x86: acpi: Pack global NVS into ACPI table

Now that platform-specific ACPI global NVS is added, pack it into
ACPI table and get its address fixed up.
Signed-off-by: NBin Meng <bmeng.cn@gmail.com>
Reviewed-by: NGeorge McCollister <george.mccollister@gmail.com>
Tested-by: NGeorge McCollister <george.mccollister@gmail.com>
Reviewed-by: NSimon Glass <sjg@chromium.org>

arch/x86/include/asm/acpi_table.h

@@ -299,6 +299,9 @@ struct acpi_mcfg_mmconfig {
 /* PM1_CNT bit defines */
 #define PM1_CNT_SCI_EN		(1 << 0)
 
+/* ACPI global NVS structure */
+struct acpi_global_nvs;
+
 /* These can be used by the target port */
 
 void acpi_fill_header(struct acpi_table_header *header, char *signature);
@@ -312,4 +315,5 @@ int acpi_create_madt_irqoverride(struct acpi_madt_irqoverride *irqoverride,
 int acpi_create_madt_lapic_nmi(struct acpi_madt_lapic_nmi *lapic_nmi,
 			       u8 cpu, u16 flags, u8 lint);
 u32 acpi_fill_madt(u32 current);
+void acpi_create_gnvs(struct acpi_global_nvs *gnvs);
 u32 write_acpi_tables(u32 start);

arch/x86/include/asm/arch-baytrail/acpi/platform.asl

@@ -22,6 +22,9 @@ Method(_WAK, 1)
 	Return (Package() {0, 0})
 }
 
+/* ACPI global NVS */
+#include "global_nvs.asl"
+
 /* TODO: add CPU ASL support */
 
 Scope (\_SB)

arch/x86/include/asm/arch-quark/acpi/platform.asl

@@ -22,6 +22,9 @@ Method(_WAK, 1)
 	Return (Package() {0, 0})
 }
 
+/* ACPI global NVS */
+#include "global_nvs.asl"
+
 /* TODO: add CPU ASL support */
 
 Scope (\_SB)

arch/x86/lib/acpi_table.c

@@ -11,10 +11,12 @@
 #include <cpu.h>
 #include <dm.h>
 #include <dm/uclass-internal.h>
+#include <asm/acpi/global_nvs.h>
 #include <asm/acpi_table.h>
 #include <asm/io.h>
 #include <asm/lapic.h>
 #include <asm/tables.h>
+#include <asm/arch/global_nvs.h>
 
 /*
  * IASL compiles the dsdt entries and writes the hex values
@@ -336,6 +338,7 @@ u32 write_acpi_tables(u32 start)
 	struct acpi_fadt *fadt;
 	struct acpi_mcfg *mcfg;
 	struct acpi_madt *madt;
+	int i;
 
 	current = start;
 
@@ -383,6 +386,25 @@ u32 write_acpi_tables(u32 start)
 	current += dsdt->length - sizeof(struct acpi_table_header);
 	current = ALIGN(current, 16);
 
+	/* Pack GNVS into the ACPI table area */
+	for (i = 0; i < dsdt->length; i++) {
+		u32 *gnvs = (u32 *)((u32)dsdt + i);
+		if (*gnvs == ACPI_GNVS_ADDR) {
+			debug("Fix up global NVS in DSDT to 0x%08x\n", current);
+			*gnvs = current;
+			break;
+		}
+	}
+
+	/* Update DSDT checksum since we patched the GNVS address */
+	dsdt->checksum = 0;
+	dsdt->checksum = table_compute_checksum((void *)dsdt, dsdt->length);
+
+	/* Fill in platform-specific global NVS variables */
+	acpi_create_gnvs((struct acpi_global_nvs *)current);
+	current += sizeof(struct acpi_global_nvs);
+	current = ALIGN(current, 16);
+
 	debug("ACPI:    * FADT\n");
 	fadt = (struct acpi_fadt *)current;
 	current += sizeof(struct acpi_fadt);

doc/README.x86

@@ -1020,8 +1020,6 @@ Features not supported so far (to make it a complete ACPI solution):
  * S3 (Suspend to RAM), S4 (Suspend to Disk).
 
 Features that are optional:
- * ACPI global NVS support. We may need it to simplify ASL code logic if
-   utilizing NVS variables. Most likely we will need this sooner or later.
  * Dynamic AML bytecodes insertion at run-time. We may need this to support
    SSDT table generation and DSDT fix up.
  * SMI support. Since U-Boot is a modern bootloader, we don't want to bring