[PATCH 08/18] drm/i915: Drop runtime-pm assert from vgpu io accessors

Chris Wilson chris at chris-wilson.co.uk
Sat Aug 15 11:17:12 UTC 2020


The "mmio" writes into vgpu registers are simple memory traps from the
guest into the host. We do not need to assert in the guest that the
device is awake for the io as we do not write to the device itself.

However, over time we have refactored all the mmio accessors with the
result that the vgpu reuses the gen2 accessors and so inherits the
assert for runtime-pm of the native device. The assert though has
actually been there since commit 3be0bf5acca6 ("drm/i915: Create vGPU
specific MMIO operations to reduce traps").

References: 3be0bf5acca6 ("drm/i915: Create vGPU specific MMIO operations to reduce traps")
Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Yan Zhao <yan.y.zhao at intel.com>
Cc: Zhenyu Wang <zhenyuw at linux.intel.com>
Reviewed-by: Zhenyu Wang <zhenyuw at linux.intel.com>
---
 drivers/gpu/drm/i915/intel_uncore.c | 27 ++++++++++++++++++++++++++-
 1 file changed, 26 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/intel_uncore.c b/drivers/gpu/drm/i915/intel_uncore.c
index f5edee17902a..6d3310794d0f 100644
--- a/drivers/gpu/drm/i915/intel_uncore.c
+++ b/drivers/gpu/drm/i915/intel_uncore.c
@@ -1209,6 +1209,18 @@ unclaimed_reg_debug(struct intel_uncore *uncore,
 		spin_unlock(&uncore->debug->lock);
 }
 
+#define __vgpu_read(x) \
+static u##x \
+vgpu_read##x(struct intel_uncore *uncore, i915_reg_t reg, bool trace) { \
+	u##x val = __raw_uncore_read##x(uncore, reg); \
+	trace_i915_reg_rw(false, reg, val, sizeof(val), trace); \
+	return val; \
+}
+__vgpu_read(8)
+__vgpu_read(16)
+__vgpu_read(32)
+__vgpu_read(64)
+
 #define GEN2_READ_HEADER(x) \
 	u##x val = 0; \
 	assert_rpm_wakelock_held(uncore->rpm);
@@ -1414,6 +1426,16 @@ __gen_reg_write_funcs(gen8);
 #undef GEN6_WRITE_FOOTER
 #undef GEN6_WRITE_HEADER
 
+#define __vgpu_write(x) \
+static void \
+vgpu_write##x(struct intel_uncore *uncore, i915_reg_t reg, u##x val, bool trace) { \
+	trace_i915_reg_rw(true, reg, val, sizeof(val), trace); \
+	__raw_uncore_write##x(uncore, reg, val); \
+}
+__vgpu_write(8)
+__vgpu_write(16)
+__vgpu_write(32)
+
 #define ASSIGN_RAW_WRITE_MMIO_VFUNCS(uncore, x) \
 do { \
 	(uncore)->funcs.mmio_writeb = x##_write8; \
@@ -1735,7 +1757,10 @@ static void uncore_raw_init(struct intel_uncore *uncore)
 {
 	GEM_BUG_ON(intel_uncore_has_forcewake(uncore));
 
-	if (IS_GEN(uncore->i915, 5)) {
+	if (intel_vgpu_active(uncore->i915)) {
+		ASSIGN_RAW_WRITE_MMIO_VFUNCS(uncore, vgpu);
+		ASSIGN_RAW_READ_MMIO_VFUNCS(uncore, vgpu);
+	} else if (IS_GEN(uncore->i915, 5)) {
 		ASSIGN_RAW_WRITE_MMIO_VFUNCS(uncore, gen5);
 		ASSIGN_RAW_READ_MMIO_VFUNCS(uncore, gen5);
 	} else {
-- 
2.20.1



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