[Intel-gfx] [PATCH v2 6/6] drm/i915/vlv: Modifying WA 'WaDisableL3Bank2xClockGate for vlv

[Gupta, Sourab]

On Mon, 2014-04-14 at 10:22 +0000, Gupta, Sourab wrote:
> On Tue, 2014-04-01 at 10:53 +0530, sourab gupta wrote:
> > On Tue, 2014-03-25 at 12:23 +0530, sourab gupta wrote:
> > > On Mon, 2014-03-24 at 17:56 +0000, Lespiau, Damien wrote:
> > > > On Mon, Mar 24, 2014 at 11:00:07PM +0530, sourab.gupta at intel.com wrote:
> > > > > From: Akash Goel <akash.goel at intel.com>
> > > > > 
> > > > > For disabling L3 clock gating we need to set bit 25 of MMIO
> > > > > register 940c. Earlier this was being done by just writing 1
> > > > > into bit 25 and resetting all other bits.
> > > > > This patch modifies the routine to read-modify-write of the
> > > > > register, so that the values of other bits are not destroyed.
> > > > > 
> > > > > v2: Modifying the comments and the patch commit message (Chris)
> > > > 
> > > > This patch commit message lacks the most important information: which
> > > > bit are we setting back to 0 and we shouldn't, and why is that
> > > > important? We do direct writes to other registers in that function (for
> > > > instance (MI_ARB_VLV just below).
> > > > 
> > > Hi Damien,
> > > The reset value of the register is 0x00F80003. Therefore, if we directly
> > > set only bit 25 to 1, without caring about other bits, the following reg
> > > bits will be affected (bits 1:0, bits 23:19).
> > > This doesn't seem to be the case with other regs where we are writing
> > > directly (MI_ARB_VLV ) whose default value is 0.
> > > So, by this commit we're just trying to set only the bit which we really
> > > want to change.
> > > 
> > > Regards,
> > > Sourab
> > > 
> > > 
> > Hi Damien,
> > Please provide your comments on the above explanation. I'll add more
> > information to the commit message regarding the same, if it is okay.
> > 
> > Thanks,
> > Sourab
> > 
> Hi Damien,
> 
> Waiting for feedback on the patch and the explanation. Can you please
> let us know if the explained reason is good enough for the patch to be
> considered. If so, it can be added to the commit message.
> 
> Regards,
> Sourab
> 
Hi,
Can you please review this patch. Waiting for the feedback.
Thanks,
Sourab