iwlwifi: mvm: dump Rx FIFO when the firmware asserts

The Rx FIFO includes valuable data - dump it when the FW
asserts. Also - free the SRAM and Rx FIFO when we create
the file, and don't collect new SRAM / Rx FIFO if the
previous file hasn't been collected through debugfs yet.

Also - add a comment to saying that the ASSERT output should
not be modified since we have automatic scripts that monitor
this output.

Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

1 files changed, 45 insertions, 1 deletions

diff --git a/drivers/net/wireless/iwlwifi/mvm/utils.c b/drivers/net/wireless/iwlwifi/mvm/utils.c
index d619851745a1..c5f4532cafa9 100644
--- a/drivers/net/wireless/iwlwifi/mvm/utils.c
+++ b/drivers/net/wireless/iwlwifi/mvm/utils.c
@@ -64,6 +64,7 @@
 
 #include "iwl-debug.h"
 #include "iwl-io.h"
+#include "iwl-prph.h"
 
 #include "mvm.h"
 #include "fw-api-rs.h"
@@ -469,6 +470,8 @@ void iwl_mvm_dump_nic_error_log(struct iwl_mvm *mvm)
 			mvm->status, table.valid);
 	}
 
+	/* Do not change this output - scripts rely on it */
+
 	IWL_ERR(mvm, "Loaded firmware version: %s\n", mvm->fw->fw_version);
 
 	trace_iwlwifi_dev_ucode_error(trans->dev, table.error_id, table.tsf_low,
@@ -522,7 +525,7 @@ void iwl_mvm_fw_error_sram_dump(struct iwl_mvm *mvm)
 	u32 ofs, sram_len;
 	void *sram;
 
-	if (!mvm->ucode_loaded || mvm->fw_error_sram)
+	if (!mvm->ucode_loaded || mvm->fw_error_sram || mvm->fw_error_dump)
 		return;
 
 	img = &mvm->fw->img[mvm->cur_ucode];
@@ -538,6 +541,47 @@ void iwl_mvm_fw_error_sram_dump(struct iwl_mvm *mvm)
 	mvm->fw_error_sram_len = sram_len;
 }
 
+void iwl_mvm_fw_error_rxf_dump(struct iwl_mvm *mvm)
+{
+	int i, reg_val;
+	unsigned long flags;
+
+	if (!mvm->ucode_loaded || mvm->fw_error_rxf || mvm->fw_error_dump)
+		return;
+
+	/* reading buffer size */
+	reg_val = iwl_trans_read_prph(mvm->trans, RXF_SIZE_ADDR);
+	mvm->fw_error_rxf_len =
+		(reg_val & RXF_SIZE_BYTE_CNT_MSK) >> RXF_SIZE_BYTE_CND_POS;
+
+	/* the register holds the value divided by 128 */
+	mvm->fw_error_rxf_len = mvm->fw_error_rxf_len << 7;
+
+	if (!mvm->fw_error_rxf_len)
+		return;
+
+	mvm->fw_error_rxf =  kzalloc(mvm->fw_error_rxf_len, GFP_ATOMIC);
+	if (!mvm->fw_error_rxf) {
+		mvm->fw_error_rxf_len = 0;
+		return;
+	}
+
+	if (!iwl_trans_grab_nic_access(mvm->trans, false, &flags)) {
+		kfree(mvm->fw_error_rxf);
+		mvm->fw_error_rxf = NULL;
+		mvm->fw_error_rxf_len = 0;
+		return;
+	}
+
+	for (i = 0; i < (mvm->fw_error_rxf_len / sizeof(u32)); i++) {
+		iwl_trans_write_prph(mvm->trans, RXF_LD_FENCE_OFFSET_ADDR,
+				     i * sizeof(u32));
+		mvm->fw_error_rxf[i] =
+			iwl_trans_read_prph(mvm->trans, RXF_FIFO_RD_FENCE_ADDR);
+	}
+	iwl_trans_release_nic_access(mvm->trans, &flags);
+}
+
 /**
  * iwl_mvm_send_lq_cmd() - Send link quality command
  * @init: This command is sent as part of station initialization right