[Intel-gfx] [PATCH 1/2] drm/i915: Remove nonpriv flags when srm/lrm

[Mika Kuoppala]

On testing the whitelists, using any of the nonpriv
flags when trying to access the register offset will lead
to failure.

Define address mask to get the mmio offset in order
to guard against any current and future flag usage.

Cc: Tapani Pälli <tapani.palli at intel.com>
Cc: Chris Wilson <chris at chris-wilson.co.uk>
Signed-off-by: Mika Kuoppala <mika.kuoppala at linux.intel.com>
---
 drivers/gpu/drm/i915/gt/selftest_workarounds.c | 7 +++++--
 drivers/gpu/drm/i915/i915_reg.h                | 1 +
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/selftest_workarounds.c b/drivers/gpu/drm/i915/gt/selftest_workarounds.c
index ef02920cec29..54324c6577dc 100644
--- a/drivers/gpu/drm/i915/gt/selftest_workarounds.c
+++ b/drivers/gpu/drm/i915/gt/selftest_workarounds.c
@@ -513,6 +513,9 @@ static int check_dirty_whitelist(struct i915_gem_context *ctx,
 
 		ro_reg = ro_register(reg);
 
+		/* Clear non priv flags */
+		reg &= RING_FORCE_TO_NONPRIV_ADDRESS_MASK;
+
 		srm = MI_STORE_REGISTER_MEM;
 		lrm = MI_LOAD_REGISTER_MEM;
 		if (INTEL_GEN(ctx->i915) >= 8)
@@ -810,8 +813,8 @@ static int read_whitelisted_registers(struct i915_gem_context *ctx,
 		u64 offset = results->node.start + sizeof(u32) * i;
 		u32 reg = i915_mmio_reg_offset(engine->whitelist.list[i].reg);
 
-		/* Clear access permission field */
-		reg &= ~RING_FORCE_TO_NONPRIV_ACCESS_MASK;
+		/* Clear non priv flags */
+		reg &= RING_FORCE_TO_NONPRIV_ADDRESS_MASK;
 
 		*cs++ = srm;
 		*cs++ = reg;
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 855db888516c..3ba503b5e0d9 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -2490,6 +2490,7 @@ static inline bool i915_mmio_reg_valid(i915_reg_t reg)
 #define GEN8_RING_CS_GPR_UDW(base, n)	_MMIO((base) + 0x600 + (n) * 8 + 4)
 
 #define RING_FORCE_TO_NONPRIV(base, i) _MMIO(((base) + 0x4D0) + (i) * 4)
+#define   RING_FORCE_TO_NONPRIV_ADDRESS_MASK	REG_GENMASK(25, 2)
 #define   RING_FORCE_TO_NONPRIV_ACCESS_RW	(0 << 28)    /* CFL+ & Gen11+ */
 #define   RING_FORCE_TO_NONPRIV_ACCESS_RD	(1 << 28)
 #define   RING_FORCE_TO_NONPRIV_ACCESS_WR	(2 << 28)
-- 
2.17.1