[Skiboot] [PATCH skiboot] npu2: Fix clearing the FIR bits

[Alexey Kardashevskiy]

On 20/05/2019 15:07, Alistair Popple wrote:
> On Monday, 20 May 2019 2:22:01 PM AEST Alexey Kardashevskiy wrote:
>> FIR registers are SCOM-only so they cannot be accesses with the indirect
>> write, and yet we use SCOM-based addresses for these; fix this.
> 
> Thanks for fixing, although I don't entirely follow the commit message - I 
> think you mean "and yet we use indirect addresses for these". It might be 
> worth mentioning what you mean by indirect too (ie. npu2_write()) .


Writing to SCOM using its "SCOM address" via xscom_base is direct.
Writing to SCOM using its "NPURING" alias via
NPU2_MISC_SCOM_IND_SCOM_ADDR is indirect.

What am I missing here and what are the well established terms then?


> However the fix itself is good.
> 
> Reviewed-By: Alistair Popple <alistair at popple.id.au>
>  
>> Signed-off-by: Alexey Kardashevskiy <aik at ozlabs.ru>
>> ---
>>  hw/npu2-hw-procedures.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/hw/npu2-hw-procedures.c b/hw/npu2-hw-procedures.c
>> index b671b8ac00e3..e1f5e8d64c27 100644
>> --- a/hw/npu2-hw-procedures.c
>> +++ b/hw/npu2-hw-procedures.c
>> @@ -331,7 +331,7 @@ static uint32_t reset_ntl_release(struct npu2_dev *ndev)
>> npu2_fir = 0;
>>
>>  	for (i = 0; i < NPU2_TOTAL_FIR_REGISTERS; i++) {
>> -		npu2_write(ndev->npu, npu2_fir_addr, npu2_fir);
>> +		xscom_write(ndev->npu->chip_id, npu2_fir_addr, npu2_fir);
>>  		npu2_fir_addr += NPU2_FIR_OFFSET;
>>
>>  	}
> 
> 

-- 
Alexey