RE: [PATCH 1/8] EDAC/amd64: Fix number of DIMMs and Chip Select bases/masks on Family17h

[Ghannam, Yazen]

> -----Original Message-----
> From: Borislav Petkov <bp@xxxxxxxxx>
> Sent: Thursday, June 13, 2019 8:58 AM
> To: Ghannam, Yazen <Yazen.Ghannam@xxxxxxx>
> Cc: linux-edac@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH 1/8] EDAC/amd64: Fix number of DIMMs and Chip Select bases/masks on Family17h
> 
> On Fri, May 31, 2019 at 11:45:11PM +0000, Ghannam, Yazen wrote:
> > From: Yazen Ghannam <yazen.ghannam@xxxxxxx>
> >
> > ...because AMD Family 17h systems support 2 DIMMs, 4 CS bases, and 2 CS
> > masks per channel.
> >
> > Fixes: 07ed82ef93d6 ("EDAC, amd64: Add Fam17h debug output")
> > Signed-off-by: Yazen Ghannam <yazen.ghannam@xxxxxxx>
> > ---
> >  drivers/edac/amd64_edac.c | 5 ++++-
> >  1 file changed, 4 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/edac/amd64_edac.c b/drivers/edac/amd64_edac.c
> > index 873437be86d9..9fa2f205f05c 100644
> > --- a/drivers/edac/amd64_edac.c
> > +++ b/drivers/edac/amd64_edac.c
> > @@ -810,7 +810,7 @@ static void debug_display_dimm_sizes_df(struct amd64_pvt *pvt, u8 ctrl)
> >
> >  	edac_printk(KERN_DEBUG, EDAC_MC, "UMC%d chip selects:\n", ctrl);
> >
> > -	for (dimm = 0; dimm < 4; dimm++) {
> > +	for (dimm = 0; dimm < 2; dimm++) {
> >  		size0 = 0;
> >  		cs0 = dimm * 2;
> >
> > @@ -942,6 +942,9 @@ static void prep_chip_selects(struct amd64_pvt *pvt)
> >  	} else if (pvt->fam == 0x15 && pvt->model == 0x30) {
> >  		pvt->csels[0].b_cnt = pvt->csels[1].b_cnt = 4;
> >  		pvt->csels[0].m_cnt = pvt->csels[1].m_cnt = 2;
> > +	} else if (pvt->fam >= 0x17) {
> > +		pvt->csels[0].b_cnt = pvt->csels[1].b_cnt = 4;
> > +		pvt->csels[0].m_cnt = pvt->csels[1].m_cnt = 2;
> 
> I guess it is about time that function gets turned into a switch-case so
> that the assignment lines do not get duplicated.
> 

Okay, I'll write up a patch for that.

Do you have any tips on how to handle it? I'm thinking it may be tricky because of the ranges and multiple variables.

Thanks,
Yazen