drm/i915/execlists: Pull the w/a LRI emission into a helper

Having the w/a registers as an open-coded table leaves a trap for the
unwary; it would be easy to miss incrementing the LRI counter when
adding a new register to the list. Instead, pull the list of registers
into a table, so that we only need add new registers to that table
rather than try and remember important side-effects of earlier chunks of
GPU instructions.

Suggested-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180618094150.30895-1-chris@chris-wilson.co.uk

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 54ec7ab..1f928ba 100644 (file)
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -156,6 +156,7 @@ static inline bool i915_mmio_reg_valid(i915_reg_t reg)
 #define _PHY3(phy, ...) _PICK(phy, __VA_ARGS__)
 #define _MMIO_PHY3(phy, a, b, c) _MMIO(_PHY3(phy, a, b, c))
 
+#define __MASKED_FIELD(mask, value) ((mask) << 16 | (value))
 #define _MASKED_FIELD(mask, value) ({                                     \
        if (__builtin_constant_p(mask))                                    \
                BUILD_BUG_ON_MSG(((mask) & 0xffff0000), "Incorrect mask"); \
@@ -164,7 +165,7 @@ static inline bool i915_mmio_reg_valid(i915_reg_t reg)
        if (__builtin_constant_p(mask) && __builtin_constant_p(value))     \
                BUILD_BUG_ON_MSG((value) & ~(mask),                        \
                                 "Incorrect value for mask");              \
-       (mask) << 16 | (value); })
+       __MASKED_FIELD(mask, value); })
 #define _MASKED_BIT_ENABLE(a)  ({ typeof(a) _a = (a); _MASKED_FIELD(_a, _a); })
 #define _MASKED_BIT_DISABLE(a) (_MASKED_FIELD((a), 0))
 

diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index b6c230b..10deebe 100644 (file)
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -1566,29 +1566,56 @@ static u32 *gen8_init_indirectctx_bb(struct intel_engine_cs *engine, u32 *batch)
        return batch;
 }
 
-static u32 *gen9_init_indirectctx_bb(struct intel_engine_cs *engine, u32 *batch)
+struct lri {
+       i915_reg_t reg;
+       u32 value;
+};
+
+static u32 *emit_lri(u32 *batch, const struct lri *lri, unsigned int count)
 {
-       *batch++ = MI_ARB_ON_OFF | MI_ARB_DISABLE;
+       GEM_BUG_ON(!count || count > 63);
 
-       /* WaFlushCoherentL3CacheLinesAtContextSwitch:skl,bxt,glk */
-       batch = gen8_emit_flush_coherentl3_wa(engine, batch);
+       *batch++ = MI_LOAD_REGISTER_IMM(count);
+       do {
+               *batch++ = i915_mmio_reg_offset(lri->reg);
+               *batch++ = lri->value;
+       } while (lri++, --count);
+       *batch++ = MI_NOOP;
 
-       *batch++ = MI_LOAD_REGISTER_IMM(3);
+       return batch;
+}
 
-       /* WaDisableGatherAtSetShaderCommonSlice:skl,bxt,kbl,glk */
-       *batch++ = i915_mmio_reg_offset(COMMON_SLICE_CHICKEN2);
-       *batch++ = _MASKED_BIT_DISABLE(
-                       GEN9_DISABLE_GATHER_AT_SET_SHADER_COMMON_SLICE);
+static u32 *gen9_init_indirectctx_bb(struct intel_engine_cs *engine, u32 *batch)
+{
+       static const struct lri lri[] = {
+               /* WaDisableGatherAtSetShaderCommonSlice:skl,bxt,kbl,glk */
+               {
+                       COMMON_SLICE_CHICKEN2,
+                       __MASKED_FIELD(GEN9_DISABLE_GATHER_AT_SET_SHADER_COMMON_SLICE,
+                                      0),
+               },
+
+               /* BSpec: 11391 */
+               {
+                       FF_SLICE_CHICKEN,
+                       __MASKED_FIELD(FF_SLICE_CHICKEN_CL_PROVOKING_VERTEX_FIX,
+                                      FF_SLICE_CHICKEN_CL_PROVOKING_VERTEX_FIX),
+               },
+
+               /* BSpec: 11299 */
+               {
+                       _3D_CHICKEN3,
+                       __MASKED_FIELD(_3D_CHICKEN_SF_PROVOKING_VERTEX_FIX,
+                                      _3D_CHICKEN_SF_PROVOKING_VERTEX_FIX),
+               }
+       };
 
-       /* BSpec: 11391 */
-       *batch++ = i915_mmio_reg_offset(FF_SLICE_CHICKEN);
-       *batch++ = _MASKED_BIT_ENABLE(FF_SLICE_CHICKEN_CL_PROVOKING_VERTEX_FIX);
+       *batch++ = MI_ARB_ON_OFF | MI_ARB_DISABLE;
 
-       /* BSpec: 11299 */
-       *batch++ = i915_mmio_reg_offset(_3D_CHICKEN3);
-       *batch++ = _MASKED_BIT_ENABLE(_3D_CHICKEN_SF_PROVOKING_VERTEX_FIX);
+       /* WaFlushCoherentL3CacheLinesAtContextSwitch:skl,bxt,glk */
+       batch = gen8_emit_flush_coherentl3_wa(engine, batch);
 
-       *batch++ = MI_NOOP;
+       batch = emit_lri(batch, lri, ARRAY_SIZE(lri));
 
        /* WaClearSlmSpaceAtContextSwitch:kbl */
        /* Actual scratch location is at 128 bytes offset */