[PATCH 2/3] drm/radeon: workaround a hw bug on some radeon chipsets with all-0 EDIDs.

[Dave Airlie]

From: Dave Airlie 

Some RS690 chipsets seem to end up with floating connectors, either
a DVI connector isn't actually populated, or an add-in HDMI card
is available but not installed. In this case we seem to get a NULL byte
response for each byte of the i2c transaction, so we detect this
case and if we see it we don't do anymore DDC transactions on this
connector.

I've tested this on my RS690 without the HDMI card installed and
it seems to work fine.

Signed-off-by: Dave Airlie 
---
 drivers/gpu/drm/drm_edid.c |   15 +++
 drivers/gpu/drm/radeon/radeon_connectors.c |7 +++
 include/drm/drm_crtc.h |2 ++
 3 files changed, 24 insertions(+), 0 deletions(-)

diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index 3618d29..0929219 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -258,6 +258,17 @@ drm_do_probe_ddc_edid(struct i2c_adapter *adapter, 
unsigned char *buf,
return ret == 2 ? 0 : -1;
 }

+static bool drm_edid_is_zero(u8 *in_edid, int length)
+{
+   int i;
+   u32 *raw_edid = (u32 *)in_edid;
+
+   for (i = 0; i < length / 4; i++)
+   if (*(raw_edid + i) != 0)
+   return false;
+   return true;
+}
+
 static u8 *
 drm_do_get_edid(struct drm_connector *connector, struct i2c_adapter *adapter)
 {
@@ -273,6 +284,10 @@ drm_do_get_edid(struct drm_connector *connector, struct 
i2c_adapter *adapter)
goto out;
if (drm_edid_block_valid(block))
break;
+   if (i == 0 && drm_edid_is_zero(block, EDID_LENGTH)) {
+   connector->null_edid_counter++;
+   goto carp;
+   }
}
if (i == 4)
goto carp;
diff --git a/drivers/gpu/drm/radeon/radeon_connectors.c 
b/drivers/gpu/drm/radeon/radeon_connectors.c
index 9c2929c..5c3393f 100644
--- a/drivers/gpu/drm/radeon/radeon_connectors.c
+++ b/drivers/gpu/drm/radeon/radeon_connectors.c
@@ -836,6 +836,13 @@ radeon_dvi_detect(struct drm_connector *connector, bool 
force)
if (!radeon_connector->edid) {
DRM_ERROR("%s: probed a monitor but no|invalid EDID\n",
drm_get_connector_name(connector));
+   /* rs690 seems to have a problem with connectors not 
existing and always
+* return a block of 0's. If we see this just stop 
polling on this output */
+   if ((rdev->family == CHIP_RS690) && 
radeon_connector->base.null_edid_counter) {
+   ret = connector_status_disconnected;
+   DRM_ERROR("%s: detected RS690 floating bus bug, 
stopping ddc detect\n", drm_get_connector_name(connector));
+   radeon_connector->ddc_bus = NULL;
+   }
} else {
radeon_connector->use_digital = 
!!(radeon_connector->edid->input & DRM_EDID_INPUT_DIGITAL);

diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index 9573e0c..33d12f8 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -520,6 +520,8 @@ struct drm_connector {
uint32_t encoder_ids[DRM_CONNECTOR_MAX_ENCODER];
uint32_t force_encoder_id;
struct drm_encoder *encoder; /* currently active encoder */
+
+   int null_edid_counter; /* needed to workaround some HW bugs where we 
get all 0s */
 };

 /**
-- 
1.7.5.2

[PATCH 2/3] drm/radeon: workaround a hw bug on some radeon chipsets with all-0 EDIDs.

[Alex Deucher]

On Tue, Jun 14, 2011 at 2:13 AM, Dave Airlie  wrote:
> From: Dave Airlie 
>
> Some RS690 chipsets seem to end up with floating connectors, either
> a DVI connector isn't actually populated, or an add-in HDMI card
> is available but not installed. In this case we seem to get a NULL byte
> response for each byte of the i2c transaction, so we detect this
> case and if we see it we don't do anymore DDC transactions on this
> connector.
>
> I've tested this on my RS690 without the HDMI card installed and
> it seems to work fine.
>
> Signed-off-by: Dave Airlie 

Just one comment below, but other than that:

Reviewed-by: Alex Deucher 

> ---
> ?drivers/gpu/drm/drm_edid.c ? ? ? ? ? ? ? ? | ? 15 +++
> ?drivers/gpu/drm/radeon/radeon_connectors.c | ? ?7 +++
> ?include/drm/drm_crtc.h ? ? ? ? ? ? ? ? ? ? | ? ?2 ++
> ?3 files changed, 24 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
> index 3618d29..0929219 100644
> --- a/drivers/gpu/drm/drm_edid.c
> +++ b/drivers/gpu/drm/drm_edid.c
> @@ -258,6 +258,17 @@ drm_do_probe_ddc_edid(struct i2c_adapter *adapter, 
> unsigned char *buf,
> ? ? ? ?return ret == 2 ? 0 : -1;
> ?}
>
> +static bool drm_edid_is_zero(u8 *in_edid, int length)
> +{
> + ? ? ? int i;
> + ? ? ? u32 *raw_edid = (u32 *)in_edid;
> +
> + ? ? ? for (i = 0; i < length / 4; i++)
> + ? ? ? ? ? ? ? if (*(raw_edid + i) != 0)
> + ? ? ? ? ? ? ? ? ? ? ? return false;
> + ? ? ? return true;
> +}
> +
> ?static u8 *
> ?drm_do_get_edid(struct drm_connector *connector, struct i2c_adapter *adapter)
> ?{
> @@ -273,6 +284,10 @@ drm_do_get_edid(struct drm_connector *connector, struct 
> i2c_adapter *adapter)
> ? ? ? ? ? ? ? ? ? ? ? ?goto out;
> ? ? ? ? ? ? ? ?if (drm_edid_block_valid(block))
> ? ? ? ? ? ? ? ? ? ? ? ?break;
> + ? ? ? ? ? ? ? if (i == 0 && drm_edid_is_zero(block, EDID_LENGTH)) {
> + ? ? ? ? ? ? ? ? ? ? ? connector->null_edid_counter++;
> + ? ? ? ? ? ? ? ? ? ? ? goto carp;
> + ? ? ? ? ? ? ? }
> ? ? ? ?}
> ? ? ? ?if (i == 4)
> ? ? ? ? ? ? ? ?goto carp;
> diff --git a/drivers/gpu/drm/radeon/radeon_connectors.c 
> b/drivers/gpu/drm/radeon/radeon_connectors.c
> index 9c2929c..5c3393f 100644
> --- a/drivers/gpu/drm/radeon/radeon_connectors.c
> +++ b/drivers/gpu/drm/radeon/radeon_connectors.c
> @@ -836,6 +836,13 @@ radeon_dvi_detect(struct drm_connector *connector, bool 
> force)
> ? ? ? ? ? ? ? ?if (!radeon_connector->edid) {
> ? ? ? ? ? ? ? ? ? ? ? ?DRM_ERROR("%s: probed a monitor but no|invalid EDID\n",
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?drm_get_connector_name(connector));
> + ? ? ? ? ? ? ? ? ? ? ? /* rs690 seems to have a problem with connectors not 
> existing and always
> + ? ? ? ? ? ? ? ? ? ? ? ?* return a block of 0's. If we see this just stop 
> polling on this output */
> + ? ? ? ? ? ? ? ? ? ? ? if ((rdev->family == CHIP_RS690) && 
> radeon_connector->base.null_edid_counter) {

You may want to extend this to RS740 as well since IIRC they were pin
compatible with RS690 and showed up in a lot of similar setups.

> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ret = connector_status_disconnected;
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? DRM_ERROR("%s: detected RS690 floating bus 
> bug, stopping ddc detect\n", drm_get_connector_name(connector));
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? radeon_connector->ddc_bus = NULL;
> + ? ? ? ? ? ? ? ? ? ? ? }
> ? ? ? ? ? ? ? ?} else {
> ? ? ? ? ? ? ? ? ? ? ? ?radeon_connector->use_digital = 
> !!(radeon_connector->edid->input & DRM_EDID_INPUT_DIGITAL);
>
> diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
> index 9573e0c..33d12f8 100644
> --- a/include/drm/drm_crtc.h
> +++ b/include/drm/drm_crtc.h
> @@ -520,6 +520,8 @@ struct drm_connector {
> ? ? ? ?uint32_t encoder_ids[DRM_CONNECTOR_MAX_ENCODER];
> ? ? ? ?uint32_t force_encoder_id;
> ? ? ? ?struct drm_encoder *encoder; /* currently active encoder */
> +
> + ? ? ? int null_edid_counter; /* needed to workaround some HW bugs where we 
> get all 0s */
> ?};
>
> ?/**
> --
> 1.7.5.2
>
> ___
> dri-devel mailing list
> dri-devel at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/dri-devel
>

[PATCH 2/3] drm/radeon: workaround a hw bug on some radeon chipsets with all-0 EDIDs.

[Dave Airlie]

From: Dave Airlie airl...@linux.ie

Some RS690 chipsets seem to end up with floating connectors, either
a DVI connector isn't actually populated, or an add-in HDMI card
is available but not installed. In this case we seem to get a NULL byte
response for each byte of the i2c transaction, so we detect this
case and if we see it we don't do anymore DDC transactions on this
connector.

I've tested this on my RS690 without the HDMI card installed and
it seems to work fine.

Signed-off-by: Dave Airlie airl...@redhat.com
---
 drivers/gpu/drm/drm_edid.c |   15 +++
 drivers/gpu/drm/radeon/radeon_connectors.c |7 +++
 include/drm/drm_crtc.h |2 ++
 3 files changed, 24 insertions(+), 0 deletions(-)

diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index 3618d29..0929219 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -258,6 +258,17 @@ drm_do_probe_ddc_edid(struct i2c_adapter *adapter, 
unsigned char *buf,
return ret == 2 ? 0 : -1;
 }
 
+static bool drm_edid_is_zero(u8 *in_edid, int length)
+{
+   int i;
+   u32 *raw_edid = (u32 *)in_edid;
+
+   for (i = 0; i  length / 4; i++)
+   if (*(raw_edid + i) != 0)
+   return false;
+   return true;
+}
+
 static u8 *
 drm_do_get_edid(struct drm_connector *connector, struct i2c_adapter *adapter)
 {
@@ -273,6 +284,10 @@ drm_do_get_edid(struct drm_connector *connector, struct 
i2c_adapter *adapter)
goto out;
if (drm_edid_block_valid(block))
break;
+   if (i == 0  drm_edid_is_zero(block, EDID_LENGTH)) {
+   connector-null_edid_counter++;
+   goto carp;
+   }
}
if (i == 4)
goto carp;
diff --git a/drivers/gpu/drm/radeon/radeon_connectors.c 
b/drivers/gpu/drm/radeon/radeon_connectors.c
index 9c2929c..5c3393f 100644
--- a/drivers/gpu/drm/radeon/radeon_connectors.c
+++ b/drivers/gpu/drm/radeon/radeon_connectors.c
@@ -836,6 +836,13 @@ radeon_dvi_detect(struct drm_connector *connector, bool 
force)
if (!radeon_connector-edid) {
DRM_ERROR(%s: probed a monitor but no|invalid EDID\n,
drm_get_connector_name(connector));
+   /* rs690 seems to have a problem with connectors not 
existing and always
+* return a block of 0's. If we see this just stop 
polling on this output */
+   if ((rdev-family == CHIP_RS690)  
radeon_connector-base.null_edid_counter) {
+   ret = connector_status_disconnected;
+   DRM_ERROR(%s: detected RS690 floating bus bug, 
stopping ddc detect\n, drm_get_connector_name(connector));
+   radeon_connector-ddc_bus = NULL;
+   }
} else {
radeon_connector-use_digital = 
!!(radeon_connector-edid-input  DRM_EDID_INPUT_DIGITAL);
 
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index 9573e0c..33d12f8 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -520,6 +520,8 @@ struct drm_connector {
uint32_t encoder_ids[DRM_CONNECTOR_MAX_ENCODER];
uint32_t force_encoder_id;
struct drm_encoder *encoder; /* currently active encoder */
+
+   int null_edid_counter; /* needed to workaround some HW bugs where we 
get all 0s */
 };
 
 /**
-- 
1.7.5.2

___
dri-devel mailing list
dri-devel@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/dri-devel

Re: [PATCH 2/3] drm/radeon: workaround a hw bug on some radeon chipsets with all-0 EDIDs.

[Alex Deucher]

On Tue, Jun 14, 2011 at 2:13 AM, Dave Airlie airl...@gmail.com wrote:
 From: Dave Airlie airl...@linux.ie

 Some RS690 chipsets seem to end up with floating connectors, either
 a DVI connector isn't actually populated, or an add-in HDMI card
 is available but not installed. In this case we seem to get a NULL byte
 response for each byte of the i2c transaction, so we detect this
 case and if we see it we don't do anymore DDC transactions on this
 connector.

 I've tested this on my RS690 without the HDMI card installed and
 it seems to work fine.

 Signed-off-by: Dave Airlie airl...@redhat.com

Just one comment below, but other than that:

Reviewed-by: Alex Deucher alexdeuc...@gmail.com

 ---
  drivers/gpu/drm/drm_edid.c                 |   15 +++
  drivers/gpu/drm/radeon/radeon_connectors.c |    7 +++
  include/drm/drm_crtc.h                     |    2 ++
  3 files changed, 24 insertions(+), 0 deletions(-)

 diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
 index 3618d29..0929219 100644
 --- a/drivers/gpu/drm/drm_edid.c
 +++ b/drivers/gpu/drm/drm_edid.c
 @@ -258,6 +258,17 @@ drm_do_probe_ddc_edid(struct i2c_adapter *adapter, 
 unsigned char *buf,
        return ret == 2 ? 0 : -1;
  }

 +static bool drm_edid_is_zero(u8 *in_edid, int length)
 +{
 +       int i;
 +       u32 *raw_edid = (u32 *)in_edid;
 +
 +       for (i = 0; i  length / 4; i++)
 +               if (*(raw_edid + i) != 0)
 +                       return false;
 +       return true;
 +}
 +
  static u8 *
  drm_do_get_edid(struct drm_connector *connector, struct i2c_adapter *adapter)
  {
 @@ -273,6 +284,10 @@ drm_do_get_edid(struct drm_connector *connector, struct 
 i2c_adapter *adapter)
                        goto out;
                if (drm_edid_block_valid(block))
                        break;
 +               if (i == 0  drm_edid_is_zero(block, EDID_LENGTH)) {
 +                       connector-null_edid_counter++;
 +                       goto carp;
 +               }
        }
        if (i == 4)
                goto carp;
 diff --git a/drivers/gpu/drm/radeon/radeon_connectors.c 
 b/drivers/gpu/drm/radeon/radeon_connectors.c
 index 9c2929c..5c3393f 100644
 --- a/drivers/gpu/drm/radeon/radeon_connectors.c
 +++ b/drivers/gpu/drm/radeon/radeon_connectors.c
 @@ -836,6 +836,13 @@ radeon_dvi_detect(struct drm_connector *connector, bool 
 force)
                if (!radeon_connector-edid) {
                        DRM_ERROR(%s: probed a monitor but no|invalid EDID\n,
                                        drm_get_connector_name(connector));
 +                       /* rs690 seems to have a problem with connectors not 
 existing and always
 +                        * return a block of 0's. If we see this just stop 
 polling on this output */
 +                       if ((rdev-family == CHIP_RS690)  
 radeon_connector-base.null_edid_counter) {

You may want to extend this to RS740 as well since IIRC they were pin
compatible with RS690 and showed up in a lot of similar setups.

 +                               ret = connector_status_disconnected;
 +                               DRM_ERROR(%s: detected RS690 floating bus 
 bug, stopping ddc detect\n, drm_get_connector_name(connector));
 +                               radeon_connector-ddc_bus = NULL;
 +                       }
                } else {
                        radeon_connector-use_digital = 
 !!(radeon_connector-edid-input  DRM_EDID_INPUT_DIGITAL);

 diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
 index 9573e0c..33d12f8 100644
 --- a/include/drm/drm_crtc.h
 +++ b/include/drm/drm_crtc.h
 @@ -520,6 +520,8 @@ struct drm_connector {
        uint32_t encoder_ids[DRM_CONNECTOR_MAX_ENCODER];
        uint32_t force_encoder_id;
        struct drm_encoder *encoder; /* currently active encoder */
 +
 +       int null_edid_counter; /* needed to workaround some HW bugs where we 
 get all 0s */
  };

  /**
 --
 1.7.5.2

 ___
 dri-devel mailing list
 dri-devel@lists.freedesktop.org
 http://lists.freedesktop.org/mailman/listinfo/dri-devel

___
dri-devel mailing list
dri-devel@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/dri-devel