From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> hsw/bdw lack the pipe register vs. display register distinction in their PSR masking capabilities. So to keep our CURSURFLIVE tricks working we need to just unmask all display register writes on these platforms. The downside being that any display regitster (eg. even SWF regs) will cause a PSR exit. Note that WaMaskMMIOWriteForPSR asks us to mask this on bdw, but that won't work since we need those CURSURFLIVE tricks. Observations on actual hardware show that this causes one extra PSR exit ~every 10 seconds, which is pretty much irrelevant. I suspect this is due to the pcode poking at IPS_CTL. Disabling IPS does not stop it however, so either I'm wrong or pcode pokes at the register regardless of whether it's actually trying to enable/disable IPS. Also when the machine is busy (eg. just running 'find /') these extra PSR exits cease, which again points at pcode or some other PM entity as being the culprit. Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> --- drivers/gpu/drm/i915/display/intel_psr.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/display/intel_psr.c b/drivers/gpu/drm/i915/display/intel_psr.c index 67de5c7267b9..92369f95ee88 100644 --- a/drivers/gpu/drm/i915/display/intel_psr.c +++ b/drivers/gpu/drm/i915/display/intel_psr.c @@ -1393,7 +1393,11 @@ static void intel_psr_enable_source(struct intel_dp *intel_dp, EDP_PSR_DEBUG_MASK_LPSP | EDP_PSR_DEBUG_MASK_MAX_SLEEP; - if (DISPLAY_VER(dev_priv) < 11) + /* + * No separate pipe reg write mask on hsw/bdw, so have to unmask all + * registers in order to keep the CURSURFLIVE tricks working :( + */ + if (IS_DISPLAY_VER(dev_priv, 9, 10)) mask |= EDP_PSR_DEBUG_MASK_DISP_REG_WRITE; intel_de_write(dev_priv, psr_debug_reg(dev_priv, cpu_transcoder), mask); -- 2.39.3
