Re: [PATCH v5 4/4] hw/ssi/pnv_spi: Put a limit to RDR match failures

[Chalapathi V <chalapathi.v@linux.ibm.com>]

On 27-02-2025 07:26, Nicholas Piggin wrote:
> On Sat Jan 4, 2025 at 2:18 AM AEST, Chalapathi V wrote:
>> There is a possibility that SPI controller can get into loop due to indefinite
>> RDR match failures. Hence put a limit to failures and stop the sequencer.
>>
>> Signed-off-by: Chalapathi V <chalapathi.v@linux.ibm.com>
>> ---
>>   hw/ssi/pnv_spi.c | 11 +++++++++++
>>   1 file changed, 11 insertions(+)
>>
>> diff --git a/hw/ssi/pnv_spi.c b/hw/ssi/pnv_spi.c
>> index 41beb559c6..d605fa8b46 100644
>> --- a/hw/ssi/pnv_spi.c
>> +++ b/hw/ssi/pnv_spi.c
>> @@ -20,6 +20,7 @@
>>   #define PNV_SPI_OPCODE_LO_NIBBLE(x) (x & 0x0F)
>>   #define PNV_SPI_MASKED_OPCODE(x) (x & 0xF0)
>>   #define PNV_SPI_FIFO_SIZE 16
>> +#define RDR_MATCH_FAILURE_LIMIT 16
>>   
>>   /*
>>    * Macro from include/hw/ppc/fdt.h
>> @@ -838,21 +839,31 @@ static void operation_sequencer(PnvSpi *s)
>>                */
>>               if (GETFIELD(SPI_STS_RDR_FULL, s->status) == 1) {
>>                   bool rdr_matched = false;
>> +                static int fail_count;
> This will be shared by SPI instances, is that okay or should it be
> in PnvSpi?
>
> Other than that, looks good.
This should be in PnvSpi. Will update in V6. Thank You.
> Reviewed-by: Nicholas Piggin <npiggin@gmail.com>