On Mon, Jun 20, 2022 at 05:51:04PM -0400, Alex Deucher wrote:

On Sat, Jun 18, 2022 at 7:27 PM Guenter Roeck linux@roeck-us.net wrote:

...

ppc:allmodconfig builds fail with the following error.

powerpc64-linux-ld: drivers/gpu/drm/amd/amdgpu/../display/dc/dml/display_mode_lib.o uses hard float, drivers/gpu/drm/amd/amdgpu/../display/dc/dcn31/dcn31_resource.o uses soft float powerpc64-linux-ld: failed to merge target specific data of file drivers/gpu/drm/amd/amdgpu/../display/dc/dcn31/dcn31_resource.o powerpc64-linux-ld: drivers/gpu/drm/amd/amdgpu/../display/dc/dml/display_mode_lib.o uses hard float, drivers/gpu/drm/amd/amdgpu/../display/dc/dcn315/dcn315_resource.o uses soft float powerpc64-linux-ld: failed to merge target specific data of file drivers/gpu/drm/amd/amdgpu/../display/dc/dcn315/dcn315_resource.o powerpc64-linux-ld: drivers/gpu/drm/amd/amdgpu/../display/dc/dml/display_mode_lib.o uses hard float, drivers/gpu/drm/amd/amdgpu/../display/dc/dcn316/dcn316_resource.o uses soft float powerpc64-linux-ld: failed to merge target specific data of file drivers/gpu/drm/amd/amdgpu/../display/dc/dcn316/dcn316_resource.o

The problem was introduced with commit 41b7a347bf14 ("powerpc: Book3S 64-bit outline-only KASAN support") which adds support for KASAN. This commit in turn enables DRM_AMD_DC_DCN because KCOV_INSTRUMENT_ALL and KCOV_ENABLE_COMPARISONS are no longer enabled. As result, new files are compiled which lack the selection of hard-float.

Fixes: 41b7a347bf14 ("powerpc: Book3S 64-bit outline-only KASAN support") Cc: Michael Ellerman mpe@ellerman.id.au Cc: Daniel Axtens dja@axtens.net Signed-off-by: Guenter Roeck linux@roeck-us.net

---

drivers/gpu/drm/amd/display/dc/dcn31/Makefile | 4 ++++ drivers/gpu/drm/amd/display/dc/dcn315/Makefile | 4 ++++ drivers/gpu/drm/amd/display/dc/dcn316/Makefile | 4 ++++ 3 files changed, 12 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/dc/dcn31/Makefile b/drivers/gpu/drm/amd/display/dc/dcn31/Makefile index ec041e3cda30..74be02114ae4 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn31/Makefile +++ b/drivers/gpu/drm/amd/display/dc/dcn31/Makefile @@ -15,6 +15,10 @@ DCN31 = dcn31_resource.o dcn31_hubbub.o dcn31_hwseq.o dcn31_init.o dcn31_hubp.o dcn31_apg.o dcn31_hpo_dp_stream_encoder.o dcn31_hpo_dp_link_encoder.o \ dcn31_afmt.o dcn31_vpg.o

+ifdef CONFIG_PPC64 +CFLAGS_$(AMDDALPATH)/dc/dcn31/dcn31_resource.o := -mhard-float -maltivec +endif

This stuff was all moved as part of the FP rework in: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... @Siqueira, Rodrigo , @Melissa Wen, @Dhillon, Jasdeep can you take a look to understand why this is necessary? If we add back the PPC flags, I think we need to add back the x86 ones as well.

For my part I have no idea. All I can see is that powerpc:allmodconfig builds fail with the above errors. I have not seen any build errors with other architectures.

Guenter

Alex

...

AMD_DAL_DCN31 = $(addprefix $(AMDDALPATH)/dc/dcn31/,$(DCN31))

AMD_DISPLAY_FILES += $(AMD_DAL_DCN31) diff --git a/drivers/gpu/drm/amd/display/dc/dcn315/Makefile b/drivers/gpu/drm/amd/display/dc/dcn315/Makefile index 59381d24800b..1395c1ced8c5 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn315/Makefile +++ b/drivers/gpu/drm/amd/display/dc/dcn315/Makefile @@ -25,6 +25,10 @@

DCN315 = dcn315_resource.o

+ifdef CONFIG_PPC64 +CFLAGS_$(AMDDALPATH)/dc/dcn315/dcn315_resource.o := -mhard-float -maltivec +endif

AMD_DAL_DCN315 = $(addprefix $(AMDDALPATH)/dc/dcn315/,$(DCN315))

AMD_DISPLAY_FILES += $(AMD_DAL_DCN315) diff --git a/drivers/gpu/drm/amd/display/dc/dcn316/Makefile b/drivers/gpu/drm/amd/display/dc/dcn316/Makefile index 819d44a9439b..c3d2dd78f1e2 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn316/Makefile +++ b/drivers/gpu/drm/amd/display/dc/dcn316/Makefile @@ -25,6 +25,10 @@

DCN316 = dcn316_resource.o

+ifdef CONFIG_PPC64 +CFLAGS_$(AMDDALPATH)/dc/dcn316/dcn316_resource.o := -mhard-float -maltivec +endif

AMD_DAL_DCN316 = $(addprefix $(AMDDALPATH)/dc/dcn316/,$(DCN316))

AMD_DISPLAY_FILES += $(AMD_DAL_DCN316)

2.35.1