ACPI: Refactor ChromeOS specific ACPI GNVS

The layout of GNVS has expectation for a fixed size
array for chromeos_acpi_t. This allows us to reduce
the exposure of <chromeos/gnvs.h>.

If chromeos_acpi_t was the last entry in struct global_nvs
padding at the end is also removed.

If device_nvs_t exists, place a properly sized reserve for
chromeos_acpi_t in the middle.

Allocation from cbmem is adjusted such that it matches exactly
the OperationRegion size defined inside the ASL.

Change-Id: If234075e11335ce958ce136dd3fe162f7e5afdf7
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/48788
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>

src/acpi/chromeos-gnvs.c

@@ -5,11 +5,9 @@
 #include <smbios.h>
 #include <vendorcode/google/chromeos/gnvs.h>
 
-void gnvs_assign_chromeos(void)
+void gnvs_assign_chromeos(void *gnvs_section)
 {
-	chromeos_acpi_t *gnvs_chromeos = gnvs_chromeos_ptr(acpi_get_gnvs());
-	if (!gnvs_chromeos)
-		return;
+	chromeos_acpi_t *gnvs_chromeos = gnvs_section;
 
 	chromeos_init_chromeos_acpi(gnvs_chromeos);
 
@@ -22,7 +20,7 @@ void gnvs_assign_chromeos(void)
 
 void gnvs_set_ecfw_rw(void)
 {
-	chromeos_acpi_t *gnvs_chromeos = gnvs_chromeos_ptr(acpi_get_gnvs());
+	chromeos_acpi_t *gnvs_chromeos = chromeos_get_chromeos_acpi();
 	if (!gnvs_chromeos)
 		return;
 
@@ -31,7 +29,7 @@ void gnvs_set_ecfw_rw(void)
 
 void smbios_type0_bios_version(uintptr_t address)
 {
-	chromeos_acpi_t *gnvs_chromeos = gnvs_chromeos_ptr(acpi_get_gnvs());
+	chromeos_acpi_t *gnvs_chromeos = chromeos_get_chromeos_acpi();
 	if (!gnvs_chromeos)
 		return;
 

src/acpi/gnvs.c

@@ -6,6 +6,7 @@
 #include <console/console.h>
 #include <string.h>
 #include <types.h>
+#include <vendorcode/google/chromeos/gnvs.h>
 
 static void *gnvs;
 
@@ -53,6 +54,14 @@ void *gnvs_get_or_create(void)
 	if (!gnvs_size)
 		return NULL;
 
+	/* Match with OpRegion declared in global_nvs.asl. */
+	if (gnvs_size < 0x100)
+		gnvs_size = 0x100;
+	if (gnvs_size > 0x1000)
+		gnvs_size = 0x2000;
+	else if (CONFIG(MAINBOARD_HAS_CHROMEOS))
+		gnvs_size = 0x1000;
+
 	gnvs = cbmem_add(CBMEM_ID_ACPI_GNVS, gnvs_size);
 	if (!gnvs)
 		return NULL;
@@ -63,7 +72,7 @@ void *gnvs_get_or_create(void)
 		gnvs_assign_cbmc();
 
 	if (CONFIG(CHROMEOS))
-		gnvs_assign_chromeos();
+		gnvs_assign_chromeos((u8 *)gnvs + GNVS_CHROMEOS_ACPI_OFFSET);
 
 	return gnvs;
 }

src/acpi/nvs.c

@@ -13,15 +13,3 @@ uint32_t *gnvs_cbmc_ptr(struct global_nvs *gnvs)
 {
 	return &gnvs->cbmc;
 }
-
-/* Some <soc/nvs.h> have no chromeos entry. */
-void *gnvs_chromeos_ptr(struct global_nvs *gnvs)
-{
-#if CONFIG(BOARD_EMULATION_QEMU_X86_Q35)
-	return NULL;
-#elif CONFIG(MAINBOARD_HAS_CHROMEOS)
-	return &gnvs->chromeos;
-#else
-	return NULL;
-#endif
-}