diff options
Diffstat (limited to 'drivers/staging/fwserial/fwserial.h')
| -rw-r--r-- | drivers/staging/fwserial/fwserial.h | 387 |
1 files changed, 387 insertions, 0 deletions
diff --git a/drivers/staging/fwserial/fwserial.h b/drivers/staging/fwserial/fwserial.h new file mode 100644 index 000000000000..caa1c1ea82d5 --- /dev/null +++ b/drivers/staging/fwserial/fwserial.h @@ -0,0 +1,387 @@ +#ifndef _FIREWIRE_FWSERIAL_H +#define _FIREWIRE_FWSERIAL_H + +#include <linux/kernel.h> +#include <linux/tty.h> +#include <linux/tty_driver.h> +#include <linux/tty_flip.h> +#include <linux/list.h> +#include <linux/firewire.h> +#include <linux/firewire-constants.h> +#include <linux/spinlock.h> +#include <linux/rcupdate.h> +#include <linux/mutex.h> +#include <linux/serial.h> +#include <linux/serial_reg.h> +#include <linux/module.h> +#include <linux/seq_file.h> + +#include "dma_fifo.h" + +#ifdef FWTTY_PROFILING +#define DISTRIBUTION_MAX_SIZE 8192 +#define DISTRIBUTION_MAX_INDEX (ilog2(DISTRIBUTION_MAX_SIZE) + 1) +static inline void profile_size_distrib(unsigned stat[], unsigned val) +{ + int n = (val) ? min(ilog2(val) + 1, DISTRIBUTION_MAX_INDEX) : 0; + ++stat[n]; +} +#else +#define DISTRIBUTION_MAX_INDEX 0 +#define profile_size_distrib(st, n) +#endif + +/* Parameters for both VIRT_CABLE_PLUG & VIRT_CABLE_PLUG_RSP mgmt codes */ +struct virt_plug_params { + __be32 status_hi; + __be32 status_lo; + __be32 fifo_hi; + __be32 fifo_lo; + __be32 fifo_len; +}; + +struct peer_work_params { + union { + struct virt_plug_params plug_req; + }; +}; + +/** + * fwtty_peer: structure representing local & remote unit devices + * @unit: unit child device of fw_device node + * @serial: back pointer to associated fw_serial aggregate + * @guid: unique 64-bit guid for this unit device + * @generation: most recent bus generation + * @node_id: most recent node_id + * @speed: link speed of peer (0 = S100, 2 = S400, ... 5 = S3200) + * @mgmt_addr: bus addr region to write mgmt packets to + * @status_addr: bus addr register to write line status to + * @fifo_addr: bus addr region to write serial output to + * @fifo_len: max length for single write to fifo_addr + * @list: link for insertion into fw_serial's peer_list + * @rcu: for deferring peer reclamation + * @lock: spinlock to synchonize changes to state & port fields + * @work: only one work item can be queued at any one time + * Note: pending work is canceled prior to removal, so this + * peer is valid for at least the lifetime of the work function + * @work_params: parameter block for work functions + * @timer: timer for resetting peer state if remote request times out + * @state: current state + * @connect: work item for auto-connecting + * @connect_retries: # of connections already attempted + * @port: associated tty_port (usable if state == FWSC_ATTACHED) + */ +struct fwtty_peer { + struct fw_unit *unit; + struct fw_serial *serial; + u64 guid; + int generation; + int node_id; + unsigned speed; + int max_payload; + u64 mgmt_addr; + + /* these are usable only if state == FWSC_ATTACHED */ + u64 status_addr; + u64 fifo_addr; + int fifo_len; + + struct list_head list; + struct rcu_head rcu; + + spinlock_t lock; + struct work_struct work; + struct peer_work_params work_params; + struct timer_list timer; + int state; + struct delayed_work connect; + int connect_retries; + + struct fwtty_port *port; +}; + +#define to_peer(ptr, field) (container_of(ptr, struct fwtty_peer, field)) + +/* state values for fwtty_peer.state field */ +enum fwtty_peer_state { + FWPS_GONE, + FWPS_NOT_ATTACHED, + FWPS_ATTACHED, + FWPS_PLUG_PENDING, + FWPS_PLUG_RESPONDING, + FWPS_UNPLUG_PENDING, + FWPS_UNPLUG_RESPONDING, + + FWPS_NO_MGMT_ADDR = -1, +}; + +#define CONNECT_RETRY_DELAY HZ +#define MAX_CONNECT_RETRIES 10 + +/* must be holding peer lock for these state funclets */ +static inline void peer_set_state(struct fwtty_peer *peer, int new) +{ + peer->state = new; +} + +static inline struct fwtty_port *peer_revert_state(struct fwtty_peer *peer) +{ + struct fwtty_port *port = peer->port; + + peer->port = NULL; + peer_set_state(peer, FWPS_NOT_ATTACHED); + return port; +} + +struct fwserial_mgmt_pkt { + struct { + __be16 len; + __be16 code; + } hdr; + union { + struct virt_plug_params plug_req; + struct virt_plug_params plug_rsp; + }; +} __packed; + +/* fwserial_mgmt_packet codes */ +#define FWSC_RSP_OK 0x0000 +#define FWSC_RSP_NACK 0x8000 +#define FWSC_CODE_MASK 0x0fff + +#define FWSC_VIRT_CABLE_PLUG 1 +#define FWSC_VIRT_CABLE_UNPLUG 2 +#define FWSC_VIRT_CABLE_PLUG_RSP 3 +#define FWSC_VIRT_CABLE_UNPLUG_RSP 4 + +/* 1 min. plug timeout -- suitable for userland authorization */ +#define VIRT_CABLE_PLUG_TIMEOUT (60 * HZ) + +struct stats { + unsigned xchars; + unsigned dropped; + unsigned tx_stall; + unsigned fifo_errs; + unsigned sent; + unsigned lost; + unsigned throttled; + unsigned watermark; + unsigned reads[DISTRIBUTION_MAX_INDEX + 1]; + unsigned writes[DISTRIBUTION_MAX_INDEX + 1]; + unsigned txns[DISTRIBUTION_MAX_INDEX + 1]; + unsigned unthrottle[DISTRIBUTION_MAX_INDEX + 1]; +}; + +struct fwconsole_ops { + void (*notify)(int code, void *data); + void (*stats)(struct stats *stats, void *data); + void (*proc_show)(struct seq_file *m, void *data); +}; + +/* codes for console ops notify */ +#define FWCON_NOTIFY_ATTACH 1 +#define FWCON_NOTIFY_DETACH 2 + +struct buffered_rx { + struct list_head list; + size_t n; + unsigned char data[0]; +}; + +/** + * fwtty_port: structure used to track/represent underlying tty_port + * @port: underlying tty_port + * @device: tty device + * @index: index into port_table for this particular port + * note: minor = index + FWSERIAL_TTY_START_MINOR + * @serial: back pointer to the containing fw_serial + * @rx_handler: bus address handler for unique addr region used by remotes + * to communicate with this port. Every port uses + * fwtty_port_handler() for per port transactions. + * @fwcon_ops: ops for attached fw_console (if any) + * @con_data: private data for fw_console + * @wait_tx: waitqueue for sleeping until writer/drain completes tx + * @emit_breaks: delayed work responsible for generating breaks when the + * break line status is active + * @cps : characters per second computed from the termios settings + * @break_last: timestamp in jiffies from last emit_breaks + * @hangup: work responsible for HUPing when carrier is dropped/lost + * @mstatus: loose virtualization of LSR/MSR + * bits 15..0 correspond to TIOCM_* bits + * bits 19..16 reserved for mctrl + * bit 20 OOB_TX_THROTTLE + * bits 23..21 reserved + * bits 31..24 correspond to UART_LSR_* bits + * @lock: spinlock for protecting concurrent access to fields below it + * @mctrl: loose virtualization of MCR + * bits 15..0 correspond to TIOCM_* bits + * bit 16 OOB_RX_THROTTLE + * bits 19..17 reserved + * bits 31..20 reserved for mstatus + * @drain: delayed work scheduled to ensure that writes are flushed. + * The work can race with the writer but concurrent sending is + * prevented with the IN_TX flag. Scheduled under lock to + * limit scheduling when fifo has just been drained. + * @push: work responsible for pushing buffered rx to the ldisc. + * rx can become buffered if the tty buffer is filled before the + * ldisc throttles the sender. + * @buf_list: list of buffered rx yet to be sent to ldisc + * @buffered: byte count of buffered rx + * @tx_fifo: fifo used to store & block-up writes for dma to remote + * @max_payload: max bytes transmissable per dma (based on peer's max_payload) + * @status_mask: UART_LSR_* bitmask significant to rx (based on termios) + * @ignore_mask: UART_LSR_* bitmask of states to ignore (also based on termios) + * @break_ctl: if set, port is 'sending break' to remote + * @write_only: self-explanatory + * @overrun: previous rx was lost (partially or completely) + * @loopback: if set, port is in loopback mode + * @flags: atomic bit flags + * bit 0: IN_TX - gate to allow only one cpu to send from the dma fifo + * at a time. + * bit 1: STOP_TX - force tx to exit while sending + * @peer: rcu-pointer to associated fwtty_peer (if attached) + * NULL if no peer attached + * @icount: predefined statistics reported by the TIOCGICOUNT ioctl + * @stats: additional statistics reported in /proc/tty/driver/firewire_serial + */ +struct fwtty_port { + struct tty_port port; + struct device *device; + unsigned index; + struct fw_serial *serial; + struct fw_address_handler rx_handler; + + struct fwconsole_ops *fwcon_ops; + void *con_data; + + wait_queue_head_t wait_tx; + struct delayed_work emit_breaks; + unsigned cps; + unsigned long break_last; + + struct work_struct hangup; + + unsigned mstatus; + + spinlock_t lock; + unsigned mctrl; + struct delayed_work drain; + struct work_struct push; + struct list_head buf_list; + int buffered; + struct dma_fifo tx_fifo; + int max_payload; + unsigned status_mask; + unsigned ignore_mask; + unsigned break_ctl:1, + write_only:1, + overrun:1, + loopback:1; + unsigned long flags; + + struct fwtty_peer *peer; + + struct async_icount icount; + struct stats stats; +}; + +#define to_port(ptr, field) (container_of(ptr, struct fwtty_port, field)) + +/* bit #s for flags field */ +#define IN_TX 0 +#define STOP_TX 1 +#define BUFFERING_RX 2 + +/* bitmasks for special mctrl/mstatus bits */ +#define OOB_RX_THROTTLE 0x00010000 +#define MCTRL_RSRVD 0x000e0000 +#define OOB_TX_THROTTLE 0x00100000 +#define MSTATUS_RSRVD 0x00e00000 + +#define MCTRL_MASK (TIOCM_DTR | TIOCM_RTS | TIOCM_OUT1 | TIOCM_OUT2 | \ + TIOCM_LOOP | OOB_RX_THROTTLE | MCTRL_RSRVD) + +/* XXX even every 1/50th secs. may be unnecessarily accurate */ +/* delay in jiffies between brk emits */ +#define FREQ_BREAKS (HZ / 50) + +/* Ports are allocated in blocks of num_ports for each fw_card */ +#define MAX_CARD_PORTS 32 /* max # of ports per card */ +#define MAX_TOTAL_PORTS 64 /* max # of ports total */ + +/* tuning parameters */ +#define FWTTY_PORT_TXFIFO_LEN 4096 +#define FWTTY_PORT_MAX_PEND_DMA 8 /* costs a cache line per pend */ +#define DRAIN_THRESHOLD 1024 +#define MAX_ASYNC_PAYLOAD 4096 /* ohci-defined limit */ +#define WRITER_MINIMUM 128 +/* TODO: how to set watermark to AR context size? see fwtty_rx() */ +#define HIGH_WATERMARK 32768 /* AR context is 32K */ + +/* + * Size of bus addr region above 4GB used per port as the recv addr + * - must be at least as big as the MAX_ASYNC_PAYLOAD + */ +#define FWTTY_PORT_RXFIFO_LEN MAX_ASYNC_PAYLOAD + +/** + * fw_serial: aggregate used to associate tty ports with specific fw_card + * @card: fw_card associated with this fw_serial device (1:1 association) + * @kref: reference-counted multi-port management allows delayed destroy + * @self: local unit device as 'peer'. Not valid until local unit device + * is enumerated. + * @list: link for insertion into fwserial_list + * @peer_list: list of local & remote unit devices attached to this card + * @ports: fixed array of tty_ports provided by this serial device + */ +struct fw_serial { + struct fw_card *card; + struct kref kref; + + struct fwtty_peer *self; + + struct list_head list; + struct list_head peer_list; + + struct fwtty_port *ports[MAX_CARD_PORTS]; +}; + +#define to_serial(ptr, field) (container_of(ptr, struct fw_serial, field)) + +#define TTY_DEV_NAME "fwtty" /* ttyFW was taken */ +static const char tty_dev_name[] = TTY_DEV_NAME; +static const char loop_dev_name[] = "fwloop"; +extern bool limit_bw; + +struct tty_driver *fwtty_driver; + +#define driver_err(s, v...) pr_err(KBUILD_MODNAME ": " s, ##v) + +struct fwtty_port *fwtty_port_get(unsigned index); +void fwtty_port_put(struct fwtty_port *port); + +static inline void fwtty_bind_console(struct fwtty_port *port, + struct fwconsole_ops *fwcon_ops, + void *data) +{ + port->con_data = data; + port->fwcon_ops = fwcon_ops; +} + +/* + * Returns the max send async payload size in bytes based on the unit device + * link speed - if set to limit bandwidth to max 20%, use lookup table + */ +static inline int link_speed_to_max_payload(unsigned speed) +{ + static const int max_async[] = { 307, 614, 1229, 2458, }; + BUILD_BUG_ON(ARRAY_SIZE(max_async) - 1 != SCODE_800); + + speed = clamp(speed, (unsigned) SCODE_100, (unsigned) SCODE_800); + if (limit_bw) + return max_async[speed]; + else + return 1 << (speed + 9); +} + +#endif /* _FIREWIRE_FWSERIAL_H */ |