Arnd Bergmann
2021-Feb-25  12:52 UTC
[Nouveau] [PATCH] drm/nouveau/pci: rework AGP dependency
From: Arnd Bergmann <arnd at arndb.de>
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 <arnd at arndb.de>
---
 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 <core/option.h>
 
 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
Christian König
2021-Feb-25  12:59 UTC
[Nouveau] [PATCH] drm/nouveau/pci: rework AGP dependency
Am 25.02.21 um 13:52 schrieb Arnd Bergmann:> From: Arnd Bergmann <arnd at arndb.de> > > 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 <arnd at arndb.de> > --- > 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 += $(nvkm-m) > > # DRM - general > ifdef CONFIG_X86 > diff --git a/drivers/gpu/drm/nouveau/Kconfig b/drivers/gpu/drm/nouveau/Kconfig > index 278e048235a9..90276a557a70 100644 > --- a/drivers/gpu/drm/nouveau/Kconfig > +++ b/drivers/gpu/drm/nouveau/Kconfig > @@ -2,6 +2,7 @@ > config DRM_NOUVEAU > tristate "Nouveau (NVIDIA) cards" > depends on DRM && PCI && MMU > + depends on AGP || !AGPMy first thought was WTF? But then I realized that this totally makes sense. We should probably have the same for radeon as well. Apart from that the patch is Acked-by: Christian K?nig <christian.koenig at amd.com>> select IOMMU_API > select FW_LOADER > select DRM_KMS_HELPER > diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/pci/Kbuild b/drivers/gpu/drm/nouveau/nvkm/subdev/pci/Kbuild > index 174bdf995271..a400c680cf65 100644 > --- a/drivers/gpu/drm/nouveau/nvkm/subdev/pci/Kbuild > +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/pci/Kbuild > @@ -1,5 +1,5 @@ > # SPDX-License-Identifier: MIT > -nvkm-y += nvkm/subdev/pci/agp.o > +nvkm-$(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 <core/option.h> > > 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