x86: Enable SSE in 64-bit mode

This is needed to support Truetype fonts. In any case, the compiler
expects SSE to be available in 64-bit mode. Provide an option to enable
SSE so that hardware floating-point arithmetic works.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
Suggested-by: Bin Meng <bmeng.cn@gmail.com>

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 99e59d94c6069bf97a682fcf4089ecf1a9e83bc3..6b532d712ee8e05b73cb137e9eda2d14f45d132c 100644 (file)
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -723,6 +723,14 @@ config ROM_TABLE_SIZE
        hex
        default 0x10000
 
+config X86_HARDFP
+       bool "Support hardware floating point"
+       help
+         U-Boot generally does not make use of floating point. Where this is
+         needed, it can be enabled using this option. This adjusts the
+         start-up code for 64-bit mode and changes the compiler options for
+         64-bit to enable SSE.
+
 config HAVE_ITSS
        bool "Enable ITSS"
        help

diff --git a/arch/x86/config.mk b/arch/x86/config.mk
index 26ec1af2f0b09e008c0a0ce5e916f5170dd8e6fe..2e3a7119e798b2068d7df74711cb3eca3991eefd 100644 (file)
--- a/arch/x86/config.mk
+++ b/arch/x86/config.mk
@@ -27,9 +27,13 @@ ifeq ($(IS_32BIT),y)
 PLATFORM_CPPFLAGS += -march=i386 -m32
 else
 PLATFORM_CPPFLAGS += $(if $(CONFIG_SPL_BUILD),,-fpic) -fno-common -march=core2 -m64
+
+ifndef CONFIG_X86_HARDFP
 PLATFORM_CPPFLAGS += -mno-mmx -mno-sse
 endif
 
+endif # IS_32BIT
+
 PLATFORM_RELFLAGS += -fdata-sections -ffunction-sections -fvisibility=hidden
 
 KBUILD_LDFLAGS += -Bsymbolic -Bsymbolic-functions

diff --git a/arch/x86/cpu/x86_64/cpu.c b/arch/x86/cpu/x86_64/cpu.c
index 2647bff891f86046a8388961af649c9165af8c9d..5ea746ecce4ddb15b9fc643ba2327ca2a1c8f5a5 100644 (file)
--- a/arch/x86/cpu/x86_64/cpu.c
+++ b/arch/x86/cpu/x86_64/cpu.c
@@ -10,6 +10,7 @@
 #include <init.h>
 #include <asm/cpu.h>
 #include <asm/global_data.h>
+#include <asm/processor-flags.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
@@ -39,11 +40,22 @@ int x86_mp_init(void)
        return 0;
 }
 
+/* enable SSE features for hardware floating point */
+static void setup_sse_features(void)
+{
+       asm ("mov %%cr4, %%rax\n" \
+       "or  %0, %%rax\n" \
+       "mov %%rax, %%cr4\n" \
+       : : "i" (X86_CR4_OSFXSR | X86_CR4_OSXMMEXCPT) : "eax");
+}
+
 int x86_cpu_reinit_f(void)
 {
        /* set the vendor to Intel so that native_calibrate_tsc() works */
        gd->arch.x86_vendor = X86_VENDOR_INTEL;
        gd->arch.has_mtrr = true;
+       if (IS_ENABLED(CONFIG_X86_HARDFP))
+               setup_sse_features();
 
        return 0;
 }

diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index 6f319ba0d544efa45b18e5871e4a1ddd08b448ff..39c82521be1613813e47579c43c9c98625c7011b 100644 (file)
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -180,6 +180,7 @@ config CONSOLE_ROTATION
 
 config CONSOLE_TRUETYPE
        bool "Support a console that uses TrueType fonts"
+       select X86_HARDFP if X86
        help
          TrueTrype fonts can provide outline-drawing capability rather than
          needing to provide a bitmap for each font and size that is needed.