe_context_t *context; - - /* The actual rules. */ - gxio_mpipe_rules_list_t list; - -} gxio_mpipe_rules_t; - -/* Initialize a classifier program rules list. - * - * This function can be called on a previously initialized rules list - * to discard any previously added rules. - * - * @param rules Rules list to initialize. - * @param context An initialized mPIPE context. - */ -extern void gxio_mpipe_rules_init(gxio_mpipe_rules_t *rules, - gxio_mpipe_context_t *context); - -/* Begin a new rule on the indicated rules list. - * - * Note that an empty rule matches all packets, but an empty rule list - * matches no packets. - * - * @param rules Rules list to which new rule is appended. - * @param bucket First load balancer bucket to which packets will be - * delivered. - * @param num_buckets Number of buckets (must be a power of two) across - * which packets will be distributed based on the "flow hash". - * @param stacks Either NULL, to assign each packet to the smallest - * initialized buffer stack which does not induce chaining (and to - * drop packets which exceed the largest initialized buffer stack - * buffer size), or an array, with each entry indicating which buffer - * stack should be used for packets up to that size (with 255 - * indicating that those packets should be dropped). - * @return 0 on success, or a negative error code on failure. - */ -extern int gxio_mpipe_rules_begin(gxio_mpipe_rules_t *rules, - unsigned int bucket, - unsigned int num_buckets, - gxio_mpipe_rules_stacks_t *stacks); - -/* Set the headroom of the current rule. - * - * @param rules Rules list whose current rule will be modified. - * @param headroom The headroom. - * @return 0 on success, or a negative error code on failure. - */ -extern int gxio_mpipe_rules_set_headroom(gxio_mpipe_rules_t *rules, - uint8_t headroom); - -/* Indicate that packets from a particular channel can be delivered - * to the buckets and buffer stacks associated with the current rule. - * - * Channels added must be associated with links opened by the mPIPE context - * used in gxio_mpipe_rules_init(). A rule with no channels is equivalent - * to a rule naming all such associated channels. - * - * @param rules Rules list whose current rule will be modified. - * @param channel The channel to add. - * @return 0 on success, or a negative error code on failure. - */ -extern int gxio_mpipe_rules_add_channel(gxio_mpipe_rules_t *rules, - unsigned int channel); - -/* Commit rules. - * - * The rules are sent to the hypervisor, where they are combined with - * the rules from other apps, and used to program the hardware classifier. - * - * Note that if this function returns an error, then the rules will NOT - * have been committed, even if the error is due to interactions with - * rules from another app. - * - * @param rules Rules list to commit. - * @return 0 on success, or a negative error code on failure. - */ -extern int gxio_mpipe_rules_commit(gxio_mpipe_rules_t *rules); - -/***************************************************************** - * Ingress Queue Wrapper * - ******************************************************************/ - -/* - * - * Convenience functions for receiving packets from a NotifRing and - * sending packets via an eDMA ring. - * - * The mpipe ingress and egress hardware uses shared memory packet - * descriptors to describe packets that have arrived on ingress or - * are destined for egress. These descriptors are stored in shared - * memory ring buffers and written or read by hardware as necessary. - * The gxio library provides wrapper functions that manage the head and - * tail pointers for these rings, allowing the user to easily read or - * write packet descriptors. - * - * The initialization interface for ingress and egress rings is quite - * similar. For example, to create an ingress queue, the user passes - * a ::gxio_mpipe_iqueue_t state object, a ring number from - * gxio_mpipe_alloc_notif_rings(), and the address of memory to hold a - * ring buffer to the gxio_mpipe_iqueue_init() function. The function - * returns success when the state object has been initialized and the - * hardware configured to deliver packets to the specified ring - * buffer. Similarly, gxio_mpipe_equeue_init() takes a - * ::gxio_mpipe_equeue_t state object, a ring number from - * gxio_mpipe_alloc_edma_rings(), and a shared memory buffer. - * - * @section gxio_mpipe_iqueue Working with Ingress Queues - * - * Once initialized, the gxio_mpipe_iqueue_t API provides two flows - * for getting the ::gxio_mpipe_idesc_t packet descriptor associated - * with incoming packets. The simplest is to call - * gxio_mpipe_iqueue_get() or gxio_mpipe_iqueue_try_get(). These - * functions copy the oldest packet descriptor out of the NotifRing and - * into a descriptor provided by the caller. They also immediately - * inform the hardware that a descriptor has been processed. - * - * For applications with stringent performance requirements, higher - * efficiency can be achieved by avoiding the packet descriptor copy - * and processing multiple descriptors at once. The - * gxio_mpipe_iqueue_peek() and gxio_mpipe_iqueue_try_peek() functions - * allow such optimizations. These functions provide a pointer to the - * next valid ingress descriptor in the NotifRing's shared memory ring - * buffer, and a count of how many contiguous descriptors are ready to - * be processed. The application can then process any number of those - * descriptors in place, calling gxio_mpipe_iqueue_consume() to inform - * the hardware after each one has been processed. - * - * @section gxio_mpipe_equeue Working with Egress Queues - * - * Similarly, the egress queue API provides a high-performance - * interface plus a simple wrapper for use in posting - * ::gxio_mpipe_edesc_t egress packet descriptors. The simple - * version, gxio_mpipe_equeue_put(), allows the programmer to wait for - * an eDMA ring slot to become available and write a single descriptor - * into the ring. - * - * Alternatively, you can reserve slots in the eDMA ring using - * gxio_mpipe_equeue_reserve() or gxio_mpipe_equeue_try_reserve(), and - * then fill in each slot using gxio_mpipe_equeue_put_at(). This - * capability can be used to amortize the cost of reserving slots - * across several packets. It also allows gather operations to be - * performed on a shared equeue, by ensuring that the edescs for all - * the fragments are all contiguous in the eDMA ring. - * - * The gxio_mpipe_equeue_reserve() and gxio_mpipe_equeue_try_reserve() - * functions return a 63-bit "completion slot", which is actually a - * sequence number, the low bits of which indicate the ring buffer - * index and the high bits the number of times the application has - * gone around the egress ring buffer. The extra bits allow an - * application to check for egress completion by calling - * gxio_mpipe_equeue_is_complete() to see whether a particular 'slot' - * number has finished. Given the maximum packet rates of the Gx - * processor, the 63-bit slot number will never wrap. - * - * In practice, most applications use the ::gxio_mpipe_edesc_t::hwb - * bit to indicate that the buffers containing egress packet data - * should be pushed onto a buffer stack when egress is complete. Such - * applications generally do not need to know when an egress operation - * completes (since there is no need to free a buffer post-egress), - * and thus can use the optimized gxio_mpipe_equeue_reserve_fast() or - * gxio_mpipe_equeue_try_reserve_fast() functions, which return a 24 - * bit "slot", instead of a 63-bit "completion slot". - * - * Once a slot has been "reserved", it MUST be filled. If the - * application reserves a slot and then decides that it does not - * actually need it, it can set the ::gxio_mpipe_edesc_t::ns (no send) - * bit on the descriptor passed to gxio_mpipe_equeue_put_at() to - * indicate that no data should be sent. This technique can also be - * used to drop an incoming packet, instead of forwarding it, since - * any buffer will still be pushed onto the buffer stack when the - * egress descriptor is processed. - */ - -/* A convenient interface to a NotifRing, for use by a single thread. - */ -typedef struct { - - /* The context. */ - gxio_mpipe_context_t *context; - - /* The actual NotifRing. */ - gxio_mpipe_idesc_t *idescs; - - /* The number of entries. */ - unsigned long num_entries; - - /* The number of entries minus one. */ - unsigned long mask_num_entries; - - /* The log2() of the number of entries. */ - unsigned long log2_num_entries; - - /* The next entry. */ - unsigned int head; - - /* The NotifRing id. */ - unsigned int ring; - -#ifdef __BIG_ENDIAN__ - /* The number of byteswapped entries. */ - unsigned int swapped; -#endif - -} gxio_mpipe_iqueue_t; - -/* Initialize an "iqueue". - * - * Takes the iqueue plus the same args as gxio_mpipe_init_notif_ring(). - */ -extern int gxio_mpipe_iqueue_init(gxio_mpipe_iqueue_t *iqueue, - gxio_mpipe_context_t *context, - unsigned int ring, - void *mem, size_t mem_size, - unsigned int mem_flags); - -/* Advance over some old entries in an iqueue. - * - * Please see the documentation for gxio_mpipe_iqueue_consume(). - * - * @param iqueue An ingress queue initialized via gxio_mpipe_iqueue_init(). - * @param count The number of entries to advance over. - */ -static inline void gxio_mpipe_iqueue_advance(gxio_mpipe_iqueue_t *iqueue, - int count) -{ - /* Advance with proper wrap. */ - int head = iqueue->head + count; - iqueue->head = - (head & iqueue->mask_num_entries) + - (head >> iqueue->log2_num_entries); - -#ifdef __BIG_ENDIAN__ - /* HACK: Track swapped entries. */ - iqueue->swapped -= count; -#endif -} - -/* Release the ring and bucket for an old entry in an iqueue. - * - * Releasing the ring allows more packets to be delivered to the ring. - * - * Releasing the bucket allows flows using the bucket to be moved to a - * new ring when using GXIO_MPIPE_BUCKET_DYNAMIC_FLOW_AFFINITY. - * - * This function is shorthand for "gxio_mpipe_credit(iqueue->context, - * iqueue->ring, idesc->bucket_id, 1)", and it may be more convenient - * to make that underlying call, using those values, instead of - * tracking the entire "idesc". - * - * If packet processing is deferred, optimal performance requires that - * the releasing be deferred as well. - * - * Please see the documentation for gxio_mpipe_iqueue_consume(). - * - * @param iqueue An ingress queue initialized via gxio_mpipe_iqueue_init(). - * @param idesc The descriptor which was processed. - */ -static inline void gxio_mpipe_iqueue_release(gxio_mpipe_iqueue_t *iqueue, - gxio_mpipe_idesc_t *idesc) -{ - gxio_mpipe_credit(iqueue->context, iqueue->ring, idesc->bucket_id, 1); -} - -/* Consume a packet from an "iqueue". - * - * After processing packets peeked at via gxio_mpipe_iqueue_peek() - * or gxio_mpipe_iqueue_try_peek(), you must call this function, or - * gxio_mpipe_iqueue_advance() plus gxio_mpipe_iqueue_release(), to - * advance over those entries, and release their rings and buckets. - * - * You may call this function as each packet is processed, or you can - * wait until several packets have been processed. - * - * Note that if you are using a single bucket, and you are handling - * batches of N packets, then you can replace several calls to this - * function with calls to "gxio_mpipe_iqueue_advance(iqueue, N)" and - * "gxio_mpipe_credit(iqueue->context, iqueue->ring, bucket, N)". - * - * Note that if your classifier sets "idesc->nr", then you should - * explicitly call "gxio_mpipe_iqueue_advance(iqueue, idesc)" plus - * "gxio_mpipe_credit(iqueue->context, iqueue->ring, -1, 1)", to - * avoid incorrectly crediting the (unused) bucket. - * - * @param iqueue An ingress queue initialized via gxio_mpipe_iqueue_init(). - * @param idesc The descriptor which was processed. - */ -static inline void gxio_mpipe_iqueue_consume(gxio_mpipe_iqueue_t *iqueue, - gxio_mpipe_idesc_t *idesc) -{ - gxio_mpipe_iqueue_advance(iqueue, 1); - gxio_mpipe_iqueue_release(iqueue, idesc); -} - -/* Peek at the next packet(s) in an "iqueue", without waiting. - * - * If no packets are available, fills idesc_ref with NULL, and then - * returns ::GXIO_MPIPE_ERR_IQUEUE_EMPTY. Otherwise, fills idesc_ref - * with the address of the next valid packet descriptor, and returns - * the maximum number of valid descriptors which can be processed. - * You may process fewer descriptors if desired. - * - * Call gxio_mpipe_iqueue_consume() on each packet once it has been - * processed (or dropped), to allow more packets to be delivered. - * - * @param iqueue An ingress queue initialized via gxio_mpipe_iqueue_init(). - * @param idesc_ref A pointer to a packet descriptor pointer. - * @return The (positive) number of packets which can be processed, - * or ::GXIO_MPIPE_ERR_IQUEUE_EMPTY if no packets are available. - */ -static inline int gxio_mpipe_iqueue_try_peek(gxio_mpipe_iqueue_t *iqueue, - gxio_mpipe_idesc_t **idesc_ref) -{ - gxio_mpipe_idesc_t *next; - - uint64_t head = iqueue->head; - uint64_t tail = __gxio_mmio_read(iqueue->idescs); - - /* Available entries. */ - uint64_t avail = - (tail >= head) ? (tail - head) : (iqueue->num_entries - head); - - if (avail == 0) { - *idesc_ref = NULL; - return GXIO_MPIPE_ERR_IQUEUE_EMPTY; - } - - next = &iqueue->idescs[head]; - - /* ISSUE: Is this helpful? */ - __insn_prefetch(next); - -#ifdef __BIG_ENDIAN__ - /* HACK: Swap new entries directly in memory. */ - { - int i, j; - for (i = iqueue->swapped; i < avail; i++) { - for (j = 0; j < 8; j++) - next[i].words[j] = - __builtin_bswap64(next[i].words[j]); - } - iqueue->swapped = avail; - } -#endif - - *idesc_ref = next; - - return avail; -} - -/* Drop a packet by pushing its buffer (if appropriate). - * - * NOTE: The caller must still call gxio_mpipe_iqueue_consume() if idesc - * came from gxio_mpipe_iqueue_try_peek() or gxio_mpipe_iqueue_peek(). - * - * @param iqueue An ingress queue initialized via gxio_mpipe_iqueue_init(). - * @param idesc A packet descriptor. - */ -static inline void gxio_mpipe_iqueue_drop(gxio_mpipe_iqueue_t *iqueue, - gxio_mpipe_idesc_t *idesc) -{ - /* FIXME: Handle "chaining" properly. */ - - if (!idesc->be) { - unsigned char *va = gxio_mpipe_idesc_get_va(idesc); - gxio_mpipe_push_buffer(iqueue->context, idesc->stack_idx, va); - } -} - -/***************************************************************** - * Egress Queue Wrapper * - ******************************************************************/ - -/* A convenient, thread-safe interface to an eDMA ring. */ -typedef struct { - - /* State object for tracking head and tail pointers. */ - __gxio_dma_queue_t dma_queue; - - /* The ring entries. */ - gxio_mpipe_edesc_t *edescs; - - /* The number of entries minus one. */ - unsigned long mask_num_entries; - - /* The log2() of the number of entries. */ - unsigned long log2_num_entries; - - /* The context. */ - gxio_mpipe_context_t *context; - - /* The ering. */ - unsigned int ering; - - /* The channel. */ - unsigned int channel; - -} gxio_mpipe_equeue_t; - -/* Initialize an "equeue". - * - * This function uses gxio_mpipe_init_edma_ring() to initialize the - * underlying edma_ring using the provided arguments. - * - * @param equeue An egress queue to be initialized. - * @param context An initialized mPIPE context. - * @param ering The eDMA ring index. - * @param channel The channel to use. This must be one of the channels - * associated with the context's set of open links. - * @param mem A physically contiguous region of memory to be filled - * with a ring of ::gxio_mpipe_edesc_t structures. - * @param mem_size Number of bytes in the ring. Must be 512, 2048, - * 8192 or 65536, times 16 (i.e. sizeof(gxio_mpipe_edesc_t)). - * @param mem_flags ::gxio_mpipe_mem_flags_e memory flags. - * - * @return 0 on success, ::GXIO_MPIPE_ERR_BAD_EDMA_RING or - * ::GXIO_ERR_INVAL_MEMORY_SIZE on failure. - */ -extern int gxio_mpipe_equeue_init(gxio_mpipe_equeue_t *equeue, - gxio_mpipe_context_t *context, - unsigned int ering, - unsigned int channel, - void *mem, unsigned int mem_size, - unsigned int mem_flags); - -/* Reserve completion slots for edescs. - * - * Use gxio_mpipe_equeue_put_at() to actually populate the slots. - * - * This function is slower than gxio_mpipe_equeue_reserve_fast(), but - * returns a full 64 bit completion slot, which can be used with - * gxio_mpipe_equeue_is_complete(). - * - * @param equeue An egress queue initialized via gxio_mpipe_equeue_init(). - * @param num Number of slots to reserve (must be non-zero). - * @return The first reserved completion slot, or a negative error code. - */ -static inline int64_t gxio_mpipe_equeue_reserve(gxio_mpipe_equeue_t *equeue, - unsigned int num) -{ - return __gxio_dma_queue_reserve_aux(&equeue->dma_queue, num, true); -} - -/* Reserve completion slots for edescs, if possible. - * - * Use gxio_mpipe_equeue_put_at() to actually populate the slots. - * - * This function is slower than gxio_mpipe_equeue_try_reserve_fast(), - * but returns a full 64 bit completion slot, which can be used with - * gxio_mpipe_equeue_is_complete(). - * - * @param equeue An egress queue initialized via gxio_mpipe_equeue_init(). - * @param num Number of slots to reserve (must be non-zero). - * @return The first reserved completion slot, or a negative error code. - */ -static inline int64_t gxio_mpipe_equeue_try_reserve(gxio_mpipe_equeue_t - *equeue, unsigned int num) -{ - return __gxio_dma_queue_reserve_aux(&equeue->dma_queue, num, false); -} - -/* Reserve slots for edescs. - * - * Use gxio_mpipe_equeue_put_at() to actually populate the slots. - * - * This function is faster than gxio_mpipe_equeue_reserve(), but - * returns a 24 bit slot (instead of a 64 bit completion slot), which - * thus cannot be used with gxio_mpipe_equeue_is_complete(). - * - * @param equeue An egress queue initialized via gxio_mpipe_equeue_init(). - * @param num Number of slots to reserve (should be non-zero). - * @return The first reserved slot, or a negative error code. - */ -static inline int64_t gxio_mpipe_equeue_reserve_fast(gxio_mpipe_equeue_t - *equeue, unsigned int num) -{ - return __gxio_dma_queue_reserve(&equeue->dma_queue, num, true, false); -} - -/* Reserve slots for edescs, if possible. - * - * Use gxio_mpipe_equeue_put_at() to actually populate the slots. - * - * This function is faster than gxio_mpipe_equeue_try_reserve(), but - * returns a 24 bit slot (instead of a 64 bit completion slot), which - * thus cannot be used with gxio_mpipe_equeue_is_complete(). - * - * @param equeue An egress queue initialized via gxio_mpipe_equeue_init(). - * @param num Number of slots to reserve (should be non-zero). - * @return The first reserved slot, or a negative error code. - */ -static inline int64_t gxio_mpipe_equeue_try_reserve_fast(gxio_mpipe_equeue_t - *equeue, - unsigned int num) -{ - return __gxio_dma_queue_reserve(&equeue->dma_queue, num, false, false); -} - -/* - * HACK: This helper function tricks gcc 4.6 into avoiding saving - * a copy of "edesc->words[0]" on the stack for no obvious reason. - */ - -static inline void gxio_mpipe_equeue_put_at_aux(gxio_mpipe_equeue_t *equeue, - uint_reg_t ew[2], - unsigned long slot) -{ - unsigned long edma_slot = slot & equeue->mask_num_entries; - gxio_mpipe_edesc_t *edesc_p = &equeue->edescs[edma_slot]; - - /* - * ISSUE: Could set eDMA ring to be on generation 1 at start, which - * would avoid the negation here, perhaps allowing "__insn_bfins()". - */ - ew[0] |= !((slot >> equeue->log2_num_entries) & 1); - - /* - * NOTE: We use "__gxio_mpipe_write()", plus the fact that the eDMA - * queue alignment restrictions ensure that these two words are on - * the same cacheline, to force proper ordering between the stores. - */ - __gxio_mmio_write64(&edesc_p->words[1], ew[1]); - __gxio_mmio_write64(&edesc_p->words[0], ew[0]); -} - -/* Post an edesc to a given slot in an equeue. - * - * This function copies the supplied edesc into entry "slot mod N" in - * the underlying ring, setting the "gen" bit to the appropriate value - * based on "(slot mod N*2)", where "N" is the size of the ring. Note - * that the higher bits of slot are unused, and thus, this function - * can handle "slots" as well as "completion slots". - * - * Normally this function is used to fill in slots reserved by - * gxio_mpipe_equeue_try_reserve(), gxio_mpipe_equeue_reserve(), - * gxio_mpipe_equeue_try_reserve_fast(), or - * gxio_mpipe_equeue_reserve_fast(), - * - * This function can also be used without "reserving" slots, if the - * application KNOWS that the ring can never overflow, for example, by - * pushing fewer buffers into the buffer stacks than there are total - * slots in the equeue, but this is NOT recommended. - * - * @param equeue An egress queue initialized via gxio_mpipe_equeue_init(). - * @param edesc The egress descriptor to be posted. - * @param slot An egress slot (only the low bits are actually used). - */ -static inline void gxio_mpipe_equeue_put_at(gxio_mpipe_equeue_t *equeue, - gxio_mpipe_edesc_t edesc, - unsigned long slot) -{ - gxio_mpipe_equeue_put_at_aux(equeue, edesc.words, slot); -} - -/* Post an edesc to the next slot in an equeue. - * - * This is a convenience wrapper around - * gxio_mpipe_equeue_reserve_fast() and gxio_mpipe_equeue_put_at(). - * - * @param equeue An egress queue initialized via gxio_mpipe_equeue_init(). - * @param edesc The egress descriptor to be posted. - * @return 0 on success. - */ -static inline int gxio_mpipe_equeue_put(gxio_mpipe_equeue_t *equeue, - gxio_mpipe_edesc_t edesc) -{ - int64_t slot = gxio_mpipe_equeue_reserve_fast(equeue, 1); - if (slot < 0) - return (int)slot; - - gxio_mpipe_equeue_put_at(equeue, edesc, slot); - - return 0; -} - -/* Ask the mPIPE hardware to egress outstanding packets immediately. - * - * This call is not necessary, but may slightly reduce overall latency. - * - * Technically, you should flush all gxio_mpipe_equeue_put_at() writes - * to memory before calling this function, to ensure the descriptors - * are visible in memory before the mPIPE hardware actually looks for - * them. But this should be very rare, and the only side effect would - * be increased latency, so it is up to the caller to decide whether - * or not to flush memory. - * - * @param equeue An egress queue initialized via gxio_mpipe_equeue_init(). - */ -static inline void gxio_mpipe_equeue_flush(gxio_mpipe_equeue_t *equeue) -{ - /* Use "ring_idx = 0" and "count = 0" to "wake up" the eDMA ring. */ - MPIPE_EDMA_POST_REGION_VAL_t val = { {0} }; - /* Flush the write buffers. */ - __insn_flushwb(); - __gxio_mmio_write(equeue->dma_queue.post_region_addr, val.word); -} - -/* Determine if a given edesc has been completed. - * - * Note that this function requires a "completion slot", and thus may - * NOT be used with a "slot" from gxio_mpipe_equeue_reserve_fast() or - * gxio_mpipe_equeue_try_reserve_fast(). - * - * @param equeue An egress queue initialized via gxio_mpipe_equeue_init(). - * @param completion_slot The completion slot used by the edesc. - * @param update If true, and the desc does not appear to have completed - * yet, then update any software cache of the hardware completion counter, - * and check again. This should normally be true. - * @return True iff the given edesc has been completed. - */ -static inline int gxio_mpipe_equeue_is_complete(gxio_mpipe_equeue_t *equeue, - int64_t completion_slot, - int update) -{ - return __gxio_dma_queue_is_complete(&equeue->dma_queue, - completion_slot, update); -} - -/* Set the snf (store and forward) size for an equeue. - * - * The snf size for an equeue defaults to 1536, and encodes the size - * of the largest packet for which egress is guaranteed to avoid - * transmission underruns and/or corrupt checksums under heavy load. - * - * The snf size affects a global resource pool which cannot support, - * for example, all 24 equeues each requesting an snf size of 8K. - * - * To ensure that jumbo packets can be egressed properly, the snf size - * should be set to the size of the largest possible packet, which - * will usually be limited by the size of the app's largest buffer. - * - * This is a convenience wrapper around - * gxio_mpipe_config_edma_ring_blks(). - * - * This function should not be called after any egress has been done - * on the equeue. - * - * @param equeue An egress queue initialized via gxio_mpipe_equeue_init(). - * @param size The snf size, in bytes. - * @return Zero on success, negative error otherwise. - */ -static inline int gxio_mpipe_equeue_set_snf_size(gxio_mpipe_equeue_t *equeue, - size_t size) -{ - int blks = (size + 127) / 128; - return gxio_mpipe_config_edma_ring_blks(equeue->context, equeue->ering, - blks + 1, blks, 1); -} - -/***************************************************************** - * Link Management * - ******************************************************************/ - -/* - * - * Functions for manipulating and sensing the state and configuration - * of physical network links. - * - * @section gxio_mpipe_link_perm Link Permissions - * - * Opening a link (with gxio_mpipe_link_open()) requests a set of link - * permissions, which control what may be done with the link, and potentially - * what permissions may be granted to other processes. - * - * Data permission allows the process to receive packets from the link by - * specifying the link's channel number in mPIPE packet distribution rules, - * and to send packets to the link by using the link's channel number as - * the target for an eDMA ring. - * - * Stats permission allows the process to retrieve link attributes (such as - * the speeds it is capable of running at, or whether it is currently up), and - * to read and write certain statistics-related registers in the link's MAC. - * - * Control permission allows the process to retrieve and modify link attributes - * (so that it may, for example, bring the link up and take it down), and - * read and write many registers in the link's MAC and PHY. - * - * Any permission may be requested as shared, which allows other processes - * to also request shared permission, or exclusive, which prevents other - * processes from requesting it. In keeping with GXIO's typical usage in - * an embedded environment, the defaults for all permissions are shared. - * - * Permissions are granted on a first-come, first-served basis, so if two - * applications request an exclusive permission on the same link, the one - * to run first will win. Note, however, that some system components, like - * the kernel Ethernet driver, may get an opportunity to open links before - * any applications run. - * - * @section gxio_mpipe_link_names Link Names - * - * Link names are of the form gbe<em>number</em> (for Gigabit Ethernet), - * xgbe<em>number</em> (for 10 Gigabit Ethernet), loop<em>number</em> (for - * internal mPIPE loopback), or ilk<em>number</em>/<em>channel</em> - * (for Interlaken links); for instance, gbe0, xgbe1, loop3, and - * ilk0/12 are all possible link names. The correspondence between - * the link name and an mPIPE instance number or mPIPE channel number is - * system-dependent; all links will not exist on all systems, and the set - * of numbers used for a particular link type may not start at zero and may - * not be contiguous. Use gxio_mpipe_link_enumerate() to retrieve the set of - * links which exist on a system, and always use gxio_mpipe_link_instance() - * to determine which mPIPE controls a particular link. - * - * Note that in some cases, links may share hardware, such as PHYs, or - * internal mPIPE buffers; in these cases, only one of the links may be - * opened at a time. This is especially common with xgbe and gbe ports, - * since each xgbe port uses 4 SERDES lanes, each of which may also be - * configured as one gbe port. - * - * @section gxio_mpipe_link_states Link States - * - * The mPIPE link management model revolves around three different states, - * which are maintained for each link: - * - * 1. The <em>current</em> link state: is the link up now, and if so, at - * what speed? - * - * 2. The <em>desired</em> link state: what do we want the link state to be? - * The system is always working to make this state the current state; - * thus, if the desired state is up, and the link is down, we'll be - * constantly trying to bring it up, automatically. - * - * 3. The <em>possible</em> link state: what speeds are valid for this - * particular link? Or, in other words, what are the capabilities of - * the link hardware? - * - * These link states are not, strictly speaking, related to application - * state; they may be manipulated at any time, whether or not the link - * is currently being used for data transfer. However, for convenience, - * gxio_mpipe_link_open() and gxio_mpipe_link_close() (or application exit) - * can affect the link state. These implicit link management operations - * may be modified or disabled by the use of link open flags. - * - * From an application, you can use gxio_mpipe_link_get_attr() - * and gxio_mpipe_link_set_attr() to manipulate the link states. - * gxio_mpipe_link_get_attr() with ::GXIO_MPIPE_LINK_POSSIBLE_STATE - * gets you the possible link state. gxio_mpipe_link_get_attr() with - * ::GXIO_MPIPE_LINK_CURRENT_STATE gets you the current link state. - * Finally, gxio_mpipe_link_set_attr() and gxio_mpipe_link_get_attr() - * with ::GXIO_MPIPE_LINK_DESIRED_STATE allow you to modify or retrieve - * the desired link state. - * - * If you want to manage a link from a part of your application which isn't - * involved in packet processing, you can use the ::GXIO_MPIPE_LINK_NO_DATA - * flags on a gxio_mpipe_link_open() call. This opens the link, but does - * not request data permission, so it does not conflict with any exclusive - * permissions which may be held by other processes. You can then can use - * gxio_mpipe_link_get_attr() and gxio_mpipe_link_set_attr() on this link - * object to bring up or take down the link. - * - * Some links support link state bits which support various loopback - * modes. ::GXIO_MPIPE_LINK_LOOP_MAC tests datapaths within the Tile - * Processor itself; ::GXIO_MPIPE_LINK_LOOP_PHY tests the datapath between - * the Tile Processor and the external physical layer interface chip; and - * ::GXIO_MPIPE_LINK_LOOP_EXT tests the entire network datapath with the - * aid of an external loopback connector. In addition to enabling hardware - * testing, such configuration can be useful for software testing, as well. - * - * When LOOP_MAC or LOOP_PHY is enabled, packets transmitted on a channel - * will be received by that channel, instead of being emitted on the - * physical link, and packets received on the physical link will be ignored. - * Other than that, all standard GXIO operations work as you might expect. - * Note that loopback operation requires that the link be brought up using - * one or more of the GXIO_MPIPE_LINK_SPEED_xxx link state bits. - * - * Those familiar with previous versions of the MDE on TILEPro hardware - * will notice significant similarities between the NetIO link management - * model and the mPIPE link management model. However, the NetIO model - * was developed in stages, and some of its features -- for instance, - * the default setting of certain flags -- were shaped by the need to be - * compatible with previous versions of NetIO. Since the features provided - * by the mPIPE hardware and the mPIPE GXIO library are significantly - * different than those provided by NetIO, in some cases, we have made - * different choices in the mPIPE link management API. Thus, please read - * this documentation carefully before assuming that mPIPE link management - * operations are exactly equivalent to their NetIO counterparts. - */ - -/* An object used to manage mPIPE link state and resources. */ -typedef struct { - /* The overall mPIPE context. */ - gxio_mpipe_context_t *context; - - /* The channel number used by this link. */ - uint8_t channel; - - /* The MAC index used by this link. */ - uint8_t mac; -} gxio_mpipe_link_t; - -/* Translate a link name to the instance number of the mPIPE shim which is - * connected to that link. This call does not verify whether the link is - * currently available, and does not reserve any link resources; - * gxio_mpipe_link_open() must be called to perform those functions. - * - * Typically applications will call this function to translate a link name - * to an mPIPE instance number; call gxio_mpipe_init(), passing it that - * instance number, to initialize the mPIPE shim; and then call - * gxio_mpipe_link_open(), passing it the same link name plus the mPIPE - * context, to configure the link. - * - * @param link_name Name of the link; see @ref gxio_mpipe_link_names. - * @return The mPIPE instance number which is associated with the named - * link, or a negative error code (::GXIO_ERR_NO_DEVICE) if the link does - * not exist. - */ -extern int gxio_mpipe_link_instance(const char *link_name); - -/* Retrieve one of this system's legal link names, and its MAC address. - * - * @param index Link name index. If a system supports N legal link names, - * then indices between 0 and N - 1, inclusive, each correspond to one of - * those names. Thus, to retrieve all of a system's legal link names, - * call this function in a loop, starting with an index of zero, and - * incrementing it once per iteration until -1 is returned. - * @param link_name Pointer to the buffer which will receive the retrieved - * link name. The buffer should contain space for at least - * ::GXIO_MPIPE_LINK_NAME_LEN bytes; the returned name, including the - * terminating null byte, will be no longer than that. - * @param link_name Pointer to the buffer which will receive the retrieved - * MAC address. The buffer should contain space for at least 6 bytes. - * @return Zero if a link name was successfully retrieved; -1 if one was - * not. - */ -extern int gxio_mpipe_link_enumerate_mac(int index, char *link_name, - uint8_t *mac_addr); - -/* Open an mPIPE link. - * - * A link must be opened before it may be used to send or receive packets, - * and before its state may be examined or changed. Depending up on the - * link's intended use, one or more link permissions may be requested via - * the flags parameter; see @ref gxio_mpipe_link_perm. In addition, flags - * may request that the link's state be modified at open time. See @ref - * gxio_mpipe_link_states and @ref gxio_mpipe_link_open_flags for more detail. - * - * @param link A link state object, which will be initialized if this - * function completes successfully. - * @param context An initialized mPIPE context. - * @param link_name Name of the link. - * @param flags Zero or more @ref gxio_mpipe_link_open_flags, ORed together. - * @return 0 if the link was successfully opened, or a negative error code. - * - */ -extern int gxio_mpipe_link_open(gxio_mpipe_link_t *link, - gxio_mpipe_context_t *context, - const char *link_name, unsigned int flags); - -/* Close an mPIPE link. - * - * Closing a link makes it available for use by other processes. Once - * a link has been closed, packets may no longer be sent on or received - * from the link, and its state may not be examined or changed. - * - * @param link A link state object, which will no longer be initialized - * if this function completes successfully. - * @return 0 if the link was successfully closed, or a negative error code. - * - */ -extern int gxio_mpipe_link_close(gxio_mpipe_link_t *link); - -/* Return a link's channel number. - * - * @param link A properly initialized link state object. - * @return The channel number for the link. - */ -static inline int gxio_mpipe_link_channel(gxio_mpipe_link_t *link) -{ - return link->channel; -} - -/* Set a link attribute. - * - * @param link A properly initialized link state object. - * @param attr An attribute from the set of @ref gxio_mpipe_link_attrs. - * @param val New value of the attribute. - * @return 0 if the attribute was successfully set, or a negative error - * code. - */ -extern int gxio_mpipe_link_set_attr(gxio_mpipe_link_t *link, uint32_t attr, - int64_t val); - -/////////////////////////////////////////////////////////////////// -// Timestamp // -/////////////////////////////////////////////////////////////////// - -/* Get the timestamp of mPIPE when this routine is called. - * - * @param context An initialized mPIPE context. - * @param ts A timespec structure to store the current clock. - * @return If the call was successful, zero; otherwise, a negative error - * code. - */ -extern int gxio_mpipe_get_timestamp(gxio_mpipe_context_t *context, - struct timespec64 *ts); - -/* Set the timestamp of mPIPE. - * - * @param context An initialized mPIPE context. - * @param ts A timespec structure to store the requested clock. - * @return If the call was successful, zero; otherwise, a negative error - * code. - */ -extern int gxio_mpipe_set_timestamp(gxio_mpipe_context_t *context, - const struct timespec64 *ts); - -/* Adjust the timestamp of mPIPE. - * - * @param context An initialized mPIPE context. - * @param delta A signed time offset to adjust, in nanoseconds. - * The absolute value of this parameter must be less than or - * equal to 1000000000. - * @return If the call was successful, zero; otherwise, a negative error - * code. - */ -extern int gxio_mpipe_adjust_timestamp(gxio_mpipe_context_t *context, - int64_t delta); - -/** Adjust the mPIPE timestamp clock frequency. - * - * @param context An initialized mPIPE context. - * @param ppb A 32-bit signed PPB (Parts Per Billion) value to adjust. - * The absolute value of ppb must be less than or equal to 1000000000. - * Values less than about 30000 will generally cause a GXIO_ERR_INVAL - * return due to the granularity of the hardware that converts reference - * clock cycles into seconds and nanoseconds. - * @return If the call was successful, zero; otherwise, a negative error - * code. - */ -extern int gxio_mpipe_adjust_timestamp_freq(gxio_mpipe_context_t* context, - int32_t ppb); - -#endif /* !_GXIO_MPIPE_H_ */ |