[Intel-gfx] [PATCH 6/9] drm/i915/bxt: Fix BXT DSI disable sequence

[Bob Paauwe]

On Wed, 8 Feb 2017 16:20:55 +0530
Vidya Srinivas <vidya.srinivas at intel.com> wrote:

> From: Uma Shankar <uma.shankar at intel.com>
> 
> Fix BXT DSI disable sequence as per latest updates in BSpec.
> 
> Signed-off-by: Uma Shankar <uma.shankar at intel.com>
> Signed-off-by: Vidya Srinivas <vidya.srinivas at intel.com>
> ---
>  drivers/gpu/drm/i915/intel_dsi.c | 29 +++++++++++++++++++++++++----
>  1 file changed, 25 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_dsi.c b/drivers/gpu/drm/i915/intel_dsi.c
> index 538755b..808158f 100644
> --- a/drivers/gpu/drm/i915/intel_dsi.c
> +++ b/drivers/gpu/drm/i915/intel_dsi.c
> @@ -632,8 +632,10 @@ static void intel_dsi_disable(struct intel_encoder *encoder)
>  		for_each_dsi_port(port, intel_dsi->ports)
>  			wait_for_dsi_fifo_empty(intel_dsi, port);
>  
> -		intel_dsi_port_disable(encoder);
> -		msleep(2);
> +		if (!IS_BROXTON(dev_priv)) {
> +			intel_dsi_port_disable(encoder);
> +			usleep_range(2000, 2500);
> +		}
>  	}
>  
>  	for_each_dsi_port(port, intel_dsi->ports) {
> @@ -641,7 +643,11 @@ static void intel_dsi_disable(struct intel_encoder *encoder)
>  		I915_WRITE(MIPI_DEVICE_READY(port), 0x0);
>  
>  		intel_dsi_reset_clocks(encoder, port);
> -		I915_WRITE(MIPI_EOT_DISABLE(port), CLOCKSTOP);
> +		temp = 0;
> +		if (intel_dsi->clock_stop) {
> +			temp |= CLOCKSTOP;
> +			I915_WRITE(MIPI_EOT_DISABLE(port), temp);
> +		}

This could be simplified to just
		if (intel_dsi->clock_stop)
			I915_WRITE(MIPI_EOT_DISABLE(port), CLOCKSTOP);


>  
>  		temp = I915_READ(MIPI_DSI_FUNC_PRG(port));
>  		temp &= ~VID_MODE_FORMAT_MASK;
> @@ -707,12 +713,25 @@ static void intel_dsi_post_disable(struct intel_encoder *encoder,
>  	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
>  	struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
>  	u32 val;
> +	enum port port;
>  
>  	DRM_DEBUG_KMS("\n");
>  
>  	intel_dsi_disable(encoder);
>  
> -	intel_dsi_clear_device_ready(encoder);
> +	if (IS_BROXTON(dev_priv)) {
> +		/*
> +		 * Reset the DSI Device ready first for both ports
> +		 * and then port control registers for both ports
> +		 */
> +		for_each_dsi_port(port, intel_dsi->ports)
> +			I915_WRITE(MIPI_DEVICE_READY(port), 0);
> +
> +		for_each_dsi_port(port, intel_dsi->ports)
> +			I915_WRITE(BXT_MIPI_PORT_CTRL(port), 0);
> +	} else {
> +		intel_dsi_clear_device_ready(encoder);
> +	}
>  
>  	if (IS_BROXTON(dev_priv)) {
>  		/* Power down DSI regulator to save power */
> @@ -737,6 +756,8 @@ static void intel_dsi_post_disable(struct intel_encoder *encoder,
>  
>  	drm_panel_unprepare(intel_dsi->panel);
>  
> +	/* Disable Panel */
> +	drm_panel_power_off(intel_dsi->panel);

This depends on the previous patch, which I don't think is the
direction we want to go.  If the code is reworked to not use the
drm_panel interface, then this would need to change also.

>  	msleep(intel_dsi->panel_off_delay);
>  

Do we need to call intel_disable_dsi_pll(encoder) here as part of the
power off?

>  	/* Panel Disable over CRC PMIC */



-- 
--
Bob Paauwe                  
Bob.J.Paauwe at intel.com
IOTG / PED Software Organization
Intel Corp.  Folsom, CA
(916) 356-6193