If the SBEFIFO response indicates an error, store the response in the
user buffer and return an error. Previously, the user had no way of
obtaining the SBEFIFO FFDC.
Signed-off-by: Eddie James <eajames@xxxxxxxxxxxxx>
---
Changes since v1:
- Don't store any magic value; only return non-zero resp_len in the error
case if there is FFDC
drivers/fsi/fsi-occ.c | 66 ++++++++++++++++++++++++++++++-------------
1 file changed, 47 insertions(+), 19 deletions(-)
diff --git a/drivers/fsi/fsi-occ.c b/drivers/fsi/fsi-occ.c
index ace3ec7767e5..1d5f6fdc2a34 100644
--- a/drivers/fsi/fsi-occ.c
+++ b/drivers/fsi/fsi-occ.c
@@ -55,6 +55,9 @@ struct occ {
int idx;
u8 sequence_number;
void *buffer;
+ void *client_buffer;
+ size_t client_buffer_size;
+ size_t client_response_size;
enum versions version;
struct miscdevice mdev;
struct mutex occ_lock;
@@ -217,6 +220,20 @@ static const struct file_operations occ_fops = {
.release = occ_release,
};
+static void occ_save_ffdc(struct occ *occ, __be32 *resp, size_t parsed_len,
+ size_t resp_len)
+{
+ size_t dh = resp_len - parsed_len;
+ size_t ffdc_len = (dh - 1) * 4;
+ __be32 *ffdc = &resp[resp_len - dh];
+
+ if (ffdc_len > occ->client_buffer_size)
+ ffdc_len = occ->client_buffer_size;
+
+ memcpy(occ->client_buffer, ffdc, ffdc_len);
+ occ->client_response_size = ffdc_len;
+}
+
static int occ_verify_checksum(struct occ *occ, struct occ_response *resp,
u16 data_length)
{
@@ -245,7 +262,7 @@ static int occ_verify_checksum(struct occ *occ, struct occ_response *resp,
static int occ_getsram(struct occ *occ, u32 offset, void *data, ssize_t len)
{
u32 data_len = ((len + 7) / 8) * 8; /* must be multiples of 8 B */
- size_t cmd_len, resp_data_len;
+ size_t cmd_len, parsed_len, resp_data_len;
size_t resp_len = OCC_MAX_RESP_WORDS;
__be32 *resp = occ->buffer;
__be32 cmd[6];
@@ -280,16 +297,17 @@ static int occ_getsram(struct occ *occ, u32 offset, void *data, ssize_t len)
return rc;
rc = sbefifo_parse_status(occ->sbefifo, SBEFIFO_CMD_GET_OCC_SRAM,
- resp, resp_len, &resp_len);
+ resp, resp_len, &parsed_len);
if (rc > 0) {
dev_err(occ->dev, "SRAM read returned failure status: %08x\n",
rc);
- return -EBADMSG;
+ occ_save_ffdc(occ, resp, parsed_len, resp_len);
+ return -ECOMM;
} else if (rc) {
return rc;
}
- resp_data_len = be32_to_cpu(resp[resp_len - 1]);
+ resp_data_len = be32_to_cpu(resp[parsed_len - 1]);
if (resp_data_len != data_len) {
dev_err(occ->dev, "SRAM read expected %d bytes got %zd\n",
data_len, resp_data_len);
@@ -305,7 +323,7 @@ static int occ_putsram(struct occ *occ, const void *data, ssize_t len,
u8 seq_no, u16 checksum)
{
u32 data_len = ((len + 7) / 8) * 8; /* must be multiples of 8 B */
- size_t cmd_len, resp_data_len;
+ size_t cmd_len, parsed_len, resp_data_len;
size_t resp_len = OCC_MAX_RESP_WORDS;
__be32 *buf = occ->buffer;
u8 *byte_buf;
@@ -366,18 +384,19 @@ static int occ_putsram(struct occ *occ, const void *data, ssize_t len,
return rc;
rc = sbefifo_parse_status(occ->sbefifo, SBEFIFO_CMD_PUT_OCC_SRAM,
- buf, resp_len, &resp_len);
+ buf, resp_len, &parsed_len);
if (rc > 0) {
dev_err(occ->dev, "SRAM write returned failure status: %08x\n",
rc);
- return -EBADMSG;
+ occ_save_ffdc(occ, buf, parsed_len, resp_len);
+ return -ECOMM;
} else if (rc) {
return rc;
}
- if (resp_len != 1) {
+ if (parsed_len != 1) {
dev_err(occ->dev, "SRAM write response length invalid: %zd\n",
- resp_len);
+ parsed_len);
rc = -EBADMSG;
} else {
resp_data_len = be32_to_cpu(buf[0]);
@@ -395,7 +414,7 @@ static int occ_putsram(struct occ *occ, const void *data, ssize_t len,
static int occ_trigger_attn(struct occ *occ)
{
__be32 *buf = occ->buffer;
- size_t cmd_len, resp_data_len;
+ size_t cmd_len, parsed_len, resp_data_len;
size_t resp_len = OCC_MAX_RESP_WORDS;
int idx = 0, rc;
@@ -426,18 +445,19 @@ static int occ_trigger_attn(struct occ *occ)
return rc;
rc = sbefifo_parse_status(occ->sbefifo, SBEFIFO_CMD_PUT_OCC_SRAM,
- buf, resp_len, &resp_len);
+ buf, resp_len, &parsed_len);
if (rc > 0) {
dev_err(occ->dev, "SRAM attn returned failure status: %08x\n",
rc);
- return -EBADMSG;
+ occ_save_ffdc(occ, buf, parsed_len, resp_len);
+ return -ECOMM;
} else if (rc) {
return rc;
}
- if (resp_len != 1) {
+ if (parsed_len != 1) {
dev_err(occ->dev, "SRAM attn response length invalid: %zd\n",
- resp_len);
+ parsed_len);
rc = -EBADMSG;
} else {
resp_data_len = be32_to_cpu(buf[0]);
@@ -460,6 +480,7 @@ int fsi_occ_submit(struct device *dev, const void *request, size_t req_len,
msecs_to_jiffies(OCC_CMD_IN_PRG_WAIT_MS);
struct occ *occ = dev_get_drvdata(dev);
struct occ_response *resp = response;
+ size_t user_resp_len = *resp_len;
u8 seq_no;
u16 checksum = 0;
u16 resp_data_length;
@@ -468,11 +489,13 @@ int fsi_occ_submit(struct device *dev, const void *request, size_t req_len,
int rc;
size_t i;
+ *resp_len = 0;
+
if (!occ)
return -ENODEV;
- if (*resp_len < 7) {
- dev_dbg(dev, "Bad resplen %zd\n", *resp_len);
+ if (user_resp_len < 7) {
+ dev_dbg(dev, "Bad resplen %zd\n", user_resp_len);
return -EINVAL;
}
@@ -482,6 +505,10 @@ int fsi_occ_submit(struct device *dev, const void *request, size_t req_len,
mutex_lock(&occ->occ_lock);
+ occ->client_buffer = response;
+ occ->client_buffer_size = user_resp_len;
+ occ->client_response_size = 0;
+
/*
* Get a sequence number and update the counter. Avoid a sequence
* number of 0 which would pass the response check below even if the
@@ -532,7 +559,7 @@ int fsi_occ_submit(struct device *dev, const void *request, size_t req_len,
resp_data_length = get_unaligned_be16(&resp->data_length);
/* Message size is data length + 5 bytes header + 2 bytes checksum */
- if ((resp_data_length + 7) > *resp_len) {
+ if ((resp_data_length + 7) > user_resp_len) {
rc = -EMSGSIZE;
goto done;
}
@@ -548,7 +575,7 @@ int fsi_occ_submit(struct device *dev, const void *request, size_t req_len,
goto done;
}
- *resp_len = resp_data_length + 7;
+ occ->client_response_size = resp_data_length + 7;
{
DEFINE_DYNAMIC_DEBUG_METADATA(ddm_occ_rsp,
@@ -560,7 +587,7 @@ int fsi_occ_submit(struct device *dev, const void *request, size_t req_len,
DYNAMIC_DEBUG_BRANCH(ddm_occ_rsp)) {
char prefix[64];
size_t l = DYNAMIC_DEBUG_BRANCH(ddm_occ_full_rsp) ?
- *resp_len : 16;
+ occ->client_response_size : 16;
snprintf(prefix, sizeof(prefix), "%s %s: rsp ",
dev_driver_string(occ->dev),
@@ -573,6 +600,7 @@ int fsi_occ_submit(struct device *dev, const void *request, size_t req_len,
rc = occ_verify_checksum(occ, resp, resp_data_length);
done:
+ *resp_len = occ->client_response_size;
mutex_unlock(&occ->occ_lock);
return rc;
--
2.27.0
