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> --- drivers/fsi/fsi-occ.c | 66 +++++++++++++++++++++++++++++++------------ 1 file changed, 48 insertions(+), 18 deletions(-) diff --git a/drivers/fsi/fsi-occ.c b/drivers/fsi/fsi-occ.c index b4302776026d..7eaab1be0aa4 100644 --- a/drivers/fsi/fsi-occ.c +++ b/drivers/fsi/fsi-occ.c @@ -46,6 +46,9 @@ 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; @@ -208,6 +211,22 @@ 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) +{ + if (resp_len > parsed_len) { + size_t dh = resp_len - parsed_len; + size_t ffdc_len = (dh - 1) * 4; /* SBE words are four bytes */ + __be32 *ffdc = &resp[parsed_len]; + + 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) { @@ -236,7 +255,7 @@ 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]; @@ -271,16 +290,17 @@ 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); @@ -296,7 +316,7 @@ 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; @@ -343,18 +363,19 @@ 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]); @@ -372,7 +393,7 @@ 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; @@ -403,18 +424,19 @@ 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]); @@ -437,6 +459,7 @@ 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; @@ -445,11 +468,13 @@ 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; } @@ -459,6 +484,10 @@ 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 @@ -509,7 +538,7 @@ 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; } @@ -525,10 +554,11 @@ 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; 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