[PATCH 0/1] Use amdgpu by default on SI dGPUs

[PATCH 0/1] Use amdgpu by default on SI dGPUs

[Timur Kristóf]

Based on my earlier series:
"Use amdgpu by default on CIK dGPUs"

Now that the DC analog connector support and VCE1 support
landed, SI dGPUs are at feature parity with the old
radeon driver too.

Why?

Compared to the old radeon driver, amdgpu offers better
performance, more display features through DC,
as well as support for Vulkan 1.3 through RADV.

What can these GPUs actually do on amdgpu?

Tahiti and Pitcairn can play some modern games, albeit
at lower resolutions and lower frame rates. They are
mainly held back by a low amount of VRAM (2~3 GiB).
The other SI "gaming" GPUs are mainly useful for
playing games from their era (the mid-2010s)
or less demanding games in general.

As a reminder, SI dedicated GPUs are the following:
Tahiti (2012~2014):
  Radeon HD 7870 XT, 7950, 7970, 7990, 8950, 8970, 8990
  Radeon R9 280 series
  FirePro W8000, W9000, D500, D700, S9000, S9050, S10000
  Radeon Sky 700, 900
Pitcairn (2012~2015):
  Radeon HD 7850, 7870, 7970M, 8870, 8970M
  Radeon R9 265, 270/370 series, M290X, M390
  FirePro W5000, W7000, D300, R5000, S7000
Cape Verde (2012~2016):
  Radeon HD 7730, 7750, 7770, 8730, 8760
  Radeon R7 250E, 250X, 350, 450
  FirePro W600, W4100, M4000, M6000
Oland (2013~2019):
  Radeon HD 8570, 8670
  Radeon R5 240, 250, 330, 340, 350, 430, 520, 610
  FirePro W2100
Hainan (2013~2016):
  various mobile GPUs

Timur Kristóf (1):
  drm/amdgpu: Use amdgpu by default on SI dedicated GPUs

 drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 1 +
 drivers/gpu/drm/radeon/radeon_drv.c     | 1 +
 2 files changed, 2 insertions(+)

-- 
2.51.1

[PATCH 1/1] drm/amdgpu: Use amdgpu by default on SI dedicated GPUs

[Timur Kristóf]

Now that the DC analog connector support and VCE1 support landed,
SI dGPUs are at feature parity with the old radeon driver.

Enabling the amdgpu driver by default for SI dGPUs has the
following benefits:

- More stable OpenGL support through RadeonSI
- Vulkan support through RADV
- Improved performance
- Better display features through DC

Users who want to keep using the old driver can do so using:
amdgpu.si_support=0 radeon.si_support=1

Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 1 +
 drivers/gpu/drm/radeon/radeon_drv.c     | 1 +
 2 files changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
index 3cf36d28d27f..0539f97fa2f5 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
@@ -2327,6 +2327,7 @@ static bool amdgpu_support_enabled(struct device *dev,
 		param = "si_support";
 		module_param = amdgpu_si_support;
 		amdgpu_support_built = IS_ENABLED(CONFIG_DRM_AMDGPU_SI);
+		support_by_default = true;
 		break;
 
 	case CHIP_BONAIRE:
diff --git a/drivers/gpu/drm/radeon/radeon_drv.c b/drivers/gpu/drm/radeon/radeon_drv.c
index 40dff6feac8a..fe7ed70f4703 100644
--- a/drivers/gpu/drm/radeon/radeon_drv.c
+++ b/drivers/gpu/drm/radeon/radeon_drv.c
@@ -273,6 +273,7 @@ static bool radeon_support_enabled(struct device *dev,
 		gen = "SI";
 		module_param = radeon_si_support;
 		amdgpu_support_built &= IS_ENABLED(CONFIG_DRM_AMDGPU_SI);
+		support_by_default = false;
 		break;
 
 	case CHIP_BONAIRE:
-- 
2.51.1

Re: [PATCH 1/1] drm/amdgpu: Use amdgpu by default on SI dedicated GPUs

[Christian König]

On 11/13/25 20:07, Timur Kristóf wrote:
> Now that the DC analog connector support and VCE1 support landed,
> SI dGPUs are at feature parity with the old radeon driver.
> 
> Enabling the amdgpu driver by default for SI dGPUs has the
> following benefits:
> 
> - More stable OpenGL support through RadeonSI
> - Vulkan support through RADV
> - Improved performance
> - Better display features through DC
> 
> Users who want to keep using the old driver can do so using:
> amdgpu.si_support=0 radeon.si_support=1
> 
> Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>

The patch should probably also update the text in the Kconfig file drivers/gpu/drm/amd/amdgpu/Kconfig.

That currently reads:

config DRM_AMDGPU_SI
        bool "Enable amdgpu support for SI parts"
        depends on DRM_AMDGPU
        help
          Choose this option if you want to enable experimental support
          for SI (Southern Islands) asics.

          SI is already supported in radeon. Experimental support for SI
          in amdgpu will be disabled by default and is still provided by
          radeon. Use module options to override this:

          radeon.si_support=0 amdgpu.si_support=1

Same for CIK BTW.

Apart from that look good to me,
Christian.

> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 1 +
>  drivers/gpu/drm/radeon/radeon_drv.c     | 1 +
>  2 files changed, 2 insertions(+)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> index 3cf36d28d27f..0539f97fa2f5 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> @@ -2327,6 +2327,7 @@ static bool amdgpu_support_enabled(struct device *dev,
>  		param = "si_support";
>  		module_param = amdgpu_si_support;
>  		amdgpu_support_built = IS_ENABLED(CONFIG_DRM_AMDGPU_SI);
> +		support_by_default = true;
>  		break;
>  
>  	case CHIP_BONAIRE:
> diff --git a/drivers/gpu/drm/radeon/radeon_drv.c b/drivers/gpu/drm/radeon/radeon_drv.c
> index 40dff6feac8a..fe7ed70f4703 100644
> --- a/drivers/gpu/drm/radeon/radeon_drv.c
> +++ b/drivers/gpu/drm/radeon/radeon_drv.c
> @@ -273,6 +273,7 @@ static bool radeon_support_enabled(struct device *dev,
>  		gen = "SI";
>  		module_param = radeon_si_support;
>  		amdgpu_support_built &= IS_ENABLED(CONFIG_DRM_AMDGPU_SI);
> +		support_by_default = false;
>  		break;
>  
>  	case CHIP_BONAIRE:

Re: [PATCH 1/1] drm/amdgpu: Use amdgpu by default on SI dedicated GPUs

[Timur Kristóf]

On Fri, 2025-11-14 at 11:40 +0100, Christian König wrote:
> On 11/13/25 20:07, Timur Kristóf wrote:
> > Now that the DC analog connector support and VCE1 support landed,
> > SI dGPUs are at feature parity with the old radeon driver.
> > 
> > Enabling the amdgpu driver by default for SI dGPUs has the
> > following benefits:
> > 
> > - More stable OpenGL support through RadeonSI
> > - Vulkan support through RADV
> > - Improved performance
> > - Better display features through DC
> > 
> > Users who want to keep using the old driver can do so using:
> > amdgpu.si_support=0 radeon.si_support=1
> > 
> > Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
> 
> The patch should probably also update the text in the Kconfig file
> drivers/gpu/drm/amd/amdgpu/Kconfig.

Nice catch.

I will send a second version for both SI and CIK to update the Konfig
file as well.

> 
> That currently reads:
> 
> config DRM_AMDGPU_SI
>         bool "Enable amdgpu support for SI parts"
>         depends on DRM_AMDGPU
>         help
>           Choose this option if you want to enable experimental
> support
>           for SI (Southern Islands) asics.
> 
>           SI is already supported in radeon. Experimental support for
> SI
>           in amdgpu will be disabled by default and is still provided
> by
>           radeon. Use module options to override this:
> 
>           radeon.si_support=0 amdgpu.si_support=1
> 
> Same for CIK BTW.
> 
> Apart from that look good to me,
> Christian.
> 
> > ---
> >  drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 1 +
> >  drivers/gpu/drm/radeon/radeon_drv.c     | 1 +
> >  2 files changed, 2 insertions(+)
> > 
> > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> > b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> > index 3cf36d28d27f..0539f97fa2f5 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> > @@ -2327,6 +2327,7 @@ static bool amdgpu_support_enabled(struct
> > device *dev,
> >  		param = "si_support";
> >  		module_param = amdgpu_si_support;
> >  		amdgpu_support_built =
> > IS_ENABLED(CONFIG_DRM_AMDGPU_SI);
> > +		support_by_default = true;
> >  		break;
> >  
> >  	case CHIP_BONAIRE:
> > diff --git a/drivers/gpu/drm/radeon/radeon_drv.c
> > b/drivers/gpu/drm/radeon/radeon_drv.c
> > index 40dff6feac8a..fe7ed70f4703 100644
> > --- a/drivers/gpu/drm/radeon/radeon_drv.c
> > +++ b/drivers/gpu/drm/radeon/radeon_drv.c
> > @@ -273,6 +273,7 @@ static bool radeon_support_enabled(struct
> > device *dev,
> >  		gen = "SI";
> >  		module_param = radeon_si_support;
> >  		amdgpu_support_built &=
> > IS_ENABLED(CONFIG_DRM_AMDGPU_SI);
> > +		support_by_default = false;
> >  		break;
> >  
> >  	case CHIP_BONAIRE: