Re: [PATCH 1/2] x86/gpu: reserve ICL's graphics stolen memory

[Paulo Zanoni <paulo.r.zanoni@intel.com>]

Em Seg, 2018-05-07 às 11:46 +0300, Joonas Lahtinen escreveu:
> Ingo, do you prefer to merge through our tree with your ack?

Ping?

> 
> Quoting Paulo Zanoni (2018-05-04 23:32:51)
> > ICL changes the registers and addresses to 64 bits.
> > 
> > I also briefly looked at implementing an u64 version of the PCI
> > config
> > read functions, but I concluded this wouldn't be trivial, so it's
> > not
> > worth doing it for a single user that can't have any racing
> > problems
> > while reading the register in two separate operations.
> > 
> > v2:
> >  - Scrub the development (non-public) changelog (Joonas).
> >  - Remove the i915.ko bits so this can be easily backported in
> > order
> >    to properly avoid stolen memory even on machines without i915.ko
> >    (Joonas).
> >  - CC stable for the reasons above.
> > 
> > Issue: VIZ-9250
> 
> Fixes: 412310019a20 ("drm/i915/icl: Add initial Icelake
> definitions.")
> 
> > CC: stable@vger.kernel.org
> 
> This should not be needed, it was introduced in v4.17-rc1 only.
> 
> Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
> 
> Regards, Joonas
> 
> > Cc: Ingo Molnar <mingo@kernel.org>
> > Cc: H. Peter Anvin <hpa@zytor.com>
> > Cc: x86@kernel.org
> > Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
> > Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
> > Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
> > ---
> >  arch/x86/kernel/early-quirks.c | 18 ++++++++++++++++++
> >  include/drm/i915_drm.h         |  4 +++-
> >  2 files changed, 21 insertions(+), 1 deletion(-)
> > 
> > diff --git a/arch/x86/kernel/early-quirks.c
> > b/arch/x86/kernel/early-quirks.c
> > index bae0d32e327b..72c2cf961d44 100644
> > --- a/arch/x86/kernel/early-quirks.c
> > +++ b/arch/x86/kernel/early-quirks.c
> > @@ -340,6 +340,18 @@ static resource_size_t __init
> > gen3_stolen_base(int num, int slot, int func,
> >         return bsm & INTEL_BSM_MASK;
> >  }
> >  
> > +static resource_size_t __init gen11_stolen_base(int num, int slot,
> > int func,
> > +                                               resource_size_t
> > stolen_size)
> > +{
> > +       u64 bsm;
> > +
> > +       bsm = read_pci_config(num, slot, func,
> > INTEL_GEN11_BSM_DW0);
> > +       bsm &= INTEL_BSM_MASK;
> > +       bsm |= (u64)read_pci_config(num, slot, func,
> > INTEL_GEN11_BSM_DW1) << 32;
> > +
> > +       return bsm;
> > +}
> > +
> >  static resource_size_t __init i830_stolen_size(int num, int slot,
> > int func)
> >  {
> >         u16 gmch_ctrl;
> > @@ -500,6 +512,11 @@ static const struct intel_early_ops
> > chv_early_ops __initconst = {
> >         .stolen_size = chv_stolen_size,
> >  };
> >  
> > +static const struct intel_early_ops gen11_early_ops __initconst =
> > {
> > +       .stolen_base = gen11_stolen_base,
> > +       .stolen_size = gen9_stolen_size,
> > +};
> > +
> >  static const struct pci_device_id intel_early_ids[] __initconst =
> > {
> >         INTEL_I830_IDS(&i830_early_ops),
> >         INTEL_I845G_IDS(&i845_early_ops),
> > @@ -531,6 +548,7 @@ static const struct pci_device_id
> > intel_early_ids[] __initconst = {
> >         INTEL_CFL_IDS(&gen9_early_ops),
> >         INTEL_GLK_IDS(&gen9_early_ops),
> >         INTEL_CNL_IDS(&gen9_early_ops),
> > +       INTEL_ICL_11_IDS(&gen11_early_ops),
> >  };
> >  
> >  struct resource intel_graphics_stolen_res __ro_after_init =
> > DEFINE_RES_MEM(0, 0);
> > diff --git a/include/drm/i915_drm.h b/include/drm/i915_drm.h
> > index c9e5a6621b95..c44703f471b3 100644
> > --- a/include/drm/i915_drm.h
> > +++ b/include/drm/i915_drm.h
> > @@ -95,7 +95,9 @@ extern struct resource intel_graphics_stolen_res;
> >  #define    I845_TSEG_SIZE_512K (2 << 1)
> >  #define    I845_TSEG_SIZE_1M   (3 << 1)
> >  
> > -#define INTEL_BSM 0x5c
> > +#define INTEL_BSM              0x5c
> > +#define INTEL_GEN11_BSM_DW0    0xc0
> > +#define INTEL_GEN11_BSM_DW1    0xc4
> >  #define   INTEL_BSM_MASK       (-(1u << 20))
> >  
> >  #endif                         /* _I915_DRM_H_ */
> > -- 
> > 2.14.3
> >