[Intel-gfx] [PATCH 1/4] drm/i915: Gather the HDMI level shifter logic into one place

2014-08-01 Thread Damien Lespiau 
The knowledge about the HDMI/DVI DDI translation table was scattered
around.
  - info->hdmi_level_shift was initialized with 6, the index of the 800
mV, 0dB translation
  - A check on the VBT value was done to ensure it wasn't overflowing
the translation table (< 0xC)
  - The actual programming was done in intel_ddi.c

As we need to change that knowledge for Broadwell, let's gather
everything into one place.

Signed-off-by: Damien Lespiau 
---
 drivers/gpu/drm/i915/i915_drv.h   |  6 ++
 drivers/gpu/drm/i915/intel_bios.c | 13 +
 drivers/gpu/drm/i915/intel_ddi.c  | 14 +-
 3 files changed, 24 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index d604f4f..2e41616 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1229,6 +1229,12 @@ enum modeset_restore {
 };
 
 struct ddi_vbt_port_info {
+   /*
+* This is an index in the HDMI/DVI DDI buffer translation table.
+* The special value HDMI_LEVEL_SHIFT_UNKNOWN means the VBT didn't
+* populate this field.
+*/
+#define HDMI_LEVEL_SHIFT_UNKNOWN   0xff
uint8_t hdmi_level_shift;
 
uint8_t supports_dvi:1;
diff --git a/drivers/gpu/drm/i915/intel_bios.c 
b/drivers/gpu/drm/i915/intel_bios.c
index a669550..031c565 100644
--- a/drivers/gpu/drm/i915/intel_bios.c
+++ b/drivers/gpu/drm/i915/intel_bios.c
@@ -976,12 +976,10 @@ static void parse_ddi_port(struct drm_i915_private 
*dev_priv, enum port port,
if (bdb->version >= 158) {
/* The VBT HDMI level shift values match the table we have. */
hdmi_level_shift = child->raw[7] & 0xF;
-   if (hdmi_level_shift < 0xC) {
-   DRM_DEBUG_KMS("VBT HDMI level shift for port %c: %d\n",
- port_name(port),
- hdmi_level_shift);
-   info->hdmi_level_shift = hdmi_level_shift;
-   }
+   DRM_DEBUG_KMS("VBT HDMI level shift for port %c: %d\n",
+ port_name(port),
+ hdmi_level_shift);
+   info->hdmi_level_shift = hdmi_level_shift;
}
 }
 
@@ -1114,8 +1112,7 @@ init_vbt_defaults(struct drm_i915_private *dev_priv)
struct ddi_vbt_port_info *info =
&dev_priv->vbt.ddi_port_info[port];
 
-   /* Recommended BSpec default: 800mV 0dB. */
-   info->hdmi_level_shift = 6;
+   info->hdmi_level_shift = HDMI_LEVEL_SHIFT_UNKNOWN;
 
info->supports_dvi = (port != PORT_A && port != PORT_E);
info->supports_hdmi = info->supports_dvi;
diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c
index a6024de..80e2a42 100644
--- a/drivers/gpu/drm/i915/intel_ddi.c
+++ b/drivers/gpu/drm/i915/intel_ddi.c
@@ -145,7 +145,7 @@ static void intel_prepare_ddi_buffers(struct drm_device 
*dev, enum port port)
 {
struct drm_i915_private *dev_priv = dev->dev_private;
u32 reg;
-   int i;
+   int i, n_hdmi_entries, hdmi_800mV_0dB;
int hdmi_level = dev_priv->vbt.ddi_port_info[port].hdmi_level_shift;
const u32 *ddi_translations_fdi;
const u32 *ddi_translations_dp;
@@ -156,15 +156,21 @@ static void intel_prepare_ddi_buffers(struct drm_device 
*dev, enum port port)
ddi_translations_fdi = bdw_ddi_translations_fdi;
ddi_translations_dp = bdw_ddi_translations_dp;
ddi_translations_edp = bdw_ddi_translations_edp;
+   n_hdmi_entries = ARRAY_SIZE(hsw_ddi_translations_hdmi);
+   hdmi_800mV_0dB = 6;
} else if (IS_HASWELL(dev)) {
ddi_translations_fdi = hsw_ddi_translations_fdi;
ddi_translations_dp = hsw_ddi_translations_dp;
ddi_translations_edp = hsw_ddi_translations_dp;
+   n_hdmi_entries = ARRAY_SIZE(hsw_ddi_translations_hdmi);
+   hdmi_800mV_0dB = 6;
} else {
WARN(1, "ddi translation table missing\n");
ddi_translations_edp = bdw_ddi_translations_dp;
ddi_translations_fdi = bdw_ddi_translations_fdi;
ddi_translations_dp = bdw_ddi_translations_dp;
+   n_hdmi_entries = ARRAY_SIZE(hsw_ddi_translations_hdmi);
+   hdmi_800mV_0dB = 6;
}
 
switch (port) {
@@ -193,6 +199,12 @@ static void intel_prepare_ddi_buffers(struct drm_device 
*dev, enum port port)
I915_WRITE(reg, ddi_translations[i]);
reg += 4;
}
+
+   /* Choose a good default if VBT is badly populated */
+   if (hdmi_level == HDMI_LEVEL_SHIFT_UNKNOWN ||
+   hdmi_level >= n_hdmi_entries)
+   hdmi_level = hdmi_800mV_0dB;
+
/* Entry 9 is for HDMI: */
for (i = 0; i < 2; i++) {
I915_WRI

Re: [Intel-gfx] [PATCH 1/4] drm/i915: Gather the HDMI level shifter logic into one place

2014-08-01 Thread Paulo Zanoni 
2014-08-01 7:07 GMT-03:00 Damien Lespiau :
> The knowledge about the HDMI/DVI DDI translation table was scattered
> around.
>   - info->hdmi_level_shift was initialized with 6, the index of the 800
> mV, 0dB translation
>   - A check on the VBT value was done to ensure it wasn't overflowing
> the translation table (< 0xC)
>   - The actual programming was done in intel_ddi.c
>
> As we need to change that knowledge for Broadwell, let's gather
> everything into one place.

Yeah, it's much better this way.
Reviewed-by: Paulo Zanoni 

>
> Signed-off-by: Damien Lespiau 
> ---
>  drivers/gpu/drm/i915/i915_drv.h   |  6 ++
>  drivers/gpu/drm/i915/intel_bios.c | 13 +
>  drivers/gpu/drm/i915/intel_ddi.c  | 14 +-
>  3 files changed, 24 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index d604f4f..2e41616 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -1229,6 +1229,12 @@ enum modeset_restore {
>  };
>
>  struct ddi_vbt_port_info {
> +   /*
> +* This is an index in the HDMI/DVI DDI buffer translation table.
> +* The special value HDMI_LEVEL_SHIFT_UNKNOWN means the VBT didn't
> +* populate this field.
> +*/
> +#define HDMI_LEVEL_SHIFT_UNKNOWN   0xff
> uint8_t hdmi_level_shift;
>
> uint8_t supports_dvi:1;
> diff --git a/drivers/gpu/drm/i915/intel_bios.c 
> b/drivers/gpu/drm/i915/intel_bios.c
> index a669550..031c565 100644
> --- a/drivers/gpu/drm/i915/intel_bios.c
> +++ b/drivers/gpu/drm/i915/intel_bios.c
> @@ -976,12 +976,10 @@ static void parse_ddi_port(struct drm_i915_private 
> *dev_priv, enum port port,
> if (bdb->version >= 158) {
> /* The VBT HDMI level shift values match the table we have. */
> hdmi_level_shift = child->raw[7] & 0xF;
> -   if (hdmi_level_shift < 0xC) {
> -   DRM_DEBUG_KMS("VBT HDMI level shift for port %c: 
> %d\n",
> - port_name(port),
> - hdmi_level_shift);
> -   info->hdmi_level_shift = hdmi_level_shift;
> -   }
> +   DRM_DEBUG_KMS("VBT HDMI level shift for port %c: %d\n",
> + port_name(port),
> + hdmi_level_shift);
> +   info->hdmi_level_shift = hdmi_level_shift;
> }
>  }
>
> @@ -1114,8 +1112,7 @@ init_vbt_defaults(struct drm_i915_private *dev_priv)
> struct ddi_vbt_port_info *info =
> &dev_priv->vbt.ddi_port_info[port];
>
> -   /* Recommended BSpec default: 800mV 0dB. */
> -   info->hdmi_level_shift = 6;
> +   info->hdmi_level_shift = HDMI_LEVEL_SHIFT_UNKNOWN;
>
> info->supports_dvi = (port != PORT_A && port != PORT_E);
> info->supports_hdmi = info->supports_dvi;
> diff --git a/drivers/gpu/drm/i915/intel_ddi.c 
> b/drivers/gpu/drm/i915/intel_ddi.c
> index a6024de..80e2a42 100644
> --- a/drivers/gpu/drm/i915/intel_ddi.c
> +++ b/drivers/gpu/drm/i915/intel_ddi.c
> @@ -145,7 +145,7 @@ static void intel_prepare_ddi_buffers(struct drm_device 
> *dev, enum port port)
>  {
> struct drm_i915_private *dev_priv = dev->dev_private;
> u32 reg;
> -   int i;
> +   int i, n_hdmi_entries, hdmi_800mV_0dB;
> int hdmi_level = dev_priv->vbt.ddi_port_info[port].hdmi_level_shift;
> const u32 *ddi_translations_fdi;
> const u32 *ddi_translations_dp;
> @@ -156,15 +156,21 @@ static void intel_prepare_ddi_buffers(struct drm_device 
> *dev, enum port port)
> ddi_translations_fdi = bdw_ddi_translations_fdi;
> ddi_translations_dp = bdw_ddi_translations_dp;
> ddi_translations_edp = bdw_ddi_translations_edp;
> +   n_hdmi_entries = ARRAY_SIZE(hsw_ddi_translations_hdmi);
> +   hdmi_800mV_0dB = 6;
> } else if (IS_HASWELL(dev)) {
> ddi_translations_fdi = hsw_ddi_translations_fdi;
> ddi_translations_dp = hsw_ddi_translations_dp;
> ddi_translations_edp = hsw_ddi_translations_dp;
> +   n_hdmi_entries = ARRAY_SIZE(hsw_ddi_translations_hdmi);
> +   hdmi_800mV_0dB = 6;
> } else {
> WARN(1, "ddi translation table missing\n");
> ddi_translations_edp = bdw_ddi_translations_dp;
> ddi_translations_fdi = bdw_ddi_translations_fdi;
> ddi_translations_dp = bdw_ddi_translations_dp;
> +   n_hdmi_entries = ARRAY_SIZE(hsw_ddi_translations_hdmi);
> +   hdmi_800mV_0dB = 6;
> }
>
> switch (port) {
> @@ -193,6 +199,12 @@ static void intel_prepare_ddi_buffers(struct drm_device 
> *dev, enum port port)
> I915_WRITE(reg, ddi_translations[i]);
> reg +=