From cd8f438405032ac8ff88bd8f2eca5e0c0063b14b Mon Sep 17 00:00:00 2001 From: Emmanuel Grumbach Date: Thu, 29 Jan 2015 21:34:00 +0200 Subject: [PATCH] iwlwifi: pcie: disable the SCD_BASE_ADDR when we resume from WoWLAN The base address of the scheduler in the device's memory (SRAM) comes from two different sources. The periphery register and the alive notification from the firmware. We have a check in iwl_pcie_tx_start that ensures that they are the same. When we resume from WoWLAN, the firmware may have crashed for whatever reason. In that case, the whole device may be reset which means that the periphery register will hold a meaningless value. When we come to compare trans_pcie->scd_base_addr (which really holds the value we had when we loaded the WoWLAN firmware upon suspend) and the current value of the register, we don't see a match unsurprisingly. Trick the check to avoid a loud yet harmless WARN. Note that when the WoWLAN has crashed, we will see that in iwl_trans_pcie_d3_resume which will let the op_mode know. Once the op_mode is informed that the WowLAN firmware has crashed, it can't do much besides resetting the whole device. CC: Reviewed-by: Johannes Berg Signed-off-by: Emmanuel Grumbach --- drivers/net/wireless/iwlwifi/pcie/tx.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/net/wireless/iwlwifi/pcie/tx.c b/drivers/net/wireless/iwlwifi/pcie/tx.c index 0a9408378707..59aefa43ea85 100644 --- a/drivers/net/wireless/iwlwifi/pcie/tx.c +++ b/drivers/net/wireless/iwlwifi/pcie/tx.c @@ -716,7 +716,12 @@ void iwl_trans_pcie_tx_reset(struct iwl_trans *trans) iwl_write_direct32(trans, FH_KW_MEM_ADDR_REG, trans_pcie->kw.dma >> 4); - iwl_pcie_tx_start(trans, trans_pcie->scd_base_addr); + /* + * Send 0 as the scd_base_addr since the device may have be reset + * while we were in WoWLAN in which case SCD_SRAM_BASE_ADDR will + * contain garbage. + */ + iwl_pcie_tx_start(trans, 0); } /*