From e15dd4949a937d8e8482f37f8fe493357417f203 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Fri, 4 Jul 2014 19:41:53 +0200 Subject: [PATCH] efi/arm64: Preserve FP/SIMD registers on UEFI runtime services calls According to the UEFI spec section 2.3.6.4, the use of FP/SIMD instructions is allowed, and should adhere to the AAPCS64 calling convention, which states that 'only the bottom 64 bits of each value stored in registers v8-v15 need to be preserved' (section 5.1.2). This applies equally to UEFI Runtime Services called by the kernel, so make sure the FP/SIMD register file is preserved in this case. We do this by enabling the wrappers for UEFI Runtime Services (CONFIG_EFI_RUNTIME_WRAPPERS) and inserting calls to kernel_neon_begin()and kernel_neon_end() into these wrappers. Signed-off-by: Ard Biesheuvel Acked-by: Catalin Marinas Signed-off-by: Matt Fleming --- arch/arm64/Kconfig | 1 + arch/arm64/include/asm/efi.h | 21 +++++++++++++++++++++ arch/arm64/kernel/efi.c | 14 +------------- 3 files changed, 23 insertions(+), 13 deletions(-) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 7295419165e1..2cc14cef01bd 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -298,6 +298,7 @@ config EFI select LIBFDT select UCS2_STRING select EFI_PARAMS_FROM_FDT + select EFI_RUNTIME_WRAPPERS default y help This option provides support for runtime services provided diff --git a/arch/arm64/include/asm/efi.h b/arch/arm64/include/asm/efi.h index 5a46c4e7f539..375ba342dca6 100644 --- a/arch/arm64/include/asm/efi.h +++ b/arch/arm64/include/asm/efi.h @@ -2,6 +2,7 @@ #define _ASM_EFI_H #include +#include #ifdef CONFIG_EFI extern void efi_init(void); @@ -11,4 +12,24 @@ extern void efi_idmap_init(void); #define efi_idmap_init() #endif +#define efi_call_virt(f, ...) \ +({ \ + efi_##f##_t *__f = efi.systab->runtime->f; \ + efi_status_t __s; \ + \ + kernel_neon_begin(); \ + __s = __f(__VA_ARGS__); \ + kernel_neon_end(); \ + __s; \ +}) + +#define __efi_call_virt(f, ...) \ +({ \ + efi_##f##_t *__f = efi.systab->runtime->f; \ + \ + kernel_neon_begin(); \ + __f(__VA_ARGS__); \ + kernel_neon_end(); \ +}) + #endif /* _ASM_EFI_H */ diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c index 14db1f6e8d7f..56c3327bbf79 100644 --- a/arch/arm64/kernel/efi.c +++ b/arch/arm64/kernel/efi.c @@ -449,19 +449,7 @@ static int __init arm64_enter_virtual_mode(void) /* Set up runtime services function pointers */ runtime = efi.systab->runtime; - efi.get_time = runtime->get_time; - efi.set_time = runtime->set_time; - efi.get_wakeup_time = runtime->get_wakeup_time; - efi.set_wakeup_time = runtime->set_wakeup_time; - efi.get_variable = runtime->get_variable; - efi.get_next_variable = runtime->get_next_variable; - efi.set_variable = runtime->set_variable; - efi.query_variable_info = runtime->query_variable_info; - efi.update_capsule = runtime->update_capsule; - efi.query_capsule_caps = runtime->query_capsule_caps; - efi.get_next_high_mono_count = runtime->get_next_high_mono_count; - efi.reset_system = runtime->reset_system; - + efi_native_runtime_setup(); set_bit(EFI_RUNTIME_SERVICES, &efi.flags); return 0; -- 2.20.1