Commit 8f83e6e6 authored Jan 24, 2019 by ndesaulniers@google.com Committed by Alistair Strachan May 20, 2019

BACKPORT: drm/amd/display: add -msse2 to prevent Clang from emitting libcalls...

BACKPORT: drm/amd/display: add -msse2 to prevent Clang from emitting libcalls to undefined SW FP routines

arch/x86/Makefile disables SSE and SSE2 for the whole kernel.  The
AMDGPU drivers modified in this patch re-enable SSE but not SSE2.  Turn
on SSE2 to support emitting double precision floating point instructions
rather than calls to non-existent (usually available from gcc_s or
compiler_rt) floating point helper routines.

Link: https://gcc.gnu.org/onlinedocs/gccint/Soft-float-library-routines.html
Link: https://github.com/ClangBuiltLinux/linux/issues/327


Cc: stable@vger.kernel.org # 4.19
Reported-by: S, Shirish <Shirish.S@amd.com>
Reported-by: Matthias Kaehlcke <mka@google.com>
Suggested-by: James Y Knight <jyknight@google.com>
Suggested-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Matthias Kaehlcke <mka@chromium.org>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Change-Id: I653676f209c85d1c27c91af1c9347ee59107b04f
(cherry picked from commit 10117450735c7a7c0858095fb46a860e7037cb9a)
[ added CONFIG_CC_IS_CLANG ]
Link: https://bugs.freedesktop.org/show_bug.cgi?id=109487


Signed-off-by: Sami Tolvanen <samitolvanen@google.com>

parent 3215ed43

drivers/gpu/drm/amd/display/dc/calcs/Makefile

+6 −0

Original line number	Diff line number	Diff line
		@@ -32,6 +32,12 @@ endif

		calcs_ccflags := -mhard-float -msse $(cc_stack_align)

		# Use -msse2 only with clang:
		# https://bugs.freedesktop.org/show_bug.cgi?id=109487
		ifdef CONFIG_CC_IS_CLANG
		calcs_cc_flags += -msse2
		endif

		CFLAGS_dcn_calcs.o := $(calcs_ccflags)
		CFLAGS_dcn_calc_auto.o := $(calcs_ccflags)
		CFLAGS_dcn_calc_math.o := $(calcs_ccflags) -Wno-tautological-compare

drivers/gpu/drm/amd/display/dc/dml/Makefile

+6 −0

Original line number	Diff line number	Diff line
		@@ -32,6 +32,12 @@ endif

		dml_ccflags := -mhard-float -msse $(cc_stack_align)

		# Use -msse2 only with clang:
		# https://bugs.freedesktop.org/show_bug.cgi?id=109487
		ifdef CONFIG_CC_IS_CLANG
		dml_ccflags += -msse2
		endif

		CFLAGS_display_mode_lib.o := $(dml_ccflags)
		CFLAGS_display_pipe_clocks.o := $(dml_ccflags)
		CFLAGS_dml1_display_rq_dlg_calc.o := $(dml_ccflags)