On Mon, Sep 12, 2022 at 10:12:57PM +0200, Andi Shyti wrote:
Hi Lucas, On Mon, Sep 12, 2022 at 11:12:47AM -0700, Lucas De Marchi wrote:On Mon, Sep 12, 2022 at 06:59:53PM +0200, Andi Shyti wrote: > Hi Lucas, > > On Mon, Sep 12, 2022 at 09:19:38AM -0700, Lucas De Marchi wrote: > > Support for reading the fuses to check what are the Link Copy engines > > was added in commit ad5f74f34201 ("drm/i915/pvc: read fuses for link > > copy engines"). However they were added unconditionally because the > > FUSE3 register is present since graphics version 10. > > > > However the bitfield with meml3 fuses only exists since graphics version > > 12. Moreover, Link Copy engines are currently only available in PVC. > > Tying additional copy engines to the meml3 fuses is not correct for > > other platforms. > > > > Make sure there is a check for `12.60 <= ver < 12.70`. Later platforms > > may extend this function later if it's needed to fuse off copy engines. > > > > Currently it's harmless as the Link Copy engines are still not exported: > > info->engine_mask only has BCS0 set and the register is only read for > > platforms that do have it. > > > > Signed-off-by: Lucas De Marchi <lucas.demarchi@xxxxxxxxx> > > > > diff --git a/drivers/gpu/drm/i915/gt/intel_engine_cs.c b/drivers/gpu/drm/i915/gt/intel_engine_cs.c > > index 814f83b5fe59..1f7188129cd1 100644 > > --- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c > > +++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c > > @@ -764,6 +764,10 @@ static void engine_mask_apply_copy_fuses(struct intel_gt *gt) > > unsigned long meml3_mask; > > unsigned long quad; > > > > + if (!(GRAPHICS_VER_FULL(i915) >= IP_VER(12, 60) && > > + GRAPHICS_VER_FULL(i915) < IP_VER(12, 70))) > > + return; > > + > > Isn't it easier if you wrote > > if (GRAPHICS_VER_FULL(i915) < IP_VER(12, 60) || > GRAPHICS_VER_FULL(i915) >= IP_VER(12, 70)) > return; > > ? > > You save a parenthesis and a negation '!'. but that makes it wrong. I'd really want the range 12.60 <= version < 12.70, so it applies to PVC but is then disabled again for MTL.But it's negated... so that if it's not in the range, it's outside of the range... right? NOT(12.60 <= ver < 12.70) <--- you wrote is the same as: ver < 12.60 or ver >= 12.70 <--- I suggested and it would mean (just to see if I'm not getting confused by something and the negations do always confuse me): 12.60 12.70 return | | return ver: ------------[--------------[--------------- But it's the same, taht's why I r-b it anyway.
yeah, when I read your reply I missed the fact you changed the comparisons <=, > thanks Lucas De Marchi
