[Intel-gfx] [PATCH 17/17] drm/i915: Add comments about units of latency values

[Ville Syrjälä]

On Fri, Aug 02, 2013 at 12:58:07PM -0300, Paulo Zanoni wrote:
> 2013/8/1  <ville.syrjala at linux.intel.com>:
> > From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> >
> > All the ILK+ WM compute functions take the latency values in 0.1us
> > units. Add a few comments to remind people about that.
> >
> > Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 
> Reviewed-by: Paulo Zanoni <paulo.r.zanoni at intel.com>
> 
> (but I would have written Latency instead of latency :P )

I was considering going for full blown kernel-doc, but since we don't
currently generate docs for i915, i just used the name of the argument
in question.

> > ---
> >  drivers/gpu/drm/i915/intel_pm.c | 17 ++++++++++++++---
> >  1 file changed, 14 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> > index 5fe8c4e..51f445f 100644
> > --- a/drivers/gpu/drm/i915/intel_pm.c
> > +++ b/drivers/gpu/drm/i915/intel_pm.c
> > @@ -2108,6 +2108,7 @@ static uint32_t ilk_pipe_pixel_rate(struct drm_device *dev,
> >         return pixel_rate;
> >  }
> >
> > +/* latency must be in 0.1us units. */
> >  static uint32_t ilk_wm_method1(uint32_t pixel_rate, uint8_t bytes_per_pixel,
> >                                uint32_t latency)
> >  {
> > @@ -2122,6 +2123,7 @@ static uint32_t ilk_wm_method1(uint32_t pixel_rate, uint8_t bytes_per_pixel,
> >         return ret;
> >  }
> >
> > +/* latency must be in 0.1us units. */
> >  static uint32_t ilk_wm_method2(uint32_t pixel_rate, uint32_t pipe_htotal,
> >                                uint32_t horiz_pixels, uint8_t bytes_per_pixel,
> >                                uint32_t latency)
> > @@ -2185,7 +2187,10 @@ enum hsw_data_buf_partitioning {
> >         HSW_DATA_BUF_PART_5_6,
> >  };
> >
> > -/* For both WM_PIPE and WM_LP. */
> > +/*
> > + * For both WM_PIPE and WM_LP.
> > + * mem_value must be in 0.1us units.
> > + */
> >  static uint32_t ilk_compute_pri_wm(struct hsw_pipe_wm_parameters *params,
> >                                    uint32_t mem_value,
> >                                    bool is_lp)
> > @@ -2212,7 +2217,10 @@ static uint32_t ilk_compute_pri_wm(struct hsw_pipe_wm_parameters *params,
> >         return min(method1, method2);
> >  }
> >
> > -/* For both WM_PIPE and WM_LP. */
> > +/*
> > + * For both WM_PIPE and WM_LP.
> > + * mem_value must be in 0.1us units.
> > + */
> >  static uint32_t ilk_compute_spr_wm(struct hsw_pipe_wm_parameters *params,
> >                                    uint32_t mem_value)
> >  {
> > @@ -2232,7 +2240,10 @@ static uint32_t ilk_compute_spr_wm(struct hsw_pipe_wm_parameters *params,
> >         return min(method1, method2);
> >  }
> >
> > -/* For both WM_PIPE and WM_LP. */
> > +/*
> > + * For both WM_PIPE and WM_LP.
> > + * mem_value must be in 0.1us units.
> > + */
> >  static uint32_t ilk_compute_cur_wm(struct hsw_pipe_wm_parameters *params,
> >                                    uint32_t mem_value)
> >  {
> > --
> > 1.8.1.5
> >
> > _______________________________________________
> > Intel-gfx mailing list
> > Intel-gfx at lists.freedesktop.org
> > http://lists.freedesktop.org/mailman/listinfo/intel-gfx
> 
> 
> 
> -- 
> Paulo Zanoni

-- 
Ville Syrjälä
Intel OTC