Hi!
Since Linux 3.0, a system with a Radeon HD 5450 (1002:68f9) connected to a 27" Apple LED cinema display via an Atlona AT-DP400 Dual Link DVI to Mini DisplayPort converter has started to stop giving screen output on switching from text mode to graphical framebuffer during system startup.
I finally had some time to look at this, and it seems to have stopped working after this commit:
commit df271bec805b42527d864777ed035fcbb42e76c0 Author: Alex Deucher alexdeucher@gmail.com Date: Fri May 20 04:34:15 2011 -0400
drm/radeon/kms: properly handle bpc >8 in atom command tables Signed-off-by: Alex Deucher alexdeucher@gmail.com Signed-off-by: Dave Airlie airlied@redhat.com
...and with the patch below (i.e. reverting part of the commit above) applied to 3.3 I get screen output again.
Even though the monitor seems to have an 8 bit panel, it reports 10 bits per channel in its EDID:
[...] Manufacturer: APP Model 9226 Serial Number 41959462 Made week 38 of 2010 EDID version: 1.4 Digital display 10 bits per primary color channel DisplayPort interface Maximum image size: 60 cm x 34 cm [...]
The (active, dual link) DVI->mDP converter spec sheet says it supports 24 bit color, and I'm guessing that it can't deal with 30. Is the converter at fault here for passing through the EDID unchanged?
Also, what would be the right way to handle this, a kernel command line or module option to limit color depth or something like that? ("Buy a video card with DP output." is a valid answer, I suppose.)
I have no clue at all about graphics, and I have no idea whatsoever what I'm doing here, but I just wanted to post this somewhere for Google to find in case someone else runs into this!
thanks, Lennert
diff --git a/drivers/gpu/drm/radeon/atombios_crtc.c b/drivers/gpu/drm/radeon/atombios_crtc.c index 742f17f..77a6a04 100644 --- a/drivers/gpu/drm/radeon/atombios_crtc.c +++ b/drivers/gpu/drm/radeon/atombios_crtc.c @@ -513,11 +513,9 @@ static u32 atombios_adjust_pll(struct drm_crtc *crtc, struct radeon_device *rdev = dev->dev_private; struct drm_encoder *encoder = NULL; struct radeon_encoder *radeon_encoder = NULL; - struct drm_connector *connector = NULL; u32 adjusted_clock = mode->clock; int encoder_mode = 0; u32 dp_clock = mode->clock; - int bpc = 8; bool is_duallink = false;
/* reset the pll flags */ @@ -549,13 +547,11 @@ static u32 atombios_adjust_pll(struct drm_crtc *crtc, list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) { if (encoder->crtc == crtc) { radeon_encoder = to_radeon_encoder(encoder); - connector = radeon_get_connector_for_encoder(encoder); - if (connector && connector->display_info.bpc) - bpc = connector->display_info.bpc; encoder_mode = atombios_get_encoder_mode(encoder); is_duallink = radeon_dig_monitor_is_duallink(encoder, mode->clock); if ((radeon_encoder->devices & (ATOM_DEVICE_LCD_SUPPORT | ATOM_DEVICE_DFP_SUPPORT)) || (radeon_encoder_get_dp_bridge_encoder_id(encoder) != ENCODER_OBJECT_ID_NONE)) { + struct drm_connector *connector = radeon_get_connector_for_encoder(encoder); if (connector) { struct radeon_connector *radeon_connector = to_radeon_connector(connector); struct radeon_connector_atom_dig *dig_connector = @@ -645,7 +641,7 @@ static u32 atombios_adjust_pll(struct drm_crtc *crtc, if (encoder_mode == ATOM_ENCODER_MODE_HDMI) /* deep color support */ args.v3.sInput.usPixelClock = - cpu_to_le16((mode->clock * bpc / 8) / 10); + cpu_to_le16(mode->clock / 10); if (dig->coherent_mode) args.v3.sInput.ucDispPllConfig |= DISPPLL_CONFIG_COHERENT_MODE; @@ -753,7 +749,6 @@ static void atombios_crtc_program_pll(struct drm_crtc *crtc, u32 fb_div, u32 frac_fb_div, u32 post_div, - int bpc, bool ss_enabled, struct radeon_atom_ss *ss) { @@ -817,15 +812,6 @@ static void atombios_crtc_program_pll(struct drm_crtc *crtc, args.v5.ucMiscInfo = 0; /* HDMI depth, etc. */ if (ss_enabled && (ss->type & ATOM_EXTERNAL_SS_MASK)) args.v5.ucMiscInfo |= PIXEL_CLOCK_V5_MISC_REF_DIV_SRC; - switch (bpc) { - case 8: - default: - args.v5.ucMiscInfo |= PIXEL_CLOCK_V5_MISC_HDMI_24BPP; - break; - case 10: - args.v5.ucMiscInfo |= PIXEL_CLOCK_V5_MISC_HDMI_30BPP; - break; - } args.v5.ucTransmitterID = encoder_id; args.v5.ucEncoderMode = encoder_mode; args.v5.ucPpll = pll_id; @@ -839,21 +825,6 @@ static void atombios_crtc_program_pll(struct drm_crtc *crtc, args.v6.ucMiscInfo = 0; /* HDMI depth, etc. */ if (ss_enabled && (ss->type & ATOM_EXTERNAL_SS_MASK)) args.v6.ucMiscInfo |= PIXEL_CLOCK_V6_MISC_REF_DIV_SRC; - switch (bpc) { - case 8: - default: - args.v6.ucMiscInfo |= PIXEL_CLOCK_V6_MISC_HDMI_24BPP; - break; - case 10: - args.v6.ucMiscInfo |= PIXEL_CLOCK_V6_MISC_HDMI_30BPP; - break; - case 12: - args.v6.ucMiscInfo |= PIXEL_CLOCK_V6_MISC_HDMI_36BPP; - break; - case 16: - args.v6.ucMiscInfo |= PIXEL_CLOCK_V6_MISC_HDMI_48BPP; - break; - } args.v6.ucTransmitterID = encoder_id; args.v6.ucEncoderMode = encoder_mode; args.v6.ucPpll = pll_id; @@ -885,7 +856,6 @@ static void atombios_crtc_set_pll(struct drm_crtc *crtc, struct drm_display_mode int encoder_mode = 0; struct radeon_atom_ss ss; bool ss_enabled = false; - int bpc = 8;
list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) { if (encoder->crtc == crtc) { @@ -922,7 +892,6 @@ static void atombios_crtc_set_pll(struct drm_crtc *crtc, struct drm_display_mode struct radeon_connector_atom_dig *dig_connector = radeon_connector->con_priv; int dp_clock; - bpc = connector->display_info.bpc;
switch (encoder_mode) { case ATOM_ENCODER_MODE_DP_MST: @@ -995,7 +964,7 @@ static void atombios_crtc_set_pll(struct drm_crtc *crtc, struct drm_display_mode
atombios_crtc_program_pll(crtc, radeon_crtc->crtc_id, radeon_crtc->pll_id, encoder_mode, radeon_encoder->encoder_id, mode->clock, - ref_div, fb_div, frac_fb_div, post_div, bpc, ss_enabled, &ss); + ref_div, fb_div, frac_fb_div, post_div, ss_enabled, &ss);
if (ss_enabled) { /* calculate ss amount and step size */ @@ -1587,7 +1556,7 @@ static void atombios_crtc_disable(struct drm_crtc *crtc) case ATOM_PPLL2: /* disable the ppll */ atombios_crtc_program_pll(crtc, radeon_crtc->crtc_id, radeon_crtc->pll_id, - 0, 0, ATOM_DISABLE, 0, 0, 0, 0, 0, false, &ss); + 0, 0, ATOM_DISABLE, 0, 0, 0, 0, false, &ss); break; default: break;
On Thu, Mar 22, 2012 at 8:49 AM, Lennert Buytenhek buytenh@wantstofly.org wrote:
Hi!
Since Linux 3.0, a system with a Radeon HD 5450 (1002:68f9) connected to a 27" Apple LED cinema display via an Atlona AT-DP400 Dual Link DVI to Mini DisplayPort converter has started to stop giving screen output on switching from text mode to graphical framebuffer during system startup.
I finally had some time to look at this, and it seems to have stopped working after this commit:
commit df271bec805b42527d864777ed035fcbb42e76c0 Author: Alex Deucher alexdeucher@gmail.com Date: Fri May 20 04:34:15 2011 -0400
drm/radeon/kms: properly handle bpc >8 in atom command tables
Signed-off-by: Alex Deucher alexdeucher@gmail.com Signed-off-by: Dave Airlie airlied@redhat.com
...and with the patch below (i.e. reverting part of the commit above) applied to 3.3 I get screen output again.
Even though the monitor seems to have an 8 bit panel, it reports 10 bits per channel in its EDID:
[...] Manufacturer: APP Model 9226 Serial Number 41959462 Made week 38 of 2010 EDID version: 1.4 Digital display 10 bits per primary color channel DisplayPort interface Maximum image size: 60 cm x 34 cm [...]
The (active, dual link) DVI->mDP converter spec sheet says it supports 24 bit color, and I'm guessing that it can't deal with 30. Is the converter at fault here for passing through the EDID unchanged?
Also, what would be the right way to handle this, a kernel command line or module option to limit color depth or something like that? ("Buy a video card with DP output." is a valid answer, I suppose.)
I have no clue at all about graphics, and I have no idea whatsoever what I'm doing here, but I just wanted to post this somewhere for Google to find in case someone else runs into this!
I've inquired with out display team on how to best handle this. In the meantime, it's probably best to just default to 8 bpc. Does the attached patch fix your issue?
Alex
thanks, Lennert
diff --git a/drivers/gpu/drm/radeon/atombios_crtc.c b/drivers/gpu/drm/radeon/atombios_crtc.c index 742f17f..77a6a04 100644 --- a/drivers/gpu/drm/radeon/atombios_crtc.c +++ b/drivers/gpu/drm/radeon/atombios_crtc.c @@ -513,11 +513,9 @@ static u32 atombios_adjust_pll(struct drm_crtc *crtc, struct radeon_device *rdev = dev->dev_private; struct drm_encoder *encoder = NULL; struct radeon_encoder *radeon_encoder = NULL;
- struct drm_connector *connector = NULL;
u32 adjusted_clock = mode->clock; int encoder_mode = 0; u32 dp_clock = mode->clock;
- int bpc = 8;
bool is_duallink = false;
/* reset the pll flags */ @@ -549,13 +547,11 @@ static u32 atombios_adjust_pll(struct drm_crtc *crtc, list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) { if (encoder->crtc == crtc) { radeon_encoder = to_radeon_encoder(encoder);
- connector = radeon_get_connector_for_encoder(encoder);
- if (connector && connector->display_info.bpc)
- bpc = connector->display_info.bpc;
encoder_mode = atombios_get_encoder_mode(encoder); is_duallink = radeon_dig_monitor_is_duallink(encoder, mode->clock); if ((radeon_encoder->devices & (ATOM_DEVICE_LCD_SUPPORT | ATOM_DEVICE_DFP_SUPPORT)) || (radeon_encoder_get_dp_bridge_encoder_id(encoder) != ENCODER_OBJECT_ID_NONE)) {
- struct drm_connector *connector = radeon_get_connector_for_encoder(encoder);
if (connector) { struct radeon_connector *radeon_connector = to_radeon_connector(connector); struct radeon_connector_atom_dig *dig_connector = @@ -645,7 +641,7 @@ static u32 atombios_adjust_pll(struct drm_crtc *crtc, if (encoder_mode == ATOM_ENCODER_MODE_HDMI) /* deep color support */ args.v3.sInput.usPixelClock =
- cpu_to_le16((mode->clock * bpc / 8) / 10);
- cpu_to_le16(mode->clock / 10);
if (dig->coherent_mode) args.v3.sInput.ucDispPllConfig |= DISPPLL_CONFIG_COHERENT_MODE; @@ -753,7 +749,6 @@ static void atombios_crtc_program_pll(struct drm_crtc *crtc, u32 fb_div, u32 frac_fb_div, u32 post_div,
- int bpc,
bool ss_enabled, struct radeon_atom_ss *ss) { @@ -817,15 +812,6 @@ static void atombios_crtc_program_pll(struct drm_crtc *crtc, args.v5.ucMiscInfo = 0; /* HDMI depth, etc. */ if (ss_enabled && (ss->type & ATOM_EXTERNAL_SS_MASK)) args.v5.ucMiscInfo |= PIXEL_CLOCK_V5_MISC_REF_DIV_SRC;
- switch (bpc) {
- case 8:
- default:
- args.v5.ucMiscInfo |= PIXEL_CLOCK_V5_MISC_HDMI_24BPP;
- break;
- case 10:
- args.v5.ucMiscInfo |= PIXEL_CLOCK_V5_MISC_HDMI_30BPP;
- break;
- }
args.v5.ucTransmitterID = encoder_id; args.v5.ucEncoderMode = encoder_mode; args.v5.ucPpll = pll_id; @@ -839,21 +825,6 @@ static void atombios_crtc_program_pll(struct drm_crtc *crtc, args.v6.ucMiscInfo = 0; /* HDMI depth, etc. */ if (ss_enabled && (ss->type & ATOM_EXTERNAL_SS_MASK)) args.v6.ucMiscInfo |= PIXEL_CLOCK_V6_MISC_REF_DIV_SRC;
- switch (bpc) {
- case 8:
- default:
- args.v6.ucMiscInfo |= PIXEL_CLOCK_V6_MISC_HDMI_24BPP;
- break;
- case 10:
- args.v6.ucMiscInfo |= PIXEL_CLOCK_V6_MISC_HDMI_30BPP;
- break;
- case 12:
- args.v6.ucMiscInfo |= PIXEL_CLOCK_V6_MISC_HDMI_36BPP;
- break;
- case 16:
- args.v6.ucMiscInfo |= PIXEL_CLOCK_V6_MISC_HDMI_48BPP;
- break;
- }
args.v6.ucTransmitterID = encoder_id; args.v6.ucEncoderMode = encoder_mode; args.v6.ucPpll = pll_id; @@ -885,7 +856,6 @@ static void atombios_crtc_set_pll(struct drm_crtc *crtc, struct drm_display_mode int encoder_mode = 0; struct radeon_atom_ss ss; bool ss_enabled = false;
- int bpc = 8;
list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) { if (encoder->crtc == crtc) { @@ -922,7 +892,6 @@ static void atombios_crtc_set_pll(struct drm_crtc *crtc, struct drm_display_mode struct radeon_connector_atom_dig *dig_connector = radeon_connector->con_priv; int dp_clock;
- bpc = connector->display_info.bpc;
switch (encoder_mode) { case ATOM_ENCODER_MODE_DP_MST: @@ -995,7 +964,7 @@ static void atombios_crtc_set_pll(struct drm_crtc *crtc, struct drm_display_mode
atombios_crtc_program_pll(crtc, radeon_crtc->crtc_id, radeon_crtc->pll_id, encoder_mode, radeon_encoder->encoder_id, mode->clock,
- ref_div, fb_div, frac_fb_div, post_div, bpc, ss_enabled, &ss);
- ref_div, fb_div, frac_fb_div, post_div, ss_enabled, &ss);
if (ss_enabled) { /* calculate ss amount and step size */ @@ -1587,7 +1556,7 @@ static void atombios_crtc_disable(struct drm_crtc *crtc) case ATOM_PPLL2: /* disable the ppll */ atombios_crtc_program_pll(crtc, radeon_crtc->crtc_id, radeon_crtc->pll_id,
- 0, 0, ATOM_DISABLE, 0, 0, 0, 0, 0, false, &ss);
- 0, 0, ATOM_DISABLE, 0, 0, 0, 0, false, &ss);
break; default: break; _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/dri-devel
On Fri, Mar 23, 2012 at 10:59:27AM -0400, Alex Deucher wrote:
Since Linux 3.0, a system with a Radeon HD 5450 (1002:68f9) connected to a 27" Apple LED cinema display via an Atlona AT-DP400 Dual Link DVI to Mini DisplayPort converter has started to stop giving screen output on switching from text mode to graphical framebuffer during system startup.
I finally had some time to look at this, and it seems to have stopped working after this commit:
commit df271bec805b42527d864777ed035fcbb42e76c0 Author: Alex Deucher alexdeucher@gmail.com Date: Fri May 20 04:34:15 2011 -0400
drm/radeon/kms: properly handle bpc >8 in atom command tables
Signed-off-by: Alex Deucher alexdeucher@gmail.com Signed-off-by: Dave Airlie airlied@redhat.com
...and with the patch below (i.e. reverting part of the commit above) applied to 3.3 I get screen output again.
Even though the monitor seems to have an 8 bit panel, it reports 10 bits per channel in its EDID:
[...] Manufacturer: APP Model 9226 Serial Number 41959462 Made week 38 of 2010 EDID version: 1.4 Digital display 10 bits per primary color channel DisplayPort interface Maximum image size: 60 cm x 34 cm [...]
The (active, dual link) DVI->mDP converter spec sheet says it supports 24 bit color, and I'm guessing that it can't deal with 30. Is the converter at fault here for passing through the EDID unchanged?
Also, what would be the right way to handle this, a kernel command line or module option to limit color depth or something like that? ("Buy a video card with DP output." is a valid answer, I suppose.)
I have no clue at all about graphics, and I have no idea whatsoever what I'm doing here, but I just wanted to post this somewhere for Google to find in case someone else runs into this!
I've inquired with out display team on how to best handle this. In the meantime, it's probably best to just default to 8 bpc. Does the attached patch fix your issue?
I've been using the patch below in a custom Fedora 17 kernel RPM, and that seems to fix the issue. Your patch seems to be a superset of this patch, so logically, your patch should do the trick as well. :)
thanks, Lennert
diff -up linux-3.3.0-1.fc17.x86_64/drivers/gpu/drm/radeon/atombios_crtc.c.orig linux-3.3.0-1.fc17.x86_64/drivers/gpu/drm/radeon/atombios_crtc.c --- linux-3.3.0-1.fc17.x86_64/drivers/gpu/drm/radeon/atombios_crtc.c.orig 2012-03-22 14:52:20.538854547 +0100 +++ linux-3.3.0-1.fc17.x86_64/drivers/gpu/drm/radeon/atombios_crtc.c 2012-03-22 14:55:39.740794113 +0100 @@ -550,8 +550,6 @@ static u32 atombios_adjust_pll(struct dr if (encoder->crtc == crtc) { radeon_encoder = to_radeon_encoder(encoder); connector = radeon_get_connector_for_encoder(encoder); - if (connector && connector->display_info.bpc) - bpc = connector->display_info.bpc; encoder_mode = atombios_get_encoder_mode(encoder); is_duallink = radeon_dig_monitor_is_duallink(encoder, mode->clock); if ((radeon_encoder->devices & (ATOM_DEVICE_LCD_SUPPORT | ATOM_DEVICE_DFP_SUPPORT)) || @@ -922,7 +920,6 @@ static void atombios_crtc_set_pll(struct struct radeon_connector_atom_dig *dig_connector = radeon_connector->con_priv; int dp_clock; - bpc = connector->display_info.bpc;
switch (encoder_mode) { case ATOM_ENCODER_MODE_DP_MST:
From 22ca454eb749968f266d6788a5f4778acc08cc66 Mon Sep 17 00:00:00 2001 From: Alex Deucher alexander.deucher@amd.com Date: Fri, 23 Mar 2012 10:54:45 -0400 Subject: [PATCH] drm/radeon/kms/atom: force bpc to 8 for now
Using the bpc (bits per color) specified by the monitor can cause problems in some cases. Until we get a better handle on how to deal with those cases, just use a bpc of 8.
Reported-by: Lennert Buytenhek buytenh@wantstofly.org Signed-off-by: Alex Deucher alexander.deucher@amd.com Cc: stable@kernel.org
drivers/gpu/drm/radeon/atombios_crtc.c | 8 +++++--- drivers/gpu/drm/radeon/atombios_dp.c | 3 +++ drivers/gpu/drm/radeon/atombios_encoders.c | 4 ++-- 3 files changed, 10 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/radeon/atombios_crtc.c b/drivers/gpu/drm/radeon/atombios_crtc.c index 083b3ea..b5ff1f7 100644 --- a/drivers/gpu/drm/radeon/atombios_crtc.c +++ b/drivers/gpu/drm/radeon/atombios_crtc.c @@ -588,8 +588,8 @@ static u32 atombios_adjust_pll(struct drm_crtc *crtc, if (encoder->crtc == crtc) { radeon_encoder = to_radeon_encoder(encoder); connector = radeon_get_connector_for_encoder(encoder);
if (connector && connector->display_info.bpc)bpc = connector->display_info.bpc;
/* if (connector && connector->display_info.bpc)bpc = connector->display_info.bpc; */ encoder_mode = atombios_get_encoder_mode(encoder); is_duallink = radeon_dig_monitor_is_duallink(encoder, mode->clock); if ((radeon_encoder->devices & (ATOM_DEVICE_LCD_SUPPORT | ATOM_DEVICE_DFP_SUPPORT)) ||@@ -965,7 +965,9 @@ static void atombios_crtc_set_pll(struct drm_crtc *crtc, struct drm_display_mode struct radeon_connector_atom_dig *dig_connector = radeon_connector->con_priv; int dp_clock;
bpc = connector->display_info.bpc;
/* if (connector->display_info.bpc)bpc = connector->display_info.bpc; */switch (encoder_mode) { case ATOM_ENCODER_MODE_DP_MST:
diff --git a/drivers/gpu/drm/radeon/atombios_dp.c b/drivers/gpu/drm/radeon/atombios_dp.c index 6c62be2..c57d856 100644 --- a/drivers/gpu/drm/radeon/atombios_dp.c +++ b/drivers/gpu/drm/radeon/atombios_dp.c @@ -405,10 +405,13 @@ static void dp_get_adjust_train(u8 link_status[DP_LINK_STATUS_SIZE], /* get bpc from the EDID */ static int convert_bpc_to_bpp(int bpc) { +#if 0 if (bpc == 0) return 24; else return bpc * 3; +#endif
- return 24;
}
/* get the max pix clock supported by the link rate and lane num */ diff --git a/drivers/gpu/drm/radeon/atombios_encoders.c b/drivers/gpu/drm/radeon/atombios_encoders.c index 468b874..e607c4d 100644 --- a/drivers/gpu/drm/radeon/atombios_encoders.c +++ b/drivers/gpu/drm/radeon/atombios_encoders.c @@ -541,7 +541,7 @@ atombios_dig_encoder_setup(struct drm_encoder *encoder, int action, int panel_mo dp_clock = dig_connector->dp_clock; dp_lane_count = dig_connector->dp_lane_count; hpd_id = radeon_connector->hpd.hpd;
bpc = connector->display_info.bpc;
/* bpc = connector->display_info.bpc; */}
/* no dig encoder assigned */
@@ -1159,7 +1159,7 @@ atombios_external_encoder_setup(struct drm_encoder *encoder, dp_lane_count = dig_connector->dp_lane_count; connector_object_id = (radeon_connector->connector_object_id & OBJECT_ID_MASK) >> OBJECT_ID_SHIFT;
bpc = connector->display_info.bpc;
/* bpc = connector->display_info.bpc; */}
memset(&args, 0, sizeof(args));
-- 1.7.7.5
On Fri, Mar 23, 2012 at 11:44 AM, Lennert Buytenhek buytenh@wantstofly.org wrote:
On Fri, Mar 23, 2012 at 10:59:27AM -0400, Alex Deucher wrote:
Since Linux 3.0, a system with a Radeon HD 5450 (1002:68f9) connected to a 27" Apple LED cinema display via an Atlona AT-DP400 Dual Link DVI to Mini DisplayPort converter has started to stop giving screen output on switching from text mode to graphical framebuffer during system startup.
I finally had some time to look at this, and it seems to have stopped working after this commit:
commit df271bec805b42527d864777ed035fcbb42e76c0 Author: Alex Deucher alexdeucher@gmail.com Date: Fri May 20 04:34:15 2011 -0400
drm/radeon/kms: properly handle bpc >8 in atom command tables
Signed-off-by: Alex Deucher alexdeucher@gmail.com Signed-off-by: Dave Airlie airlied@redhat.com
...and with the patch below (i.e. reverting part of the commit above) applied to 3.3 I get screen output again.
Even though the monitor seems to have an 8 bit panel, it reports 10 bits per channel in its EDID:
[...] Manufacturer: APP Model 9226 Serial Number 41959462 Made week 38 of 2010 EDID version: 1.4 Digital display 10 bits per primary color channel DisplayPort interface Maximum image size: 60 cm x 34 cm [...]
The (active, dual link) DVI->mDP converter spec sheet says it supports 24 bit color, and I'm guessing that it can't deal with 30. Is the converter at fault here for passing through the EDID unchanged?
Also, what would be the right way to handle this, a kernel command line or module option to limit color depth or something like that? ("Buy a video card with DP output." is a valid answer, I suppose.)
I have no clue at all about graphics, and I have no idea whatsoever what I'm doing here, but I just wanted to post this somewhere for Google to find in case someone else runs into this!
I've inquired with out display team on how to best handle this. In the meantime, it's probably best to just default to 8 bpc. Does the attached patch fix your issue?
I've been using the patch below in a custom Fedora 17 kernel RPM, and that seems to fix the issue. Your patch seems to be a superset of this patch, so logically, your patch should do the trick as well. :)
Can you try the attached patch on top of my previous one?
Alex
thanks, Lennert
diff -up linux-3.3.0-1.fc17.x86_64/drivers/gpu/drm/radeon/atombios_crtc.c.orig linux-3.3.0-1.fc17.x86_64/drivers/gpu/drm/radeon/atombios_crtc.c --- linux-3.3.0-1.fc17.x86_64/drivers/gpu/drm/radeon/atombios_crtc.c.orig 2012-03-22 14:52:20.538854547 +0100 +++ linux-3.3.0-1.fc17.x86_64/drivers/gpu/drm/radeon/atombios_crtc.c 2012-03-22 14:55:39.740794113 +0100 @@ -550,8 +550,6 @@ static u32 atombios_adjust_pll(struct dr if (encoder->crtc == crtc) { radeon_encoder = to_radeon_encoder(encoder); connector = radeon_get_connector_for_encoder(encoder);
- if (connector && connector->display_info.bpc)
- bpc = connector->display_info.bpc;
encoder_mode = atombios_get_encoder_mode(encoder); is_duallink = radeon_dig_monitor_is_duallink(encoder, mode->clock); if ((radeon_encoder->devices & (ATOM_DEVICE_LCD_SUPPORT | ATOM_DEVICE_DFP_SUPPORT)) || @@ -922,7 +920,6 @@ static void atombios_crtc_set_pll(struct struct radeon_connector_atom_dig *dig_connector = radeon_connector->con_priv; int dp_clock;
- bpc = connector->display_info.bpc;
switch (encoder_mode) { case ATOM_ENCODER_MODE_DP_MST:
From 22ca454eb749968f266d6788a5f4778acc08cc66 Mon Sep 17 00:00:00 2001 From: Alex Deucher alexander.deucher@amd.com Date: Fri, 23 Mar 2012 10:54:45 -0400 Subject: [PATCH] drm/radeon/kms/atom: force bpc to 8 for now
Using the bpc (bits per color) specified by the monitor can cause problems in some cases. Until we get a better handle on how to deal with those cases, just use a bpc of 8.
Reported-by: Lennert Buytenhek buytenh@wantstofly.org Signed-off-by: Alex Deucher alexander.deucher@amd.com Cc: stable@kernel.org
drivers/gpu/drm/radeon/atombios_crtc.c | 8 +++++--- drivers/gpu/drm/radeon/atombios_dp.c | 3 +++ drivers/gpu/drm/radeon/atombios_encoders.c | 4 ++-- 3 files changed, 10 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/radeon/atombios_crtc.c b/drivers/gpu/drm/radeon/atombios_crtc.c index 083b3ea..b5ff1f7 100644 --- a/drivers/gpu/drm/radeon/atombios_crtc.c +++ b/drivers/gpu/drm/radeon/atombios_crtc.c @@ -588,8 +588,8 @@ static u32 atombios_adjust_pll(struct drm_crtc *crtc, if (encoder->crtc == crtc) { radeon_encoder = to_radeon_encoder(encoder); connector = radeon_get_connector_for_encoder(encoder);
- if (connector && connector->display_info.bpc)
- bpc = connector->display_info.bpc;
- /* if (connector && connector->display_info.bpc)
- bpc = connector->display_info.bpc; */
encoder_mode = atombios_get_encoder_mode(encoder); is_duallink = radeon_dig_monitor_is_duallink(encoder, mode->clock); if ((radeon_encoder->devices & (ATOM_DEVICE_LCD_SUPPORT | ATOM_DEVICE_DFP_SUPPORT)) || @@ -965,7 +965,9 @@ static void atombios_crtc_set_pll(struct drm_crtc *crtc, struct drm_display_mode struct radeon_connector_atom_dig *dig_connector = radeon_connector->con_priv; int dp_clock;
- bpc = connector->display_info.bpc;
- /* if (connector->display_info.bpc)
- bpc = connector->display_info.bpc; */
switch (encoder_mode) { case ATOM_ENCODER_MODE_DP_MST: diff --git a/drivers/gpu/drm/radeon/atombios_dp.c b/drivers/gpu/drm/radeon/atombios_dp.c index 6c62be2..c57d856 100644 --- a/drivers/gpu/drm/radeon/atombios_dp.c +++ b/drivers/gpu/drm/radeon/atombios_dp.c @@ -405,10 +405,13 @@ static void dp_get_adjust_train(u8 link_status[DP_LINK_STATUS_SIZE], /* get bpc from the EDID */ static int convert_bpc_to_bpp(int bpc) { +#if 0 if (bpc == 0) return 24; else return bpc * 3; +#endif
- return 24;
}
/* get the max pix clock supported by the link rate and lane num */ diff --git a/drivers/gpu/drm/radeon/atombios_encoders.c b/drivers/gpu/drm/radeon/atombios_encoders.c index 468b874..e607c4d 100644 --- a/drivers/gpu/drm/radeon/atombios_encoders.c +++ b/drivers/gpu/drm/radeon/atombios_encoders.c @@ -541,7 +541,7 @@ atombios_dig_encoder_setup(struct drm_encoder *encoder, int action, int panel_mo dp_clock = dig_connector->dp_clock; dp_lane_count = dig_connector->dp_lane_count; hpd_id = radeon_connector->hpd.hpd;
- bpc = connector->display_info.bpc;
- /* bpc = connector->display_info.bpc; */
}
/* no dig encoder assigned */ @@ -1159,7 +1159,7 @@ atombios_external_encoder_setup(struct drm_encoder *encoder, dp_lane_count = dig_connector->dp_lane_count; connector_object_id = (radeon_connector->connector_object_id & OBJECT_ID_MASK) >> OBJECT_ID_SHIFT;
- bpc = connector->display_info.bpc;
- /* bpc = connector->display_info.bpc; */
}
memset(&args, 0, sizeof(args));
1.7.7.5
On Fri, Mar 23, 2012 at 3:34 PM, Alex Deucher alexdeucher@gmail.com wrote:
On Fri, Mar 23, 2012 at 11:44 AM, Lennert Buytenhek buytenh@wantstofly.org wrote:
On Fri, Mar 23, 2012 at 10:59:27AM -0400, Alex Deucher wrote:
Since Linux 3.0, a system with a Radeon HD 5450 (1002:68f9) connected to a 27" Apple LED cinema display via an Atlona AT-DP400 Dual Link DVI to Mini DisplayPort converter has started to stop giving screen output on switching from text mode to graphical framebuffer during system startup.
I finally had some time to look at this, and it seems to have stopped working after this commit:
commit df271bec805b42527d864777ed035fcbb42e76c0 Author: Alex Deucher alexdeucher@gmail.com Date: Fri May 20 04:34:15 2011 -0400
drm/radeon/kms: properly handle bpc >8 in atom command tables
Signed-off-by: Alex Deucher alexdeucher@gmail.com Signed-off-by: Dave Airlie airlied@redhat.com
...and with the patch below (i.e. reverting part of the commit above) applied to 3.3 I get screen output again.
Even though the monitor seems to have an 8 bit panel, it reports 10 bits per channel in its EDID:
[...] Manufacturer: APP Model 9226 Serial Number 41959462 Made week 38 of 2010 EDID version: 1.4 Digital display 10 bits per primary color channel DisplayPort interface Maximum image size: 60 cm x 34 cm [...]
The (active, dual link) DVI->mDP converter spec sheet says it supports 24 bit color, and I'm guessing that it can't deal with 30. Is the converter at fault here for passing through the EDID unchanged?
Also, what would be the right way to handle this, a kernel command line or module option to limit color depth or something like that? ("Buy a video card with DP output." is a valid answer, I suppose.)
I have no clue at all about graphics, and I have no idea whatsoever what I'm doing here, but I just wanted to post this somewhere for Google to find in case someone else runs into this!
I've inquired with out display team on how to best handle this. In the meantime, it's probably best to just default to 8 bpc. Does the attached patch fix your issue?
I've been using the patch below in a custom Fedora 17 kernel RPM, and that seems to fix the issue. Your patch seems to be a superset of this patch, so logically, your patch should do the trick as well. :)
Can you try the attached patch on top of my previous one?
Scratch that. Try this one instead.
Alex
Alex
thanks, Lennert
diff -up linux-3.3.0-1.fc17.x86_64/drivers/gpu/drm/radeon/atombios_crtc.c.orig linux-3.3.0-1.fc17.x86_64/drivers/gpu/drm/radeon/atombios_crtc.c --- linux-3.3.0-1.fc17.x86_64/drivers/gpu/drm/radeon/atombios_crtc.c.orig 2012-03-22 14:52:20.538854547 +0100 +++ linux-3.3.0-1.fc17.x86_64/drivers/gpu/drm/radeon/atombios_crtc.c 2012-03-22 14:55:39.740794113 +0100 @@ -550,8 +550,6 @@ static u32 atombios_adjust_pll(struct dr if (encoder->crtc == crtc) { radeon_encoder = to_radeon_encoder(encoder); connector = radeon_get_connector_for_encoder(encoder);
- if (connector && connector->display_info.bpc)
- bpc = connector->display_info.bpc;
encoder_mode = atombios_get_encoder_mode(encoder); is_duallink = radeon_dig_monitor_is_duallink(encoder, mode->clock); if ((radeon_encoder->devices & (ATOM_DEVICE_LCD_SUPPORT | ATOM_DEVICE_DFP_SUPPORT)) || @@ -922,7 +920,6 @@ static void atombios_crtc_set_pll(struct struct radeon_connector_atom_dig *dig_connector = radeon_connector->con_priv; int dp_clock;
- bpc = connector->display_info.bpc;
switch (encoder_mode) { case ATOM_ENCODER_MODE_DP_MST:
From 22ca454eb749968f266d6788a5f4778acc08cc66 Mon Sep 17 00:00:00 2001 From: Alex Deucher alexander.deucher@amd.com Date: Fri, 23 Mar 2012 10:54:45 -0400 Subject: [PATCH] drm/radeon/kms/atom: force bpc to 8 for now
Using the bpc (bits per color) specified by the monitor can cause problems in some cases. Until we get a better handle on how to deal with those cases, just use a bpc of 8.
Reported-by: Lennert Buytenhek buytenh@wantstofly.org Signed-off-by: Alex Deucher alexander.deucher@amd.com Cc: stable@kernel.org
drivers/gpu/drm/radeon/atombios_crtc.c | 8 +++++--- drivers/gpu/drm/radeon/atombios_dp.c | 3 +++ drivers/gpu/drm/radeon/atombios_encoders.c | 4 ++-- 3 files changed, 10 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/radeon/atombios_crtc.c b/drivers/gpu/drm/radeon/atombios_crtc.c index 083b3ea..b5ff1f7 100644 --- a/drivers/gpu/drm/radeon/atombios_crtc.c +++ b/drivers/gpu/drm/radeon/atombios_crtc.c @@ -588,8 +588,8 @@ static u32 atombios_adjust_pll(struct drm_crtc *crtc, if (encoder->crtc == crtc) { radeon_encoder = to_radeon_encoder(encoder); connector = radeon_get_connector_for_encoder(encoder);
- if (connector && connector->display_info.bpc)
- bpc = connector->display_info.bpc;
- /* if (connector && connector->display_info.bpc)
- bpc = connector->display_info.bpc; */
encoder_mode = atombios_get_encoder_mode(encoder); is_duallink = radeon_dig_monitor_is_duallink(encoder, mode->clock); if ((radeon_encoder->devices & (ATOM_DEVICE_LCD_SUPPORT | ATOM_DEVICE_DFP_SUPPORT)) || @@ -965,7 +965,9 @@ static void atombios_crtc_set_pll(struct drm_crtc *crtc, struct drm_display_mode struct radeon_connector_atom_dig *dig_connector = radeon_connector->con_priv; int dp_clock;
- bpc = connector->display_info.bpc;
- /* if (connector->display_info.bpc)
- bpc = connector->display_info.bpc; */
switch (encoder_mode) { case ATOM_ENCODER_MODE_DP_MST: diff --git a/drivers/gpu/drm/radeon/atombios_dp.c b/drivers/gpu/drm/radeon/atombios_dp.c index 6c62be2..c57d856 100644 --- a/drivers/gpu/drm/radeon/atombios_dp.c +++ b/drivers/gpu/drm/radeon/atombios_dp.c @@ -405,10 +405,13 @@ static void dp_get_adjust_train(u8 link_status[DP_LINK_STATUS_SIZE], /* get bpc from the EDID */ static int convert_bpc_to_bpp(int bpc) { +#if 0 if (bpc == 0) return 24; else return bpc * 3; +#endif
- return 24;
}
/* get the max pix clock supported by the link rate and lane num */ diff --git a/drivers/gpu/drm/radeon/atombios_encoders.c b/drivers/gpu/drm/radeon/atombios_encoders.c index 468b874..e607c4d 100644 --- a/drivers/gpu/drm/radeon/atombios_encoders.c +++ b/drivers/gpu/drm/radeon/atombios_encoders.c @@ -541,7 +541,7 @@ atombios_dig_encoder_setup(struct drm_encoder *encoder, int action, int panel_mo dp_clock = dig_connector->dp_clock; dp_lane_count = dig_connector->dp_lane_count; hpd_id = radeon_connector->hpd.hpd;
- bpc = connector->display_info.bpc;
- /* bpc = connector->display_info.bpc; */
}
/* no dig encoder assigned */ @@ -1159,7 +1159,7 @@ atombios_external_encoder_setup(struct drm_encoder *encoder, dp_lane_count = dig_connector->dp_lane_count; connector_object_id = (radeon_connector->connector_object_id & OBJECT_ID_MASK) >> OBJECT_ID_SHIFT;
- bpc = connector->display_info.bpc;
- /* bpc = connector->display_info.bpc; */
}
memset(&args, 0, sizeof(args));
1.7.7.5
On Fri, Mar 23, 2012 at 03:42:44PM -0400, Alex Deucher wrote:
Since Linux 3.0, a system with a Radeon HD 5450 (1002:68f9) connected to a 27" Apple LED cinema display via an Atlona AT-DP400 Dual Link DVI to Mini DisplayPort converter has started to stop giving screen output on switching from text mode to graphical framebuffer during system startup.
I finally had some time to look at this, and it seems to have stopped working after this commit:
commit df271bec805b42527d864777ed035fcbb42e76c0 Author: Alex Deucher alexdeucher@gmail.com Date: Fri May 20 04:34:15 2011 -0400
drm/radeon/kms: properly handle bpc >8 in atom command tables
Signed-off-by: Alex Deucher alexdeucher@gmail.com Signed-off-by: Dave Airlie airlied@redhat.com
...and with the patch below (i.e. reverting part of the commit above) applied to 3.3 I get screen output again.
Even though the monitor seems to have an 8 bit panel, it reports 10 bits per channel in its EDID:
[...] Manufacturer: APP Model 9226 Serial Number 41959462 Made week 38 of 2010 EDID version: 1.4 Digital display 10 bits per primary color channel DisplayPort interface Maximum image size: 60 cm x 34 cm [...]
The (active, dual link) DVI->mDP converter spec sheet says it supports 24 bit color, and I'm guessing that it can't deal with 30. Is the converter at fault here for passing through the EDID unchanged?
Also, what would be the right way to handle this, a kernel command line or module option to limit color depth or something like that? ("Buy a video card with DP output." is a valid answer, I suppose.)
I have no clue at all about graphics, and I have no idea whatsoever what I'm doing here, but I just wanted to post this somewhere for Google to find in case someone else runs into this!
I've inquired with out display team on how to best handle this. In the meantime, it's probably best to just default to 8 bpc. Does the attached patch fix your issue?
I've been using the patch below in a custom Fedora 17 kernel RPM, and that seems to fix the issue. Your patch seems to be a superset of this patch, so logically, your patch should do the trick as well. :)
Can you try the attached patch on top of my previous one?
Scratch that. Try this one instead.
The 3.3 + 0001-drm-radeon-kms-atom-force-bpc-to-8-for-now.patch + 0001-drm-radeon-kms-improve-bpc-handling-v2.patch combo seems to work fine -- I get display output as expected.
Tested-by: Lennert Buytenhek buytenh@wantstofly.org
thanks, Lennert
dri-devel@lists.freedesktop.org
-
Alex Deucher -
Lennert Buytenhek