Re: [PATCH] drm/nouveau/pci: rework AGP dependency

2021-02-25 Thread Daniel Vetter 
On Thu, Feb 25, 2021 at 1:59 PM Christian König
 wrote:
>
> Am 25.02.21 um 13:52 schrieb Arnd Bergmann:
> > From: Arnd Bergmann 
> >
> > I noticed a warning from 'nm' when CONFIG_TRIM_UNUSED_KSYMS is set
> > and IS_REACHABLE(CONFIG_AGP) is false:
> >
> > drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.o: no symbols
> >
> > I later found this is completely harmless and we should find a way
> > to suppress the warning, but at that point I had already done a
> > cleanup patch to address this instance.
> >
> > It turns out this code could be improved anyway, as the current version
> > behaves unexpectedly when AGP is a loadable module but nouveau is built-in
> > itself, in which case it silently omits agp support.
> >
> > A better way to handle this is with a Kconfig dependency that requires
> > AGP either to be disabled, or forces nouveau to be a module for AGP=m.
> > With this change, the compile-time hack can be removed and lld no
> > longer warns.
> >
> > Fixes: 340b0e7c500a ("drm/nouveau/pci: merge agp handling from nouveau drm")
> > Signed-off-by: Arnd Bergmann 
> > ---
> >   drivers/gpu/drm/nouveau/Kbuild | 1 +
> >   drivers/gpu/drm/nouveau/Kconfig| 1 +
> >   drivers/gpu/drm/nouveau/nvkm/subdev/pci/Kbuild | 2 +-
> >   drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.c  | 2 --
> >   drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.h  | 9 +
> >   5 files changed, 8 insertions(+), 7 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/nouveau/Kbuild b/drivers/gpu/drm/nouveau/Kbuild
> > index 60586fb8275e..173b8d9d85e3 100644
> > --- a/drivers/gpu/drm/nouveau/Kbuild
> > +++ b/drivers/gpu/drm/nouveau/Kbuild
> > @@ -15,6 +15,7 @@ nouveau-y := $(nvif-y)
> >   #- code also used by various userspace tools/tests
> >   include $(src)/nvkm/Kbuild
> >   nouveau-y += $(nvkm-y)
> > +nouveau-m += $(nvkm-m)
> >
> >   # DRM - general
> >   ifdef CONFIG_X86
> > diff --git a/drivers/gpu/drm/nouveau/Kconfig 
> > b/drivers/gpu/drm/nouveau/Kconfig
> > index 278e048235a9..90276a557a70 100644
> > --- a/drivers/gpu/drm/nouveau/Kconfig
> > +++ b/drivers/gpu/drm/nouveau/Kconfig
> > @@ -2,6 +2,7 @@
> >   config DRM_NOUVEAU
> >   tristate "Nouveau (NVIDIA) cards"
> >   depends on DRM && PCI && MMU
> > + depends on AGP || !AGP
>
> My first thought was WTF? But then I realized that this totally makes sense.

depends on SYM || !SYM

is essentially

optional depends on SYM

when SYM is a tri-state. I think there was even patches to kconfig to
add something like that since it's such a common pattern. Might be
neat to resurrect that for more clarity.
-Daniel

> We should probably have the same for radeon as well.
>
> Apart from that the patch is Acked-by: Christian König
> 
>
> >   select IOMMU_API
> >   select FW_LOADER
> >   select DRM_KMS_HELPER
> > diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/pci/Kbuild 
> > b/drivers/gpu/drm/nouveau/nvkm/subdev/pci/Kbuild
> > index 174bdf995271..a400c680cf65 100644
> > --- a/drivers/gpu/drm/nouveau/nvkm/subdev/pci/Kbuild
> > +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/pci/Kbuild
> > @@ -1,5 +1,5 @@
> >   # SPDX-License-Identifier: MIT
> > -nvkm-y += nvkm/subdev/pci/agp.o
> > +nvkm-$(CONFIG_AGP) += nvkm/subdev/pci/agp.o
> >   nvkm-y += nvkm/subdev/pci/base.o
> >   nvkm-y += nvkm/subdev/pci/pcie.o
> >   nvkm-y += nvkm/subdev/pci/nv04.o
> > diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.c 
> > b/drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.c
> > index 385a90f91ed6..86c9e1d658af 100644
> > --- a/drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.c
> > +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.c
> > @@ -20,7 +20,6 @@
> >* OTHER DEALINGS IN THE SOFTWARE.
> >*/
> >   #include "agp.h"
> > -#ifdef __NVKM_PCI_AGP_H__
> >   #include 
> >
> >   struct nvkm_device_agp_quirk {
> > @@ -172,4 +171,3 @@ nvkm_agp_ctor(struct nvkm_pci *pci)
> >
> >   pci->agp.mtrr = arch_phys_wc_add(pci->agp.base, pci->agp.size);
> >   }
> > -#endif
> > diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.h 
> > b/drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.h
> > index ad4d3621d02b..041fe1fbf093 100644
> > --- a/drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.h
> > +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.h
> > @@ -1,15 +1,14 @@
> > -/* SPDX-License-Identifier: MIT */
> > -#include "priv.h"
> > -#if defined(CONFIG_AGP) || (defined(CONFIG_AGP_MODULE) && defined(MODULE))
> >   #ifndef __NVKM_PCI_AGP_H__
> >   #define __NVKM_PCI_AGP_H__
> >
> > +/* SPDX-License-Identifier: MIT */
> > +#include "priv.h"
> > +#if IS_ENABLED(CONFIG_AGP)
> >   void nvkm_agp_ctor(struct nvkm_pci *);
> >   void nvkm_agp_dtor(struct nvkm_pci *);
> >   void nvkm_agp_preinit(struct nvkm_pci *);
> >   int nvkm_agp_init(struct nvkm_pci *);
> >   void nvkm_agp_fini(struct nvkm_pci *);
> > -#endif
> >   #else
> >   static inline void nvkm_agp_ctor(struct nvkm_pci *pci) {}
> >   static inline void nvkm_agp_dtor(struct nvkm_pci *pci) {}
> > @@ -17,3 +16,5 @@ static inline void

Re: [PATCH] drm/nouveau/pci: rework AGP dependency

2021-02-25 Thread Christian König 

Am 25.02.21 um 13:52 schrieb Arnd Bergmann:

From: Arnd Bergmann 

I noticed a warning from 'nm' when CONFIG_TRIM_UNUSED_KSYMS is set
and IS_REACHABLE(CONFIG_AGP) is false:

drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.o: no symbols

I later found this is completely harmless and we should find a way
to suppress the warning, but at that point I had already done a
cleanup patch to address this instance.

It turns out this code could be improved anyway, as the current version
behaves unexpectedly when AGP is a loadable module but nouveau is built-in
itself, in which case it silently omits agp support.

A better way to handle this is with a Kconfig dependency that requires
AGP either to be disabled, or forces nouveau to be a module for AGP=m.
With this change, the compile-time hack can be removed and lld no
longer warns.

Fixes: 340b0e7c500a ("drm/nouveau/pci: merge agp handling from nouveau drm")
Signed-off-by: Arnd Bergmann 
---
  drivers/gpu/drm/nouveau/Kbuild | 1 +
  drivers/gpu/drm/nouveau/Kconfig| 1 +
  drivers/gpu/drm/nouveau/nvkm/subdev/pci/Kbuild | 2 +-
  drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.c  | 2 --
  drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.h  | 9 +
  5 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/Kbuild b/drivers/gpu/drm/nouveau/Kbuild
index 60586fb8275e..173b8d9d85e3 100644
--- a/drivers/gpu/drm/nouveau/Kbuild
+++ b/drivers/gpu/drm/nouveau/Kbuild
@@ -15,6 +15,7 @@ nouveau-y := $(nvif-y)
  #- code also used by various userspace tools/tests
  include $(src)/nvkm/Kbuild
  nouveau-y += $(nvkm-y)
+nouveau-m += $(nvkm-m)
  
  # DRM - general

  ifdef CONFIG_X86
diff --git a/drivers/gpu/drm/nouveau/Kconfig b/drivers/gpu/drm/nouveau/Kconfig
index 278e048235a9..90276a557a70 100644
--- a/drivers/gpu/drm/nouveau/Kconfig
+++ b/drivers/gpu/drm/nouveau/Kconfig
@@ -2,6 +2,7 @@
  config DRM_NOUVEAU
tristate "Nouveau (NVIDIA) cards"
depends on DRM && PCI && MMU
+   depends on AGP || !AGP


My first thought was WTF? But then I realized that this totally makes sense.

We should probably have the same for radeon as well.

Apart from that the patch is Acked-by: Christian König 




select IOMMU_API
select FW_LOADER
select DRM_KMS_HELPER
diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/pci/Kbuild 
b/drivers/gpu/drm/nouveau/nvkm/subdev/pci/Kbuild
index 174bdf995271..a400c680cf65 100644
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/pci/Kbuild
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/pci/Kbuild
@@ -1,5 +1,5 @@
  # SPDX-License-Identifier: MIT
-nvkm-y += nvkm/subdev/pci/agp.o
+nvkm-$(CONFIG_AGP) += nvkm/subdev/pci/agp.o
  nvkm-y += nvkm/subdev/pci/base.o
  nvkm-y += nvkm/subdev/pci/pcie.o
  nvkm-y += nvkm/subdev/pci/nv04.o
diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.c 
b/drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.c
index 385a90f91ed6..86c9e1d658af 100644
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.c
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.c
@@ -20,7 +20,6 @@
   * OTHER DEALINGS IN THE SOFTWARE.
   */
  #include "agp.h"
-#ifdef __NVKM_PCI_AGP_H__
  #include 
  
  struct nvkm_device_agp_quirk {

@@ -172,4 +171,3 @@ nvkm_agp_ctor(struct nvkm_pci *pci)
  
  	pci->agp.mtrr = arch_phys_wc_add(pci->agp.base, pci->agp.size);

  }
-#endif
diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.h 
b/drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.h
index ad4d3621d02b..041fe1fbf093 100644
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.h
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.h
@@ -1,15 +1,14 @@
-/* SPDX-License-Identifier: MIT */
-#include "priv.h"
-#if defined(CONFIG_AGP) || (defined(CONFIG_AGP_MODULE) && defined(MODULE))
  #ifndef __NVKM_PCI_AGP_H__
  #define __NVKM_PCI_AGP_H__
  
+/* SPDX-License-Identifier: MIT */

+#include "priv.h"
+#if IS_ENABLED(CONFIG_AGP)
  void nvkm_agp_ctor(struct nvkm_pci *);
  void nvkm_agp_dtor(struct nvkm_pci *);
  void nvkm_agp_preinit(struct nvkm_pci *);
  int nvkm_agp_init(struct nvkm_pci *);
  void nvkm_agp_fini(struct nvkm_pci *);
-#endif
  #else
  static inline void nvkm_agp_ctor(struct nvkm_pci *pci) {}
  static inline void nvkm_agp_dtor(struct nvkm_pci *pci) {}
@@ -17,3 +16,5 @@ static inline void nvkm_agp_preinit(struct nvkm_pci *pci) {}
  static inline int nvkm_agp_init(struct nvkm_pci *pci) { return -ENOSYS; }
  static inline void nvkm_agp_fini(struct nvkm_pci *pci) {}
  #endif
+
+#endif

[PATCH] drm/nouveau/pci: rework AGP dependency

2021-02-25 Thread Arnd Bergmann 
From: Arnd Bergmann 

I noticed a warning from 'nm' when CONFIG_TRIM_UNUSED_KSYMS is set
and IS_REACHABLE(CONFIG_AGP) is false:

drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.o: no symbols

I later found this is completely harmless and we should find a way
to suppress the warning, but at that point I had already done a
cleanup patch to address this instance.

It turns out this code could be improved anyway, as the current version
behaves unexpectedly when AGP is a loadable module but nouveau is built-in
itself, in which case it silently omits agp support.

A better way to handle this is with a Kconfig dependency that requires
AGP either to be disabled, or forces nouveau to be a module for AGP=m.
With this change, the compile-time hack can be removed and lld no
longer warns.

Fixes: 340b0e7c500a ("drm/nouveau/pci: merge agp handling from nouveau drm")
Signed-off-by: Arnd Bergmann 
---
 drivers/gpu/drm/nouveau/Kbuild | 1 +
 drivers/gpu/drm/nouveau/Kconfig| 1 +
 drivers/gpu/drm/nouveau/nvkm/subdev/pci/Kbuild | 2 +-
 drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.c  | 2 --
 drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.h  | 9 +
 5 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/Kbuild b/drivers/gpu/drm/nouveau/Kbuild
index 60586fb8275e..173b8d9d85e3 100644
--- a/drivers/gpu/drm/nouveau/Kbuild
+++ b/drivers/gpu/drm/nouveau/Kbuild
@@ -15,6 +15,7 @@ nouveau-y := $(nvif-y)
 #- code also used by various userspace tools/tests
 include $(src)/nvkm/Kbuild
 nouveau-y += $(nvkm-y)
+nouveau-m += $(nvkm-m)
 
 # DRM - general
 ifdef CONFIG_X86
diff --git a/drivers/gpu/drm/nouveau/Kconfig b/drivers/gpu/drm/nouveau/Kconfig
index 278e048235a9..90276a557a70 100644
--- a/drivers/gpu/drm/nouveau/Kconfig
+++ b/drivers/gpu/drm/nouveau/Kconfig
@@ -2,6 +2,7 @@
 config DRM_NOUVEAU
tristate "Nouveau (NVIDIA) cards"
depends on DRM && PCI && MMU
+   depends on AGP || !AGP
select IOMMU_API
select FW_LOADER
select DRM_KMS_HELPER
diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/pci/Kbuild 
b/drivers/gpu/drm/nouveau/nvkm/subdev/pci/Kbuild
index 174bdf995271..a400c680cf65 100644
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/pci/Kbuild
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/pci/Kbuild
@@ -1,5 +1,5 @@
 # SPDX-License-Identifier: MIT
-nvkm-y += nvkm/subdev/pci/agp.o
+nvkm-$(CONFIG_AGP) += nvkm/subdev/pci/agp.o
 nvkm-y += nvkm/subdev/pci/base.o
 nvkm-y += nvkm/subdev/pci/pcie.o
 nvkm-y += nvkm/subdev/pci/nv04.o
diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.c 
b/drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.c
index 385a90f91ed6..86c9e1d658af 100644
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.c
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.c
@@ -20,7 +20,6 @@
  * OTHER DEALINGS IN THE SOFTWARE.
  */
 #include "agp.h"
-#ifdef __NVKM_PCI_AGP_H__
 #include 
 
 struct nvkm_device_agp_quirk {
@@ -172,4 +171,3 @@ nvkm_agp_ctor(struct nvkm_pci *pci)
 
pci->agp.mtrr = arch_phys_wc_add(pci->agp.base, pci->agp.size);
 }
-#endif
diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.h 
b/drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.h
index ad4d3621d02b..041fe1fbf093 100644
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.h
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/pci/agp.h
@@ -1,15 +1,14 @@
-/* SPDX-License-Identifier: MIT */
-#include "priv.h"
-#if defined(CONFIG_AGP) || (defined(CONFIG_AGP_MODULE) && defined(MODULE))
 #ifndef __NVKM_PCI_AGP_H__
 #define __NVKM_PCI_AGP_H__
 
+/* SPDX-License-Identifier: MIT */
+#include "priv.h"
+#if IS_ENABLED(CONFIG_AGP)
 void nvkm_agp_ctor(struct nvkm_pci *);
 void nvkm_agp_dtor(struct nvkm_pci *);
 void nvkm_agp_preinit(struct nvkm_pci *);
 int nvkm_agp_init(struct nvkm_pci *);
 void nvkm_agp_fini(struct nvkm_pci *);
-#endif
 #else
 static inline void nvkm_agp_ctor(struct nvkm_pci *pci) {}
 static inline void nvkm_agp_dtor(struct nvkm_pci *pci) {}
@@ -17,3 +16,5 @@ static inline void nvkm_agp_preinit(struct nvkm_pci *pci) {}
 static inline int nvkm_agp_init(struct nvkm_pci *pci) { return -ENOSYS; }
 static inline void nvkm_agp_fini(struct nvkm_pci *pci) {}
 #endif
+
+#endif
-- 
2.29.2