Re: [PATCH 2/5] hw/ppc/pnv_xscom: PBA bar mask values are incorrect with homer/occ sizes

[Balamuruhan S <bala24@linux.ibm.com>]

On Wed, Nov 20, 2019 at 08:18:38AM +0100, Cédric Le Goater wrote:
> On 19/11/2019 18:50, Balamuruhan S wrote:
> > homer/occ sizes are calculated in skiboot with `(mask | 0xfffff) + 1`,
> > and from xscom access should return correct mask values instead of actual
> > sizes.
> > 
> > Signed-off-by: Cédric Le Goater <clg@kaod.org>
> > Signed-off-by: Balamuruhan S <bala24@linux.ibm.com>
> > ---
> >  hw/ppc/pnv_xscom.c | 10 ++++++----
> >  1 file changed, 6 insertions(+), 4 deletions(-)
> > 
> > diff --git a/hw/ppc/pnv_xscom.c b/hw/ppc/pnv_xscom.c
> > index f01d788a65..cdd5fa356e 100644
> > --- a/hw/ppc/pnv_xscom.c
> > +++ b/hw/ppc/pnv_xscom.c
> > @@ -46,6 +46,10 @@
> >  #define P9_PBA_BARMASK0                 0x5012b04
> >  #define P9_PBA_BARMASK2                 0x5012b06
> >  
> > +/* Mask to calculate Homer/Occ size */
> > +#define HOMER_SIZE_MASK                 0x0000000000300000ull
> > +#define OCC_SIZE_MASK                   0x0000000000700000ull
> > +
> 
> Can't we deduce these values from the size ? 

yes, that's a better way.

> 
> >  static void xscom_complete(CPUState *cs, uint64_t hmer_bits)
> >  {
> >      /*
> > @@ -90,9 +94,8 @@ static uint64_t xscom_read_default(PnvChip *chip, uint32_t pcba)
> >          return PNV_HOMER_BASE(chip);
> >  
> >      case P9_PBA_BARMASK0: /* P9 homer region size */
> > -        return PNV9_HOMER_SIZE;
> >      case P8_PBA_BARMASK0: /* P8 homer region size */
> > -        return PNV_HOMER_SIZE;
> > +        return HOMER_SIZE_MASK;
> 
> I would prefer to move all the HOMER accesses in a XSCOM region
> under the PnvHomer model than expanding the default handlers. 
> You will need a different set of handlers for P8 and P9 and a 
> different mapping address also. 
> 
> Could you do that please ? 

Sure Cedric, I can work on it.

>   
> >      case P9_PBA_BAR2: /* P9 occ common area */
> >          return PNV9_OCC_COMMON_AREA(chip);
> > @@ -100,9 +103,8 @@ static uint64_t xscom_read_default(PnvChip *chip, uint32_t pcba)
> >          return PNV_OCC_COMMON_AREA(chip);
> >  
> >      case P9_PBA_BARMASK2: /* P9 occ common area size */
> > -        return PNV9_OCC_COMMON_AREA_SIZE;
> >      case P8_PBA_BARMASK2: /* P8 occ common area size */
> 
> Shouldn't that be PBA_*3 under P8 ? 

:( It's a miss from me. Thanks!

> 
> C. 
> 
> > -        return PNV_OCC_COMMON_AREA_SIZE;
> > +        return OCC_SIZE_MASK;
> >  
> >      case 0x1010c00:     /* PIBAM FIR */
> >      case 0x1010c03:     /* PIBAM FIR MASK */
> > 
>