[Intel-gfx] [PATCH 2/9] drm/i915: add HAS_FORCEWAKE flag to uncore

[Michal Wajdeczko]

On Mon, 25 Mar 2019 22:49:33 +0100, Daniele Ceraolo Spurio  
<daniele.ceraolospurio at intel.com> wrote:

> We have several cases where we don't have forcewake (older gens, GVT and
> planned display-only uncore), so, instead of checking every time against
> the various condition, save the info in a flag and use that.
>
> Note that this patch also change the behavior for gen5 with vpgu
> enabled, but this is not an issue since we don't support vgpu on gen5.
>
> v2: split out from previous path, fix check for missing case (Paulo)
>
> Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
> Cc: Paulo Zanoni <paulo.r.zanoni at intel.com>
> Cc: Chris Wilson <chris at chris-wilson.co.uk>
> ---
>  drivers/gpu/drm/i915/intel_uncore.c | 31 +++++++++++++++++++----------
>  drivers/gpu/drm/i915/intel_uncore.h |  3 +++
>  2 files changed, 24 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_uncore.c  
> b/drivers/gpu/drm/i915/intel_uncore.c
> index 3f74889c4212..0259a61a745f 100644
> --- a/drivers/gpu/drm/i915/intel_uncore.c
> +++ b/drivers/gpu/drm/i915/intel_uncore.c
> @@ -1391,7 +1391,7 @@ static void intel_uncore_fw_domains_init(struct  
> intel_uncore *uncore)
>  {
>  	struct drm_i915_private *i915 = uncore_to_i915(uncore);
> -	if (INTEL_GEN(i915) <= 5 || intel_vgpu_active(i915))
> +	if (!(uncore->flags & UNCORE_HAS_FORCEWAKE))
>  		return;
> 	if (INTEL_GEN(i915) >= 11) {
> @@ -1590,6 +1590,9 @@ int intel_uncore_init(struct intel_uncore *uncore)
> 	i915_check_vgpu(i915);
> +	if (INTEL_GEN(i915) > 5 && !intel_vgpu_active(i915))
> +		uncore->flags |= UNCORE_HAS_FORCEWAKE;
> +
>  	intel_uncore_edram_detect(i915);
>  	intel_uncore_fw_domains_init(uncore);
>  	__intel_uncore_early_sanitize(uncore, 0);
> @@ -1598,12 +1601,14 @@ int intel_uncore_init(struct intel_uncore  
> *uncore)
>  	uncore->pmic_bus_access_nb.notifier_call =
>  		i915_pmic_bus_access_notifier;
> -	if (IS_GEN_RANGE(i915, 2, 4) || intel_vgpu_active(i915)) {
> -		ASSIGN_WRITE_MMIO_VFUNCS(uncore, gen2);
> -		ASSIGN_READ_MMIO_VFUNCS(uncore, gen2);
> -	} else if (IS_GEN(i915, 5)) {
> -		ASSIGN_WRITE_MMIO_VFUNCS(uncore, gen5);
> -		ASSIGN_READ_MMIO_VFUNCS(uncore, gen5);
> +	if (!(uncore->flags & UNCORE_HAS_FORCEWAKE)) {
> +		if (IS_GEN(i915, 5)) {
> +			ASSIGN_WRITE_MMIO_VFUNCS(uncore, gen5);
> +			ASSIGN_READ_MMIO_VFUNCS(uncore, gen5);
> +		} else {
> +			ASSIGN_WRITE_MMIO_VFUNCS(uncore, gen2);
> +			ASSIGN_READ_MMIO_VFUNCS(uncore, gen2);
> +		}
>  	} else if (IS_GEN_RANGE(i915, 6, 7)) {
>  		ASSIGN_WRITE_MMIO_VFUNCS(uncore, gen6);
> @@ -1912,7 +1917,10 @@ intel_uncore_forcewake_for_read(struct  
> drm_i915_private *dev_priv,
>  	} else if (INTEL_GEN(dev_priv) >= 6) {
>  		fw_domains = __gen6_reg_read_fw_domains(uncore, offset);
>  	} else {
> -		WARN_ON(!IS_GEN_RANGE(dev_priv, 2, 5));
> +		/* on devices with FW we expect to hit one of the above cases */
> +		if (unlikely(uncore->flags & UNCORE_HAS_FORCEWAKE))
> +			MISSING_CASE(INTEL_GEN(dev_priv));
> +
>  		fw_domains = 0;
>  	}
> @@ -1938,7 +1946,10 @@ intel_uncore_forcewake_for_write(struct  
> drm_i915_private *dev_priv,
>  	} else if (IS_GEN_RANGE(dev_priv, 6, 7)) {
>  		fw_domains = FORCEWAKE_RENDER;
>  	} else {
> -		WARN_ON(!IS_GEN_RANGE(dev_priv, 2, 5));
> +		/* on devices with FW we expect to hit one of the above cases */
> +		if (unlikely(uncore->flags & UNCORE_HAS_FORCEWAKE))
> +			MISSING_CASE(INTEL_GEN(dev_priv));
> +
>  		fw_domains = 0;
>  	}
> @@ -1969,7 +1980,7 @@ intel_uncore_forcewake_for_reg(struct  
> drm_i915_private *dev_priv,
> 	WARN_ON(!op);
> -	if (intel_vgpu_active(dev_priv))
> +	if (!(dev_priv->uncore.flags & UNCORE_HAS_FORCEWAKE))

nit: as this condition is used in few places, maybe we can add nice helper:

static inline bool intel_uncore_has_forcewake(struct intel_uncore *uncore)
{
	return uncore->flags & UNCORE_HAS_FORCEWAKE;
}

Michal

>  		return 0;
> 	if (op & FW_REG_READ)
> diff --git a/drivers/gpu/drm/i915/intel_uncore.h  
> b/drivers/gpu/drm/i915/intel_uncore.h
> index f7670cbc41c9..4947542c6ea7 100644
> --- a/drivers/gpu/drm/i915/intel_uncore.h
> +++ b/drivers/gpu/drm/i915/intel_uncore.h
> @@ -127,6 +127,9 @@ struct intel_uncore {
>  	} user_forcewake;
> 	int unclaimed_mmio_check;
> +
> +	u32 flags;
> +#define UNCORE_HAS_FORCEWAKE		BIT(0)
>  };
> /* Iterate over initialised fw domains */