On Wed, 15 Feb 2012 11:39:47 -0800 Eric Anholt <eric at anholt.net> wrote: > On Tue, 14 Feb 2012 22:09:11 +0100, Ben Widawsky <ben at bwidawsk.net> wrote: > > From: Ben Widawsky <bwidawsk at gmail.com> > > > > The GPUs can have different default context layouts, and the sizes could > > vary based on platform or BIOS. In order to back the context object with > > a properly sized BO, we must read this register in order to find out a > > sufficient size. > > > > Thankfully (sarcarm!), the register moves and changes meanings > > throughout generations. > > > > CTX and CXT differences are intentional as that is how it is in the > > documentation (prior to GEN6 it was CXT). > > > > Signed-off-by: Ben Widawsky <ben at bwidawsk.net> > > --- > > drivers/gpu/drm/i915/i915_reg.h | 13 +++++++++++++ > > 1 files changed, 13 insertions(+), 0 deletions(-) > > > > diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h > > index 0c785af..5e61e79 100644 > > --- a/drivers/gpu/drm/i915/i915_reg.h > > +++ b/drivers/gpu/drm/i915/i915_reg.h > > @@ -1361,6 +1361,19 @@ > > */ > > #define CCID 0x2180 > > #define CCID_EN (1<<0) > > +#define CXT_SIZE 0x21a0 > > +#define GEN6_CXT_RENDER_SIZE ((I915_READ(CXT_SIZE) >> 12) & 0x3f) > > +#define GEN6_CXT_EXTENDED_SIZE ((I915_READ(CXT_SIZE) >> 6) & 0x3f) > > +#define GEN6_CXT_PIPELINE_SIZE ((I915_READ(CXT_SIZE) >> 0) & 0x3f) > > +#define GEN6_CXT_TOTAL_SIZE (GEN6_CXT_RENDER_SIZE + GEN6_CXT_EXTENDED_SIZE + GEN6_CXT_PIPELINE_SIZE) > > +#define GEN7_CTX_SIZE 0x21a8 > > +#define GEN7_CTX_RENDER_SIZE ((I915_READ(GEN7_CTX_SIZE) >> 16) & 0x3f) > > +#define GEN7_CTX_EXTENDED_SIZE ((I915_READ(GEN7_CTX_SIZE) >> 9) & 0x7f) > > +#define GEN7_CTX_GT1_SIZE ((I915_READ(GEN7_CTX_SIZE) >> 6) & 0x7) > > +#define GEN7_CTX_VFSTATE_SIZE ((I915_READ(GEN7_CTX_SIZE) >> 0) & 0x3f) > > +#define GEN7_CTX_TOTAL_SIZE (GEN7_CTX_RENDER_SIZE + GEN7_CTX_EXTENDED_SIZE \ > > + + GEN7_CTX_GT1_SIZE + GEN7_CTX_VFSTATE_SIZE) > > + > > I was surprised to see register reads in i915_reg.h definitions. I'd > rather see this folded into the one callsite, and just the reg numbers > in i915_reg.h. This will be fixed. > > There's a bit of a discrepancy here -- CXT vs CTX. The docs appear to > actually use CXT, which I will probably never type successfully since > contexts are "ctx" all over my other code. Still, consistently using > the docs' spelling is probably better than inconsistently using it :) I think maybe a comment warning the reader of the typo could help.
