>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." This workaround seems a bit questionable as written since using all 1's to the RT_BASE register implies setting bit 0, which is a flag to indicate whether the address is valid. Indeed, we start seeing CI failures when we follow the directions here literally. Let's slightly deviate from the workaround instructions and set all bits _except_ for bit 0 of FBC_RT_BASE_ADDR_REGISTER. v2: - Mask off the RT_VALID bit. Experimentation with CI trybot indicates that this is necessary to avoid reset failures on BCS. Bspec: 11388 Bspec: 33451 Cc: José Roberto de Souza <jose.souza@xxxxxxxxx> Cc: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> Signed-off-by: Matt Roper <matthew.d.roper@xxxxxxxxx> --- drivers/gpu/drm/i915/gt/intel_workarounds.c | 6 ++++++ drivers/gpu/drm/i915/i915_reg.h | 1 + 2 files changed, 7 insertions(+) diff --git a/drivers/gpu/drm/i915/gt/intel_workarounds.c b/drivers/gpu/drm/i915/gt/intel_workarounds.c index 704ace01e7f5..f70b7a95bc23 100644 --- a/drivers/gpu/drm/i915/gt/intel_workarounds.c +++ b/drivers/gpu/drm/i915/gt/intel_workarounds.c @@ -567,6 +567,12 @@ 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 */ + wa_write_masked_or(wal, IVB_FBC_RT_BASE_UPPER, + 0, /* write-only register; skip validation */ + 0xFFFFFFFF); + wa_write(wal, IVB_FBC_RT_BASE, 0xFFFFFFFF & ~ILK_FBC_RT_VALID); } static void diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index ea2f0fa2402d..bce7326329db 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -3170,6 +3170,7 @@ static inline bool i915_mmio_reg_valid(i915_reg_t reg) /* 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 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx