On Wed, Feb 9, 2022 at 8:44 AM Varad Gautam <varad.gautam@xxxxxxxx> wrote:
>
> Processing CPUID #VC for AMD SEV-ES requires copying xcr0 into GHCB.
> Move the xsave read/write helpers used by xsave testcase to lib/x86
> to share as common code.
>
> Signed-off-by: Varad Gautam <varad.gautam@xxxxxxxx>
> ---
> lib/x86/xsave.c | 37 +++++++++++++++++++++++++++++++++++++
> lib/x86/xsave.h | 16 ++++++++++++++++
> x86/Makefile.common | 1 +
> x86/xsave.c | 43 +------------------------------------------
> 4 files changed, 55 insertions(+), 42 deletions(-)
> create mode 100644 lib/x86/xsave.c
> create mode 100644 lib/x86/xsave.h
>
> diff --git a/lib/x86/xsave.c b/lib/x86/xsave.c
> new file mode 100644
> index 0000000..1c0f16e
> --- /dev/null
> +++ b/lib/x86/xsave.c
> @@ -0,0 +1,37 @@
> +#include "libcflat.h"
> +#include "xsave.h"
> +#include "processor.h"
> +
> +int xgetbv_checking(u32 index, u64 *result)
> +{
> + u32 eax, edx;
> +
> + asm volatile(ASM_TRY("1f")
> + ".byte 0x0f,0x01,0xd0\n\t" /* xgetbv */
> + "1:"
> + : "=a" (eax), "=d" (edx)
> + : "c" (index));
> + *result = eax + ((u64)edx << 32);
> + return exception_vector();
> +}
> +
> +int xsetbv_checking(u32 index, u64 value)
> +{
> + u32 eax = value;
> + u32 edx = value >> 32;
> +
> + asm volatile(ASM_TRY("1f")
> + ".byte 0x0f,0x01,0xd1\n\t" /* xsetbv */
> + "1:"
> + : : "a" (eax), "d" (edx), "c" (index));
> + return exception_vector();
> +}
> +
> +uint64_t get_supported_xcr0(void)
> +{
> + struct cpuid r;
> + r = cpuid_indexed(0xd, 0);
> + printf("eax %x, ebx %x, ecx %x, edx %x\n",
> + r.a, r.b, r.c, r.d);
> + return r.a + ((u64)r.d << 32);
> +}
> diff --git a/lib/x86/xsave.h b/lib/x86/xsave.h
> new file mode 100644
> index 0000000..f1851a3
> --- /dev/null
> +++ b/lib/x86/xsave.h
> @@ -0,0 +1,16 @@
> +#ifndef _X86_XSAVE_H_
> +#define _X86_XSAVE_H_
> +
> +#define X86_CR4_OSXSAVE 0x00040000
> +#define XCR_XFEATURE_ENABLED_MASK 0x00000000
> +#define XCR_XFEATURE_ILLEGAL_MASK 0x00000010
> +
> +#define XSTATE_FP 0x1
> +#define XSTATE_SSE 0x2
> +#define XSTATE_YMM 0x4
> +
> +int xgetbv_checking(u32 index, u64 *result);
> +int xsetbv_checking(u32 index, u64 value);
> +uint64_t get_supported_xcr0(void);
> +
> +#endif
> diff --git a/x86/Makefile.common b/x86/Makefile.common
> index 2496d81..aa30948 100644
> --- a/x86/Makefile.common
> +++ b/x86/Makefile.common
> @@ -22,6 +22,7 @@ cflatobjs += lib/x86/acpi.o
> cflatobjs += lib/x86/stack.o
> cflatobjs += lib/x86/fault_test.o
> cflatobjs += lib/x86/delay.o
> +cflatobjs += lib/x86/xsave.o
> ifeq ($(TARGET_EFI),y)
> cflatobjs += lib/x86/amd_sev.o
> cflatobjs += lib/x86/amd_sev_vc.o
> diff --git a/x86/xsave.c b/x86/xsave.c
> index 892bf56..bd8fe11 100644
> --- a/x86/xsave.c
> +++ b/x86/xsave.c
> @@ -1,6 +1,7 @@
> #include "libcflat.h"
> #include "desc.h"
> #include "processor.h"
> +#include "xsave.h"
>
> #ifdef __x86_64__
> #define uint64_t unsigned long
> @@ -8,48 +9,6 @@
> #define uint64_t unsigned long long
> #endif
>
> -static int xgetbv_checking(u32 index, u64 *result)
> -{
> - u32 eax, edx;
> -
> - asm volatile(ASM_TRY("1f")
> - ".byte 0x0f,0x01,0xd0\n\t" /* xgetbv */
> - "1:"
> - : "=a" (eax), "=d" (edx)
> - : "c" (index));
> - *result = eax + ((u64)edx << 32);
> - return exception_vector();
> -}
> -
> -static int xsetbv_checking(u32 index, u64 value)
> -{
> - u32 eax = value;
> - u32 edx = value >> 32;
> -
> - asm volatile(ASM_TRY("1f")
> - ".byte 0x0f,0x01,0xd1\n\t" /* xsetbv */
> - "1:"
> - : : "a" (eax), "d" (edx), "c" (index));
> - return exception_vector();
> -}
> -
> -static uint64_t get_supported_xcr0(void)
> -{
> - struct cpuid r;
> - r = cpuid_indexed(0xd, 0);
> - printf("eax %x, ebx %x, ecx %x, edx %x\n",
> - r.a, r.b, r.c, r.d);
> - return r.a + ((u64)r.d << 32);
> -}
> -
> -#define X86_CR4_OSXSAVE 0x00040000
> -#define XCR_XFEATURE_ENABLED_MASK 0x00000000
> -#define XCR_XFEATURE_ILLEGAL_MASK 0x00000010
> -
> -#define XSTATE_FP 0x1
> -#define XSTATE_SSE 0x2
> -#define XSTATE_YMM 0x4
> -
> static void test_xsave(void)
> {
> unsigned long cr4;
> --
> 2.32.0
>
Reviewed-by: Marc Orr <marcorr@xxxxxxxxxx>
