linux-kernel - Re: [Intel-gfx] [PATCH] drm/i915/skl: Fix typo in DPLL_CFGCR1 definition

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Message-ID: <20160204161128.GO23290@intel.com>
Date:	Thu, 4 Feb 2016 18:11:28 +0200
From:	Ville Syrjälä <ville.syrjala@...ux.intel.com>
To:	Lyude <cpaul@...hat.com>
Cc:	Daniel Vetter <daniel.vetter@...el.com>,
	Jani Nikula <jani.nikula@...ux.intel.com>,
	David Airlie <airlied@...ux.ie>,
	intel-gfx@...ts.freedesktop.org, dri-devel@...ts.freedesktop.org,
	linux-kernel@...r.kernel.org,
	Benjamin Tissoires <btissoir@...hat.com>,
	Rob Clark <rclark@...hat.com>
Subject: Re: [Intel-gfx] [PATCH] drm/i915/skl: Fix typo in DPLL_CFGCR1
 definition

On Thu, Feb 04, 2016 at 10:43:21AM -0500, Lyude wrote:
> We accidentally point both cfgcr registers for the second shared DPLL to
> the same location in i915_reg.h. This results in a lot of hw pipe state
> mismatches whenever we try to do a modeset that requires allocating the
> DPLL to a CRTC:
> 
> [drm:intel_pipe_config_compare [i915]] *ERROR* mismatch in dpll_hw_state.cfgcr1 (expected 0x80000168, found 0x000004a5)
> [drm:intel_pipe_config_compare [i915]] *ERROR* mismatch in base.adjusted_mode.crtc_clock (expected 108000, found 49500)
> [drm:intel_pipe_config_compare [i915]] *ERROR* mismatch in port_clock (expected 108000, found 49500)
> 
> This usually ends up causing blank monitors, since the DPLL never can
> get set to the right clock.
> 
> Fixes: f0f59a00a1 ("drm/i915: Type safe register read/write")

Actually
Fixes: 086f8e84a085 ("drm/i915: Prefix raw register defines with underscore")

That's the second regression from the type safety stuff :( I guess we
still don't have enough testing coverage since this has gone undetected
for so long.

Reviewed-by: Ville Syrjälä <ville.syrjala@...ux.intel.com>

> Signed-off-by: Lyude <cpaul@...hat.com>
> ---
>  drivers/gpu/drm/i915/i915_reg.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
> index 007ae83..b9a564b 100644
> --- a/drivers/gpu/drm/i915/i915_reg.h
> +++ b/drivers/gpu/drm/i915/i915_reg.h
> @@ -7514,7 +7514,7 @@ enum skl_disp_power_wells {
>  #define  DPLL_CFGCR2_PDIV_7 (4<<2)
>  #define  DPLL_CFGCR2_CENTRAL_FREQ_MASK	(3)
>  
> -#define DPLL_CFGCR1(id)	_MMIO_PIPE((id) - SKL_DPLL1, _DPLL1_CFGCR1, _DPLL2_CFGCR2)
> +#define DPLL_CFGCR1(id)	_MMIO_PIPE((id) - SKL_DPLL1, _DPLL1_CFGCR1, _DPLL2_CFGCR1)
>  #define DPLL_CFGCR2(id)	_MMIO_PIPE((id) - SKL_DPLL1, _DPLL1_CFGCR2, _DPLL2_CFGCR2)
>  
>  /* BXT display engine PLL */
> -- 
> 2.5.0
> 
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@...ts.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx

-- 
Ville Syrjälä
Intel OTC

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