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Diffstat (limited to 'drivers/net/ethernet/cavium/liquidio/octeon_console.c')
-rw-r--r--drivers/net/ethernet/cavium/liquidio/octeon_console.c723
1 files changed, 723 insertions, 0 deletions
diff --git a/drivers/net/ethernet/cavium/liquidio/octeon_console.c b/drivers/net/ethernet/cavium/liquidio/octeon_console.c
new file mode 100644
index 000000000000..466147e409c9
--- /dev/null
+++ b/drivers/net/ethernet/cavium/liquidio/octeon_console.c
@@ -0,0 +1,723 @@
+/**********************************************************************
+* Author: Cavium, Inc.
+*
+* Contact: support@cavium.com
+* Please include "LiquidIO" in the subject.
+*
+* Copyright (c) 2003-2015 Cavium, Inc.
+*
+* This file is free software; you can redistribute it and/or modify
+* it under the terms of the GNU General Public License, Version 2, as
+* published by the Free Software Foundation.
+*
+* This file is distributed in the hope that it will be useful, but
+* AS-IS and WITHOUT ANY WARRANTY; without even the implied warranty
+* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, TITLE, or
+* NONINFRINGEMENT. See the GNU General Public License for more
+* details.
+*
+* This file may also be available under a different license from Cavium.
+* Contact Cavium, Inc. for more information
+**********************************************************************/
+
+/**
+ * @file octeon_console.c
+ */
+#include <linux/version.h>
+#include <linux/types.h>
+#include <linux/list.h>
+#include <linux/interrupt.h>
+#include <linux/pci.h>
+#include <linux/kthread.h>
+#include <linux/netdevice.h>
+#include "octeon_config.h"
+#include "liquidio_common.h"
+#include "octeon_droq.h"
+#include "octeon_iq.h"
+#include "response_manager.h"
+#include "octeon_device.h"
+#include "octeon_nic.h"
+#include "octeon_main.h"
+#include "octeon_network.h"
+#include "cn66xx_regs.h"
+#include "cn66xx_device.h"
+#include "cn68xx_regs.h"
+#include "cn68xx_device.h"
+#include "liquidio_image.h"
+#include "octeon_mem_ops.h"
+
+static void octeon_remote_lock(void);
+static void octeon_remote_unlock(void);
+static u64 cvmx_bootmem_phy_named_block_find(struct octeon_device *oct,
+ const char *name,
+ u32 flags);
+
+#define MIN(a, b) min((a), (b))
+#define CAST_ULL(v) ((u64)(v))
+
+#define BOOTLOADER_PCI_READ_BUFFER_DATA_ADDR 0x0006c008
+#define BOOTLOADER_PCI_READ_BUFFER_LEN_ADDR 0x0006c004
+#define BOOTLOADER_PCI_READ_BUFFER_OWNER_ADDR 0x0006c000
+#define BOOTLOADER_PCI_READ_DESC_ADDR 0x0006c100
+#define BOOTLOADER_PCI_WRITE_BUFFER_STR_LEN 248
+
+#define OCTEON_PCI_IO_BUF_OWNER_OCTEON 0x00000001
+#define OCTEON_PCI_IO_BUF_OWNER_HOST 0x00000002
+
+/** Can change without breaking ABI */
+#define CVMX_BOOTMEM_NUM_NAMED_BLOCKS 64
+
+/** minimum alignment of bootmem alloced blocks */
+#define CVMX_BOOTMEM_ALIGNMENT_SIZE (16ull)
+
+/** CVMX bootmem descriptor major version */
+#define CVMX_BOOTMEM_DESC_MAJ_VER 3
+/* CVMX bootmem descriptor minor version */
+#define CVMX_BOOTMEM_DESC_MIN_VER 0
+
+/* Current versions */
+#define OCTEON_PCI_CONSOLE_MAJOR_VERSION 1
+#define OCTEON_PCI_CONSOLE_MINOR_VERSION 0
+#define OCTEON_PCI_CONSOLE_BLOCK_NAME "__pci_console"
+#define OCTEON_CONSOLE_POLL_INTERVAL_MS 100 /* 10 times per second */
+
+/* First three members of cvmx_bootmem_desc are left in original
+** positions for backwards compatibility.
+** Assumes big endian target
+*/
+struct cvmx_bootmem_desc {
+ /** spinlock to control access to list */
+ u32 lock;
+
+ /** flags for indicating various conditions */
+ u32 flags;
+
+ u64 head_addr;
+
+ /** incremented changed when incompatible changes made */
+ u32 major_version;
+
+ /** incremented changed when compatible changes made,
+ * reset to zero when major incremented
+ */
+ u32 minor_version;
+
+ u64 app_data_addr;
+ u64 app_data_size;
+
+ /** number of elements in named blocks array */
+ u32 nb_num_blocks;
+
+ /** length of name array in bootmem blocks */
+ u32 named_block_name_len;
+
+ /** address of named memory block descriptors */
+ u64 named_block_array_addr;
+};
+
+/* Structure that defines a single console.
+ *
+ * Note: when read_index == write_index, the buffer is empty.
+ * The actual usable size of each console is console_buf_size -1;
+ */
+struct octeon_pci_console {
+ u64 input_base_addr;
+ u32 input_read_index;
+ u32 input_write_index;
+ u64 output_base_addr;
+ u32 output_read_index;
+ u32 output_write_index;
+ u32 lock;
+ u32 buf_size;
+};
+
+/* This is the main container structure that contains all the information
+ * about all PCI consoles. The address of this structure is passed to various
+ * routines that operation on PCI consoles.
+ */
+struct octeon_pci_console_desc {
+ u32 major_version;
+ u32 minor_version;
+ u32 lock;
+ u32 flags;
+ u32 num_consoles;
+ u32 pad;
+ /* must be 64 bit aligned here... */
+ /* Array of addresses of octeon_pci_console structures */
+ u64 console_addr_array[0];
+ /* Implicit storage for console_addr_array */
+};
+
+/**
+ * This macro returns the size of a member of a structure.
+ * Logically it is the same as "sizeof(s::field)" in C++, but
+ * C lacks the "::" operator.
+ */
+#define SIZEOF_FIELD(s, field) sizeof(((s *)NULL)->field)
+
+/**
+ * This macro returns a member of the cvmx_bootmem_desc
+ * structure. These members can't be directly addressed as
+ * they might be in memory not directly reachable. In the case
+ * where bootmem is compiled with LINUX_HOST, the structure
+ * itself might be located on a remote Octeon. The argument
+ * "field" is the member name of the cvmx_bootmem_desc to read.
+ * Regardless of the type of the field, the return type is always
+ * a u64.
+ */
+#define CVMX_BOOTMEM_DESC_GET_FIELD(oct, field) \
+ __cvmx_bootmem_desc_get(oct, oct->bootmem_desc_addr, \
+ offsetof(struct cvmx_bootmem_desc, field), \
+ SIZEOF_FIELD(struct cvmx_bootmem_desc, field))
+
+#define __cvmx_bootmem_lock(flags)
+#define __cvmx_bootmem_unlock(flags)
+
+/**
+ * This macro returns a member of the
+ * cvmx_bootmem_named_block_desc structure. These members can't
+ * be directly addressed as they might be in memory not directly
+ * reachable. In the case where bootmem is compiled with
+ * LINUX_HOST, the structure itself might be located on a remote
+ * Octeon. The argument "field" is the member name of the
+ * cvmx_bootmem_named_block_desc to read. Regardless of the type
+ * of the field, the return type is always a u64. The "addr"
+ * parameter is the physical address of the structure.
+ */
+#define CVMX_BOOTMEM_NAMED_GET_FIELD(oct, addr, field) \
+ __cvmx_bootmem_desc_get(oct, addr, \
+ offsetof(struct cvmx_bootmem_named_block_desc, field), \
+ SIZEOF_FIELD(struct cvmx_bootmem_named_block_desc, field))
+
+/**
+ * This function is the implementation of the get macros defined
+ * for individual structure members. The argument are generated
+ * by the macros inorder to read only the needed memory.
+ *
+ * @param oct Pointer to current octeon device
+ * @param base 64bit physical address of the complete structure
+ * @param offset Offset from the beginning of the structure to the member being
+ * accessed.
+ * @param size Size of the structure member.
+ *
+ * @return Value of the structure member promoted into a u64.
+ */
+static inline u64 __cvmx_bootmem_desc_get(struct octeon_device *oct,
+ u64 base,
+ u32 offset,
+ u32 size)
+{
+ base = (1ull << 63) | (base + offset);
+ switch (size) {
+ case 4:
+ return octeon_read_device_mem32(oct, base);
+ case 8:
+ return octeon_read_device_mem64(oct, base);
+ default:
+ return 0;
+ }
+}
+
+/**
+ * This function retrieves the string name of a named block. It is
+ * more complicated than a simple memcpy() since the named block
+ * descriptor may not be directly accessible.
+ *
+ * @param addr Physical address of the named block descriptor
+ * @param str String to receive the named block string name
+ * @param len Length of the string buffer, which must match the length
+ * stored in the bootmem descriptor.
+ */
+static void CVMX_BOOTMEM_NAMED_GET_NAME(struct octeon_device *oct,
+ u64 addr,
+ char *str,
+ u32 len)
+{
+ addr += offsetof(struct cvmx_bootmem_named_block_desc, name);
+ octeon_pci_read_core_mem(oct, addr, str, len);
+ str[len] = 0;
+}
+
+/* See header file for descriptions of functions */
+
+/**
+ * Check the version information on the bootmem descriptor
+ *
+ * @param exact_match
+ * Exact major version to check against. A zero means
+ * check that the version supports named blocks.
+ *
+ * @return Zero if the version is correct. Negative if the version is
+ * incorrect. Failures also cause a message to be displayed.
+ */
+static int __cvmx_bootmem_check_version(struct octeon_device *oct,
+ u32 exact_match)
+{
+ u32 major_version;
+ u32 minor_version;
+
+ if (!oct->bootmem_desc_addr)
+ oct->bootmem_desc_addr =
+ octeon_read_device_mem64(oct,
+ BOOTLOADER_PCI_READ_DESC_ADDR);
+ major_version =
+ (u32)CVMX_BOOTMEM_DESC_GET_FIELD(oct, major_version);
+ minor_version =
+ (u32)CVMX_BOOTMEM_DESC_GET_FIELD(oct, minor_version);
+ dev_dbg(&oct->pci_dev->dev, "%s: major_version=%d\n", __func__,
+ major_version);
+ if ((major_version > 3) ||
+ (exact_match && major_version != exact_match)) {
+ dev_err(&oct->pci_dev->dev, "bootmem ver mismatch %d.%d addr:0x%llx\n",
+ major_version, minor_version,
+ CAST_ULL(oct->bootmem_desc_addr));
+ return -1;
+ } else {
+ return 0;
+ }
+}
+
+static const struct cvmx_bootmem_named_block_desc
+*__cvmx_bootmem_find_named_block_flags(struct octeon_device *oct,
+ const char *name, u32 flags)
+{
+ struct cvmx_bootmem_named_block_desc *desc =
+ &oct->bootmem_named_block_desc;
+ u64 named_addr = cvmx_bootmem_phy_named_block_find(oct, name, flags);
+
+ if (named_addr) {
+ desc->base_addr = CVMX_BOOTMEM_NAMED_GET_FIELD(oct, named_addr,
+ base_addr);
+ desc->size =
+ CVMX_BOOTMEM_NAMED_GET_FIELD(oct, named_addr, size);
+ strncpy(desc->name, name, sizeof(desc->name));
+ desc->name[sizeof(desc->name) - 1] = 0;
+ return &oct->bootmem_named_block_desc;
+ } else {
+ return NULL;
+ }
+}
+
+static u64 cvmx_bootmem_phy_named_block_find(struct octeon_device *oct,
+ const char *name,
+ u32 flags)
+{
+ u64 result = 0;
+
+ __cvmx_bootmem_lock(flags);
+ if (!__cvmx_bootmem_check_version(oct, 3)) {
+ u32 i;
+ u64 named_block_array_addr =
+ CVMX_BOOTMEM_DESC_GET_FIELD(oct,
+ named_block_array_addr);
+ u32 num_blocks = (u32)
+ CVMX_BOOTMEM_DESC_GET_FIELD(oct, nb_num_blocks);
+ u32 name_length = (u32)
+ CVMX_BOOTMEM_DESC_GET_FIELD(oct, named_block_name_len);
+ u64 named_addr = named_block_array_addr;
+
+ for (i = 0; i < num_blocks; i++) {
+ u64 named_size =
+ CVMX_BOOTMEM_NAMED_GET_FIELD(oct, named_addr,
+ size);
+ if (name && named_size) {
+ char *name_tmp =
+ kmalloc(name_length + 1, GFP_KERNEL);
+ CVMX_BOOTMEM_NAMED_GET_NAME(oct, named_addr,
+ name_tmp,
+ name_length);
+ if (!strncmp(name, name_tmp, name_length)) {
+ result = named_addr;
+ kfree(name_tmp);
+ break;
+ }
+ kfree(name_tmp);
+ } else if (!name && !named_size) {
+ result = named_addr;
+ break;
+ }
+
+ named_addr +=
+ sizeof(struct cvmx_bootmem_named_block_desc);
+ }
+ }
+ __cvmx_bootmem_unlock(flags);
+ return result;
+}
+
+/**
+ * Find a named block on the remote Octeon
+ *
+ * @param name Name of block to find
+ * @param base_addr Address the block is at (OUTPUT)
+ * @param size The size of the block (OUTPUT)
+ *
+ * @return Zero on success, One on failure.
+ */
+static int octeon_named_block_find(struct octeon_device *oct, const char *name,
+ u64 *base_addr, u64 *size)
+{
+ const struct cvmx_bootmem_named_block_desc *named_block;
+
+ octeon_remote_lock();
+ named_block = __cvmx_bootmem_find_named_block_flags(oct, name, 0);
+ octeon_remote_unlock();
+ if (named_block) {
+ *base_addr = named_block->base_addr;
+ *size = named_block->size;
+ return 0;
+ }
+ return 1;
+}
+
+static void octeon_remote_lock(void)
+{
+ /* fill this in if any sharing is needed */
+}
+
+static void octeon_remote_unlock(void)
+{
+ /* fill this in if any sharing is needed */
+}
+
+int octeon_console_send_cmd(struct octeon_device *oct, char *cmd_str,
+ u32 wait_hundredths)
+{
+ u32 len = strlen(cmd_str);
+
+ dev_dbg(&oct->pci_dev->dev, "sending \"%s\" to bootloader\n", cmd_str);
+
+ if (len > BOOTLOADER_PCI_WRITE_BUFFER_STR_LEN - 1) {
+ dev_err(&oct->pci_dev->dev, "Command string too long, max length is: %d\n",
+ BOOTLOADER_PCI_WRITE_BUFFER_STR_LEN - 1);
+ return -1;
+ }
+
+ if (octeon_wait_for_bootloader(oct, wait_hundredths) != 0) {
+ dev_err(&oct->pci_dev->dev, "Bootloader not ready for command.\n");
+ return -1;
+ }
+
+ /* Write command to bootloader */
+ octeon_remote_lock();
+ octeon_pci_write_core_mem(oct, BOOTLOADER_PCI_READ_BUFFER_DATA_ADDR,
+ (u8 *)cmd_str, len);
+ octeon_write_device_mem32(oct, BOOTLOADER_PCI_READ_BUFFER_LEN_ADDR,
+ len);
+ octeon_write_device_mem32(oct, BOOTLOADER_PCI_READ_BUFFER_OWNER_ADDR,
+ OCTEON_PCI_IO_BUF_OWNER_OCTEON);
+
+ /* Bootloader should accept command very quickly
+ * if it really was ready
+ */
+ if (octeon_wait_for_bootloader(oct, 200) != 0) {
+ octeon_remote_unlock();
+ dev_err(&oct->pci_dev->dev, "Bootloader did not accept command.\n");
+ return -1;
+ }
+ octeon_remote_unlock();
+ return 0;
+}
+
+int octeon_wait_for_bootloader(struct octeon_device *oct,
+ u32 wait_time_hundredths)
+{
+ dev_dbg(&oct->pci_dev->dev, "waiting %d0 ms for bootloader\n",
+ wait_time_hundredths);
+
+ if (octeon_mem_access_ok(oct))
+ return -1;
+
+ while (wait_time_hundredths > 0 &&
+ octeon_read_device_mem32(oct,
+ BOOTLOADER_PCI_READ_BUFFER_OWNER_ADDR)
+ != OCTEON_PCI_IO_BUF_OWNER_HOST) {
+ if (--wait_time_hundredths <= 0)
+ return -1;
+ schedule_timeout_uninterruptible(HZ / 100);
+ }
+ return 0;
+}
+
+static void octeon_console_handle_result(struct octeon_device *oct,
+ size_t console_num,
+ char *buffer, s32 bytes_read)
+{
+ struct octeon_console *console;
+
+ console = &oct->console[console_num];
+
+ console->waiting = 0;
+}
+
+static char console_buffer[OCTEON_CONSOLE_MAX_READ_BYTES];
+
+static void output_console_line(struct octeon_device *oct,
+ struct octeon_console *console,
+ size_t console_num,
+ char *console_buffer,
+ s32 bytes_read)
+{
+ char *line;
+ s32 i;
+
+ line = console_buffer;
+ for (i = 0; i < bytes_read; i++) {
+ /* Output a line at a time, prefixed */
+ if (console_buffer[i] == '\n') {
+ console_buffer[i] = '\0';
+ if (console->leftover[0]) {
+ dev_info(&oct->pci_dev->dev, "%lu: %s%s\n",
+ console_num, console->leftover,
+ line);
+ console->leftover[0] = '\0';
+ } else {
+ dev_info(&oct->pci_dev->dev, "%lu: %s\n",
+ console_num, line);
+ }
+ line = &console_buffer[i + 1];
+ }
+ }
+
+ /* Save off any leftovers */
+ if (line != &console_buffer[bytes_read]) {
+ console_buffer[bytes_read] = '\0';
+ strcpy(console->leftover, line);
+ }
+}
+
+static void check_console(struct work_struct *work)
+{
+ s32 bytes_read, tries, total_read;
+ struct octeon_console *console;
+ struct cavium_wk *wk = (struct cavium_wk *)work;
+ struct octeon_device *oct = (struct octeon_device *)wk->ctxptr;
+ size_t console_num = wk->ctxul;
+ u32 delay;
+
+ console = &oct->console[console_num];
+ tries = 0;
+ total_read = 0;
+
+ do {
+ /* Take console output regardless of whether it will
+ * be logged
+ */
+ bytes_read =
+ octeon_console_read(oct, console_num, console_buffer,
+ sizeof(console_buffer) - 1, 0);
+ if (bytes_read > 0) {
+ total_read += bytes_read;
+ if (console->waiting) {
+ octeon_console_handle_result(oct, console_num,
+ console_buffer,
+ bytes_read);
+ }
+ if (octeon_console_debug_enabled(console_num)) {
+ output_console_line(oct, console, console_num,
+ console_buffer, bytes_read);
+ }
+ } else if (bytes_read < 0) {
+ dev_err(&oct->pci_dev->dev, "Error reading console %lu, ret=%d\n",
+ console_num, bytes_read);
+ }
+
+ tries++;
+ } while ((bytes_read > 0) && (tries < 16));
+
+ /* If nothing is read after polling the console,
+ * output any leftovers if any
+ */
+ if (octeon_console_debug_enabled(console_num) &&
+ (total_read == 0) && (console->leftover[0])) {
+ dev_info(&oct->pci_dev->dev, "%lu: %s\n",
+ console_num, console->leftover);
+ console->leftover[0] = '\0';
+ }
+
+ delay = OCTEON_CONSOLE_POLL_INTERVAL_MS;
+
+ schedule_delayed_work(&wk->work, msecs_to_jiffies(delay));
+}
+
+int octeon_init_consoles(struct octeon_device *oct)
+{
+ int ret = 0;
+ u64 addr, size;
+
+ ret = octeon_mem_access_ok(oct);
+ if (ret) {
+ dev_err(&oct->pci_dev->dev, "Memory access not okay'\n");
+ return ret;
+ }
+
+ ret = octeon_named_block_find(oct, OCTEON_PCI_CONSOLE_BLOCK_NAME, &addr,
+ &size);
+ if (ret) {
+ dev_err(&oct->pci_dev->dev, "Could not find console '%s'\n",
+ OCTEON_PCI_CONSOLE_BLOCK_NAME);
+ return ret;
+ }
+
+ /* num_consoles > 0, is an indication that the consoles
+ * are accessible
+ */
+ oct->num_consoles = octeon_read_device_mem32(oct,
+ addr + offsetof(struct octeon_pci_console_desc,
+ num_consoles));
+ oct->console_desc_addr = addr;
+
+ dev_dbg(&oct->pci_dev->dev, "Initialized consoles. %d available\n",
+ oct->num_consoles);
+
+ return ret;
+}
+
+int octeon_add_console(struct octeon_device *oct, u32 console_num)
+{
+ int ret = 0;
+ u32 delay;
+ u64 coreaddr;
+ struct delayed_work *work;
+ struct octeon_console *console;
+
+ if (console_num >= oct->num_consoles) {
+ dev_err(&oct->pci_dev->dev,
+ "trying to read from console number %d when only 0 to %d exist\n",
+ console_num, oct->num_consoles);
+ } else {
+ console = &oct->console[console_num];
+
+ console->waiting = 0;
+
+ coreaddr = oct->console_desc_addr + console_num * 8 +
+ offsetof(struct octeon_pci_console_desc,
+ console_addr_array);
+ console->addr = octeon_read_device_mem64(oct, coreaddr);
+ coreaddr = console->addr + offsetof(struct octeon_pci_console,
+ buf_size);
+ console->buffer_size = octeon_read_device_mem32(oct, coreaddr);
+ coreaddr = console->addr + offsetof(struct octeon_pci_console,
+ input_base_addr);
+ console->input_base_addr =
+ octeon_read_device_mem64(oct, coreaddr);
+ coreaddr = console->addr + offsetof(struct octeon_pci_console,
+ output_base_addr);
+ console->output_base_addr =
+ octeon_read_device_mem64(oct, coreaddr);
+ console->leftover[0] = '\0';
+
+ work = &oct->console_poll_work[console_num].work;
+
+ INIT_DELAYED_WORK(work, check_console);
+ oct->console_poll_work[console_num].ctxptr = (void *)oct;
+ oct->console_poll_work[console_num].ctxul = console_num;
+ delay = OCTEON_CONSOLE_POLL_INTERVAL_MS;
+ schedule_delayed_work(work, msecs_to_jiffies(delay));
+
+ if (octeon_console_debug_enabled(console_num)) {
+ ret = octeon_console_send_cmd(oct,
+ "setenv pci_console_active 1",
+ 2000);
+ }
+
+ console->active = 1;
+ }
+
+ return ret;
+}
+
+/**
+ * Removes all consoles
+ *
+ * @param oct octeon device
+ */
+void octeon_remove_consoles(struct octeon_device *oct)
+{
+ u32 i;
+ struct octeon_console *console;
+
+ for (i = 0; i < oct->num_consoles; i++) {
+ console = &oct->console[i];
+
+ if (!console->active)
+ continue;
+
+ cancel_delayed_work_sync(&oct->console_poll_work[i].
+ work);
+ console->addr = 0;
+ console->buffer_size = 0;
+ console->input_base_addr = 0;
+ console->output_base_addr = 0;
+ }
+
+ oct->num_consoles = 0;
+}
+
+static inline int octeon_console_free_bytes(u32 buffer_size,
+ u32 wr_idx,
+ u32 rd_idx)
+{
+ if (rd_idx >= buffer_size || wr_idx >= buffer_size)
+ return -1;
+
+ return ((buffer_size - 1) - (wr_idx - rd_idx)) % buffer_size;
+}
+
+static inline int octeon_console_avail_bytes(u32 buffer_size,
+ u32 wr_idx,
+ u32 rd_idx)
+{
+ if (rd_idx >= buffer_size || wr_idx >= buffer_size)
+ return -1;
+
+ return buffer_size - 1 -
+ octeon_console_free_bytes(buffer_size, wr_idx, rd_idx);
+}
+
+int octeon_console_read(struct octeon_device *oct, u32 console_num,
+ char *buffer, u32 buf_size, u32 flags)
+{
+ int bytes_to_read;
+ u32 rd_idx, wr_idx;
+ struct octeon_console *console;
+
+ if (console_num >= oct->num_consoles) {
+ dev_err(&oct->pci_dev->dev, "Attempted to read from disabled console %d\n",
+ console_num);
+ return 0;
+ }
+
+ console = &oct->console[console_num];
+
+ /* Check to see if any data is available.
+ * Maybe optimize this with 64-bit read.
+ */
+ rd_idx = octeon_read_device_mem32(oct, console->addr +
+ offsetof(struct octeon_pci_console, output_read_index));
+ wr_idx = octeon_read_device_mem32(oct, console->addr +
+ offsetof(struct octeon_pci_console, output_write_index));
+
+ bytes_to_read = octeon_console_avail_bytes(console->buffer_size,
+ wr_idx, rd_idx);
+ if (bytes_to_read <= 0)
+ return bytes_to_read;
+
+ bytes_to_read = MIN(bytes_to_read, (s32)buf_size);
+
+ /* Check to see if what we want to read is not contiguous, and limit
+ * ourselves to the contiguous block
+ */
+ if (rd_idx + bytes_to_read >= console->buffer_size)
+ bytes_to_read = console->buffer_size - rd_idx;
+
+ octeon_pci_read_core_mem(oct, console->output_base_addr + rd_idx,
+ buffer, bytes_to_read);
+ octeon_write_device_mem32(oct, console->addr +
+ offsetof(struct octeon_pci_console,
+ output_read_index),
+ (rd_idx + bytes_to_read) %
+ console->buffer_size);
+
+ return bytes_to_read;
+}