[PATCH] drm/i915/gen11: Add Wa_1604278689:icl,ehl [NO UPPER REG]

[Matt Roper]

>From the bspec:

        "SW must always program the FBC_RT_BASE_ADDR_REGISTER_* register
        in Render Engine to a reserved value (0xFFFF_FFFF) such that the
        programmed value doesn’t match the render target surface address
        programmed. This would disable render engine from generating
        modify messages to FBC unit in display."

Bspec: 11388
Bspec: 33451
Signed-off-by: Matt Roper <matthew.d.roper at intel.com>
---
 drivers/gpu/drm/i915/gt/intel_workarounds.c | 8 ++++++++
 drivers/gpu/drm/i915/i915_reg.h             | 1 +
 2 files changed, 9 insertions(+)

diff --git a/drivers/gpu/drm/i915/gt/intel_workarounds.c b/drivers/gpu/drm/i915/gt/intel_workarounds.c
index 704ace01e7f5..2caac979e534 100644
--- a/drivers/gpu/drm/i915/gt/intel_workarounds.c
+++ b/drivers/gpu/drm/i915/gt/intel_workarounds.c
@@ -567,6 +567,14 @@ static void icl_ctx_workarounds_init(struct intel_engine_cs *engine,
 	/* allow headerless messages for preemptible GPGPU context */
 	WA_SET_BIT_MASKED(GEN10_SAMPLER_MODE,
 			  GEN11_SAMPLER_ENABLE_HEADLESS_MSG);
+
+	/* Wa_1604278689:icl,ehl */
+#if 0
+	wa_write_masked_or(wal, IVB_FBC_RT_BASE_UPPER,
+			   0, /* write-only register; skip validation */
+			   0xFFFFFFFF);
+#endif
+	wa_write(wal, IVB_FBC_RT_BASE, 0xFFFFFFFF);
 }
 
 static void
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index def6dbdc7e2e..14af1b1dc0d3 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -3214,6 +3214,7 @@ enum i915_power_well_id {
 
 /* Framebuffer compression for Ivybridge */
 #define IVB_FBC_RT_BASE			_MMIO(0x7020)
+#define IVB_FBC_RT_BASE_UPPER		_MMIO(0x7024)
 
 #define IPS_CTL		_MMIO(0x43408)
 #define   IPS_ENABLE	(1 << 31)
-- 
2.20.1