iwlwifi: mvm: send udev event upon firmware error to dump logs

When the firmware asserts, the driver will dump the firmware
state to an internal buffer. This buffer is kept aside until
it is dumped through debugfs. Once an external application
fetched the data, the buffer is freed and a new buffer can
be allocated in case another assert occurs.

A udev event is sent to trigger an external application.

A simple rule like:
DRIVER=="iwlwifi", ACTION=="change", RUN+="/sbin/dump_sram.sh"

can fetch the data from debugfs.

Here is my dump_sram.sh:

phyname=$(basename ${DEVPATH})
date=$(date +%F_%H_%M)
filename=/var/log/iwl-sram-${phyname}-${date}.bin
cat /sys/kernel/debug/ieee80211/${phyname}/iwlwifi/iwlmvm/fw_error_dump > ${filename}

The current SRAM size is 80KB so, currently:
$ ls -lh iwl-sram-phy0-2014-03-16_13_14.bin
-rw-r--r-- 1 emmanuel emmanuel 81K Mar 16 13:15 iwl-sram-phy0-2014-03-16_13_14.bin

and after compression:
$ ls -lh iwl-sram-phy0-2014-03-16_13_14.bin.xz
-rw-r--r-- 1 emmanuel emmanuel 13K Mar 16 13:15 iwl-sram-phy0-2014-03-16_13_14.bin.xz

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

1 files changed, 7 insertions, 1 deletions

diff --git a/drivers/net/wireless/iwlwifi/mvm/mvm.h b/drivers/net/wireless/iwlwifi/mvm/mvm.h
index 46fe817..cb6dbb1 100644
--- a/drivers/net/wireless/iwlwifi/mvm/mvm.h
+++ b/drivers/net/wireless/iwlwifi/mvm/mvm.h
@@ -575,6 +575,9 @@ struct iwl_mvm {
 
 	/* -1 for always, 0 for never, >0 for that many times */
 	s8 restart_fw;
+	void *fw_error_dump;
+	void *fw_error_sram;
+	u32 fw_error_sram_len;
 
 	struct led_classdev led;
 
@@ -698,7 +701,10 @@ void iwl_mvm_hwrate_to_tx_rate(u32 rate_n_flags,
 			       struct ieee80211_tx_rate *r);
 u8 iwl_mvm_mac80211_idx_to_hwrate(int rate_idx);
 void iwl_mvm_dump_nic_error_log(struct iwl_mvm *mvm);
-void iwl_mvm_dump_sram(struct iwl_mvm *mvm);
+#ifdef CONFIG_IWLWIFI_DEBUGFS
+void iwl_mvm_fw_error_dump(struct iwl_mvm *mvm);
+void iwl_mvm_fw_error_sram_dump(struct iwl_mvm *mvm);
+#endif
 u8 first_antenna(u8 mask);
 u8 iwl_mvm_next_antenna(struct iwl_mvm *mvm, u8 valid, u8 last_idx);