[Intel-gfx] [PATCH] drm/i915: Use POSTING_READ in lcpll code

[Paulo Zanoni]

2013/8/21 Daniel Vetter <daniel.vetter at ffwll.ch>:
> If we don't use the return value of a mmio read our coding style is to
> use the POSTING_READ macro. This avoids cluttering the mmio traces.
>
> While at it add the missing posting read in the lcpll enable function
> that Paulo spotted.
>
> v2: Drop the _NOTRACE changes, tracing such wait_for loops in the modeset
> code might actually be rather useful!
>
> Cc: Paulo Zanoni <przanoni at gmail.com>
> Signed-off-by: Daniel Vetter <daniel.vetter at ffwll.ch>

Reviewed-by: Paulo Zanoni <paulo.r.zanoni at intel.com>

> ---
>  drivers/gpu/drm/i915/intel_display.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index 7a40427..937fc5a6 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -6036,13 +6036,14 @@ void hsw_restore_lcpll(struct drm_i915_private *dev_priv)
>         if (val & LCPLL_POWER_DOWN_ALLOW) {
>                 val &= ~LCPLL_POWER_DOWN_ALLOW;
>                 I915_WRITE(LCPLL_CTL, val);
> +               POSTING_READ(LCPLL_CTL);
>         }
>
>         val = I915_READ(D_COMP);
>         val |= D_COMP_COMP_FORCE;
>         val &= ~D_COMP_COMP_DISABLE;
>         I915_WRITE(D_COMP, val);
> -       I915_READ(D_COMP);
> +       POSTING_READ(D_COMP);
>
>         val = I915_READ(LCPLL_CTL);
>         val &= ~LCPLL_PLL_DISABLE;
> --
> 1.8.4.rc3
>



-- 
Paulo Zanoni