In an S3 resume path, U-Boot does everything like a cold boot except in the last_stage_init() it jumps to the OS resume vector.
Signed-off-by: Bin Meng <bmeng...@gmail.com> --- arch/x86/cpu/cpu.c | 8 ++++++++ arch/x86/include/asm/acpi_s3.h | 10 ++++++++++ arch/x86/lib/Makefile | 1 + arch/x86/lib/acpi_s3.c | 26 ++++++++++++++++++++++++++ 4 files changed, 45 insertions(+) create mode 100644 arch/x86/lib/acpi_s3.c diff --git a/arch/x86/cpu/cpu.c b/arch/x86/cpu/cpu.c index 9dde54c..afc8645 100644 --- a/arch/x86/cpu/cpu.c +++ b/arch/x86/cpu/cpu.c @@ -26,6 +26,7 @@ #include <malloc.h> #include <syscon.h> #include <asm/acpi_s3.h> +#include <asm/acpi_table.h> #include <asm/control_regs.h> #include <asm/coreboot_tables.h> #include <asm/cpu.h> @@ -204,6 +205,13 @@ __weak void board_final_cleanup(void) int last_stage_init(void) { +#if CONFIG_HAVE_ACPI_RESUME + void *wake_vector = acpi_find_wakeup_vector(); + + if (wake_vector != NULL && gd->arch.prev_sleep_state == ACPI_S3) + acpi_resume(wake_vector); +#endif + write_tables(); board_final_cleanup(); diff --git a/arch/x86/include/asm/acpi_s3.h b/arch/x86/include/asm/acpi_s3.h index f9d4739..5892a8b 100644 --- a/arch/x86/include/asm/acpi_s3.h +++ b/arch/x86/include/asm/acpi_s3.h @@ -100,6 +100,16 @@ enum acpi_sleep_state chipset_prev_sleep_state(void); */ void chipset_clear_sleep_state(void); +/** + * acpi_resume() - Do ACPI S3 resume + * + * This calls U-Boot wake up assembly stub and jumps to OS's wake up vector. + * + * @wake_vec: OS wake up vector + * @return: Never returns + */ +void acpi_resume(void *wake_vec); + #endif /* __ASSEMBLY__ */ #endif /* __ASM_ACPI_S3_H__ */ diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile index 1c2c085..c61f931 100644 --- a/arch/x86/lib/Makefile +++ b/arch/x86/lib/Makefile @@ -35,6 +35,7 @@ obj-$(CONFIG_X86_RAMTEST) += ramtest.o obj-y += sections.o obj-y += sfi.o obj-y += string.o +obj-$(CONFIG_HAVE_ACPI_RESUME) += acpi_s3.o ifndef CONFIG_QEMU obj-$(CONFIG_GENERATE_ACPI_TABLE) += acpi_table.o endif diff --git a/arch/x86/lib/acpi_s3.c b/arch/x86/lib/acpi_s3.c new file mode 100644 index 0000000..f679c06 --- /dev/null +++ b/arch/x86/lib/acpi_s3.c @@ -0,0 +1,26 @@ +/* + * Copyright (C) 2017, Bin Meng <bmeng...@gmail.com> + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <asm/acpi_s3.h> +#include <asm/post.h> + +static void asmlinkage (*acpi_do_wakeup)(void *vector) = (void *)WAKEUP_BASE; + +static void acpi_jump_to_wakeup(void *vector) +{ + /* Copy wakeup trampoline in place */ + memcpy((void *)WAKEUP_BASE, __wakeup, __wakeup_size); + + printf("Jumping to OS waking vector %p\n", vector); + acpi_do_wakeup(vector); +} + +void acpi_resume(void *wake_vec) +{ + post_code(POST_OS_RESUME); + acpi_jump_to_wakeup(wake_vec); +} -- 2.9.2 _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot