+++ /dev/null
-/*
- * Copyright (C) 2004 Hollis Blanchard <hollisb@us.ibm.com>, IBM
- *
- * 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; either version 2 of the License, or
- * (at your option) any later version.
- *
- * 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. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- */
-
-/* Host Virtual Serial Interface (HVSI) is a protocol between the hosted OS
- * and the service processor on IBM pSeries servers. On these servers, there
- * are no serial ports under the OS's control, and sometimes there is no other
- * console available either. However, the service processor has two standard
- * serial ports, so this over-complicated protocol allows the OS to control
- * those ports by proxy.
- *
- * Besides data, the procotol supports the reading/writing of the serial
- * port's DTR line, and the reading of the CD line. This is to allow the OS to
- * control a modem attached to the service processor's serial port. Note that
- * the OS cannot change the speed of the port through this protocol.
- */
-
-#undef DEBUG
-
-#include <linux/console.h>
-#include <linux/ctype.h>
-#include <linux/delay.h>
-#include <linux/init.h>
-#include <linux/interrupt.h>
-#include <linux/module.h>
-#include <linux/major.h>
-#include <linux/kernel.h>
-#include <linux/spinlock.h>
-#include <linux/sysrq.h>
-#include <linux/tty.h>
-#include <linux/tty_flip.h>
-#include <asm/hvcall.h>
-#include <asm/hvconsole.h>
-#include <asm/prom.h>
-#include <asm/uaccess.h>
-#include <asm/vio.h>
-#include <asm/param.h>
-
-#define HVSI_MAJOR 229
-#define HVSI_MINOR 128
-#define MAX_NR_HVSI_CONSOLES 4
-
-#define HVSI_TIMEOUT (5*HZ)
-#define HVSI_VERSION 1
-#define HVSI_MAX_PACKET 256
-#define HVSI_MAX_READ 16
-#define HVSI_MAX_OUTGOING_DATA 12
-#define N_OUTBUF 12
-
-/*
- * we pass data via two 8-byte registers, so we would like our char arrays
- * properly aligned for those loads.
- */
-#define __ALIGNED__ __attribute__((__aligned__(sizeof(long))))
-
-struct hvsi_struct {
- struct delayed_work writer;
- struct work_struct handshaker;
- wait_queue_head_t emptyq; /* woken when outbuf is emptied */
- wait_queue_head_t stateq; /* woken when HVSI state changes */
- spinlock_t lock;
- int index;
- struct tty_struct *tty;
- int count;
- uint8_t throttle_buf[128];
- uint8_t outbuf[N_OUTBUF]; /* to implement write_room and chars_in_buffer */
- /* inbuf is for packet reassembly. leave a little room for leftovers. */
- uint8_t inbuf[HVSI_MAX_PACKET + HVSI_MAX_READ];
- uint8_t *inbuf_end;
- int n_throttle;
- int n_outbuf;
- uint32_t vtermno;
- uint32_t virq;
- atomic_t seqno; /* HVSI packet sequence number */
- uint16_t mctrl;
- uint8_t state; /* HVSI protocol state */
- uint8_t flags;
-#ifdef CONFIG_MAGIC_SYSRQ
- uint8_t sysrq;
-#endif /* CONFIG_MAGIC_SYSRQ */
-};
-static struct hvsi_struct hvsi_ports[MAX_NR_HVSI_CONSOLES];
-
-static struct tty_driver *hvsi_driver;
-static int hvsi_count;
-static int (*hvsi_wait)(struct hvsi_struct *hp, int state);
-
-enum HVSI_PROTOCOL_STATE {
- HVSI_CLOSED,
- HVSI_WAIT_FOR_VER_RESPONSE,
- HVSI_WAIT_FOR_VER_QUERY,
- HVSI_OPEN,
- HVSI_WAIT_FOR_MCTRL_RESPONSE,
- HVSI_FSP_DIED,
-};
-#define HVSI_CONSOLE 0x1
-
-#define VS_DATA_PACKET_HEADER 0xff
-#define VS_CONTROL_PACKET_HEADER 0xfe
-#define VS_QUERY_PACKET_HEADER 0xfd
-#define VS_QUERY_RESPONSE_PACKET_HEADER 0xfc
-
-/* control verbs */
-#define VSV_SET_MODEM_CTL 1 /* to service processor only */
-#define VSV_MODEM_CTL_UPDATE 2 /* from service processor only */
-#define VSV_CLOSE_PROTOCOL 3
-
-/* query verbs */
-#define VSV_SEND_VERSION_NUMBER 1
-#define VSV_SEND_MODEM_CTL_STATUS 2
-
-/* yes, these masks are not consecutive. */
-#define HVSI_TSDTR 0x01
-#define HVSI_TSCD 0x20
-
-struct hvsi_header {
- uint8_t type;
- uint8_t len;
- uint16_t seqno;
-} __attribute__((packed));
-
-struct hvsi_data {
- uint8_t type;
- uint8_t len;
- uint16_t seqno;
- uint8_t data[HVSI_MAX_OUTGOING_DATA];
-} __attribute__((packed));
-
-struct hvsi_control {
- uint8_t type;
- uint8_t len;
- uint16_t seqno;
- uint16_t verb;
- /* optional depending on verb: */
- uint32_t word;
- uint32_t mask;
-} __attribute__((packed));
-
-struct hvsi_query {
- uint8_t type;
- uint8_t len;
- uint16_t seqno;
- uint16_t verb;
-} __attribute__((packed));
-
-struct hvsi_query_response {
- uint8_t type;
- uint8_t len;
- uint16_t seqno;
- uint16_t verb;
- uint16_t query_seqno;
- union {
- uint8_t version;
- uint32_t mctrl_word;
- } u;
-} __attribute__((packed));
-
-
-
-static inline int is_console(struct hvsi_struct *hp)
-{
- return hp->flags & HVSI_CONSOLE;
-}
-
-static inline int is_open(struct hvsi_struct *hp)
-{
- /* if we're waiting for an mctrl then we're already open */
- return (hp->state == HVSI_OPEN)
- || (hp->state == HVSI_WAIT_FOR_MCTRL_RESPONSE);
-}
-
-static inline void print_state(struct hvsi_struct *hp)
-{
-#ifdef DEBUG
- static const char *state_names[] = {
- "HVSI_CLOSED",
- "HVSI_WAIT_FOR_VER_RESPONSE",
- "HVSI_WAIT_FOR_VER_QUERY",
- "HVSI_OPEN",
- "HVSI_WAIT_FOR_MCTRL_RESPONSE",
- "HVSI_FSP_DIED",
- };
- const char *name = (hp->state < ARRAY_SIZE(state_names))
- ? state_names[hp->state] : "UNKNOWN";
-
- pr_debug("hvsi%i: state = %s\n", hp->index, name);
-#endif /* DEBUG */
-}
-
-static inline void __set_state(struct hvsi_struct *hp, int state)
-{
- hp->state = state;
- print_state(hp);
- wake_up_all(&hp->stateq);
-}
-
-static inline void set_state(struct hvsi_struct *hp, int state)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&hp->lock, flags);
- __set_state(hp, state);
- spin_unlock_irqrestore(&hp->lock, flags);
-}
-
-static inline int len_packet(const uint8_t *packet)
-{
- return (int)((struct hvsi_header *)packet)->len;
-}
-
-static inline int is_header(const uint8_t *packet)
-{
- struct hvsi_header *header = (struct hvsi_header *)packet;
- return header->type >= VS_QUERY_RESPONSE_PACKET_HEADER;
-}
-
-static inline int got_packet(const struct hvsi_struct *hp, uint8_t *packet)
-{
- if (hp->inbuf_end < packet + sizeof(struct hvsi_header))
- return 0; /* don't even have the packet header */
-
- if (hp->inbuf_end < (packet + len_packet(packet)))
- return 0; /* don't have the rest of the packet */
-
- return 1;
-}
-
-/* shift remaining bytes in packetbuf down */
-static void compact_inbuf(struct hvsi_struct *hp, uint8_t *read_to)
-{
- int remaining = (int)(hp->inbuf_end - read_to);
-
- pr_debug("%s: %i chars remain\n", __func__, remaining);
-
- if (read_to != hp->inbuf)
- memmove(hp->inbuf, read_to, remaining);
-
- hp->inbuf_end = hp->inbuf + remaining;
-}
-
-#ifdef DEBUG
-#define dbg_dump_packet(packet) dump_packet(packet)
-#define dbg_dump_hex(data, len) dump_hex(data, len)
-#else
-#define dbg_dump_packet(packet) do { } while (0)
-#define dbg_dump_hex(data, len) do { } while (0)
-#endif
-
-static void dump_hex(const uint8_t *data, int len)
-{
- int i;
-
- printk(" ");
- for (i=0; i < len; i++)
- printk("%.2x", data[i]);
-
- printk("\n ");
- for (i=0; i < len; i++) {
- if (isprint(data[i]))
- printk("%c", data[i]);
- else
- printk(".");
- }
- printk("\n");
-}
-
-static void dump_packet(uint8_t *packet)
-{
- struct hvsi_header *header = (struct hvsi_header *)packet;
-
- printk("type 0x%x, len %i, seqno %i:\n", header->type, header->len,
- header->seqno);
-
- dump_hex(packet, header->len);
-}
-
-static int hvsi_read(struct hvsi_struct *hp, char *buf, int count)
-{
- unsigned long got;
-
- got = hvc_get_chars(hp->vtermno, buf, count);
-
- return got;
-}
-
-static void hvsi_recv_control(struct hvsi_struct *hp, uint8_t *packet,
- struct tty_struct **to_hangup, struct hvsi_struct **to_handshake)
-{
- struct hvsi_control *header = (struct hvsi_control *)packet;
-
- switch (header->verb) {
- case VSV_MODEM_CTL_UPDATE:
- if ((header->word & HVSI_TSCD) == 0) {
- /* CD went away; no more connection */
- pr_debug("hvsi%i: CD dropped\n", hp->index);
- hp->mctrl &= TIOCM_CD;
- /* If userland hasn't done an open(2) yet, hp->tty is NULL. */
- if (hp->tty && !(hp->tty->flags & CLOCAL))
- *to_hangup = hp->tty;
- }
- break;
- case VSV_CLOSE_PROTOCOL:
- pr_debug("hvsi%i: service processor came back\n", hp->index);
- if (hp->state != HVSI_CLOSED) {
- *to_handshake = hp;
- }
- break;
- default:
- printk(KERN_WARNING "hvsi%i: unknown HVSI control packet: ",
- hp->index);
- dump_packet(packet);
- break;
- }
-}
-
-static void hvsi_recv_response(struct hvsi_struct *hp, uint8_t *packet)
-{
- struct hvsi_query_response *resp = (struct hvsi_query_response *)packet;
-
- switch (hp->state) {
- case HVSI_WAIT_FOR_VER_RESPONSE:
- __set_state(hp, HVSI_WAIT_FOR_VER_QUERY);
- break;
- case HVSI_WAIT_FOR_MCTRL_RESPONSE:
- hp->mctrl = 0;
- if (resp->u.mctrl_word & HVSI_TSDTR)
- hp->mctrl |= TIOCM_DTR;
- if (resp->u.mctrl_word & HVSI_TSCD)
- hp->mctrl |= TIOCM_CD;
- __set_state(hp, HVSI_OPEN);
- break;
- default:
- printk(KERN_ERR "hvsi%i: unexpected query response: ", hp->index);
- dump_packet(packet);
- break;
- }
-}
-
-/* respond to service processor's version query */
-static int hvsi_version_respond(struct hvsi_struct *hp, uint16_t query_seqno)
-{
- struct hvsi_query_response packet __ALIGNED__;
- int wrote;
-
- packet.type = VS_QUERY_RESPONSE_PACKET_HEADER;
- packet.len = sizeof(struct hvsi_query_response);
- packet.seqno = atomic_inc_return(&hp->seqno);
- packet.verb = VSV_SEND_VERSION_NUMBER;
- packet.u.version = HVSI_VERSION;
- packet.query_seqno = query_seqno+1;
-
- pr_debug("%s: sending %i bytes\n", __func__, packet.len);
- dbg_dump_hex((uint8_t*)&packet, packet.len);
-
- wrote = hvc_put_chars(hp->vtermno, (char *)&packet, packet.len);
- if (wrote != packet.len) {
- printk(KERN_ERR "hvsi%i: couldn't send query response!\n",
- hp->index);
- return -EIO;
- }
-
- return 0;
-}
-
-static void hvsi_recv_query(struct hvsi_struct *hp, uint8_t *packet)
-{
- struct hvsi_query *query = (struct hvsi_query *)packet;
-
- switch (hp->state) {
- case HVSI_WAIT_FOR_VER_QUERY:
- hvsi_version_respond(hp, query->seqno);
- __set_state(hp, HVSI_OPEN);
- break;
- default:
- printk(KERN_ERR "hvsi%i: unexpected query: ", hp->index);
- dump_packet(packet);
- break;
- }
-}
-
-static void hvsi_insert_chars(struct hvsi_struct *hp, const char *buf, int len)
-{
- int i;
-
- for (i=0; i < len; i++) {
- char c = buf[i];
-#ifdef CONFIG_MAGIC_SYSRQ
- if (c == '\0') {
- hp->sysrq = 1;
- continue;
- } else if (hp->sysrq) {
- handle_sysrq(c);
- hp->sysrq = 0;
- continue;
- }
-#endif /* CONFIG_MAGIC_SYSRQ */
- tty_insert_flip_char(hp->tty, c, 0);
- }
-}
-
-/*
- * We could get 252 bytes of data at once here. But the tty layer only
- * throttles us at TTY_THRESHOLD_THROTTLE (128) bytes, so we could overflow
- * it. Accordingly we won't send more than 128 bytes at a time to the flip
- * buffer, which will give the tty buffer a chance to throttle us. Should the
- * value of TTY_THRESHOLD_THROTTLE change in n_tty.c, this code should be
- * revisited.
- */
-#define TTY_THRESHOLD_THROTTLE 128
-static struct tty_struct *hvsi_recv_data(struct hvsi_struct *hp,
- const uint8_t *packet)
-{
- const struct hvsi_header *header = (const struct hvsi_header *)packet;
- const uint8_t *data = packet + sizeof(struct hvsi_header);
- int datalen = header->len - sizeof(struct hvsi_header);
- int overflow = datalen - TTY_THRESHOLD_THROTTLE;
-
- pr_debug("queueing %i chars '%.*s'\n", datalen, datalen, data);
-
- if (datalen == 0)
- return NULL;
-
- if (overflow > 0) {
- pr_debug("%s: got >TTY_THRESHOLD_THROTTLE bytes\n", __func__);
- datalen = TTY_THRESHOLD_THROTTLE;
- }
-
- hvsi_insert_chars(hp, data, datalen);
-
- if (overflow > 0) {
- /*
- * we still have more data to deliver, so we need to save off the
- * overflow and send it later
- */
- pr_debug("%s: deferring overflow\n", __func__);
- memcpy(hp->throttle_buf, data + TTY_THRESHOLD_THROTTLE, overflow);
- hp->n_throttle = overflow;
- }
-
- return hp->tty;
-}
-
-/*
- * Returns true/false indicating data successfully read from hypervisor.
- * Used both to get packets for tty connections and to advance the state
- * machine during console handshaking (in which case tty = NULL and we ignore
- * incoming data).
- */
-static int hvsi_load_chunk(struct hvsi_struct *hp, struct tty_struct **flip,
- struct tty_struct **hangup, struct hvsi_struct **handshake)
-{
- uint8_t *packet = hp->inbuf;
- int chunklen;
-
- *flip = NULL;
- *hangup = NULL;
- *handshake = NULL;
-
- chunklen = hvsi_read(hp, hp->inbuf_end, HVSI_MAX_READ);
- if (chunklen == 0) {
- pr_debug("%s: 0-length read\n", __func__);
- return 0;
- }
-
- pr_debug("%s: got %i bytes\n", __func__, chunklen);
- dbg_dump_hex(hp->inbuf_end, chunklen);
-
- hp->inbuf_end += chunklen;
-
- /* handle all completed packets */
- while ((packet < hp->inbuf_end) && got_packet(hp, packet)) {
- struct hvsi_header *header = (struct hvsi_header *)packet;
-
- if (!is_header(packet)) {
- printk(KERN_ERR "hvsi%i: got malformed packet\n", hp->index);
- /* skip bytes until we find a header or run out of data */
- while ((packet < hp->inbuf_end) && (!is_header(packet)))
- packet++;
- continue;
- }
-
- pr_debug("%s: handling %i-byte packet\n", __func__,
- len_packet(packet));
- dbg_dump_packet(packet);
-
- switch (header->type) {
- case VS_DATA_PACKET_HEADER:
- if (!is_open(hp))
- break;
- if (hp->tty == NULL)
- break; /* no tty buffer to put data in */
- *flip = hvsi_recv_data(hp, packet);
- break;
- case VS_CONTROL_PACKET_HEADER:
- hvsi_recv_control(hp, packet, hangup, handshake);
- break;
- case VS_QUERY_RESPONSE_PACKET_HEADER:
- hvsi_recv_response(hp, packet);
- break;
- case VS_QUERY_PACKET_HEADER:
- hvsi_recv_query(hp, packet);
- break;
- default:
- printk(KERN_ERR "hvsi%i: unknown HVSI packet type 0x%x\n",
- hp->index, header->type);
- dump_packet(packet);
- break;
- }
-
- packet += len_packet(packet);
-
- if (*hangup || *handshake) {
- pr_debug("%s: hangup or handshake\n", __func__);
- /*
- * we need to send the hangup now before receiving any more data.
- * If we get "data, hangup, data", we can't deliver the second
- * data before the hangup.
- */
- break;
- }
- }
-
- compact_inbuf(hp, packet);
-
- return 1;
-}
-
-static void hvsi_send_overflow(struct hvsi_struct *hp)
-{
- pr_debug("%s: delivering %i bytes overflow\n", __func__,
- hp->n_throttle);
-
- hvsi_insert_chars(hp, hp->throttle_buf, hp->n_throttle);
- hp->n_throttle = 0;
-}
-
-/*
- * must get all pending data because we only get an irq on empty->non-empty
- * transition
- */
-static irqreturn_t hvsi_interrupt(int irq, void *arg)
-{
- struct hvsi_struct *hp = (struct hvsi_struct *)arg;
- struct tty_struct *flip;
- struct tty_struct *hangup;
- struct hvsi_struct *handshake;
- unsigned long flags;
- int again = 1;
-
- pr_debug("%s\n", __func__);
-
- while (again) {
- spin_lock_irqsave(&hp->lock, flags);
- again = hvsi_load_chunk(hp, &flip, &hangup, &handshake);
- spin_unlock_irqrestore(&hp->lock, flags);
-
- /*
- * we have to call tty_flip_buffer_push() and tty_hangup() outside our
- * spinlock. But we also have to keep going until we've read all the
- * available data.
- */
-
- if (flip) {
- /* there was data put in the tty flip buffer */
- tty_flip_buffer_push(flip);
- flip = NULL;
- }
-
- if (hangup) {
- tty_hangup(hangup);
- }
-
- if (handshake) {
- pr_debug("hvsi%i: attempting re-handshake\n", handshake->index);
- schedule_work(&handshake->handshaker);
- }
- }
-
- spin_lock_irqsave(&hp->lock, flags);
- if (hp->tty && hp->n_throttle
- && (!test_bit(TTY_THROTTLED, &hp->tty->flags))) {
- /* we weren't hung up and we weren't throttled, so we can deliver the
- * rest now */
- flip = hp->tty;
- hvsi_send_overflow(hp);
- }
- spin_unlock_irqrestore(&hp->lock, flags);
-
- if (flip) {
- tty_flip_buffer_push(flip);
- }
-
- return IRQ_HANDLED;
-}
-
-/* for boot console, before the irq handler is running */
-static int __init poll_for_state(struct hvsi_struct *hp, int state)
-{
- unsigned long end_jiffies = jiffies + HVSI_TIMEOUT;
-
- for (;;) {
- hvsi_interrupt(hp->virq, (void *)hp); /* get pending data */
-
- if (hp->state == state)
- return 0;
-
- mdelay(5);
- if (time_after(jiffies, end_jiffies))
- return -EIO;
- }
-}
-
-/* wait for irq handler to change our state */
-static int wait_for_state(struct hvsi_struct *hp, int state)
-{
- int ret = 0;
-
- if (!wait_event_timeout(hp->stateq, (hp->state == state), HVSI_TIMEOUT))
- ret = -EIO;
-
- return ret;
-}
-
-static int hvsi_query(struct hvsi_struct *hp, uint16_t verb)
-{
- struct hvsi_query packet __ALIGNED__;
- int wrote;
-
- packet.type = VS_QUERY_PACKET_HEADER;
- packet.len = sizeof(struct hvsi_query);
- packet.seqno = atomic_inc_return(&hp->seqno);
- packet.verb = verb;
-
- pr_debug("%s: sending %i bytes\n", __func__, packet.len);
- dbg_dump_hex((uint8_t*)&packet, packet.len);
-
- wrote = hvc_put_chars(hp->vtermno, (char *)&packet, packet.len);
- if (wrote != packet.len) {
- printk(KERN_ERR "hvsi%i: couldn't send query (%i)!\n", hp->index,
- wrote);
- return -EIO;
- }
-
- return 0;
-}
-
-static int hvsi_get_mctrl(struct hvsi_struct *hp)
-{
- int ret;
-
- set_state(hp, HVSI_WAIT_FOR_MCTRL_RESPONSE);
- hvsi_query(hp, VSV_SEND_MODEM_CTL_STATUS);
-
- ret = hvsi_wait(hp, HVSI_OPEN);
- if (ret < 0) {
- printk(KERN_ERR "hvsi%i: didn't get modem flags\n", hp->index);
- set_state(hp, HVSI_OPEN);
- return ret;
- }
-
- pr_debug("%s: mctrl 0x%x\n", __func__, hp->mctrl);
-
- return 0;
-}
-
-/* note that we can only set DTR */
-static int hvsi_set_mctrl(struct hvsi_struct *hp, uint16_t mctrl)
-{
- struct hvsi_control packet __ALIGNED__;
- int wrote;
-
- packet.type = VS_CONTROL_PACKET_HEADER,
- packet.seqno = atomic_inc_return(&hp->seqno);
- packet.len = sizeof(struct hvsi_control);
- packet.verb = VSV_SET_MODEM_CTL;
- packet.mask = HVSI_TSDTR;
-
- if (mctrl & TIOCM_DTR)
- packet.word = HVSI_TSDTR;
-
- pr_debug("%s: sending %i bytes\n", __func__, packet.len);
- dbg_dump_hex((uint8_t*)&packet, packet.len);
-
- wrote = hvc_put_chars(hp->vtermno, (char *)&packet, packet.len);
- if (wrote != packet.len) {
- printk(KERN_ERR "hvsi%i: couldn't set DTR!\n", hp->index);
- return -EIO;
- }
-
- return 0;
-}
-
-static void hvsi_drain_input(struct hvsi_struct *hp)
-{
- uint8_t buf[HVSI_MAX_READ] __ALIGNED__;
- unsigned long end_jiffies = jiffies + HVSI_TIMEOUT;
-
- while (time_before(end_jiffies, jiffies))
- if (0 == hvsi_read(hp, buf, HVSI_MAX_READ))
- break;
-}
-
-static int hvsi_handshake(struct hvsi_struct *hp)
-{
- int ret;
-
- /*
- * We could have a CLOSE or other data waiting for us before we even try
- * to open; try to throw it all away so we don't get confused. (CLOSE
- * is the first message sent up the pipe when the FSP comes online. We
- * need to distinguish between "it came up a while ago and we're the first
- * user" and "it was just reset before it saw our handshake packet".)
- */
- hvsi_drain_input(hp);
-
- set_state(hp, HVSI_WAIT_FOR_VER_RESPONSE);
- ret = hvsi_query(hp, VSV_SEND_VERSION_NUMBER);
- if (ret < 0) {
- printk(KERN_ERR "hvsi%i: couldn't send version query\n", hp->index);
- return ret;
- }
-
- ret = hvsi_wait(hp, HVSI_OPEN);
- if (ret < 0)
- return ret;
-
- return 0;
-}
-
-static void hvsi_handshaker(struct work_struct *work)
-{
- struct hvsi_struct *hp =
- container_of(work, struct hvsi_struct, handshaker);
-
- if (hvsi_handshake(hp) >= 0)
- return;
-
- printk(KERN_ERR "hvsi%i: re-handshaking failed\n", hp->index);
- if (is_console(hp)) {
- /*
- * ttys will re-attempt the handshake via hvsi_open, but
- * the console will not.
- */
- printk(KERN_ERR "hvsi%i: lost console!\n", hp->index);
- }
-}
-
-static int hvsi_put_chars(struct hvsi_struct *hp, const char *buf, int count)
-{
- struct hvsi_data packet __ALIGNED__;
- int ret;
-
- BUG_ON(count > HVSI_MAX_OUTGOING_DATA);
-
- packet.type = VS_DATA_PACKET_HEADER;
- packet.seqno = atomic_inc_return(&hp->seqno);
- packet.len = count + sizeof(struct hvsi_header);
- memcpy(&packet.data, buf, count);
-
- ret = hvc_put_chars(hp->vtermno, (char *)&packet, packet.len);
- if (ret == packet.len) {
- /* return the number of chars written, not the packet length */
- return count;
- }
- return ret; /* return any errors */
-}
-
-static void hvsi_close_protocol(struct hvsi_struct *hp)
-{
- struct hvsi_control packet __ALIGNED__;
-
- packet.type = VS_CONTROL_PACKET_HEADER;
- packet.seqno = atomic_inc_return(&hp->seqno);
- packet.len = 6;
- packet.verb = VSV_CLOSE_PROTOCOL;
-
- pr_debug("%s: sending %i bytes\n", __func__, packet.len);
- dbg_dump_hex((uint8_t*)&packet, packet.len);
-
- hvc_put_chars(hp->vtermno, (char *)&packet, packet.len);
-}
-
-static int hvsi_open(struct tty_struct *tty, struct file *filp)
-{
- struct hvsi_struct *hp;
- unsigned long flags;
- int line = tty->index;
- int ret;
-
- pr_debug("%s\n", __func__);
-
- if (line < 0 || line >= hvsi_count)
- return -ENODEV;
- hp = &hvsi_ports[line];
-
- tty->driver_data = hp;
-
- mb();
- if (hp->state == HVSI_FSP_DIED)
- return -EIO;
-
- spin_lock_irqsave(&hp->lock, flags);
- hp->tty = tty;
- hp->count++;
- atomic_set(&hp->seqno, 0);
- h_vio_signal(hp->vtermno, VIO_IRQ_ENABLE);
- spin_unlock_irqrestore(&hp->lock, flags);
-
- if (is_console(hp))
- return 0; /* this has already been handshaked as the console */
-
- ret = hvsi_handshake(hp);
- if (ret < 0) {
- printk(KERN_ERR "%s: HVSI handshaking failed\n", tty->name);
- return ret;
- }
-
- ret = hvsi_get_mctrl(hp);
- if (ret < 0) {
- printk(KERN_ERR "%s: couldn't get initial modem flags\n", tty->name);
- return ret;
- }
-
- ret = hvsi_set_mctrl(hp, hp->mctrl | TIOCM_DTR);
- if (ret < 0) {
- printk(KERN_ERR "%s: couldn't set DTR\n", tty->name);
- return ret;
- }
-
- return 0;
-}
-
-/* wait for hvsi_write_worker to empty hp->outbuf */
-static void hvsi_flush_output(struct hvsi_struct *hp)
-{
- wait_event_timeout(hp->emptyq, (hp->n_outbuf <= 0), HVSI_TIMEOUT);
-
- /* 'writer' could still be pending if it didn't see n_outbuf = 0 yet */
- cancel_delayed_work_sync(&hp->writer);
- flush_work_sync(&hp->handshaker);
-
- /*
- * it's also possible that our timeout expired and hvsi_write_worker
- * didn't manage to push outbuf. poof.
- */
- hp->n_outbuf = 0;
-}
-
-static void hvsi_close(struct tty_struct *tty, struct file *filp)
-{
- struct hvsi_struct *hp = tty->driver_data;
- unsigned long flags;
-
- pr_debug("%s\n", __func__);
-
- if (tty_hung_up_p(filp))
- return;
-
- spin_lock_irqsave(&hp->lock, flags);
-
- if (--hp->count == 0) {
- hp->tty = NULL;
- hp->inbuf_end = hp->inbuf; /* discard remaining partial packets */
-
- /* only close down connection if it is not the console */
- if (!is_console(hp)) {
- h_vio_signal(hp->vtermno, VIO_IRQ_DISABLE); /* no more irqs */
- __set_state(hp, HVSI_CLOSED);
- /*
- * any data delivered to the tty layer after this will be
- * discarded (except for XON/XOFF)
- */
- tty->closing = 1;
-
- spin_unlock_irqrestore(&hp->lock, flags);
-
- /* let any existing irq handlers finish. no more will start. */
- synchronize_irq(hp->virq);
-
- /* hvsi_write_worker will re-schedule until outbuf is empty. */
- hvsi_flush_output(hp);
-
- /* tell FSP to stop sending data */
- hvsi_close_protocol(hp);
-
- /*
- * drain anything FSP is still in the middle of sending, and let
- * hvsi_handshake drain the rest on the next open.
- */
- hvsi_drain_input(hp);
-
- spin_lock_irqsave(&hp->lock, flags);
- }
- } else if (hp->count < 0)
- printk(KERN_ERR "hvsi_close %lu: oops, count is %d\n",
- hp - hvsi_ports, hp->count);
-
- spin_unlock_irqrestore(&hp->lock, flags);
-}
-
-static void hvsi_hangup(struct tty_struct *tty)
-{
- struct hvsi_struct *hp = tty->driver_data;
- unsigned long flags;
-
- pr_debug("%s\n", __func__);
-
- spin_lock_irqsave(&hp->lock, flags);
-
- hp->count = 0;
- hp->n_outbuf = 0;
- hp->tty = NULL;
-
- spin_unlock_irqrestore(&hp->lock, flags);
-}
-
-/* called with hp->lock held */
-static void hvsi_push(struct hvsi_struct *hp)
-{
- int n;
-
- if (hp->n_outbuf <= 0)
- return;
-
- n = hvsi_put_chars(hp, hp->outbuf, hp->n_outbuf);
- if (n > 0) {
- /* success */
- pr_debug("%s: wrote %i chars\n", __func__, n);
- hp->n_outbuf = 0;
- } else if (n == -EIO) {
- __set_state(hp, HVSI_FSP_DIED);
- printk(KERN_ERR "hvsi%i: service processor died\n", hp->index);
- }
-}
-
-/* hvsi_write_worker will keep rescheduling itself until outbuf is empty */
-static void hvsi_write_worker(struct work_struct *work)
-{
- struct hvsi_struct *hp =
- container_of(work, struct hvsi_struct, writer.work);
- unsigned long flags;
-#ifdef DEBUG
- static long start_j = 0;
-
- if (start_j == 0)
- start_j = jiffies;
-#endif /* DEBUG */
-
- spin_lock_irqsave(&hp->lock, flags);
-
- pr_debug("%s: %i chars in buffer\n", __func__, hp->n_outbuf);
-
- if (!is_open(hp)) {
- /*
- * We could have a non-open connection if the service processor died
- * while we were busily scheduling ourselves. In that case, it could
- * be minutes before the service processor comes back, so only try
- * again once a second.
- */
- schedule_delayed_work(&hp->writer, HZ);
- goto out;
- }
-
- hvsi_push(hp);
- if (hp->n_outbuf > 0)
- schedule_delayed_work(&hp->writer, 10);
- else {
-#ifdef DEBUG
- pr_debug("%s: outbuf emptied after %li jiffies\n", __func__,
- jiffies - start_j);
- start_j = 0;
-#endif /* DEBUG */
- wake_up_all(&hp->emptyq);
- tty_wakeup(hp->tty);
- }
-
-out:
- spin_unlock_irqrestore(&hp->lock, flags);
-}
-
-static int hvsi_write_room(struct tty_struct *tty)
-{
- struct hvsi_struct *hp = tty->driver_data;
-
- return N_OUTBUF - hp->n_outbuf;
-}
-
-static int hvsi_chars_in_buffer(struct tty_struct *tty)
-{
- struct hvsi_struct *hp = tty->driver_data;
-
- return hp->n_outbuf;
-}
-
-static int hvsi_write(struct tty_struct *tty,
- const unsigned char *buf, int count)
-{
- struct hvsi_struct *hp = tty->driver_data;
- const char *source = buf;
- unsigned long flags;
- int total = 0;
- int origcount = count;
-
- spin_lock_irqsave(&hp->lock, flags);
-
- pr_debug("%s: %i chars in buffer\n", __func__, hp->n_outbuf);
-
- if (!is_open(hp)) {
- /* we're either closing or not yet open; don't accept data */
- pr_debug("%s: not open\n", __func__);
- goto out;
- }
-
- /*
- * when the hypervisor buffer (16K) fills, data will stay in hp->outbuf
- * and hvsi_write_worker will be scheduled. subsequent hvsi_write() calls
- * will see there is no room in outbuf and return.
- */
- while ((count > 0) && (hvsi_write_room(hp->tty) > 0)) {
- int chunksize = min(count, hvsi_write_room(hp->tty));
-
- BUG_ON(hp->n_outbuf < 0);
- memcpy(hp->outbuf + hp->n_outbuf, source, chunksize);
- hp->n_outbuf += chunksize;
-
- total += chunksize;
- source += chunksize;
- count -= chunksize;
- hvsi_push(hp);
- }
-
- if (hp->n_outbuf > 0) {
- /*
- * we weren't able to write it all to the hypervisor.
- * schedule another push attempt.
- */
- schedule_delayed_work(&hp->writer, 10);
- }
-
-out:
- spin_unlock_irqrestore(&hp->lock, flags);
-
- if (total != origcount)
- pr_debug("%s: wanted %i, only wrote %i\n", __func__, origcount,
- total);
-
- return total;
-}
-
-/*
- * I have never seen throttle or unthrottle called, so this little throttle
- * buffering scheme may or may not work.
- */
-static void hvsi_throttle(struct tty_struct *tty)
-{
- struct hvsi_struct *hp = tty->driver_data;
-
- pr_debug("%s\n", __func__);
-
- h_vio_signal(hp->vtermno, VIO_IRQ_DISABLE);
-}
-
-static void hvsi_unthrottle(struct tty_struct *tty)
-{
- struct hvsi_struct *hp = tty->driver_data;
- unsigned long flags;
- int shouldflip = 0;
-
- pr_debug("%s\n", __func__);
-
- spin_lock_irqsave(&hp->lock, flags);
- if (hp->n_throttle) {
- hvsi_send_overflow(hp);
- shouldflip = 1;
- }
- spin_unlock_irqrestore(&hp->lock, flags);
-
- if (shouldflip)
- tty_flip_buffer_push(hp->tty);
-
- h_vio_signal(hp->vtermno, VIO_IRQ_ENABLE);
-}
-
-static int hvsi_tiocmget(struct tty_struct *tty, struct file *file)
-{
- struct hvsi_struct *hp = tty->driver_data;
-
- hvsi_get_mctrl(hp);
- return hp->mctrl;
-}
-
-static int hvsi_tiocmset(struct tty_struct *tty, struct file *file,
- unsigned int set, unsigned int clear)
-{
- struct hvsi_struct *hp = tty->driver_data;
- unsigned long flags;
- uint16_t new_mctrl;
-
- /* we can only alter DTR */
- clear &= TIOCM_DTR;
- set &= TIOCM_DTR;
-
- spin_lock_irqsave(&hp->lock, flags);
-
- new_mctrl = (hp->mctrl & ~clear) | set;
-
- if (hp->mctrl != new_mctrl) {
- hvsi_set_mctrl(hp, new_mctrl);
- hp->mctrl = new_mctrl;
- }
- spin_unlock_irqrestore(&hp->lock, flags);
-
- return 0;
-}
-
-
-static const struct tty_operations hvsi_ops = {
- .open = hvsi_open,
- .close = hvsi_close,
- .write = hvsi_write,
- .hangup = hvsi_hangup,
- .write_room = hvsi_write_room,
- .chars_in_buffer = hvsi_chars_in_buffer,
- .throttle = hvsi_throttle,
- .unthrottle = hvsi_unthrottle,
- .tiocmget = hvsi_tiocmget,
- .tiocmset = hvsi_tiocmset,
-};
-
-static int __init hvsi_init(void)
-{
- int i;
-
- hvsi_driver = alloc_tty_driver(hvsi_count);
- if (!hvsi_driver)
- return -ENOMEM;
-
- hvsi_driver->owner = THIS_MODULE;
- hvsi_driver->driver_name = "hvsi";
- hvsi_driver->name = "hvsi";
- hvsi_driver->major = HVSI_MAJOR;
- hvsi_driver->minor_start = HVSI_MINOR;
- hvsi_driver->type = TTY_DRIVER_TYPE_SYSTEM;
- hvsi_driver->init_termios = tty_std_termios;
- hvsi_driver->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL;
- hvsi_driver->init_termios.c_ispeed = 9600;
- hvsi_driver->init_termios.c_ospeed = 9600;
- hvsi_driver->flags = TTY_DRIVER_REAL_RAW;
- tty_set_operations(hvsi_driver, &hvsi_ops);
-
- for (i=0; i < hvsi_count; i++) {
- struct hvsi_struct *hp = &hvsi_ports[i];
- int ret = 1;
-
- ret = request_irq(hp->virq, hvsi_interrupt, IRQF_DISABLED, "hvsi", hp);
- if (ret)
- printk(KERN_ERR "HVSI: couldn't reserve irq 0x%x (error %i)\n",
- hp->virq, ret);
- }
- hvsi_wait = wait_for_state; /* irqs active now */
-
- if (tty_register_driver(hvsi_driver))
- panic("Couldn't register hvsi console driver\n");
-
- printk(KERN_DEBUG "HVSI: registered %i devices\n", hvsi_count);
-
- return 0;
-}
-device_initcall(hvsi_init);
-
-/***** console (not tty) code: *****/
-
-static void hvsi_console_print(struct console *console, const char *buf,
- unsigned int count)
-{
- struct hvsi_struct *hp = &hvsi_ports[console->index];
- char c[HVSI_MAX_OUTGOING_DATA] __ALIGNED__;
- unsigned int i = 0, n = 0;
- int ret, donecr = 0;
-
- mb();
- if (!is_open(hp))
- return;
-
- /*
- * ugh, we have to translate LF -> CRLF ourselves, in place.
- * copied from hvc_console.c:
- */
- while (count > 0 || i > 0) {
- if (count > 0 && i < sizeof(c)) {
- if (buf[n] == '\n' && !donecr) {
- c[i++] = '\r';
- donecr = 1;
- } else {
- c[i++] = buf[n++];
- donecr = 0;
- --count;
- }
- } else {
- ret = hvsi_put_chars(hp, c, i);
- if (ret < 0)
- i = 0;
- i -= ret;
- }
- }
-}
-
-static struct tty_driver *hvsi_console_device(struct console *console,
- int *index)
-{
- *index = console->index;
- return hvsi_driver;
-}
-
-static int __init hvsi_console_setup(struct console *console, char *options)
-{
- struct hvsi_struct *hp;
- int ret;
-
- if (console->index < 0 || console->index >= hvsi_count)
- return -1;
- hp = &hvsi_ports[console->index];
-
- /* give the FSP a chance to change the baud rate when we re-open */
- hvsi_close_protocol(hp);
-
- ret = hvsi_handshake(hp);
- if (ret < 0)
- return ret;
-
- ret = hvsi_get_mctrl(hp);
- if (ret < 0)
- return ret;
-
- ret = hvsi_set_mctrl(hp, hp->mctrl | TIOCM_DTR);
- if (ret < 0)
- return ret;
-
- hp->flags |= HVSI_CONSOLE;
-
- return 0;
-}
-
-static struct console hvsi_console = {
- .name = "hvsi",
- .write = hvsi_console_print,
- .device = hvsi_console_device,
- .setup = hvsi_console_setup,
- .flags = CON_PRINTBUFFER,
- .index = -1,
-};
-
-static int __init hvsi_console_init(void)
-{
- struct device_node *vty;
-
- hvsi_wait = poll_for_state; /* no irqs yet; must poll */
-
- /* search device tree for vty nodes */
- for (vty = of_find_compatible_node(NULL, "serial", "hvterm-protocol");
- vty != NULL;
- vty = of_find_compatible_node(vty, "serial", "hvterm-protocol")) {
- struct hvsi_struct *hp;
- const uint32_t *vtermno, *irq;
-
- vtermno = of_get_property(vty, "reg", NULL);
- irq = of_get_property(vty, "interrupts", NULL);
- if (!vtermno || !irq)
- continue;
-
- if (hvsi_count >= MAX_NR_HVSI_CONSOLES) {
- of_node_put(vty);
- break;
- }
-
- hp = &hvsi_ports[hvsi_count];
- INIT_DELAYED_WORK(&hp->writer, hvsi_write_worker);
- INIT_WORK(&hp->handshaker, hvsi_handshaker);
- init_waitqueue_head(&hp->emptyq);
- init_waitqueue_head(&hp->stateq);
- spin_lock_init(&hp->lock);
- hp->index = hvsi_count;
- hp->inbuf_end = hp->inbuf;
- hp->state = HVSI_CLOSED;
- hp->vtermno = *vtermno;
- hp->virq = irq_create_mapping(NULL, irq[0]);
- if (hp->virq == NO_IRQ) {
- printk(KERN_ERR "%s: couldn't create irq mapping for 0x%x\n",
- __func__, irq[0]);
- continue;
- }
-
- hvsi_count++;
- }
-
- if (hvsi_count)
- register_console(&hvsi_console);
- return 0;
-}
-console_initcall(hvsi_console_init);
projects / mv-sheeva.git / blobdiff