On Mon, Jun 08, 2015 at 12:12:41PM +0300, Mika Kuoppala wrote: > Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> writes: > > > On Fri, May 22, 2015 at 08:17:22PM +0300, Mika Kuoppala wrote: > >> We initialize the internal read pointer to zero on init/reset, > >> but only the reset will actually zero the write pointer. > >> This means that on module reload we might re-read context > >> status buffers that were written prior reload. > >> > >> It is safest just to let the hardware keep track of the read pointer, > >> so that we get valid value as there is no driver state involved. > >> > >> Signed-off-by: Mika Kuoppala <mika.kuoppala@xxxxxxxxx> > >> --- > >> drivers/gpu/drm/i915/i915_debugfs.c | 6 +++--- > >> drivers/gpu/drm/i915/intel_lrc.c | 11 ++++------- > >> drivers/gpu/drm/i915/intel_ringbuffer.h | 2 +- > >> 3 files changed, 8 insertions(+), 11 deletions(-) > >> > >> diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c > >> index fece922..b079dd3 100644 > >> --- a/drivers/gpu/drm/i915/i915_debugfs.c > >> +++ b/drivers/gpu/drm/i915/i915_debugfs.c > >> @@ -2026,8 +2026,8 @@ static int i915_execlists(struct seq_file *m, void *data) > >> struct drm_i915_private *dev_priv = dev->dev_private; > >> struct intel_engine_cs *ring; > >> u32 status_pointer; > >> - u8 read_pointer; > >> - u8 write_pointer; > >> + u32 read_pointer; > >> + u32 write_pointer; > > > > I don't follow this change. It seems like this is to avoid having to > > explicitly widen the type when converting the 32bit register value later > > on? > > > > Yes that is the sole purpose. I don't see any drawback. C likes to promote most things to int anyway, so I'm not sure what this widening is all about. -- Ville Syrjälä Intel OTC _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
