>-----Original Message----- >From: Ben Widawsky [mailto:benjamin.widawsky@xxxxxxxxxxxxxxx] >Sent: Thursday, April 10, 2014 11:41 AM >To: Chris Wilson; Widawsky, Benjamin; Intel GFX; Runyan, Arthur J >Subject: Re: [PATCH] drm/i915/bdw: Add 42ms delay for IPS disable > >On Thu, Apr 10, 2014 at 07:12:46PM +0100, Chris Wilson wrote: >> On Thu, Apr 10, 2014 at 11:04:17AM -0700, Ben Widawsky wrote: >> > From: Ben Widawsky <benjamin.widawsky@xxxxxxxxxxxxxxx> >> > >> > This is a requirement added to the spec. This patch will present >> > persistent corruption on the display. > >s/present/prevent > >> >> Prevent? I don't think we want to start showing corruption to the user. >> >> > Cc: Art Runyan <arthur.j.runyan@xxxxxxxxx> >> > Signed-off-by: Ben Widawsky <ben@xxxxxxxxxxxx> >> > --- >> > drivers/gpu/drm/i915/intel_display.c | 6 +++++- >> > 1 file changed, 5 insertions(+), 1 deletion(-) >> > >> > diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c >> > index 7f02444..ebc84ee 100644 >> > --- a/drivers/gpu/drm/i915/intel_display.c >> > +++ b/drivers/gpu/drm/i915/intel_display.c >> > @@ -3583,7 +3583,7 @@ void hsw_disable_ips(struct intel_crtc *crtc) >> > return; >> > >> > assert_plane_enabled(dev_priv, crtc->plane); >> > - if (IS_BROADWELL(crtc->base.dev)) { >> > + if (IS_BROADWELL(dev)) { >> > mutex_lock(&dev_priv->rps.hw_lock); >> > WARN_ON(sandybridge_pcode_write(dev_priv, DISPLAY_IPS_CONTROL, >0)); >> > mutex_unlock(&dev_priv->rps.hw_lock); >> > @@ -3594,6 +3594,10 @@ void hsw_disable_ips(struct intel_crtc *crtc) >> > >> > /* We need to wait for a vblank before we can disable the plane. */ >> > intel_wait_for_vblank(dev, crtc->pipe); >> > + >> > + /* wait for pcode to finish disabling IPS, which may take up to 42ms */ >> > + if (IS_BROADWELL(dev)) >> > + msleep(42); The added delay for broadwell should come before the wait for vblank. Also, you should check for IPS_CTL bit 31 (Enable IPS) to become 0, just in case the 42ms was a lie, or something got stuck. >> >> Reading too much Douglas Adams? >> -Chris >> > >It's those damn display arTchitects Hah.... I am an Art, but not one of those lofty architects. > >-- >Ben Widawsky, Intel Open Source Technology Center _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
