Re: [PATCH v2 5/6] drm/i915/uncore: Drop gen11 mmio read handlers

[Lucas De Marchi <lucas.demarchi@xxxxxxxxx>]

On Fri, Sep 10, 2021 at 01:10:29PM -0700, Matt Roper wrote:
> Consolidate down to just a single 'fwtable' implementation.  For reads
> we don't need to worry about shadow tables.  Also, the
> NEEDS_FORCE_WAKE() check we previously had in the fwtable implementation
> can be dropped --- if a register is outside that range on one of the old
> platforms, then it won't belong to any forcewake range and 0 will be
> returned anyway.
>
> v2:
> - Restore NEEDS_FORCE_WAKE() check.  (Chris, Tvrtko)
>
> Cc: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
> Cc: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxxxxxxxx>
> Signed-off-by: Matt Roper <matthew.d.roper@xxxxxxxxx>
> ---
> drivers/gpu/drm/i915/intel_uncore.c | 40 ++++++++++++-----------------
> 1 file changed, 17 insertions(+), 23 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_uncore.c b/drivers/gpu/drm/i915/intel_uncore.c
> index bfb2a6337f9d..10f124297e7c 100644
> --- a/drivers/gpu/drm/i915/intel_uncore.c
> +++ b/drivers/gpu/drm/i915/intel_uncore.c
> @@ -935,9 +935,6 @@ static const struct intel_forcewake_range __vlv_fw_ranges[] = {
> 	__fwd; \
> })
>
> -#define __gen11_fwtable_reg_read_fw_domains(uncore, offset) \
> -	find_fw_domain(uncore, offset)
> -
> /* *Must* be sorted by offset! See intel_shadow_table_check(). */
> static const struct i915_range gen8_shadowed_regs[] = {
> 	{ .start =  0x2030, .end =  0x2030 },
> @@ -1570,33 +1567,30 @@ static inline void __force_wake_auto(struct intel_uncore *uncore,
> 		___force_wake_auto(uncore, fw_domains);
> }
>
> -#define __gen_read(func, x) \
> +#define __gen_fwtable_read(x) \
> static u##x \
> -func##_read##x(struct intel_uncore *uncore, i915_reg_t reg, bool trace) { \
> +fwtable_read##x(struct intel_uncore *uncore, i915_reg_t reg, bool trace) \
> +{ \
> 	enum forcewake_domains fw_engine; \
> 	GEN6_READ_HEADER(x); \
> -	fw_engine = __##func##_reg_read_fw_domains(uncore, offset); \
> +	fw_engine = __fwtable_reg_read_fw_domains(uncore, offset); \
> 	if (fw_engine) \
> 		__force_wake_auto(uncore, fw_engine); \
> 	val = __raw_uncore_read##x(uncore, reg); \
> 	GEN6_READ_FOOTER; \
> }
>
> -#define __gen_reg_read_funcs(func) \
> -static enum forcewake_domains \
> -func##_reg_read_fw_domains(struct intel_uncore *uncore, i915_reg_t reg) { \
> -	return __##func##_reg_read_fw_domains(uncore, i915_mmio_reg_offset(reg)); \
> -} \
> -\
> -__gen_read(func, 8) \
> -__gen_read(func, 16) \
> -__gen_read(func, 32) \
> -__gen_read(func, 64)
> +static enum forcewake_domains
> +fwtable_reg_read_fw_domains(struct intel_uncore *uncore, i915_reg_t reg) {
> +	return __fwtable_reg_read_fw_domains(uncore, i915_mmio_reg_offset(reg));
> +}
>
> -__gen_reg_read_funcs(gen11_fwtable);
> -__gen_reg_read_funcs(fwtable);
> +__gen_fwtable_read(8)
> +__gen_fwtable_read(16)
> +__gen_fwtable_read(32)
> +__gen_fwtable_read(64)
>
> -#undef __gen_reg_read_funcs
> +#undef __gen_fwtable_read
> #undef GEN6_READ_FOOTER
> #undef GEN6_READ_HEADER
>
> @@ -2062,22 +2056,22 @@ static int uncore_forcewake_init(struct intel_uncore *uncore)
> 		ASSIGN_FW_DOMAINS_TABLE(uncore, __dg2_fw_ranges);
> 		ASSIGN_SHADOW_TABLE(uncore, gen12_shadowed_regs);
> 		ASSIGN_WRITE_MMIO_VFUNCS(uncore, fwtable);
> -		ASSIGN_READ_MMIO_VFUNCS(uncore, gen11_fwtable);
> +		ASSIGN_READ_MMIO_VFUNCS(uncore, fwtable);
> 	} else if (GRAPHICS_VER_FULL(i915) >= IP_VER(12, 50)) {
> 		ASSIGN_FW_DOMAINS_TABLE(uncore, __xehp_fw_ranges);
> 		ASSIGN_SHADOW_TABLE(uncore, gen12_shadowed_regs);
> 		ASSIGN_WRITE_MMIO_VFUNCS(uncore, fwtable);
> -		ASSIGN_READ_MMIO_VFUNCS(uncore, gen11_fwtable);
> +		ASSIGN_READ_MMIO_VFUNCS(uncore, fwtable);
> 	} else if (GRAPHICS_VER(i915) >= 12) {
> 		ASSIGN_FW_DOMAINS_TABLE(uncore, __gen12_fw_ranges);
> 		ASSIGN_SHADOW_TABLE(uncore, gen12_shadowed_regs);
> 		ASSIGN_WRITE_MMIO_VFUNCS(uncore, fwtable);
> -		ASSIGN_READ_MMIO_VFUNCS(uncore, gen11_fwtable);
> +		ASSIGN_READ_MMIO_VFUNCS(uncore, fwtable);
> 	} else if (GRAPHICS_VER(i915) == 11) {
> 		ASSIGN_FW_DOMAINS_TABLE(uncore, __gen11_fw_ranges);
> 		ASSIGN_SHADOW_TABLE(uncore, gen11_shadowed_regs);
> 		ASSIGN_WRITE_MMIO_VFUNCS(uncore, fwtable);
> -		ASSIGN_READ_MMIO_VFUNCS(uncore, gen11_fwtable);
> +		ASSIGN_READ_MMIO_VFUNCS(uncore, fwtable);

these together with patch 1 make the fwtable variant be the only one
used for reads.... so, should we pull these assignments out of if/else
chain? gen < 6 don't have forcewake so afaics we cover all the
platforms.

this can be done as a separate patch though.


Reviewed-by: Lucas De Marchi <lucas.demarchi@xxxxxxxxx>

Lucas De Marchi

> 	} else if (IS_GRAPHICS_VER(i915, 9, 10)) {
> 		ASSIGN_FW_DOMAINS_TABLE(uncore, __gen9_fw_ranges);
> 		ASSIGN_SHADOW_TABLE(uncore, gen8_shadowed_regs);
> --
> 2.25.4