[AMD Official Use Only] Hi Chandan, This issue we found on the Zork project which uses the kernel 5.4 on. So I just implemented it on kernel 5.4. For finding out which is 3250c, I referenced the function which is implemented from another function. Below is the part where I found it. drivers/gpu/drm/amd/amdgpu/amdgpu_device.c- case CHIP_RAVEN: if (adev->rev_id >= 8) chip_name = "raven2"; else if (adev->pdev->device == 0x15d8) chip_name = "picasso"; else chip_name = "raven"; break; BR, Ryan Lin. -----Original Message----- From: VURDIGERENATARAJ, CHANDAN <CHANDAN.VURDIGERENATARAJ@xxxxxxx> Sent: Wednesday, March 30, 2022 12:30 PM To: Lin, Tsung-hua (Ryan) <Tsung-hua.Lin@xxxxxxx> Cc: David (ChunMing) Zhou <David1.Zhou@xxxxxxx>; Drew Davenport <ddavenport@xxxxxxxxxxxx>; Li, Sun peng (Leo) <Sunpeng.Li@xxxxxxx>; Li, Leon <Leon.Li@xxxxxxx>; dri-devel@xxxxxxxxxxxxxxxxxxxxx; Siqueira, Rodrigo <Rodrigo.Siqueira@xxxxxxx>; linux-kernel@xxxxxxxxxxxxxxx; amd-gfx@xxxxxxxxxxxxxxxxxxxxx; Koenig, Christian <Christian.Koenig@xxxxxxx>; David Airlie <airlied@xxxxxxxx>; Sean Paul <seanpaul@xxxxxxxxxxxx>; Louis Li <ching-shih.li@xxxxxxxxxxxxxxxxxxxxxxxxxxx>; Daniel Vetter <daniel@xxxxxxxx>; Bas Nieuwenhuizen <bas@xxxxxxxxxxxxxxxxxxx>; Deucher, Alexander <Alexander.Deucher@xxxxxxx>; Stéphane Marchesin <marcheu@xxxxxxxxxxxx>; Kazlauskas, Nicholas <Nicholas.Kazlauskas@xxxxxxx>; Wentland, Harry <Harry.Wentland@xxxxxxx>; Lin, Tsung-hua (Ryan) <Tsung-hua.Lin@xxxxxxx>; Mark Yacoub <markyacoub@xxxxxxxxxx> Subject: RE: [PATCH v2] drm/amdgpu: fix that issue that the number of the crtc of the 3250c is not correct Hi Ryan, Is this change applicable on a specific kernel version? On latest I see IP DISCOVERY based impl for CHIP_RAVEN. >[Why] >External displays take priority over internal display when there are fewer display controllers than displays. > > [How] >The root cause is because of that number of the crtc is not correct. >The number of the crtc on the 3250c is 3, but on the 3500c is 4. >On the source code, we can see that number of the crtc has been fixed at 4. >Needs to set the num_crtc to 3 for 3250c platform. > >v2: > - remove unnecessary comments and Id > >Signed-off-by: Ryan Lin <tsung-hua.lin@xxxxxxx> > >--- > drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 12 +++++++++--- > 1 file changed, 9 insertions(+), 3 deletions(-) > >diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c >index 40c91b448f7da..455a2c45e8cda 100644 >--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c >+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c >@@ -2738,9 +2738,15 @@ static int dm_early_init(void *handle) > break; > #if defined(CONFIG_DRM_AMD_DC_DCN1_0) > case CHIP_RAVEN: >- adev->mode_info.num_crtc = 4; >- adev->mode_info.num_hpd = 4; >- adev->mode_info.num_dig = 4; >+ if (adev->rev_id >= 8) { May I know what this ">=8" indicate? Also, should it be external_rev_id if its based on old version? >+ adev->mode_info.num_crtc = 3; >+ adev->mode_info.num_hpd = 3; >+ adev->mode_info.num_dig = 3; >+ } else { >+ adev->mode_info.num_crtc = 4; >+ adev->mode_info.num_hpd = 4; >+ adev->mode_info.num_dig = 4; >+ } > break; > #endif > #if defined(CONFIG_DRM_AMD_DC_DCN2_0) >-- >2.25.1 > BR, Chandan V N