Re: [Intel-gfx] [PATCH v4 08/18] drm/i915/xehp: Changes to ss/eu definitions

Souza, Jose
2021-08-04T00:17:55Z

On Thu, 2021-07-29 at 09:59 -0700, Matt Roper wrote:
> From: Matthew Auld <matthew.auld@intel.com>
>
> Xe_HP no longer has "slices" in the same way that old platforms did.
> There are new concepts (gslices, cslices, mslices) that apply in various
> contexts, but for the purposes of fusing slices no longer exist and we
> just have one large pool of dual-subslices (DSS) to work with.
> Furthermore, the meaning of the DSS fuse is inverted compared to past
> platforms --- it now specifies which DSS are enabled rather than which
> ones are disabled.

Reviewed-by: José Roberto de Souza <jose.souza@intel.com>

>
> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
> Cc: Lucas De Marchi <lucas.demarchi@intel.com>
> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
> Signed-off-by: Matthew Auld <matthew.auld@intel.com>
> Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
> Signed-off-by: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
> Signed-off-by: Stuart Summers <stuart.summers@intel.com>
> Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
> Signed-off-by: Prasad Nallani <prasad.nallani@intel.com>
> ---
> drivers/gpu/drm/i915/gt/intel_sseu.c | 24 ++++++++++++++++++++----
> drivers/gpu/drm/i915/i915_getparam.c | 6 ++++--
> drivers/gpu/drm/i915/i915_reg.h | 3 +++
> 3 files changed, 27 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/gt/intel_sseu.c b/drivers/gpu/drm/i915/gt/intel_sseu.c
> index bbed8e8625e1..5d1b7d06c96b 100644
> --- a/drivers/gpu/drm/i915/gt/intel_sseu.c
> +++ b/drivers/gpu/drm/i915/gt/intel_sseu.c
> @@ -139,17 +139,33 @@ static void gen12_sseu_info_init(struct intel_gt *gt)
> * Gen12 has Dual-Subslices, which behave similarly to 2 gen11 SS.
> * Instead of splitting these, provide userspace with an array
> * of DSS to more closely represent the hardware resource.
> + *
> + * In addition, the concept of slice has been removed in Xe_HP.
> + * To be compatible with prior generations, assume a single slice
> + * across the entire device. Then calculate out the DSS for each
> + * workload type within that software slice.
> */
> intel_sseu_set_info(sseu, 1, 6, 16);
>
> - s_en = intel_uncore_read(uncore, GEN11_GT_SLICE_ENABLE) &
> - GEN11_GT_S_ENA_MASK;
> + /*
> + * As mentioned above, Xe_HP does not have the concept of a slice.
> + * Enable one for software backwards compatibility.
> + */
> + if (GRAPHICS_VER_FULL(gt->i915) >= IP_VER(12, 50))
> + s_en = 0x1;
> + else
> + s_en = intel_uncore_read(uncore, GEN11_GT_SLICE_ENABLE) &
> + GEN11_GT_S_ENA_MASK;
>
> dss_en = intel_uncore_read(uncore, GEN12_GT_DSS_ENABLE);
>
> /* one bit per pair of EUs */
> - eu_en_fuse = ~(intel_uncore_read(uncore, GEN11_EU_DISABLE) &
> - GEN11_EU_DIS_MASK);
> + if (GRAPHICS_VER_FULL(gt->i915) >= IP_VER(12, 50))
> + eu_en_fuse = intel_uncore_read(uncore, XEHP_EU_ENABLE) & XEHP_EU_ENA_MASK;
> + else
> + eu_en_fuse = ~(intel_uncore_read(uncore, GEN11_EU_DISABLE) &
> + GEN11_EU_DIS_MASK);
> +
> for (eu = 0; eu < sseu->max_eus_per_subslice / 2; eu++)
> if (eu_en_fuse & BIT(eu))
> eu_en |= BIT(eu * 2) | BIT(eu * 2 + 1);
> diff --git a/drivers/gpu/drm/i915/i915_getparam.c b/drivers/gpu/drm/i915/i915_getparam.c
> index 24e18219eb50..e289397d9178 100644
> --- a/drivers/gpu/drm/i915/i915_getparam.c
> +++ b/drivers/gpu/drm/i915/i915_getparam.c
> @@ -15,7 +15,7 @@ int i915_getparam_ioctl(struct drm_device *dev, void *data,
> struct pci_dev *pdev = to_pci_dev(dev->dev);
> const struct sseu_dev_info *sseu = &i915->gt.info.sseu;
> drm_i915_getparam_t *param = data;
> - int value;
> + int value = 0;
>
> switch (param->param) {
> case I915_PARAM_IRQ_ACTIVE:
> @@ -150,7 +150,9 @@ int i915_getparam_ioctl(struct drm_device *dev, void *data,
> return -ENODEV;
> break;
> case I915_PARAM_SUBSLICE_MASK:
> - value = sseu->subslice_mask[0];
> + /* Only copy bits from the first slice */
> + memcpy(&value, sseu->subslice_mask,
> + min(sseu->ss_stride, (u8)sizeof(value)));
> if (!value)
> return -ENODEV;
> break;
> diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
> index 62af453c8c54..99858bc593f0 100644
> --- a/drivers/gpu/drm/i915/i915_reg.h
> +++ b/drivers/gpu/drm/i915/i915_reg.h
> @@ -3225,6 +3225,9 @@ static inline bool i915_mmio_reg_valid(i915_reg_t reg)
>
> #define GEN12_GT_DSS_ENABLE _MMIO(0x913C)
>
> +#define XEHP_EU_ENABLE _MMIO(0x9134)
> +#define XEHP_EU_ENA_MASK 0xFF
> +
> #define GEN6_BSD_SLEEP_PSMI_CONTROL _MMIO(0x12050)
> #define GEN6_BSD_SLEEP_MSG_DISABLE (1 << 0)
> #define GEN6_BSD_SLEEP_FLUSH_DISABLE (1 << 2)