linux/drivers/net/wireless/ath/ath6kl/bmi.c
Kalle Valo cfc301edfb ath6kl: fix busy loop in ath6kl_bmi_get_rx_lkahd()
Brent reported that ath6kl busy loops if firmware doesn't boot for some
reason (in this case he was using an older firmware which wasn't supported
by ath6kl).

Investigation revealed that this was even on purpose,
ath6kl_bmi_get_rx_lkahd() had a parameter to disable the timeout check,
which is extremely evil. I didn't find any reason why the timeout needs
to be disabled so I just removed the feature. The function already busyloops
a maximum of one second if it doesn't get an answer, even that's too long.
If something takes longer than that a more friendly approach is needed.

Reported-by: Brent Taylor <btaylor1@motorolasolutions.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
2011-09-16 18:48:34 +03:00

690 lines
17 KiB
C

/*
* Copyright (c) 2004-2011 Atheros Communications Inc.
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include "core.h"
#include "hif-ops.h"
#include "target.h"
#include "debug.h"
static int ath6kl_get_bmi_cmd_credits(struct ath6kl *ar)
{
u32 addr;
unsigned long timeout;
int ret;
ar->bmi.cmd_credits = 0;
/* Read the counter register to get the command credits */
addr = COUNT_DEC_ADDRESS + (HTC_MAILBOX_NUM_MAX + ENDPOINT1) * 4;
timeout = jiffies + msecs_to_jiffies(BMI_COMMUNICATION_TIMEOUT);
while (time_before(jiffies, timeout) && !ar->bmi.cmd_credits) {
/*
* Hit the credit counter with a 4-byte access, the first byte
* read will hit the counter and cause a decrement, while the
* remaining 3 bytes has no effect. The rationale behind this
* is to make all HIF accesses 4-byte aligned.
*/
ret = hif_read_write_sync(ar, addr,
(u8 *)&ar->bmi.cmd_credits, 4,
HIF_RD_SYNC_BYTE_INC);
if (ret) {
ath6kl_err("Unable to decrement the command credit count register: %d\n",
ret);
return ret;
}
/* The counter is only 8 bits.
* Ignore anything in the upper 3 bytes
*/
ar->bmi.cmd_credits &= 0xFF;
}
if (!ar->bmi.cmd_credits) {
ath6kl_err("bmi communication timeout\n");
return -ETIMEDOUT;
}
return 0;
}
static int ath6kl_bmi_get_rx_lkahd(struct ath6kl *ar)
{
unsigned long timeout;
u32 rx_word = 0;
int ret = 0;
timeout = jiffies + msecs_to_jiffies(BMI_COMMUNICATION_TIMEOUT);
while (time_before(jiffies, timeout) && !rx_word) {
ret = hif_read_write_sync(ar, RX_LOOKAHEAD_VALID_ADDRESS,
(u8 *)&rx_word, sizeof(rx_word),
HIF_RD_SYNC_BYTE_INC);
if (ret) {
ath6kl_err("unable to read RX_LOOKAHEAD_VALID\n");
return ret;
}
/* all we really want is one bit */
rx_word &= (1 << ENDPOINT1);
}
if (!rx_word) {
ath6kl_err("bmi_recv_buf FIFO empty\n");
return -EINVAL;
}
return ret;
}
static int ath6kl_bmi_send_buf(struct ath6kl *ar, u8 *buf, u32 len)
{
int ret;
u32 addr;
ret = ath6kl_get_bmi_cmd_credits(ar);
if (ret)
return ret;
addr = ar->mbox_info.htc_addr;
ret = hif_read_write_sync(ar, addr, buf, len,
HIF_WR_SYNC_BYTE_INC);
if (ret)
ath6kl_err("unable to send the bmi data to the device\n");
return ret;
}
static int ath6kl_bmi_recv_buf(struct ath6kl *ar, u8 *buf, u32 len)
{
int ret;
u32 addr;
/*
* During normal bootup, small reads may be required.
* Rather than issue an HIF Read and then wait as the Target
* adds successive bytes to the FIFO, we wait here until
* we know that response data is available.
*
* This allows us to cleanly timeout on an unexpected
* Target failure rather than risk problems at the HIF level.
* In particular, this avoids SDIO timeouts and possibly garbage
* data on some host controllers. And on an interconnect
* such as Compact Flash (as well as some SDIO masters) which
* does not provide any indication on data timeout, it avoids
* a potential hang or garbage response.
*
* Synchronization is more difficult for reads larger than the
* size of the MBOX FIFO (128B), because the Target is unable
* to push the 129th byte of data until AFTER the Host posts an
* HIF Read and removes some FIFO data. So for large reads the
* Host proceeds to post an HIF Read BEFORE all the data is
* actually available to read. Fortunately, large BMI reads do
* not occur in practice -- they're supported for debug/development.
*
* So Host/Target BMI synchronization is divided into these cases:
* CASE 1: length < 4
* Should not happen
*
* CASE 2: 4 <= length <= 128
* Wait for first 4 bytes to be in FIFO
* If CONSERVATIVE_BMI_READ is enabled, also wait for
* a BMI command credit, which indicates that the ENTIRE
* response is available in the the FIFO
*
* CASE 3: length > 128
* Wait for the first 4 bytes to be in FIFO
*
* For most uses, a small timeout should be sufficient and we will
* usually see a response quickly; but there may be some unusual
* (debug) cases of BMI_EXECUTE where we want an larger timeout.
* For now, we use an unbounded busy loop while waiting for
* BMI_EXECUTE.
*
* If BMI_EXECUTE ever needs to support longer-latency execution,
* especially in production, this code needs to be enhanced to sleep
* and yield. Also note that BMI_COMMUNICATION_TIMEOUT is currently
* a function of Host processor speed.
*/
if (len >= 4) { /* NB: Currently, always true */
ret = ath6kl_bmi_get_rx_lkahd(ar);
if (ret)
return ret;
}
addr = ar->mbox_info.htc_addr;
ret = hif_read_write_sync(ar, addr, buf, len,
HIF_RD_SYNC_BYTE_INC);
if (ret) {
ath6kl_err("Unable to read the bmi data from the device: %d\n",
ret);
return ret;
}
return 0;
}
int ath6kl_bmi_done(struct ath6kl *ar)
{
int ret;
u32 cid = BMI_DONE;
if (ar->bmi.done_sent) {
ath6kl_dbg(ATH6KL_DBG_BMI, "bmi done skipped\n");
return 0;
}
ar->bmi.done_sent = true;
ret = ath6kl_bmi_send_buf(ar, (u8 *)&cid, sizeof(cid));
if (ret) {
ath6kl_err("Unable to send bmi done: %d\n", ret);
return ret;
}
ath6kl_bmi_cleanup(ar);
return 0;
}
int ath6kl_bmi_get_target_info(struct ath6kl *ar,
struct ath6kl_bmi_target_info *targ_info)
{
int ret;
u32 cid = BMI_GET_TARGET_INFO;
if (ar->bmi.done_sent) {
ath6kl_err("bmi done sent already, cmd %d disallowed\n", cid);
return -EACCES;
}
ret = ath6kl_bmi_send_buf(ar, (u8 *)&cid, sizeof(cid));
if (ret) {
ath6kl_err("Unable to send get target info: %d\n", ret);
return ret;
}
ret = ath6kl_bmi_recv_buf(ar, (u8 *)&targ_info->version,
sizeof(targ_info->version));
if (ret) {
ath6kl_err("Unable to recv target info: %d\n", ret);
return ret;
}
if (le32_to_cpu(targ_info->version) == TARGET_VERSION_SENTINAL) {
/* Determine how many bytes are in the Target's targ_info */
ret = ath6kl_bmi_recv_buf(ar,
(u8 *)&targ_info->byte_count,
sizeof(targ_info->byte_count));
if (ret) {
ath6kl_err("unable to read target info byte count: %d\n",
ret);
return ret;
}
/*
* The target's targ_info doesn't match the host's targ_info.
* We need to do some backwards compatibility to make this work.
*/
if (le32_to_cpu(targ_info->byte_count) != sizeof(*targ_info)) {
WARN_ON(1);
return -EINVAL;
}
/* Read the remainder of the targ_info */
ret = ath6kl_bmi_recv_buf(ar,
((u8 *)targ_info) +
sizeof(targ_info->byte_count),
sizeof(*targ_info) -
sizeof(targ_info->byte_count));
if (ret) {
ath6kl_err("Unable to read target info (%d bytes): %d\n",
targ_info->byte_count, ret);
return ret;
}
}
ath6kl_dbg(ATH6KL_DBG_BMI, "target info (ver: 0x%x type: 0x%x)\n",
targ_info->version, targ_info->type);
return 0;
}
int ath6kl_bmi_read(struct ath6kl *ar, u32 addr, u8 *buf, u32 len)
{
u32 cid = BMI_READ_MEMORY;
int ret;
u32 offset;
u32 len_remain, rx_len;
u16 size;
if (ar->bmi.done_sent) {
ath6kl_err("bmi done sent already, cmd %d disallowed\n", cid);
return -EACCES;
}
size = BMI_DATASZ_MAX + sizeof(cid) + sizeof(addr) + sizeof(len);
if (size > MAX_BMI_CMDBUF_SZ) {
WARN_ON(1);
return -EINVAL;
}
memset(ar->bmi.cmd_buf, 0, size);
ath6kl_dbg(ATH6KL_DBG_BMI,
"bmi read memory: device: addr: 0x%x, len: %d\n",
addr, len);
len_remain = len;
while (len_remain) {
rx_len = (len_remain < BMI_DATASZ_MAX) ?
len_remain : BMI_DATASZ_MAX;
offset = 0;
memcpy(&(ar->bmi.cmd_buf[offset]), &cid, sizeof(cid));
offset += sizeof(cid);
memcpy(&(ar->bmi.cmd_buf[offset]), &addr, sizeof(addr));
offset += sizeof(addr);
memcpy(&(ar->bmi.cmd_buf[offset]), &rx_len, sizeof(rx_len));
offset += sizeof(len);
ret = ath6kl_bmi_send_buf(ar, ar->bmi.cmd_buf, offset);
if (ret) {
ath6kl_err("Unable to write to the device: %d\n",
ret);
return ret;
}
ret = ath6kl_bmi_recv_buf(ar, ar->bmi.cmd_buf, rx_len);
if (ret) {
ath6kl_err("Unable to read from the device: %d\n",
ret);
return ret;
}
memcpy(&buf[len - len_remain], ar->bmi.cmd_buf, rx_len);
len_remain -= rx_len; addr += rx_len;
}
return 0;
}
int ath6kl_bmi_write(struct ath6kl *ar, u32 addr, u8 *buf, u32 len)
{
u32 cid = BMI_WRITE_MEMORY;
int ret;
u32 offset;
u32 len_remain, tx_len;
const u32 header = sizeof(cid) + sizeof(addr) + sizeof(len);
u8 aligned_buf[BMI_DATASZ_MAX];
u8 *src;
if (ar->bmi.done_sent) {
ath6kl_err("bmi done sent already, cmd %d disallowed\n", cid);
return -EACCES;
}
if ((BMI_DATASZ_MAX + header) > MAX_BMI_CMDBUF_SZ) {
WARN_ON(1);
return -EINVAL;
}
memset(ar->bmi.cmd_buf, 0, BMI_DATASZ_MAX + header);
ath6kl_dbg(ATH6KL_DBG_BMI,
"bmi write memory: addr: 0x%x, len: %d\n", addr, len);
len_remain = len;
while (len_remain) {
src = &buf[len - len_remain];
if (len_remain < (BMI_DATASZ_MAX - header)) {
if (len_remain & 3) {
/* align it with 4 bytes */
len_remain = len_remain +
(4 - (len_remain & 3));
memcpy(aligned_buf, src, len_remain);
src = aligned_buf;
}
tx_len = len_remain;
} else {
tx_len = (BMI_DATASZ_MAX - header);
}
offset = 0;
memcpy(&(ar->bmi.cmd_buf[offset]), &cid, sizeof(cid));
offset += sizeof(cid);
memcpy(&(ar->bmi.cmd_buf[offset]), &addr, sizeof(addr));
offset += sizeof(addr);
memcpy(&(ar->bmi.cmd_buf[offset]), &tx_len, sizeof(tx_len));
offset += sizeof(tx_len);
memcpy(&(ar->bmi.cmd_buf[offset]), src, tx_len);
offset += tx_len;
ret = ath6kl_bmi_send_buf(ar, ar->bmi.cmd_buf, offset);
if (ret) {
ath6kl_err("Unable to write to the device: %d\n",
ret);
return ret;
}
len_remain -= tx_len; addr += tx_len;
}
return 0;
}
int ath6kl_bmi_execute(struct ath6kl *ar, u32 addr, u32 *param)
{
u32 cid = BMI_EXECUTE;
int ret;
u32 offset;
u16 size;
if (ar->bmi.done_sent) {
ath6kl_err("bmi done sent already, cmd %d disallowed\n", cid);
return -EACCES;
}
size = sizeof(cid) + sizeof(addr) + sizeof(param);
if (size > MAX_BMI_CMDBUF_SZ) {
WARN_ON(1);
return -EINVAL;
}
memset(ar->bmi.cmd_buf, 0, size);
ath6kl_dbg(ATH6KL_DBG_BMI, "bmi execute: addr: 0x%x, param: %d)\n",
addr, *param);
offset = 0;
memcpy(&(ar->bmi.cmd_buf[offset]), &cid, sizeof(cid));
offset += sizeof(cid);
memcpy(&(ar->bmi.cmd_buf[offset]), &addr, sizeof(addr));
offset += sizeof(addr);
memcpy(&(ar->bmi.cmd_buf[offset]), param, sizeof(*param));
offset += sizeof(*param);
ret = ath6kl_bmi_send_buf(ar, ar->bmi.cmd_buf, offset);
if (ret) {
ath6kl_err("Unable to write to the device: %d\n", ret);
return ret;
}
ret = ath6kl_bmi_recv_buf(ar, ar->bmi.cmd_buf, sizeof(*param));
if (ret) {
ath6kl_err("Unable to read from the device: %d\n", ret);
return ret;
}
memcpy(param, ar->bmi.cmd_buf, sizeof(*param));
return 0;
}
int ath6kl_bmi_set_app_start(struct ath6kl *ar, u32 addr)
{
u32 cid = BMI_SET_APP_START;
int ret;
u32 offset;
u16 size;
if (ar->bmi.done_sent) {
ath6kl_err("bmi done sent already, cmd %d disallowed\n", cid);
return -EACCES;
}
size = sizeof(cid) + sizeof(addr);
if (size > MAX_BMI_CMDBUF_SZ) {
WARN_ON(1);
return -EINVAL;
}
memset(ar->bmi.cmd_buf, 0, size);
ath6kl_dbg(ATH6KL_DBG_BMI, "bmi set app start: addr: 0x%x\n", addr);
offset = 0;
memcpy(&(ar->bmi.cmd_buf[offset]), &cid, sizeof(cid));
offset += sizeof(cid);
memcpy(&(ar->bmi.cmd_buf[offset]), &addr, sizeof(addr));
offset += sizeof(addr);
ret = ath6kl_bmi_send_buf(ar, ar->bmi.cmd_buf, offset);
if (ret) {
ath6kl_err("Unable to write to the device: %d\n", ret);
return ret;
}
return 0;
}
int ath6kl_bmi_reg_read(struct ath6kl *ar, u32 addr, u32 *param)
{
u32 cid = BMI_READ_SOC_REGISTER;
int ret;
u32 offset;
u16 size;
if (ar->bmi.done_sent) {
ath6kl_err("bmi done sent already, cmd %d disallowed\n", cid);
return -EACCES;
}
size = sizeof(cid) + sizeof(addr);
if (size > MAX_BMI_CMDBUF_SZ) {
WARN_ON(1);
return -EINVAL;
}
memset(ar->bmi.cmd_buf, 0, size);
ath6kl_dbg(ATH6KL_DBG_BMI, "bmi read SOC reg: addr: 0x%x\n", addr);
offset = 0;
memcpy(&(ar->bmi.cmd_buf[offset]), &cid, sizeof(cid));
offset += sizeof(cid);
memcpy(&(ar->bmi.cmd_buf[offset]), &addr, sizeof(addr));
offset += sizeof(addr);
ret = ath6kl_bmi_send_buf(ar, ar->bmi.cmd_buf, offset);
if (ret) {
ath6kl_err("Unable to write to the device: %d\n", ret);
return ret;
}
ret = ath6kl_bmi_recv_buf(ar, ar->bmi.cmd_buf, sizeof(*param));
if (ret) {
ath6kl_err("Unable to read from the device: %d\n", ret);
return ret;
}
memcpy(param, ar->bmi.cmd_buf, sizeof(*param));
return 0;
}
int ath6kl_bmi_reg_write(struct ath6kl *ar, u32 addr, u32 param)
{
u32 cid = BMI_WRITE_SOC_REGISTER;
int ret;
u32 offset;
u16 size;
if (ar->bmi.done_sent) {
ath6kl_err("bmi done sent already, cmd %d disallowed\n", cid);
return -EACCES;
}
size = sizeof(cid) + sizeof(addr) + sizeof(param);
if (size > MAX_BMI_CMDBUF_SZ) {
WARN_ON(1);
return -EINVAL;
}
memset(ar->bmi.cmd_buf, 0, size);
ath6kl_dbg(ATH6KL_DBG_BMI,
"bmi write SOC reg: addr: 0x%x, param: %d\n",
addr, param);
offset = 0;
memcpy(&(ar->bmi.cmd_buf[offset]), &cid, sizeof(cid));
offset += sizeof(cid);
memcpy(&(ar->bmi.cmd_buf[offset]), &addr, sizeof(addr));
offset += sizeof(addr);
memcpy(&(ar->bmi.cmd_buf[offset]), &param, sizeof(param));
offset += sizeof(param);
ret = ath6kl_bmi_send_buf(ar, ar->bmi.cmd_buf, offset);
if (ret) {
ath6kl_err("Unable to write to the device: %d\n", ret);
return ret;
}
return 0;
}
int ath6kl_bmi_lz_data(struct ath6kl *ar, u8 *buf, u32 len)
{
u32 cid = BMI_LZ_DATA;
int ret;
u32 offset;
u32 len_remain, tx_len;
const u32 header = sizeof(cid) + sizeof(len);
u16 size;
if (ar->bmi.done_sent) {
ath6kl_err("bmi done sent already, cmd %d disallowed\n", cid);
return -EACCES;
}
size = BMI_DATASZ_MAX + header;
if (size > MAX_BMI_CMDBUF_SZ) {
WARN_ON(1);
return -EINVAL;
}
memset(ar->bmi.cmd_buf, 0, size);
ath6kl_dbg(ATH6KL_DBG_BMI, "bmi send LZ data: len: %d)\n",
len);
len_remain = len;
while (len_remain) {
tx_len = (len_remain < (BMI_DATASZ_MAX - header)) ?
len_remain : (BMI_DATASZ_MAX - header);
offset = 0;
memcpy(&(ar->bmi.cmd_buf[offset]), &cid, sizeof(cid));
offset += sizeof(cid);
memcpy(&(ar->bmi.cmd_buf[offset]), &tx_len, sizeof(tx_len));
offset += sizeof(tx_len);
memcpy(&(ar->bmi.cmd_buf[offset]), &buf[len - len_remain],
tx_len);
offset += tx_len;
ret = ath6kl_bmi_send_buf(ar, ar->bmi.cmd_buf, offset);
if (ret) {
ath6kl_err("Unable to write to the device: %d\n",
ret);
return ret;
}
len_remain -= tx_len;
}
return 0;
}
int ath6kl_bmi_lz_stream_start(struct ath6kl *ar, u32 addr)
{
u32 cid = BMI_LZ_STREAM_START;
int ret;
u32 offset;
u16 size;
if (ar->bmi.done_sent) {
ath6kl_err("bmi done sent already, cmd %d disallowed\n", cid);
return -EACCES;
}
size = sizeof(cid) + sizeof(addr);
if (size > MAX_BMI_CMDBUF_SZ) {
WARN_ON(1);
return -EINVAL;
}
memset(ar->bmi.cmd_buf, 0, size);
ath6kl_dbg(ATH6KL_DBG_BMI,
"bmi LZ stream start: addr: 0x%x)\n",
addr);
offset = 0;
memcpy(&(ar->bmi.cmd_buf[offset]), &cid, sizeof(cid));
offset += sizeof(cid);
memcpy(&(ar->bmi.cmd_buf[offset]), &addr, sizeof(addr));
offset += sizeof(addr);
ret = ath6kl_bmi_send_buf(ar, ar->bmi.cmd_buf, offset);
if (ret) {
ath6kl_err("Unable to start LZ stream to the device: %d\n",
ret);
return ret;
}
return 0;
}
int ath6kl_bmi_fast_download(struct ath6kl *ar, u32 addr, u8 *buf, u32 len)
{
int ret;
u32 last_word = 0;
u32 last_word_offset = len & ~0x3;
u32 unaligned_bytes = len & 0x3;
ret = ath6kl_bmi_lz_stream_start(ar, addr);
if (ret)
return ret;
if (unaligned_bytes) {
/* copy the last word into a zero padded buffer */
memcpy(&last_word, &buf[last_word_offset], unaligned_bytes);
}
ret = ath6kl_bmi_lz_data(ar, buf, last_word_offset);
if (ret)
return ret;
if (unaligned_bytes)
ret = ath6kl_bmi_lz_data(ar, (u8 *)&last_word, 4);
if (!ret) {
/* Close compressed stream and open a new (fake) one.
* This serves mainly to flush Target caches. */
ret = ath6kl_bmi_lz_stream_start(ar, 0x00);
}
return ret;
}
int ath6kl_bmi_init(struct ath6kl *ar)
{
ar->bmi.cmd_buf = kzalloc(MAX_BMI_CMDBUF_SZ, GFP_ATOMIC);
if (!ar->bmi.cmd_buf)
return -ENOMEM;
return 0;
}
void ath6kl_bmi_cleanup(struct ath6kl *ar)
{
kfree(ar->bmi.cmd_buf);
ar->bmi.cmd_buf = NULL;
}