https://github.com/torvalds/linux
Tip revision: 58720809f52779dc0f08e53e54b014209d13eebb authored by Linus Torvalds on 15 October 2023, 20:34:39 UTC
Linux 6.6-rc6
Linux 6.6-rc6
Tip revision: 5872080
saa7164-cmd.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Driver for the NXP SAA7164 PCIe bridge
*
* Copyright (c) 2010-2015 Steven Toth <stoth@kernellabs.com>
*/
#include <linux/wait.h>
#include "saa7164.h"
static 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;
}
static 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);
}
static 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);
}
static 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, i = 0;
u32 timeout;
wait_queue_head_t *q = NULL;
u8 tmp[512];
dprintk(DBGLVL_CMD, "%s()\n", __func__);
/* While any outstand message on the bus exists... */
do {
/* Peek the msg bus */
struct tmComResInfo 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__);
/* Clean the bus */
ret = saa7164_bus_get(dev, &tRsp, &tmp, 0);
printk(KERN_ERR "%s() ret = %x\n", __func__, ret);
if (ret == SAA_ERR_EMPTY)
/* Someone else already fetched the response */
return SAA_OK;
if (ret != SAA_OK)
return ret;
}
/* It's unlikely to have more than 4 or 5 pending messages,
* ensure we exit at some point regardless.
*/
} while (i++ < 32);
return ret;
}
/* Commands to the f/w get marshelled to/from this code then onto the PCI
* -bus/c running buffer. */
static int saa7164_cmd_dequeue(struct saa7164_dev *dev)
{
int ret;
u32 timeout;
wait_queue_head_t *q = NULL;
u8 tmp[512];
dprintk(DBGLVL_CMD, "%s()\n", __func__);
while (true) {
struct tmComResInfo 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;
}
}
static int saa7164_cmd_set(struct saa7164_dev *dev, struct tmComResInfo *msg,
void *buf)
{
struct tmComResBusInfo *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;
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 occurred, or SAA_OK if it was signaled during the wait.
*/
static int saa7164_cmd_wait(struct saa7164_dev *dev, u8 seqno)
{
wait_queue_head_t *q = NULL;
int ret = SAA_BUS_TIMEOUT;
unsigned long stamp;
int r;
if (saa_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, enum tmComResCmd command,
u16 controlselector, u16 size, void *buf)
{
struct tmComResInfo command_t, *pcommand_t;
struct tmComResInfo 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 == NULL)) {
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__);
ret = SAA_ERR_NOT_SUPPORTED;
break;
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, NULL, 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");
} /* (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;
}