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

[Alistair Popple]

On Monday, 20 May 2019 3:32:48 PM AEST Andrew Donnellan wrote:
> On 20/5/19 3:32 pm, Andrew Donnellan wrote:
> > On 20/5/19 2:22 pm, 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.
> >> 
> >> Signed-off-by: Alexey Kardashevskiy <aik at ozlabs.ru>
> > 
> > Oh yes that current code looks VERY wrong.
> > 
> > Reviewed-by: Andrew Donnellan <ajd at linux.ibm.com>
> 
> (does this need to go to stable?)

Probably. I'm not sure how this hasn't caused any issues before now.

- Alistair

> >> ---
> >>   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;
> >>       }