linux-kernel-test/drivers/media/video/saa7164/saa7164-cmd.c
Steven Toth 39e469ab6d V4L/DVB (12940): SAA7164: IRQ / message timeout related change
In some cases we're seeing large timeouts on commands. I'm changing the
implementation so that the deferred worker checks the PCI bus for
any messages and signals the waiting caller accordingly. The previous
mechanism was too unreliable.

Signed-off-by: Steven Toth <stoth@kernellabs.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2009-09-19 00:15:08 -03:00

573 lines
14 KiB
C

/*
* Driver for the NXP SAA7164 PCIe bridge
*
* Copyright (c) 2009 Steven Toth <stoth@kernellabs.com>
*
* 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/wait.h>
#include "saa7164.h"
int saa7164_cmd_alloc_seqno(struct saa7164_dev *dev)
{
int i, ret = -1;
mutex_lock(&dev->lock);
for (i = 0; i < SAA_CMD_MAX_MSG_UNITS; i++) {
if (dev->cmds[i].inuse == 0) {
dev->cmds[i].inuse = 1;
dev->cmds[i].signalled = 0;
dev->cmds[i].timeout = 0;
ret = dev->cmds[i].seqno;
break;
}
}
mutex_unlock(&dev->lock);
return ret;
}
void saa7164_cmd_free_seqno(struct saa7164_dev *dev, u8 seqno)
{
mutex_lock(&dev->lock);
if ((dev->cmds[seqno].inuse == 1) &&
(dev->cmds[seqno].seqno == seqno)) {
dev->cmds[seqno].inuse = 0;
dev->cmds[seqno].signalled = 0;
dev->cmds[seqno].timeout = 0;
}
mutex_unlock(&dev->lock);
}
void saa7164_cmd_timeout_seqno(struct saa7164_dev *dev, u8 seqno)
{
mutex_lock(&dev->lock);
if ((dev->cmds[seqno].inuse == 1) &&
(dev->cmds[seqno].seqno == seqno)) {
dev->cmds[seqno].timeout = 1;
}
mutex_unlock(&dev->lock);
}
u32 saa7164_cmd_timeout_get(struct saa7164_dev *dev, u8 seqno)
{
int ret = 0;
mutex_lock(&dev->lock);
if ((dev->cmds[seqno].inuse == 1) &&
(dev->cmds[seqno].seqno == seqno)) {
ret = dev->cmds[seqno].timeout;
}
mutex_unlock(&dev->lock);
return ret;
}
/* Commands to the f/w get marshelled to/from this code then onto the PCI
* -bus/c running buffer. */
int saa7164_irq_dequeue(struct saa7164_dev *dev)
{
int ret = SAA_OK;
u32 timeout;
wait_queue_head_t *q = 0;
dprintk(DBGLVL_CMD, "%s()\n", __func__);
/* While any outstand message on the bus exists... */
do {
/* Peek the msg bus */
tmComResInfo_t tRsp = { 0, 0, 0, 0, 0, 0 };
ret = saa7164_bus_get(dev, &tRsp, NULL, 1);
if (ret != SAA_OK)
break;
q = &dev->cmds[tRsp.seqno].wait;
timeout = saa7164_cmd_timeout_get(dev, tRsp.seqno);
dprintk(DBGLVL_CMD, "%s() timeout = %d\n", __func__, timeout);
if (!timeout) {
dprintk(DBGLVL_CMD,
"%s() signalled seqno(%d) (for dequeue)\n",
__func__, tRsp.seqno);
dev->cmds[tRsp.seqno].signalled = 1;
wake_up(q);
} else {
printk(KERN_ERR
"%s() found timed out command on the bus\n",
__func__);
}
} while (0);
return ret;
}
/* Commands to the f/w get marshelled to/from this code then onto the PCI
* -bus/c running buffer. */
int saa7164_cmd_dequeue(struct saa7164_dev *dev)
{
int loop = 1;
int ret;
u32 timeout;
wait_queue_head_t *q = 0;
u8 tmp[512];
dprintk(DBGLVL_CMD, "%s()\n", __func__);
while (loop) {
tmComResInfo_t tRsp = { 0, 0, 0, 0, 0, 0 };
ret = saa7164_bus_get(dev, &tRsp, NULL, 1);
if (ret == SAA_ERR_EMPTY)
return SAA_OK;
if (ret != SAA_OK)
return ret;
q = &dev->cmds[tRsp.seqno].wait;
timeout = saa7164_cmd_timeout_get(dev, tRsp.seqno);
dprintk(DBGLVL_CMD, "%s() timeout = %d\n", __func__, timeout);
if (timeout) {
printk(KERN_ERR "found timed out command on the bus\n");
/* Clean the bus */
ret = saa7164_bus_get(dev, &tRsp, &tmp, 0);
printk(KERN_ERR "ret = %x\n", ret);
if (ret == SAA_ERR_EMPTY)
/* Someone else already fetched the response */
return SAA_OK;
if (ret != SAA_OK)
return ret;
if (tRsp.flags & PVC_CMDFLAG_CONTINUE)
printk(KERN_ERR "split response\n");
else
saa7164_cmd_free_seqno(dev, tRsp.seqno);
printk(KERN_ERR " timeout continue\n");
continue;
}
dprintk(DBGLVL_CMD, "%s() signalled seqno(%d) (for dequeue)\n",
__func__, tRsp.seqno);
dev->cmds[tRsp.seqno].signalled = 1;
wake_up(q);
return SAA_OK;
}
return SAA_OK;
}
int saa7164_cmd_set(struct saa7164_dev *dev, tmComResInfo_t* msg, void *buf)
{
tmComResBusInfo_t *bus = &dev->bus;
u8 cmd_sent;
u16 size, idx;
u32 cmds;
void *tmp;
int ret = -1;
if (!msg) {
printk(KERN_ERR "%s() !msg\n", __func__);
return SAA_ERR_BAD_PARAMETER;
}
mutex_lock(&dev->cmds[msg->id].lock);
size = msg->size;
idx = 0;
cmds = size / bus->m_wMaxReqSize;
if (size % bus->m_wMaxReqSize == 0)
cmds -= 1;
cmd_sent = 0;
/* Split the request into smaller chunks */
for (idx = 0; idx < cmds; idx++) {
msg->flags |= SAA_CMDFLAG_CONTINUE;
msg->size = bus->m_wMaxReqSize;
tmp = buf + idx * bus->m_wMaxReqSize;
ret = saa7164_bus_set(dev, msg, tmp);
if (ret != SAA_OK) {
printk(KERN_ERR "%s() set failed %d\n", __func__, ret);
if (cmd_sent) {
ret = SAA_ERR_BUSY;
goto out;
}
ret = SAA_ERR_OVERFLOW;
goto out;
}
cmd_sent = 1;
}
/* If not the last command... */
if (idx != 0)
msg->flags &= ~SAA_CMDFLAG_CONTINUE;
msg->size = size - idx * bus->m_wMaxReqSize;
ret = saa7164_bus_set(dev, msg, buf + idx * bus->m_wMaxReqSize);
if (ret != SAA_OK) {
printk(KERN_ERR "%s() set last failed %d\n", __func__, ret);
if (cmd_sent) {
ret = SAA_ERR_BUSY;
goto out;
}
ret = SAA_ERR_OVERFLOW;
goto out;
}
ret = SAA_OK;
out:
mutex_unlock(&dev->cmds[msg->id].lock);
return ret;
}
/* Wait for a signal event, without holding a mutex. Either return TIMEOUT if
* the event never occured, or SAA_OK if it was signaled during the wait.
*/
int saa7164_cmd_wait(struct saa7164_dev *dev, u8 seqno)
{
wait_queue_head_t *q = 0;
int ret = SAA_BUS_TIMEOUT;
unsigned long stamp;
int r;
if (debug >= 4)
saa7164_bus_dump(dev);
dprintk(DBGLVL_CMD, "%s(seqno=%d)\n", __func__, seqno);
mutex_lock(&dev->lock);
if ((dev->cmds[seqno].inuse == 1) &&
(dev->cmds[seqno].seqno == seqno)) {
q = &dev->cmds[seqno].wait;
}
mutex_unlock(&dev->lock);
if (q) {
/* If we haven't been signalled we need to wait */
if (dev->cmds[seqno].signalled == 0) {
stamp = jiffies;
dprintk(DBGLVL_CMD,
"%s(seqno=%d) Waiting (signalled=%d)\n",
__func__, seqno, dev->cmds[seqno].signalled);
/* Wait for signalled to be flagged or timeout */
/* In a highly stressed system this can easily extend
* into multiple seconds before the deferred worker
* is scheduled, and we're woken up via signal.
* We typically are signalled in < 50ms but it can
* take MUCH longer.
*/
wait_event_timeout(*q, dev->cmds[seqno].signalled, (HZ * waitsecs));
r = time_before(jiffies, stamp + (HZ * waitsecs));
if (r)
ret = SAA_OK;
else
saa7164_cmd_timeout_seqno(dev, seqno);
dprintk(DBGLVL_CMD, "%s(seqno=%d) Waiting res = %d "
"(signalled=%d)\n", __func__, seqno, r,
dev->cmds[seqno].signalled);
} else
ret = SAA_OK;
} else
printk(KERN_ERR "%s(seqno=%d) seqno is invalid\n",
__func__, seqno);
return ret;
}
void saa7164_cmd_signal(struct saa7164_dev *dev, u8 seqno)
{
int i;
dprintk(DBGLVL_CMD, "%s()\n", __func__);
mutex_lock(&dev->lock);
for (i = 0; i < SAA_CMD_MAX_MSG_UNITS; i++) {
if (dev->cmds[i].inuse == 1) {
dprintk(DBGLVL_CMD,
"seqno %d inuse, sig = %d, t/out = %d\n",
dev->cmds[i].seqno,
dev->cmds[i].signalled,
dev->cmds[i].timeout);
}
}
for (i = 0; i < SAA_CMD_MAX_MSG_UNITS; i++) {
if ((dev->cmds[i].inuse == 1) && ((i == 0) ||
(dev->cmds[i].signalled) || (dev->cmds[i].timeout))) {
dprintk(DBGLVL_CMD, "%s(seqno=%d) calling wake_up\n",
__func__, i);
dev->cmds[i].signalled = 1;
wake_up(&dev->cmds[i].wait);
}
}
mutex_unlock(&dev->lock);
}
int saa7164_cmd_send(struct saa7164_dev *dev, u8 id, tmComResCmd_t command,
u16 controlselector, u16 size, void *buf)
{
tmComResInfo_t command_t, *pcommand_t;
tmComResInfo_t response_t, *presponse_t;
u8 errdata[256];
u16 resp_dsize;
u16 data_recd;
u32 loop;
int ret;
int safety = 0;
dprintk(DBGLVL_CMD, "%s(unitid = %s (%d) , command = 0x%x, "
"sel = 0x%x)\n", __func__, saa7164_unitid_name(dev, id), id,
command, controlselector);
if ((size == 0) || (buf == 0)) {
printk(KERN_ERR "%s() Invalid param\n", __func__);
return SAA_ERR_BAD_PARAMETER;
}
/* Prepare some basic command/response structures */
memset(&command_t, 0, sizeof(command_t));
memset(&response_t, 0, sizeof(&response_t));
pcommand_t = &command_t;
presponse_t = &response_t;
command_t.id = id;
command_t.command = command;
command_t.controlselector = controlselector;
command_t.size = size;
/* Allocate a unique sequence number */
ret = saa7164_cmd_alloc_seqno(dev);
if (ret < 0) {
printk(KERN_ERR "%s() No free sequences\n", __func__);
ret = SAA_ERR_NO_RESOURCES;
goto out;
}
command_t.seqno = (u8)ret;
/* Send Command */
resp_dsize = size;
pcommand_t->size = size;
dprintk(DBGLVL_CMD, "%s() pcommand_t.seqno = %d\n",
__func__, pcommand_t->seqno);
dprintk(DBGLVL_CMD, "%s() pcommand_t.size = %d\n",
__func__, pcommand_t->size);
ret = saa7164_cmd_set(dev, pcommand_t, buf);
if (ret != SAA_OK) {
printk(KERN_ERR "%s() set command failed %d\n", __func__, ret);
if (ret != SAA_ERR_BUSY)
saa7164_cmd_free_seqno(dev, pcommand_t->seqno);
else
/* Flag a timeout, because at least one
* command was sent */
saa7164_cmd_timeout_seqno(dev, pcommand_t->seqno);
goto out;
}
/* With split responses we have to collect the msgs piece by piece */
data_recd = 0;
loop = 1;
while (loop) {
dprintk(DBGLVL_CMD, "%s() loop\n", __func__);
ret = saa7164_cmd_wait(dev, pcommand_t->seqno);
dprintk(DBGLVL_CMD, "%s() loop ret = %d\n", __func__, ret);
/* if power is down and this is not a power command ... */
if (ret == SAA_BUS_TIMEOUT) {
printk(KERN_ERR "Event timed out\n");
saa7164_cmd_timeout_seqno(dev, pcommand_t->seqno);
return ret;
}
if (ret != SAA_OK) {
printk(KERN_ERR "spurious error\n");
return ret;
}
/* Peek response */
ret = saa7164_bus_get(dev, presponse_t, NULL, 1);
if (ret == SAA_ERR_EMPTY) {
dprintk(4, "%s() SAA_ERR_EMPTY\n", __func__);
continue;
}
if (ret != SAA_OK) {
printk(KERN_ERR "peek failed\n");
return ret;
}
dprintk(DBGLVL_CMD, "%s() presponse_t->seqno = %d\n",
__func__, presponse_t->seqno);
dprintk(DBGLVL_CMD, "%s() presponse_t->flags = 0x%x\n",
__func__, presponse_t->flags);
dprintk(DBGLVL_CMD, "%s() presponse_t->size = %d\n",
__func__, presponse_t->size);
/* Check if the response was for our command */
if (presponse_t->seqno != pcommand_t->seqno) {
dprintk(DBGLVL_CMD,
"wrong event: seqno = %d, "
"expected seqno = %d, "
"will dequeue regardless\n",
presponse_t->seqno, pcommand_t->seqno);
ret = saa7164_cmd_dequeue(dev);
if (ret != SAA_OK) {
printk(KERN_ERR "dequeue failed, ret = %d\n",
ret);
if (safety++ > 16) {
printk(KERN_ERR
"dequeue exceeded, safety exit\n");
return SAA_ERR_BUSY;
}
}
continue;
}
if ((presponse_t->flags & PVC_RESPONSEFLAG_ERROR) != 0) {
memset(&errdata[0], 0, sizeof(errdata));
ret = saa7164_bus_get(dev, presponse_t, &errdata[0], 0);
if (ret != SAA_OK) {
printk(KERN_ERR "get error(2)\n");
return ret;
}
saa7164_cmd_free_seqno(dev, pcommand_t->seqno);
dprintk(DBGLVL_CMD, "%s() errdata %02x%02x%02x%02x\n",
__func__, errdata[0], errdata[1], errdata[2],
errdata[3]);
/* Map error codes */
dprintk(DBGLVL_CMD, "%s() cmd, error code = 0x%x\n",
__func__, errdata[0]);
switch (errdata[0]) {
case PVC_ERRORCODE_INVALID_COMMAND:
dprintk(DBGLVL_CMD, "%s() INVALID_COMMAND\n",
__func__);
ret = SAA_ERR_INVALID_COMMAND;
break;
case PVC_ERRORCODE_INVALID_DATA:
dprintk(DBGLVL_CMD, "%s() INVALID_DATA\n",
__func__);
ret = SAA_ERR_BAD_PARAMETER;
break;
case PVC_ERRORCODE_TIMEOUT:
dprintk(DBGLVL_CMD, "%s() TIMEOUT\n", __func__);
ret = SAA_ERR_TIMEOUT;
break;
case PVC_ERRORCODE_NAK:
dprintk(DBGLVL_CMD, "%s() NAK\n", __func__);
ret = SAA_ERR_NULL_PACKET;
break;
case PVC_ERRORCODE_UNKNOWN:
case PVC_ERRORCODE_INVALID_CONTROL:
dprintk(DBGLVL_CMD,
"%s() UNKNOWN OR INVALID CONTROL\n",
__func__);
default:
dprintk(DBGLVL_CMD, "%s() UNKNOWN\n", __func__);
ret = SAA_ERR_NOT_SUPPORTED;
}
/* See of other commands are on the bus */
if (saa7164_cmd_dequeue(dev) != SAA_OK)
printk(KERN_ERR "dequeue(2) failed\n");
return ret;
}
/* If response is invalid */
if ((presponse_t->id != pcommand_t->id) ||
(presponse_t->command != pcommand_t->command) ||
(presponse_t->controlselector !=
pcommand_t->controlselector) ||
(((resp_dsize - data_recd) != presponse_t->size) &&
!(presponse_t->flags & PVC_CMDFLAG_CONTINUE)) ||
((resp_dsize - data_recd) < presponse_t->size)) {
/* Invalid */
dprintk(DBGLVL_CMD, "%s() Invalid\n", __func__);
ret = saa7164_bus_get(dev, presponse_t, 0, 0);
if (ret != SAA_OK) {
printk(KERN_ERR "get failed\n");
return ret;
}
/* See of other commands are on the bus */
if (saa7164_cmd_dequeue(dev) != SAA_OK)
printk(KERN_ERR "dequeue(3) failed\n");
continue;
}
/* OK, now we're actually getting out correct response */
ret = saa7164_bus_get(dev, presponse_t, buf + data_recd, 0);
if (ret != SAA_OK) {
printk(KERN_ERR "get failed\n");
return ret;
}
data_recd = presponse_t->size + data_recd;
if (resp_dsize == data_recd) {
dprintk(DBGLVL_CMD, "%s() Resp recd\n", __func__);
break;
}
/* See of other commands are on the bus */
if (saa7164_cmd_dequeue(dev) != SAA_OK)
printk(KERN_ERR "dequeue(3) failed\n");
continue;
} /* (loop) */
/* Release the sequence number allocation */
saa7164_cmd_free_seqno(dev, pcommand_t->seqno);
/* if powerdown signal all pending commands */
dprintk(DBGLVL_CMD, "%s() Calling dequeue then exit\n", __func__);
/* See of other commands are on the bus */
if (saa7164_cmd_dequeue(dev) != SAA_OK)
printk(KERN_ERR "dequeue(4) failed\n");
ret = SAA_OK;
out:
return ret;
}