Re: [PATCH] drm/i915: Enable pixel replicated modes on BDW and HSW.

From: Daniel Vetter <daniel@ffwll.ch>
To: clinton.a.taylor@intel.com
Cc: Intel-gfx@lists.freedesktop.org
Subject: Re: [PATCH] drm/i915: Enable pixel replicated modes on BDW and HSW.
Date: Wed, 24 Sep 2014 10:51:49 +0200	[thread overview]
Message-ID: <20140924085149.GP15734@phenom.ffwll.local> (raw)
In-Reply-To: <1411495616-21883-1-git-send-email-clinton.a.taylor@intel.com>

On Tue, Sep 23, 2014 at 11:06:56AM -0700, clinton.a.taylor@intel.com wrote:
> From: Clint Taylor <clinton.a.taylor@intel.com>
> 
> Haswell and later silicon has added a new pixel replication register
> to the pipe timings for each transcoder. Now in addition to the
> DPLL_A_MD register for the pixel clock double, we also need to write to
> the TRANS_MULT_n (0x6002c) register to double the pixel data. Writing
> to the DPLL only double the pixel clock.
> 
> Signed-off-by: Clint Taylor <clinton.a.taylor@intel.com>
> ---
>  drivers/gpu/drm/i915/i915_reg.h      |    3 +++
>  drivers/gpu/drm/i915/intel_display.c |    6 +++++-
>  2 files changed, 8 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
> index 15c0eaa..7c078d9 100644
> --- a/drivers/gpu/drm/i915/i915_reg.h
> +++ b/drivers/gpu/drm/i915/i915_reg.h
> @@ -2431,6 +2431,7 @@ enum punit_power_well {
>  #define _PIPEASRC	0x6001c
>  #define _BCLRPAT_A	0x60020
>  #define _VSYNCSHIFT_A	0x60028
> +#define _MULTIPLY_A	0x6002c
>  
>  /* Pipe B timing regs */
>  #define _HTOTAL_B	0x61000
> @@ -2442,6 +2443,7 @@ enum punit_power_well {
>  #define _PIPEBSRC	0x6101c
>  #define _BCLRPAT_B	0x61020
>  #define _VSYNCSHIFT_B	0x61028
> +#define _MULTIPLY_B	0x6102c
>  
>  #define TRANSCODER_A_OFFSET 0x60000
>  #define TRANSCODER_B_OFFSET 0x61000
> @@ -2462,6 +2464,7 @@ enum punit_power_well {
>  #define BCLRPAT(trans) _TRANSCODER2(trans, _BCLRPAT_A)
>  #define VSYNCSHIFT(trans) _TRANSCODER2(trans, _VSYNCSHIFT_A)
>  #define PIPESRC(trans) _TRANSCODER2(trans, _PIPEASRC)
> +#define MULTIPLY(trans) _TRANSCODER2(trans, _MULTIPLY_A)

MULTIPLY is a bit generic and doesn't even match Bspec lingo. I'd just go
with PIPE_MULTI instead to match Bspec and give it a nice PIPE_ prefix.
>  
>  /* HSW+ eDP PSR registers */
>  #define EDP_PSR_BASE(dev)                       (IS_HASWELL(dev) ? 0x64800 : 0x6f800)
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index c092ff4..e58fcde 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -4152,6 +4152,9 @@ static void haswell_crtc_enable(struct drm_crtc *crtc)
>  
>  	intel_set_pipe_timings(intel_crtc);
>  
> +	I915_WRITE(MULTIPLY(intel_crtc->config.cpu_transcoder),

This register is per-pipe, so needs to be indexed with intel_crtc->pipe.
Same below.

Otherwise this loooks good.
-Daniel

> +			    intel_crtc->config.pixel_multiplier - 1);
> +
>  	if (intel_crtc->config.has_pch_encoder) {
>  		intel_cpu_transcoder_set_m_n(intel_crtc,
>  				     &intel_crtc->config.fdi_m_n, NULL);
> @@ -7811,7 +7814,8 @@ static bool haswell_get_pipe_config(struct intel_crtc *crtc,
>  		pipe_config->ips_enabled = hsw_crtc_supports_ips(crtc) &&
>  			(I915_READ(IPS_CTL) & IPS_ENABLE);
>  
> -	pipe_config->pixel_multiplier = 1;
> +	pipe_config->pixel_multiplier =
> +			I915_READ(MULTIPLY(pipe_config->cpu_transcoder)) + 1;
>  
>  	return true;
>  }
> -- 
> 1.7.9.5
> 
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> http://lists.freedesktop.org/mailman/listinfo/intel-gfx

-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch