Re: [PATCH 03/14] drm/i915/dpio: s/VLV_PLL_DW9_BCAST/VLV_PCS_DW17_BCAST/

[Jani Nikula <jani.nikula@linux.intel.com>]

On Mon, 22 Apr 2024, Ville Syrjala <ville.syrjala@linux.intel.com> wrote:
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
>
> VLV_PLL_DW9_BCAST is actually VLV_PCS_DW17_BCAST. The address
> does kinda look like it goes to the PLL block on a first glance,
> but broadcast is special and doesn't even exist for the PLL
> (only PCS and TX have it).
>
> The fact that we use a broadcast write here is a bit sketchy
> IMO since we're now blasting the register to all PCS splines
> across the whole PHY. So the PCS registers in the other channel
> (ie. other pipe/port) will also be written. But I guess the
> fact that we always write the same value should make this a nop
> even if the other channel is already enabled (assuming the VBIOS/GOP
> didn't screw up and use some other value...).
>
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

I'll take your word for it. The patch does what the commit message says,

Reviewed-by: Jani Nikula <jani.nikula@intel.com>

> ---
>  drivers/gpu/drm/i915/display/intel_dpll.c | 2 +-
>  drivers/gpu/drm/i915/i915_reg.h           | 3 ++-
>  2 files changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_dpll.c b/drivers/gpu/drm/i915/display/intel_dpll.c
> index 6693beafe9c0..7e8aca3c87ec 100644
> --- a/drivers/gpu/drm/i915/display/intel_dpll.c
> +++ b/drivers/gpu/drm/i915/display/intel_dpll.c
> @@ -1920,7 +1920,7 @@ static void vlv_prepare_pll(const struct intel_crtc_state *crtc_state)
>  		vlv_pllb_recal_opamp(dev_priv, phy);
>  
>  	/* Set up Tx target for periodic Rcomp update */
> -	vlv_dpio_write(dev_priv, phy, VLV_PLL_DW9_BCAST, 0x0100000f);
> +	vlv_dpio_write(dev_priv, phy, VLV_PCS_DW17_BCAST, 0x0100000f);
>  
>  	/* Disable target IRef on PLL */
>  	reg_val = vlv_dpio_read(dev_priv, phy, VLV_PLL_DW8(pipe));
> diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
> index a2fadcbe0932..8f3c83d2ab8d 100644
> --- a/drivers/gpu/drm/i915/i915_reg.h
> +++ b/drivers/gpu/drm/i915/i915_reg.h
> @@ -233,7 +233,6 @@
>  #define _VLV_PLL_DW8_CH1		0x8060
>  #define VLV_PLL_DW8(ch) _PIPE(ch, _VLV_PLL_DW8_CH0, _VLV_PLL_DW8_CH1)
>  
> -#define VLV_PLL_DW9_BCAST		0xc044
>  #define _VLV_PLL_DW9_CH0		0x8044
>  #define _VLV_PLL_DW9_CH1		0x8064
>  #define VLV_PLL_DW9(ch) _PIPE(ch, _VLV_PLL_DW9_CH0, _VLV_PLL_DW9_CH1)
> @@ -370,6 +369,8 @@
>  #define _VLV_PCS_DW14_CH1		0x8438
>  #define	VLV_PCS_DW14(ch) _PORT(ch, _VLV_PCS_DW14_CH0, _VLV_PCS_DW14_CH1)
>  
> +#define VLV_PCS_DW17_BCAST		0xc044
> +
>  #define _VLV_PCS_DW23_CH0		0x825c
>  #define _VLV_PCS_DW23_CH1		0x845c
>  #define VLV_PCS_DW23(ch) _PORT(ch, _VLV_PCS_DW23_CH0, _VLV_PCS_DW23_CH1)

-- 
Jani Nikula, Intel