On 2021-01-21 4:20 a.m., Ard Biesheuvel wrote:
From: Alex Deucher alexander.deucher@amd.com
commit c241ed2f0ea549c18cff62a3708b43846b84dae3 upstream.
From Ard:
"Simply disabling -mgeneral-regs-only left and right is risky, given that the standard AArch64 ABI permits the use of FP/SIMD registers anywhere, and GCC is known to use SIMD registers for spilling, and may invent other uses of the FP/SIMD register file that have nothing to do with the floating point code in question. Note that putting kernel_neon_begin() and kernel_neon_end() around the code that does use FP is not sufficient here, the problem is in all the other code that may be emitted with references to SIMD registers in it.
So the only way to do this properly is to put all floating point code in a separate compilation unit, and only compile that unit with -mgeneral-regs-only."
Disable support until the code can be properly refactored to support this properly on aarch64.
Acked-by: Will Deacon will@kernel.org Reported-by: Ard Biesheuvel ardb@kernel.org Signed-off-by: Alex Deucher alexander.deucher@amd.com [ardb: backport to v5.10 by reverting c38d444e44badc55 instead] Acked-by: Alex Deucher alexander.deucher@amd.com # v5.10 backport
Acked-by: Harry Wentland harry.wentland@amd.com
Harry
Signed-off-by: Ard Biesheuvel ardb@kernel.org
The original commit does not apply cleanly to v5.10, as it reverts a combination of patches, some of which are not present in v5.10.
This patch is a straight revert of c38d444e44badc55, which is the only change that needs to be backed out from v5.10, and amounts to the same thing as the original mainline commit.
drivers/gpu/drm/amd/display/Kconfig | 2 +- drivers/gpu/drm/amd/display/dc/calcs/Makefile | 7 -- drivers/gpu/drm/amd/display/dc/clk_mgr/Makefile | 7 -- drivers/gpu/drm/amd/display/dc/dcn10/Makefile | 7 -- drivers/gpu/drm/amd/display/dc/dcn10/dcn10_resource.c | 81 ++++++++------------ drivers/gpu/drm/amd/display/dc/dcn20/Makefile | 4 - drivers/gpu/drm/amd/display/dc/dcn21/Makefile | 4 - drivers/gpu/drm/amd/display/dc/dml/Makefile | 13 ---- drivers/gpu/drm/amd/display/dc/dsc/Makefile | 5 -- drivers/gpu/drm/amd/display/dc/os_types.h | 4 - 10 files changed, 32 insertions(+), 102 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/Kconfig b/drivers/gpu/drm/amd/display/Kconfig index 60dfdd432aba..3c410d236c49 100644 --- a/drivers/gpu/drm/amd/display/Kconfig +++ b/drivers/gpu/drm/amd/display/Kconfig @@ -6,7 +6,7 @@ config DRM_AMD_DC bool "AMD DC - Enable new display engine" default y select SND_HDA_COMPONENT if SND_HDA_CORE
- select DRM_AMD_DC_DCN if (X86 || PPC64 || (ARM64 && KERNEL_MODE_NEON)) && !(KCOV_INSTRUMENT_ALL && KCOV_ENABLE_COMPARISONS)
- select DRM_AMD_DC_DCN if (X86 || PPC64) && !(KCOV_INSTRUMENT_ALL && KCOV_ENABLE_COMPARISONS) help Choose this option if you want to use the new display engine support for AMDGPU. This adds required support for Vega and
diff --git a/drivers/gpu/drm/amd/display/dc/calcs/Makefile b/drivers/gpu/drm/amd/display/dc/calcs/Makefile index 64f515d74410..4674aca8f206 100644 --- a/drivers/gpu/drm/amd/display/dc/calcs/Makefile +++ b/drivers/gpu/drm/amd/display/dc/calcs/Makefile @@ -33,10 +33,6 @@ ifdef CONFIG_PPC64 calcs_ccflags := -mhard-float -maltivec endif -ifdef CONFIG_ARM64 -calcs_rcflags := -mgeneral-regs-only -endif
- ifdef CONFIG_CC_IS_GCC ifeq ($(call cc-ifversion, -lt, 0701, y), y) IS_OLD_GCC = 1
@@ -57,9 +53,6 @@ endif CFLAGS_$(AMDDALPATH)/dc/calcs/dcn_calcs.o := $(calcs_ccflags) CFLAGS_$(AMDDALPATH)/dc/calcs/dcn_calc_auto.o := $(calcs_ccflags) CFLAGS_$(AMDDALPATH)/dc/calcs/dcn_calc_math.o := $(calcs_ccflags) -Wno-tautological-compare -CFLAGS_REMOVE_$(AMDDALPATH)/dc/calcs/dcn_calcs.o := $(calcs_rcflags) -CFLAGS_REMOVE_$(AMDDALPATH)/dc/calcs/dcn_calc_auto.o := $(calcs_rcflags) -CFLAGS_REMOVE_$(AMDDALPATH)/dc/calcs/dcn_calc_math.o := $(calcs_rcflags) BW_CALCS = dce_calcs.o bw_fixed.o custom_float.o diff --git a/drivers/gpu/drm/amd/display/dc/clk_mgr/Makefile b/drivers/gpu/drm/amd/display/dc/clk_mgr/Makefile index 1a495759a034..52b1ce775a1e 100644 --- a/drivers/gpu/drm/amd/display/dc/clk_mgr/Makefile +++ b/drivers/gpu/drm/amd/display/dc/clk_mgr/Makefile @@ -104,13 +104,6 @@ ifdef CONFIG_PPC64 CFLAGS_$(AMDDALPATH)/dc/clk_mgr/dcn21/rn_clk_mgr.o := $(call cc-option,-mno-gnu-attribute) endif -# prevent build errors: -# ...: '-mgeneral-regs-only' is incompatible with the use of floating-point types -# this file is unused on arm64, just like on ppc64 -ifdef CONFIG_ARM64 -CFLAGS_REMOVE_$(AMDDALPATH)/dc/clk_mgr/dcn21/rn_clk_mgr.o := -mgeneral-regs-only -endif
- AMD_DAL_CLK_MGR_DCN21 = $(addprefix $(AMDDALPATH)/dc/clk_mgr/dcn21/,$(CLK_MGR_DCN21))
AMD_DISPLAY_FILES += $(AMD_DAL_CLK_MGR_DCN21) diff --git a/drivers/gpu/drm/amd/display/dc/dcn10/Makefile b/drivers/gpu/drm/amd/display/dc/dcn10/Makefile index 733e6e6e43bd..62ad1a11bff9 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn10/Makefile +++ b/drivers/gpu/drm/amd/display/dc/dcn10/Makefile @@ -31,11 +31,4 @@ DCN10 = dcn10_init.o dcn10_resource.o dcn10_ipp.o dcn10_hw_sequencer.o \ AMD_DAL_DCN10 = $(addprefix $(AMDDALPATH)/dc/dcn10/,$(DCN10)) -# fix: -# ...: '-mgeneral-regs-only' is incompatible with the use of floating-point types -# aarch64 does not support soft-float, so use hard-float and handle this in code -ifdef CONFIG_ARM64 -CFLAGS_REMOVE_$(AMDDALPATH)/dc/dcn10/dcn10_resource.o := -mgeneral-regs-only -endif
- AMD_DISPLAY_FILES += $(AMD_DAL_DCN10)
diff --git a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_resource.c b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_resource.c index a78712caf124..462d3d981ea5 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_resource.c +++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_resource.c @@ -1339,47 +1339,6 @@ static uint32_t read_pipe_fuses(struct dc_context *ctx) return value; } -/*
- Some architectures don't support soft-float (e.g. aarch64), on those
- this function has to be called with hardfloat enabled, make sure not
- to inline it so whatever fp stuff is done stays inside
- */
-static noinline void dcn10_resource_construct_fp(
- struct dc *dc)
-{
- if (dc->ctx->dce_version == DCN_VERSION_1_01) {
struct dcn_soc_bounding_box *dcn_soc = dc->dcn_soc;struct dcn_ip_params *dcn_ip = dc->dcn_ip;struct display_mode_lib *dml = &dc->dml;dml->ip.max_num_dpp = 3;/* TODO how to handle 23.84? */dcn_soc->dram_clock_change_latency = 23;dcn_ip->max_num_dpp = 3;- }
- if (ASICREV_IS_RV1_F0(dc->ctx->asic_id.hw_internal_rev)) {
dc->dcn_soc->urgent_latency = 3;dc->debug.disable_dmcu = true;dc->dcn_soc->fabric_and_dram_bandwidth_vmax0p9 = 41.60f;- }
- dc->dcn_soc->number_of_channels = dc->ctx->asic_id.vram_width / ddr4_dram_width;
- ASSERT(dc->dcn_soc->number_of_channels < 3);
- if (dc->dcn_soc->number_of_channels == 0)/*old sbios bug*/
dc->dcn_soc->number_of_channels = 2;- if (dc->dcn_soc->number_of_channels == 1) {
dc->dcn_soc->fabric_and_dram_bandwidth_vmax0p9 = 19.2f;dc->dcn_soc->fabric_and_dram_bandwidth_vnom0p8 = 17.066f;dc->dcn_soc->fabric_and_dram_bandwidth_vmid0p72 = 14.933f;dc->dcn_soc->fabric_and_dram_bandwidth_vmin0p65 = 12.8f;if (ASICREV_IS_RV1_F0(dc->ctx->asic_id.hw_internal_rev)) {dc->dcn_soc->fabric_and_dram_bandwidth_vmax0p9 = 20.80f;}- }
-}
- static bool dcn10_resource_construct( uint8_t num_virtual_links, struct dc *dc,
@@ -1531,15 +1490,37 @@ static bool dcn10_resource_construct( memcpy(dc->dcn_ip, &dcn10_ip_defaults, sizeof(dcn10_ip_defaults)); memcpy(dc->dcn_soc, &dcn10_soc_defaults, sizeof(dcn10_soc_defaults)); -#if defined(CONFIG_ARM64)
- /* Aarch64 does not support -msoft-float/-mfloat-abi=soft */
- DC_FP_START();
- dcn10_resource_construct_fp(dc);
- DC_FP_END();
-#else
- /* Other architectures we build for build this with soft-float */
- dcn10_resource_construct_fp(dc);
-#endif
- if (dc->ctx->dce_version == DCN_VERSION_1_01) {
struct dcn_soc_bounding_box *dcn_soc = dc->dcn_soc;struct dcn_ip_params *dcn_ip = dc->dcn_ip;struct display_mode_lib *dml = &dc->dml;dml->ip.max_num_dpp = 3;/* TODO how to handle 23.84? */dcn_soc->dram_clock_change_latency = 23;dcn_ip->max_num_dpp = 3;- }
- if (ASICREV_IS_RV1_F0(dc->ctx->asic_id.hw_internal_rev)) {
dc->dcn_soc->urgent_latency = 3;dc->debug.disable_dmcu = true;dc->dcn_soc->fabric_and_dram_bandwidth_vmax0p9 = 41.60f;- }
- dc->dcn_soc->number_of_channels = dc->ctx->asic_id.vram_width / ddr4_dram_width;
- ASSERT(dc->dcn_soc->number_of_channels < 3);
- if (dc->dcn_soc->number_of_channels == 0)/*old sbios bug*/
dc->dcn_soc->number_of_channels = 2;- if (dc->dcn_soc->number_of_channels == 1) {
dc->dcn_soc->fabric_and_dram_bandwidth_vmax0p9 = 19.2f;dc->dcn_soc->fabric_and_dram_bandwidth_vnom0p8 = 17.066f;dc->dcn_soc->fabric_and_dram_bandwidth_vmid0p72 = 14.933f;dc->dcn_soc->fabric_and_dram_bandwidth_vmin0p65 = 12.8f;if (ASICREV_IS_RV1_F0(dc->ctx->asic_id.hw_internal_rev)) {dc->dcn_soc->fabric_and_dram_bandwidth_vmax0p9 = 20.80f;}- }
pool->base.pp_smu = dcn10_pp_smu_create(ctx); diff --git a/drivers/gpu/drm/amd/display/dc/dcn20/Makefile b/drivers/gpu/drm/amd/display/dc/dcn20/Makefile index 624cb1341ef1..5fcaf78334ff 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn20/Makefile +++ b/drivers/gpu/drm/amd/display/dc/dcn20/Makefile @@ -17,10 +17,6 @@ ifdef CONFIG_PPC64 CFLAGS_$(AMDDALPATH)/dc/dcn20/dcn20_resource.o := -mhard-float -maltivec endif -ifdef CONFIG_ARM64 -CFLAGS_REMOVE_$(AMDDALPATH)/dc/dcn20/dcn20_resource.o := -mgeneral-regs-only -endif
- ifdef CONFIG_CC_IS_GCC ifeq ($(call cc-ifversion, -lt, 0701, y), y) IS_OLD_GCC = 1
diff --git a/drivers/gpu/drm/amd/display/dc/dcn21/Makefile b/drivers/gpu/drm/amd/display/dc/dcn21/Makefile index 51a2f3d4c194..07684d3e375a 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn21/Makefile +++ b/drivers/gpu/drm/amd/display/dc/dcn21/Makefile @@ -13,10 +13,6 @@ ifdef CONFIG_PPC64 CFLAGS_$(AMDDALPATH)/dc/dcn21/dcn21_resource.o := -mhard-float -maltivec endif -ifdef CONFIG_ARM64 -CFLAGS_REMOVE_$(AMDDALPATH)/dc/dcn21/dcn21_resource.o := -mgeneral-regs-only -endif
- ifdef CONFIG_CC_IS_GCC ifeq ($(call cc-ifversion, -lt, 0701, y), y) IS_OLD_GCC = 1
diff --git a/drivers/gpu/drm/amd/display/dc/dml/Makefile b/drivers/gpu/drm/amd/display/dc/dml/Makefile index dbc7e2abe379..417331438c30 100644 --- a/drivers/gpu/drm/amd/display/dc/dml/Makefile +++ b/drivers/gpu/drm/amd/display/dc/dml/Makefile @@ -33,10 +33,6 @@ ifdef CONFIG_PPC64 dml_ccflags := -mhard-float -maltivec endif -ifdef CONFIG_ARM64 -dml_rcflags := -mgeneral-regs-only -endif
- ifdef CONFIG_CC_IS_GCC ifeq ($(call cc-ifversion, -lt, 0701, y), y) IS_OLD_GCC = 1
@@ -64,13 +60,6 @@ CFLAGS_$(AMDDALPATH)/dc/dml/dcn20/display_mode_vba_20v2.o := $(dml_ccflags) CFLAGS_$(AMDDALPATH)/dc/dml/dcn20/display_rq_dlg_calc_20v2.o := $(dml_ccflags) CFLAGS_$(AMDDALPATH)/dc/dml/dcn21/display_mode_vba_21.o := $(dml_ccflags) CFLAGS_$(AMDDALPATH)/dc/dml/dcn21/display_rq_dlg_calc_21.o := $(dml_ccflags) -CFLAGS_REMOVE_$(AMDDALPATH)/dc/dml/display_mode_vba.o := $(dml_rcflags) -CFLAGS_REMOVE_$(AMDDALPATH)/dc/dml/dcn20/display_mode_vba_20.o := $(dml_rcflags) -CFLAGS_REMOVE_$(AMDDALPATH)/dc/dml/dcn20/display_rq_dlg_calc_20.o := $(dml_rcflags) -CFLAGS_REMOVE_$(AMDDALPATH)/dc/dml/dcn20/display_mode_vba_20v2.o := $(dml_rcflags) -CFLAGS_REMOVE_$(AMDDALPATH)/dc/dml/dcn20/display_rq_dlg_calc_20v2.o := $(dml_rcflags) -CFLAGS_REMOVE_$(AMDDALPATH)/dc/dml/dcn21/display_mode_vba_21.o := $(dml_rcflags) -CFLAGS_REMOVE_$(AMDDALPATH)/dc/dml/dcn21/display_rq_dlg_calc_21.o := $(dml_rcflags) endif ifdef CONFIG_DRM_AMD_DC_DCN3_0 CFLAGS_$(AMDDALPATH)/dc/dml/dcn30/display_mode_vba_30.o := $(dml_ccflags) -Wframe-larger-than=2048 @@ -78,8 +67,6 @@ CFLAGS_$(AMDDALPATH)/dc/dml/dcn30/display_rq_dlg_calc_30.o := $(dml_ccflags) endif CFLAGS_$(AMDDALPATH)/dc/dml/dml1_display_rq_dlg_calc.o := $(dml_ccflags) CFLAGS_$(AMDDALPATH)/dc/dml/display_rq_dlg_helpers.o := $(dml_ccflags) -CFLAGS_REMOVE_$(AMDDALPATH)/dc/dml/dml1_display_rq_dlg_calc.o := $(dml_rcflags) -CFLAGS_REMOVE_$(AMDDALPATH)/dc/dml/display_rq_dlg_helpers.o := $(dml_rcflags) DML = display_mode_lib.o display_rq_dlg_helpers.o dml1_display_rq_dlg_calc.o \ diff --git a/drivers/gpu/drm/amd/display/dc/dsc/Makefile b/drivers/gpu/drm/amd/display/dc/dsc/Makefile index f2624a1156e5..ea29cf95d470 100644 --- a/drivers/gpu/drm/amd/display/dc/dsc/Makefile +++ b/drivers/gpu/drm/amd/display/dc/dsc/Makefile @@ -10,10 +10,6 @@ ifdef CONFIG_PPC64 dsc_ccflags := -mhard-float -maltivec endif -ifdef CONFIG_ARM64 -dsc_rcflags := -mgeneral-regs-only -endif
- ifdef CONFIG_CC_IS_GCC ifeq ($(call cc-ifversion, -lt, 0701, y), y) IS_OLD_GCC = 1
@@ -32,7 +28,6 @@ endif endif CFLAGS_$(AMDDALPATH)/dc/dsc/rc_calc.o := $(dsc_ccflags) -CFLAGS_REMOVE_$(AMDDALPATH)/dc/dsc/rc_calc.o := $(dsc_rcflags) DSC = dc_dsc.o rc_calc.o rc_calc_dpi.o diff --git a/drivers/gpu/drm/amd/display/dc/os_types.h b/drivers/gpu/drm/amd/display/dc/os_types.h index 95cb56929e79..126c2f3a4dd3 100644 --- a/drivers/gpu/drm/amd/display/dc/os_types.h +++ b/drivers/gpu/drm/amd/display/dc/os_types.h @@ -55,10 +55,6 @@ #include <asm/fpu/api.h> #define DC_FP_START() kernel_fpu_begin() #define DC_FP_END() kernel_fpu_end() -#elif defined(CONFIG_ARM64) -#include <asm/neon.h> -#define DC_FP_START() kernel_neon_begin() -#define DC_FP_END() kernel_neon_end() #elif defined(CONFIG_PPC64) #include <asm/switch_to.h> #include <asm/cputable.h>