[Intel-gfx] [PATCH] drm/i915: Restore DMC required version for Skylake (1.26)

[Vivi, Rodrigo]

On Wed, 2016-08-10 at 10:55 +0300, Jani Nikula wrote:
> On Wed, 10 Aug 2016, Rodrigo Vivi <rodrigo.vivi at intel.com> wrote:
> > 
> > With commit 4aa7fb9c ("drm/i915/dmc: Step away from symbolic
> > links") we started loading the firmware version directly
> > instead of symbolic links.
> > 
> > With this VERSION_REQUIRED variables changed the meaning
> > from minimal required to exact version required. Along
> > with this change we started using the latest stable
> > DMC firmware as the required one 1.26.
> > 
> > This patch is correct. However in some merge this
> > change got missed and it was overwritten by the old
> > version.
> > 
> > 1.23 is unstable and can cause blank screens so let's
> > avoid it.
> > 
> > Cc: stable at vger.kernel.org
> No. 4aa7fb9c is not in a stable released kernel. Please try 'dim
> fixes
> 4aa7fb9c'.
> 
> I guess 4aa7fb9c *not* having been released saves us from restoring
> 1.23
> to linux-firmware. However, v4.8-rc1 will still be busted if 1.23
> isn't
> restored to linux-firmware.

ok, I'm restoring per maintainers request, but I'm trying to warn that
it might be busted with 1.23 in place. Without it users will only have
warning and not the ideal power consumption.

> 
> BR,
> Jani.
> 
> 
> 
> > 
> > Cc: Jani Nikula <jani.nikula at intel.com>
> > Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
> > Cc: Patrik Jakobsson <patrik.jakobsson at linux.intel.com>
> > Cc: Matthew Atwood <matthew.s.atwood at intel.com>
> > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=97182
> > Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
> > ---
> >  drivers/gpu/drm/i915/intel_csr.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/intel_csr.c
> > b/drivers/gpu/drm/i915/intel_csr.c
> > index fb27d18..0efce3f 100644
> > --- a/drivers/gpu/drm/i915/intel_csr.c
> > +++ b/drivers/gpu/drm/i915/intel_csr.c
> > @@ -40,7 +40,7 @@ MODULE_FIRMWARE(I915_CSR_KBL);
> >  
> >  #define I915_CSR_SKL "i915/skl_dmc_ver1.bin"
> >  MODULE_FIRMWARE(I915_CSR_SKL);
> > -#define SKL_CSR_VERSION_REQUIRED	CSR_VERSION(1, 23)
> > +#define SKL_CSR_VERSION_REQUIRED	CSR_VERSION(1, 26)
> >  
> >  #define I915_CSR_BXT "i915/bxt_dmc_ver1.bin"
> >  MODULE_FIRMWARE(I915_CSR_BXT);