[Intel-gfx] [PATCH] drm/i915/dmc: Accept symbolic link in firmware name

[Imre Deak]

On to, 2016-07-07 at 17:57 +0300, Mika Kuoppala wrote:
> "Vivi, Rodrigo" <rodrigo.vivi at intel.com> writes:
> 
> > Nak.
> > 
> > I don't intend to update the symbolic links on linux-firmware.git
> > repository anymore so if we receive a new minor version update we
> > are
> > not going to load.
> > 
> > I was the one advocating in the favor for the symbolic link
> > flexibility
> > but I lost the discussions for the stability and validation etc.
> > 
> 
> And I was one advocating in favor of getting rid of symlink. But the
> filename versioning is superfluous as the contents has the version
> info
> which we can solely rely to not run something we dont want.
> 
> So I am not sure what we lose in stability and validation front
> with the strict version check.

Bisection is more cumbersome with a symlink.

--Imre

> -Mika
> 
> > So let's just move away from symbolic link for good.
> > 
> > 
> > On Tue, 2016-07-05 at 12:25 +0300, Mika Kuoppala wrote:
> > > We need the ability to explicitly load only a specified firmware
> > > version. As the firmware blob contains the version, we use
> > > that to filter out the ones we don't want. The version encoded
> > > into the firmware name is superfluous and we should allow user
> > > to point into specific firmware through a symlink, and only do
> > > filtering based on the version stamp included in the blob.
> > > This allows user to conveniently point to a firmware blob and
> > > still gives us the control of what we decided to run on.
> > > 
> > > This is partial revert of
> > > 4aa7fb9c3c4f ("drm/i915/dmc: Step away from symbolic links")
> > > 
> > > Fixes: 4aa7fb9c3c4f ("drm/i915/dmc: Step away from symbolic
> > > links")
> > > References: https://bugs.freedesktop.org/show_bug.cgi?id=96800
> > > Reported-by: Mike Lothian <mike at fireburn.co.uk>
> > > Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
> > > Cc: Imre Deak <imre.deak at intel.com>
> > > Cc: Mika Kuoppala <mika.kuoppala at linux.intel.com>
> > > Cc: Patrik Jakobsson <patrik.jakobsson at linux.intel.com>
> > > Cc: Chris Wilson <chris at chris-wilson.co.uk>
> > > Signed-off-by: Mika Kuoppala <mika.kuoppala at intel.com>
> > > ---
> > >  drivers/gpu/drm/i915/intel_csr.c | 6 +++---
> > >  1 file changed, 3 insertions(+), 3 deletions(-)
> > > 
> > > diff --git a/drivers/gpu/drm/i915/intel_csr.c
> > > b/drivers/gpu/drm/i915/intel_csr.c
> > > index ea047cd46b71..77d01a0b64b4 100644
> > > --- a/drivers/gpu/drm/i915/intel_csr.c
> > > +++ b/drivers/gpu/drm/i915/intel_csr.c
> > > @@ -41,15 +41,15 @@
> > >   * be moved to FW_FAILED.
> > >   */
> > >  
> > > -#define I915_CSR_KBL "i915/kbl_dmc_ver1_01.bin"
> > > +#define I915_CSR_KBL "i915/kbl_dmc_ver1.bin"
> > >  MODULE_FIRMWARE(I915_CSR_KBL);
> > >  #define KBL_CSR_VERSION_REQUIRED	CSR_VERSION(1, 1)
> > >  
> > > -#define I915_CSR_SKL "i915/skl_dmc_ver1_26.bin"
> > > +#define I915_CSR_SKL "i915/skl_dmc_ver1.bin"
> > >  MODULE_FIRMWARE(I915_CSR_SKL);
> > >  #define SKL_CSR_VERSION_REQUIRED	CSR_VERSION(1, 26)
> > >  
> > > -#define I915_CSR_BXT "i915/bxt_dmc_ver1_07.bin"
> > > +#define I915_CSR_BXT "i915/bxt_dmc_ver1.bin"
> > >  MODULE_FIRMWARE(I915_CSR_BXT);
> > >  #define BXT_CSR_VERSION_REQUIRED	CSR_VERSION(1, 7)
> > >