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>
Reviewed-by: Simon Glass <s...@chromium.org>
---
Changes in v2: None
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 7222ec8..f686ad4 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 a06466c..b8d14f4 100644
--- a/arch/x86/include/asm/acpi_s3.h
+++ b/arch/x86/include/asm/acpi_s3.h
@@ -99,6 +99,16 @@ 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 d1ad37a..21f59a0 100644
--- a/arch/x86/lib/Makefile
+++ b/arch/x86/lib/Makefile
@@ -37,6 +37,7 @@ obj-$(CONFIG_INTEL_MID) += scu.o
obj-y += sections.o
obj-y += sfi.o
obj-y += string.o
+obj-$(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
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