x86: Store and display previous sleep state

Add one member in the global data to store previous sleep state,
and display the state during boot in print_cpuinfo().

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

@@ -25,6 +25,7 @@
 #include <errno.h>
 #include <malloc.h>
 #include <syscon.h>
+#include <asm/acpi_s3.h>
 #include <asm/control_regs.h>
 #include <asm/coreboot_tables.h>
 #include <asm/cpu.h>
@@ -179,6 +180,11 @@ int default_print_cpuinfo(void)
 	       cpu_has_64bit() ? "x86_64" : "x86",
 	       cpu_vendor_name(gd->arch.x86_vendor), gd->arch.x86_device);
 
+#ifdef CONFIG_HAVE_ACPI_RESUME
+	debug("ACPI previous sleep state: %s\n",
+	      acpi_ss_string(gd->arch.prev_sleep_state));
+#endif
+
 	return 0;
 }
 

arch/x86/include/asm/acpi_s3.h

@@ -37,6 +37,19 @@ enum acpi_sleep_state {
 };
 
 /**
+ * acpi_ss_string() - get ACPI-defined sleep state string
+ *
+ * @pm1_cnt:	ACPI-defined sleep state
+ * @return:	a pointer to the sleep state string.
+ */
+static inline char *acpi_ss_string(enum acpi_sleep_state state)
+{
+	char *ss_string[] = { "S0", "S1", "S2", "S3", "S4", "S5"};
+
+	return ss_string[state];
+}
+
+/**
  * acpi_sleep_from_pm1() - get ACPI-defined sleep state from PM1_CNT register
  *
  * @pm1_cnt:	PM1_CNT register value

arch/x86/include/asm/global_data.h

@@ -99,6 +99,9 @@ struct arch_global_data {
 	u32 high_table_ptr;
 	u32 high_table_limit;
 #endif
+#ifdef CONFIG_HAVE_ACPI_RESUME
+	int prev_sleep_state;		/* Previous sleep state */
+#endif
 };
 
 #endif

arch/x86/lib/fsp/fsp_common.c

@@ -82,6 +82,7 @@ int arch_fsp_init(void)
 	int boot_mode = BOOT_FULL_CONFIG;
 #ifdef CONFIG_HAVE_ACPI_RESUME
 	int prev_sleep_state = chipset_prev_sleep_state();
+	gd->arch.prev_sleep_state = prev_sleep_state;
 #endif
 
 	if (!gd->arch.hob_list) {