Subject: Re: [PATCH v1] wifi: ath9k: fix AR9003 mac hardware hang check register offset calculation

From: Toke Høiland-Jørgensen <[email-masked]>
Date: Sat, 22 Apr 2023 12:18:03 +0200

Simon Horman <[email-masked]> writes:

> On Thu, Apr 20, 2023 at 10:43:16PM +0200, Peter Seiderer wrote:
>> Fix ath9k_hw_verify_hang()/ar9003_hw_detect_mac_hang() register offset
>> calculation (do not overflow the shift for the second register/queues
>> above five, use the register layout described in the comments above
>> ath9k_hw_verify_hang() instead).
>> 
>> Fixes: 222e04830ff0 ("ath9k: Fix MAC HW hang check for AR9003")
>> 
>> Reported-by: Gregg Wonderly <[email-masked]>
>> Link: https://lore.kernel.org/linux-wireless/[email-masked]/
>> Signed-off-by: Peter Seiderer <[email-masked]>
>> ---
>> Notes:
>>   - tested with MikroTik R11e-5HnD/Atheros AR9300 Rev:4 (lspci: 168c:0033
>>     Qualcomm Atheros AR958x 802.11abgn Wireless Network Adapter (rev 01))
>>     card
>> ---
>>  drivers/net/wireless/ath/ath9k/ar9003_hw.c | 27 ++++++++++++++--------
>>  1 file changed, 18 insertions(+), 9 deletions(-)
>> 
>> diff --git a/drivers/net/wireless/ath/ath9k/ar9003_hw.c b/drivers/net/wireless/ath/ath9k/ar9003_hw.c
>> index 4f27a9fb1482..0ccf13a35fb4 100644
>> --- a/drivers/net/wireless/ath/ath9k/ar9003_hw.c
>> +++ b/drivers/net/wireless/ath/ath9k/ar9003_hw.c
>> @@ -1099,17 +1099,22 @@ static bool ath9k_hw_verify_hang(struct ath_hw *ah, unsigned int queue)
>>  {
>>  	u32 dma_dbg_chain, dma_dbg_complete;
>>  	u8 dcu_chain_state, dcu_complete_state;
>> +	unsigned int dbg_reg, reg_offset;
>>  	int i;
>>  
>> -	for (i = 0; i < NUM_STATUS_READS; i++) {
>> -		if (queue < 6)
>> -			dma_dbg_chain = REG_READ(ah, AR_DMADBG_4);
>> -		else
>> -			dma_dbg_chain = REG_READ(ah, AR_DMADBG_5);
>> +	if (queue < 6) {
>> +		dbg_reg = AR_DMADBG_4;
>> +		reg_offset = i * 5;
>
> Hi Peter,
>
> unless my eyes are deceiving me, i is not initialised here.

Nice catch! Hmm, I wonder why my test compile didn't complain about
that? Or maybe it did and I overlooked it? Anyway, Kalle, I already
delegated this patch to you in patchwork, so please drop it and I'll try
to do better on reviewing the next one :)

-Toke