x86: acpi: Refactor acpi_resume()

To do something more in acpi_resume() like turning on ACPI mode,
we need locate ACPI FADT table pointer first. But currently this
is done in acpi_find_wakeup_vector().

This changes acpi_resume() signature to accept ACPI FADT pointer
as the parameter. A new API acpi_find_fadt() is introduced, and
acpi_find_wakeup_vector() is updated to use FADT pointer as the
parameter as well.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Stefan Roese <sr@denx.de>

arch/x86/cpu/cpu.c

@@ -208,10 +208,10 @@ int last_stage_init(void)
 	board_final_cleanup();
 
 #if CONFIG_HAVE_ACPI_RESUME
-	void *wake_vector = acpi_find_wakeup_vector();
+	struct acpi_fadt *fadt = acpi_find_fadt();
 
-	if (wake_vector != NULL && gd->arch.prev_sleep_state == ACPI_S3)
+	if (fadt != NULL && gd->arch.prev_sleep_state == ACPI_S3)
-		acpi_resume(wake_vector);
+		acpi_resume(fadt);
 #endif
 
 	write_tables();

arch/x86/include/asm/acpi_s3.h

@@ -99,15 +99,16 @@ enum acpi_sleep_state chipset_prev_sleep_state(void);
  */
 void chipset_clear_sleep_state(void);
 
+struct acpi_fadt;
 /**
  * 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
+ * @fadt:	FADT table pointer in the ACPI table
  * @return:	Never returns
  */
-void acpi_resume(void *wake_vec);
+void acpi_resume(struct acpi_fadt *fadt);
 
 #endif /* __ASSEMBLY__ */
 

arch/x86/include/asm/acpi_table.h

@@ -327,6 +327,15 @@ void acpi_create_gnvs(struct acpi_global_nvs *gnvs);
 void enter_acpi_mode(int pm1_cnt);
 ulong write_acpi_tables(ulong start);
 
+/**
+ * acpi_find_fadt() - find ACPI FADT table in the sytem memory
+ *
+ * This routine parses the ACPI table to locate the ACPI FADT table.
+ *
+ * @return:	a pointer to the ACPI FADT table in the system memory
+ */
+struct acpi_fadt *acpi_find_fadt(void);
+
 /**
  * acpi_find_wakeup_vector() - find OS installed wake up vector address
  *
@@ -335,4 +344,4 @@ ulong write_acpi_tables(ulong start);
  *
  * @return:	wake up vector address installed by the OS
  */
-void *acpi_find_wakeup_vector(void);
+void *acpi_find_wakeup_vector(struct acpi_fadt *);

arch/x86/lib/acpi_s3.c

@@ -6,6 +6,7 @@
 
 #include <common.h>
 #include <asm/acpi_s3.h>
+#include <asm/acpi_table.h>
 #include <asm/post.h>
 
 static void asmlinkage (*acpi_do_wakeup)(void *vector) = (void *)WAKEUP_BASE;
@@ -19,8 +20,12 @@ static void acpi_jump_to_wakeup(void *vector)
 	acpi_do_wakeup(vector);
 }
 
-void acpi_resume(void *wake_vec)
+void acpi_resume(struct acpi_fadt *fadt)
 {
+	void *wake_vec;
+
+	wake_vec = acpi_find_wakeup_vector(fadt);
+
 	post_code(POST_OS_RESUME);
 	acpi_jump_to_wakeup(wake_vec);
 }

arch/x86/lib/acpi_table.c

@@ -460,18 +460,14 @@ static struct acpi_rsdp *acpi_valid_rsdp(struct acpi_rsdp *rsdp)
 	return rsdp;
 }
 
-void *acpi_find_wakeup_vector(void)
+struct acpi_fadt *acpi_find_fadt(void)
 {
 	char *p, *end;
 	struct acpi_rsdp *rsdp = NULL;
 	struct acpi_rsdt *rsdt;
 	struct acpi_fadt *fadt = NULL;
-	struct acpi_facs *facs;
-	void *wake_vec;
 	int i;
 
-	debug("Trying to find the wakeup vector...\n");
-
 	/* Find RSDP */
 	for (p = (char *)ROM_TABLE_ADDR; p < (char *)ROM_TABLE_END; p += 16) {
 		rsdp = acpi_valid_rsdp((struct acpi_rsdp *)p);
@@ -499,6 +495,16 @@ void *acpi_find_wakeup_vector(void)
 		return NULL;
 
 	debug("FADT found at %p\n", fadt);
+	return fadt;
+}
+
+void *acpi_find_wakeup_vector(struct acpi_fadt *fadt)
+{
+	struct acpi_facs *facs;
+	void *wake_vec;
+
+	debug("Trying to find the wakeup vector...\n");
+
 	facs = (struct acpi_facs *)fadt->firmware_ctrl;
 
 	if (facs == NULL) {