arch/x86/acpi: Clean up comments

As we are running ACPI v3.0, references to older
than v3.0 are removed.

Change-Id: I0cce0035ed2b952d59cc1a4a9e6017dae67ef6db
Signed-off-by: Elyes HAOUAS <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/c/31689
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>

1 files changed, 12 insertions, 20 deletions

diff --git a/src/arch/x86/include/arch/acpi.h b/src/arch/x86/include/arch/acpi.h
index aced58aa62..b3a5ce796a 100644
--- a/src/arch/x86/include/arch/acpi.h
+++ b/src/arch/x86/include/arch/acpi.h
@@ -90,14 +90,13 @@ typedef struct acpi_rsdp {
 	char  signature[8];	/* RSDP signature */
 	u8    checksum;		/* Checksum of the first 20 bytes */
 	char  oem_id[6];	/* OEM ID */
-	u8    revision;		/* 0 for ACPI 1.0, 2 for ACPI 2.0/3.0/4.0/6.2a */
+	u8    revision;		/* RSDP revision */
 	u32   rsdt_address;	/* Physical address of RSDT (32 bits) */
 	u32   length;		/* Total RSDP length (incl. extended part) */
 	u64   xsdt_address;	/* Physical address of XSDT (64 bits) */
 	u8    ext_checksum;	/* Checksum of the whole table */
 	u8    reserved[3];
 } __packed acpi_rsdp_t;
-/* Note: ACPI 1.0 didn't have length, xsdt_address, and ext_checksum. */
 
 /* GAS (Generic Address Structure) */
 typedef struct acpi_gen_regaddr {
@@ -106,9 +105,7 @@ typedef struct acpi_gen_regaddr {
 	u8  bit_offset;		/* Register bit offset */
 	union {
 		u8  resv;		/* Reserved in ACPI 2.0 - 2.0b */
-		u8  access_size;	/* Access size in
-					 * ACPI 2.0c/3.0/4.0/5.0/6.2a
-					 */
+		u8  access_size;	/* Access size since ACPI 2.0c */
 	};
 	u32 addrl;		/* Register address, low 32 bits */
 	u32 addrh;		/* Register address, high 32 bits */
@@ -484,11 +481,7 @@ typedef struct acpi_fadt {
 	struct acpi_table_header header;
 	u32 firmware_ctrl;
 	u32 dsdt;
-	u8 reserved;	/* Eliminated in ACPI 2.0. Platforms should set
-			 * this field to zero but field values of one
-			 * are also allowed to maintain compatibility
-			 * with ACPI 1.0.
-			 */
+	u8 reserved;	/* Should be 0 */
 	u8 preferred_pm_profile;
 	u16 sci_int;
 	u32 smi_cmd;
@@ -578,7 +571,7 @@ typedef struct acpi_fadt {
 /* Bits 20-31: reserved ACPI 3.0 & 4.0 */
 #define ACPI_FADT_HW_REDUCED_ACPI	(1 << 20)
 #define ACPI_FADT_LOW_PWR_IDLE_S0	(1 << 21)
-/* bits 22-31: reserved ACPI 5.0/6.2a */
+/* bits 22-31: reserved since ACPI 5.0 */
 
 /* FADT Boot Architecture Flags */
 #define ACPI_FADT_LEGACY_DEVICES	(1 << 0)
@@ -592,7 +585,7 @@ typedef struct acpi_fadt {
 /* FADT ARM Boot Architecture Flags */
 #define ACPI_FADT_ARM_PSCI_COMPLIANT	(1 << 0)
 #define ACPI_FADT_ARM_PSCI_USE_HVC	(1 << 1)
-/* bits 2-16: reserved ACPI 6.2a */
+/* bits 2-16: reserved since ACPI 5.1 */
 
 /* FADT Preferred Power Management Profile */
 enum acpi_preferred_pm_profiles {
@@ -604,7 +597,7 @@ enum acpi_preferred_pm_profiles {
 	PM_SOHO_SERVER		= 5,
 	PM_APPLIANCE_PC		= 6,
 	PM_PERFORMANCE_SERVER	= 7,
-	PM_TABLET		= 8,	/* ACPI 5.0/6.2a */
+	PM_TABLET		= 8,	/* ACPI 5.0 & greater */
 };
 
 /* FACS (Firmware ACPI Control Structure) */
@@ -617,10 +610,10 @@ typedef struct acpi_facs {
 	u32 flags;				/* FACS flags */
 	u32 x_firmware_waking_vector_l;		/* X FW waking vector, low */
 	u32 x_firmware_waking_vector_h;		/* X FW waking vector, high */
-	u8 version;				/* ACPI 6.2-A: 2 */
-	u8 resv1[3];				/* ACPI 6.2-A: 0 */
+	u8 version;				/* FACS version */
+	u8 resv1[3];				/* This value is 0 */
 	u32 ospm_flags;				/* 64BIT_WAKE_F */
-	u8 resv2[24];				/* ACPI 6.2-A: 0 */
+	u8 resv2[24];				/* This value is 0 */
 } __packed acpi_facs_t;
 
 /* FACS flags */
@@ -678,7 +671,7 @@ typedef struct acpi_bert {
 	u64 error_region;
 } __packed acpi_bert_t;
 
-/* Generic Error Data Entry (ACPI spec v6.2-A, table 382) */
+/* Generic Error Data Entry */
 typedef struct acpi_hest_generic_data {
 	guid_t section_type;
 	u32 error_severity;
@@ -691,7 +684,7 @@ typedef struct acpi_hest_generic_data {
 	/* error data */
 } __packed acpi_hest_generic_data_t;
 
-/* Generic Error Data Entry (ACPI spec v6.2-A, table 382) */
+/* Generic Error Data Entry v300 */
 typedef struct acpi_hest_generic_data_v300 {
 	guid_t section_type;
 	u32 error_severity;
@@ -717,7 +710,7 @@ typedef struct acpi_hest_generic_data_v300 {
 #define ACPI_GENERROR_VALID_FRUID_TEXT		BIT(1)
 #define ACPI_GENERROR_VALID_TIMESTAMP		BIT(2)
 
-/* Generic Error Status Block (ACPI spec v6.2-A, table 381) */
+/* Generic Error Status Block */
 typedef struct acpi_generic_error_status {
 	u32 block_status;
 	u32 raw_data_offset;	/* must follow any generic entries */
@@ -755,7 +748,6 @@ typedef struct acpi_tstate {
 
 /* Port types for ACPI _UPC object */
 enum acpi_upc_type {
-	/* These types are defined in ACPI 6.2 section 9.14 */
 	UPC_TYPE_A,
 	UPC_TYPE_MINI_AB,
 	UPC_TYPE_EXPRESSCARD,