On Tue, Oct 27, 2015 at 08:41:31PM +0200, Imre Deak wrote: > On pe, 2015-10-23 at 11:41 +0200, Patrik Jakobsson wrote: > > The current CSR loading code depends on the CSR program memory to be > > cleared after boot. This is unfortunately not true on all hardware. > > Instead make use of the FW_UNINITIALIZED state in init and check for > > FW_LOADED to prevent init path from skipping the actual programming. > > > > v2: Move initialization of state to after HAS_CSR() check > > > > Signed-off-by: Patrik Jakobsson <patrik.jakobsson@xxxxxxxxxxxxxxx> > > Tested-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> > > Reviewed-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> > > --- > > drivers/gpu/drm/i915/intel_csr.c | 4 +++- > > 1 file changed, 3 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/gpu/drm/i915/intel_csr.c b/drivers/gpu/drm/i915/intel_csr.c > > index 9e530a7..e74c09e 100644 > > --- a/drivers/gpu/drm/i915/intel_csr.c > > +++ b/drivers/gpu/drm/i915/intel_csr.c > > @@ -271,7 +271,7 @@ void intel_csr_load_program(struct drm_device *dev) > > * Unfortunately the ACPI subsystem doesn't yet give us a way to > > * differentiate this, hence figure it out with this hack. > > */ > > - if (I915_READ(CSR_PROGRAM(0))) > > + if (I915_READ(CSR_PROGRAM(0)) && dev_priv->csr.state == FW_LOADED) > > return; > > As Animesh said csr->state is being removed, so I'd prefer if we didn't > add new users for it. > > I think the proper solution for this would be to reprogram the firmware > only when we know we have to and not have here either of the above > checks. The points we need to reprogram the firmware: > > S3/S4 both on SKL. > S3/S4/DC9 (runtime suspend) on BXT. Isn't this what csr->state was intended to solve in the first place? It's very easy to get lost in the discussions around DMC so I've might have missed something. > > To fix this particular bug you could also just add an > intel_csr_reprogram() that would check for CSR_PROGRAM(0) as now, while > during driver loading you would program the firmware unconditionally. Did some more digging and it seems the CSR program is not cleared on warm boot. So checking CSR_PROGRAM(0) == payload[0] will not work. Don't think we can figure out the CSR status by probing hardware so we must keep a flag for this somewhere. The CSR program loading is async so the state need to be stored somewhere and not just passed along as a function argument. -Patrik > > --Imre > > > > > > mutex_lock(&dev_priv->csr_lock); > > @@ -428,6 +428,8 @@ void intel_csr_ucode_init(struct drm_device *dev) > > if (!HAS_CSR(dev)) > > return; > > > > + intel_csr_load_status_set(dev_priv, FW_UNINITIALIZED); > > + > > if (IS_SKYLAKE(dev)) > > csr->fw_path = I915_CSR_SKL; > > else if (IS_BROXTON(dev_priv)) > > > _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
