x86: Generate a valid ACPI table

Implement write_acpi_table() to create a minimal working ACPI table.
This includes writing FACS, XSDT, RSDP, FADT, MCFG, MADT, DSDT & SSDT
ACPI table entries.

Use a Kconfig option GENERATE_ACPI_TABLE to tell U-Boot whether we need
actually write the APCI table just like we did for PIRQ routing, MP table
and SFI tables. With ACPI table existence, linux kernel gets control of
power management, thermal management, configuration management and
monitoring in hardware.

Signed-off-by: Saket Sinha <saket.sinha89@gmail.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tidied up whitespace and aligned some tabs:
Signed-off-by: Simon Glass <sjg@chromium.org>

6 files changed, 855 insertions, 0 deletions

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 273f08f52dd..5e42d7d6a73 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -349,6 +349,15 @@ config GENERATE_MP_TABLE
 	  multiprocessing as well as symmetric I/O interrupt handling with
 	  the local APIC and I/O APIC.
 
+config GENERATE_ACPI_TABLE
+	bool "Generate an ACPI (Advanced Configuration and Power Interface) table"
+	default n
+	help
+	  The Advanced Configuration and Power Interface (ACPI) specification
+	  provides an open standard for device configuration and management
+	  by the operating system. It defines platform-independent interfaces
+	  for configuration and power management monitoring.
+
 endmenu
 
 config MAX_PIRQ_LINKS
diff --git a/arch/x86/include/asm/acpi_table.h b/arch/x86/include/asm/acpi_table.h
new file mode 100644
index 00000000000..0853248f807
--- /dev/null
+++ b/arch/x86/include/asm/acpi_table.h
@@ -0,0 +1,393 @@
+/*
+ * Based on acpi.c from coreboot
+ *
+ * Copyright (C) 2015, Saket Sinha <saket.sinha89@gmail.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <malloc.h>
+#include <asm/post.h>
+#include <linux/string.h>
+
+#define RSDP_SIG		"RSD PTR "	/* RSDT pointer signature */
+#define ACPI_TABLE_CREATOR	"UBOOT   "	/* Must be 8 bytes long! */
+#define OEM_ID			"UBOOT "	/* Must be 6 bytes long! */
+#define ASLC			"INTL"		/* Must be 4 bytes long! */
+
+#define OEM_REVISION	42
+#define ASL_COMPILER_REVISION	42
+
+/* IO ports to generate SMIs */
+#define APM_CNT			0xb2
+#define APM_CNT_CST_CONTROL	0x85
+#define APM_CNT_PST_CONTROL	0x80
+#define APM_CNT_ACPI_DISABLE	0x1e
+#define APM_CNT_ACPI_ENABLE	0xe1
+#define APM_CNT_MBI_UPDATE	0xeb
+#define APM_CNT_GNVS_UPDATE	0xea
+#define APM_CNT_FINALIZE	0xcb
+#define APM_CNT_LEGACY		0xcc
+#define APM_ST			0xb3
+
+/* Multiple Processor Interrupts */
+#define MP_IRQ_POLARITY_DEFAULT	0x0
+#define MP_IRQ_POLARITY_HIGH	0x1
+#define MP_IRQ_POLARITY_LOW	0x3
+#define MP_IRQ_POLARITY_MASK	0x3
+#define MP_IRQ_TRIGGER_DEFAULT	0x0
+#define MP_IRQ_TRIGGER_EDGE	0x4
+#define MP_IRQ_TRIGGER_LEVEL	0xc
+#define MP_IRQ_TRIGGER_MASK	0xc
+
+/*
+ * Interrupt assigned for SCI in order to
+ * create the ACPI MADT IRQ override entry
+ */
+#define ACTL		0x00
+#define SCIS_MASK	0x07
+#define SCIS_IRQ9	0x00
+#define SCIS_IRQ10	0x01
+#define SCIS_IRQ11	0x02
+#define SCIS_IRQ20	0x04
+#define SCIS_IRQ21	0x05
+#define SCIS_IRQ22	0x06
+#define SCIS_IRQ23	0x07
+
+#define ACPI_REV_ACPI_1_0	1
+#define ACPI_REV_ACPI_2_0	1
+#define ACPI_REV_ACPI_3_0	2
+#define ACPI_REV_ACPI_4_0	3
+#define ACPI_REV_ACPI_5_0	5
+
+#define ACPI_RSDP_REV_ACPI_1_0	0
+#define ACPI_RSDP_REV_ACPI_2_0	2
+
+typedef struct acpi_gen_regaddr {
+	u8  space_id;	/* Address space ID */
+	u8  bit_width;	/* Register size in bits */
+	u8  bit_offset;	/* Register bit offset */
+	union {
+		/* Reserved in ACPI 2.0 - 2.0b */
+		u8  resv;
+		/* Access size in ACPI 2.0c/3.0/4.0/5.0 */
+		u8  access_size;
+	};
+	u32 addrl;	/* Register address, low 32 bits */
+	u32 addrh;	/* Register address, high 32 bits */
+} acpi_addr_t;
+
+
+/*
+ * RSDP (Root System Description Pointer)
+ * Note: ACPI 1.0 didn't have length, xsdt_address, and ext_checksum
+ */
+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 */
+	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];
+};
+
+enum acpi_address_space_type {
+	ACPI_ADDRESS_SPACE_MEMORY = 0,	/* System memory */
+	ACPI_ADDRESS_SPACE_IO,		/* System I/O */
+	ACPI_ADDRESS_SPACE_PCI,		/* PCI config space */
+	ACPI_ADDRESS_SPACE_EC,		/* Embedded controller */
+	ACPI_ADDRESS_SPACE_SMBUS,	/* SMBus */
+	ACPI_ADDRESS_SPACE_PCC = 0x0a,	/* Platform Comm. Channel */
+	ACPI_ADDRESS_SPACE_FIXED = 0x7f	/* Functional fixed hardware */
+};
+
+/* functional fixed hardware */
+#define ACPI_FFIXEDHW_VENDOR_INTEL	1	/* Intel */
+#define ACPI_FFIXEDHW_CLASS_HLT		0	/* C1 Halt */
+#define ACPI_FFIXEDHW_CLASS_IO_HLT	1	/* C1 I/O then Halt */
+#define ACPI_FFIXEDHW_CLASS_MWAIT	2	/* MWAIT Native C-state */
+#define ACPI_FFIXEDHW_FLAG_HW_COORD	1	/* Hardware Coordination bit */
+#define ACPI_FFIXEDHW_FLAG_BM_STS	2	/* BM_STS avoidance bit */
+
+/* Access size definitions for Generic address structure */
+enum acpi_address_space_size {
+	ACPI_ACCESS_SIZE_UNDEFINED = 0,	/* Undefined (legacy reasons) */
+	ACPI_ACCESS_SIZE_BYTE_ACCESS = 1,
+	ACPI_ACCESS_SIZE_WORD_ACCESS = 2,
+	ACPI_ACCESS_SIZE_DWORD_ACCESS = 3,
+	ACPI_ACCESS_SIZE_QWORD_ACCESS = 4
+};
+
+/* Generic ACPI header, provided by (almost) all tables */
+typedef struct acpi_table_header {
+	char signature[4];	/* ACPI signature (4 ASCII characters) */
+	u32 length;		/* Table length in bytes (incl. header) */
+	u8 revision;		/* Table version (not ACPI version!) */
+	volatile u8 checksum;	/* To make sum of entire table == 0 */
+	char oem_id[6];		/* OEM identification */
+	char oem_table_id[8];	/* OEM table identification */
+	u32 oem_revision;	/* OEM revision number */
+	char asl_compiler_id[4]; /* ASL compiler vendor ID */
+	u32 asl_compiler_revision; /* ASL compiler revision number */
+} acpi_header_t;
+
+/* A maximum number of 32 ACPI tables ought to be enough for now */
+#define MAX_ACPI_TABLES	32
+
+/* RSDT (Root System Description Table) */
+struct acpi_rsdt {
+	struct acpi_table_header header;
+	u32 entry[MAX_ACPI_TABLES];
+};
+
+/* XSDT (Extended System Description Table) */
+struct acpi_xsdt {
+	struct acpi_table_header header;
+	u64 entry[MAX_ACPI_TABLES];
+};
+
+/* MCFG (PCI Express MMIO config space BAR description table) */
+struct acpi_mcfg {
+	struct acpi_table_header header;
+	u8 reserved[8];
+};
+
+struct acpi_mcfg_mmconfig {
+	u32 base_address;
+	u32 base_reserved;
+	u16 pci_segment_group_number;
+	u8 start_bus_number;
+	u8 end_bus_number;
+	u8 reserved[4];
+};
+
+/* MADT (Multiple APIC Description Table) */
+struct acpi_madt {
+	struct acpi_table_header header;
+	u32 lapic_addr;			/* Local APIC address */
+	u32 flags;			/* Multiple APIC flags */
+} acpi_madt_t;
+
+enum dev_scope_type {
+	SCOPE_PCI_ENDPOINT = 1,
+	SCOPE_PCI_SUB = 2,
+	SCOPE_IOAPIC = 3,
+	SCOPE_MSI_HPET = 4
+};
+
+typedef struct dev_scope {
+	u8 type;
+	u8 length;
+	u8 reserved[2];
+	u8 enumeration;
+	u8 start_bus;
+	struct {
+		u8 dev;
+		u8 fn;
+	} path[0];
+} __packed dev_scope_t;
+
+/* MADT: APIC Structure Type*/
+enum acpi_apic_types {
+	LOCALAPIC	= 0,	/* Processor local APIC */
+	IOAPIC,			/* I/O APIC */
+	IRQSOURCEOVERRIDE,	/* Interrupt source override */
+	NMITYPE,		/* NMI source */
+	LOCALNMITYPE, 		/* Local APIC NMI */
+	LAPICADDRESSOVERRIDE,	/* Local APIC address override */
+	IOSAPIC,		/* I/O SAPIC */
+	LOCALSAPIC,		/* Local SAPIC */
+	PLATFORMIRQSOURCES,	/* Platform interrupt sources */
+	LOCALX2SAPIC,		/* Processor local x2APIC */
+	LOCALX2APICNMI,		/* Local x2APIC NMI */
+};
+
+/* MADT: Processor Local APIC Structure */
+struct acpi_madt_lapic {
+	u8 type;		/* Type (0) */
+	u8 length;		/* Length in bytes (8) */
+	u8 processor_id;	/* ACPI processor ID */
+	u8 apic_id;		/* Local APIC ID */
+	u32 flags;		/* Local APIC flags */
+};
+
+#define LOCAL_APIC_FLAG_ENABLED	(1 << 0)
+/* bits 1-31: reserved */
+#define PCAT_COMPAT		(1 << 0)
+/* bits 1-31: reserved */
+
+/* MADT: Local APIC NMI Structure */
+struct acpi_madt_lapic_nmi {
+	u8 type;		/* Type (4) */
+	u8 length;		/* Length in bytes (6) */
+	u8 processor_id;	/* ACPI processor ID */
+	u16 flags;		/* MPS INTI flags */
+	u8 lint;		/* Local APIC LINT# */
+};
+
+/* MADT: I/O APIC Structure */
+struct acpi_madt_ioapic {
+	u8 type;		/* Type (1) */
+	u8 length;		/* Length in bytes (12) */
+	u8 ioapic_id;		/* I/O APIC ID */
+	u8 reserved;
+	u32 ioapic_addr;	/* I/O APIC address */
+	u32 gsi_base;		/* Global system interrupt base */
+};
+
+/* MADT: Interrupt Source Override Structure */
+struct acpi_madt_irqoverride {
+	u8 type;		/* Type (2) */
+	u8 length;		/* Length in bytes (10) */
+	u8 bus;			/* ISA (0) */
+	u8 source;		/* Bus-relative int. source (IRQ) */
+	u32 gsirq;		/* Global system interrupt */
+	u16 flags;		/* MPS INTI flags */
+};
+
+/* FADT (Fixed ACPI Description Table) */
+struct __packed acpi_fadt {
+	struct acpi_table_header header;
+	u32 firmware_ctrl;
+	u32 dsdt;
+	u8 model;
+	u8 preferred_pm_profile;
+	u16 sci_int;
+	u32 smi_cmd;
+	u8 acpi_enable;
+	u8 acpi_disable;
+	u8 s4bios_req;
+	u8 pstate_cnt;
+	u32 pm1a_evt_blk;
+	u32 pm1b_evt_blk;
+	u32 pm1a_cnt_blk;
+	u32 pm1b_cnt_blk;
+	u32 pm2_cnt_blk;
+	u32 pm_tmr_blk;
+	u32 gpe0_blk;
+	u32 gpe1_blk;
+	u8 pm1_evt_len;
+	u8 pm1_cnt_len;
+	u8 pm2_cnt_len;
+	u8 pm_tmr_len;
+	u8 gpe0_blk_len;
+	u8 gpe1_blk_len;
+	u8 gpe1_base;
+	u8 cst_cnt;
+	u16 p_lvl2_lat;
+	u16 p_lvl3_lat;
+	u16 flush_size;
+	u16 flush_stride;
+	u8 duty_offset;
+	u8 duty_width;
+	u8 day_alrm;
+	u8 mon_alrm;
+	u8 century;
+	u16 iapc_boot_arch;
+	u8 res2;
+	u32 flags;
+	struct acpi_gen_regaddr reset_reg;
+	u8 reset_value;
+	u8 res3;
+	u8 res4;
+	u8 res5;
+	u32 x_firmware_ctl_l;
+	u32 x_firmware_ctl_h;
+	u32 x_dsdt_l;
+	u32 x_dsdt_h;
+	struct acpi_gen_regaddr x_pm1a_evt_blk;
+	struct acpi_gen_regaddr x_pm1b_evt_blk;
+	struct acpi_gen_regaddr x_pm1a_cnt_blk;
+	struct acpi_gen_regaddr x_pm1b_cnt_blk;
+	struct acpi_gen_regaddr x_pm2_cnt_blk;
+	struct acpi_gen_regaddr x_pm_tmr_blk;
+	struct acpi_gen_regaddr x_gpe0_blk;
+	struct acpi_gen_regaddr x_gpe1_blk;
+};
+
+/* Flags for p_lvl2_lat and p_lvl3_lat */
+#define ACPI_FADT_C2_NOT_SUPPORTED	101
+#define ACPI_FADT_C3_NOT_SUPPORTED	1001
+
+/* FADT Feature Flags */
+#define ACPI_FADT_WBINVD		(1 << 0)
+#define ACPI_FADT_WBINVD_FLUSH		(1 << 1)
+#define ACPI_FADT_C1_SUPPORTED		(1 << 2)
+#define ACPI_FADT_C2_MP_SUPPORTED	(1 << 3)
+#define ACPI_FADT_POWER_BUTTON		(1 << 4)
+#define ACPI_FADT_SLEEP_BUTTON		(1 << 5)
+#define ACPI_FADT_FIXED_RTC		(1 << 6)
+#define ACPI_FADT_S4_RTC_WAKE		(1 << 7)
+#define ACPI_FADT_32BIT_TIMER		(1 << 8)
+#define ACPI_FADT_DOCKING_SUPPORTED	(1 << 9)
+#define ACPI_FADT_RESET_REGISTER	(1 << 10)
+#define ACPI_FADT_SEALED_CASE		(1 << 11)
+#define ACPI_FADT_HEADLESS		(1 << 12)
+#define ACPI_FADT_SLEEP_TYPE		(1 << 13)
+#define ACPI_FADT_PCI_EXPRESS_WAKE	(1 << 14)
+#define ACPI_FADT_PLATFORM_CLOCK	(1 << 15)
+#define ACPI_FADT_S4_RTC_VALID		(1 << 16)
+#define ACPI_FADT_REMOTE_POWER_ON	(1 << 17)
+#define ACPI_FADT_APIC_CLUSTER		(1 << 18)
+#define ACPI_FADT_APIC_PHYSICAL		(1 << 19)
+/* 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 */
+
+/* FADT Boot Architecture Flags */
+#define ACPI_FADT_LEGACY_DEVICES	(1 << 0)
+#define ACPI_FADT_8042			(1 << 1)
+#define ACPI_FADT_VGA_NOT_PRESENT	(1 << 2)
+#define ACPI_FADT_MSI_NOT_SUPPORTED	(1 << 3)
+#define ACPI_FADT_NO_PCIE_ASPM_CONTROL	(1 << 4)
+/* No legacy devices (including 8042) */
+#define ACPI_FADT_LEGACY_FREE		0x00
+
+/* FADT Preferred Power Management Profile */
+#define PM_UNSPECIFIED		0
+#define PM_DESKTOP		1
+#define PM_MOBILE		2
+#define PM_WORKSTATION		3
+#define PM_ENTERPRISE_SERVER	4
+#define PM_SOHO_SERVER		5
+#define PM_APPLIANCE_PC		6
+#define PM_PERFORMANCE_SERVER	7
+#define PM_TABLET		8	/* ACPI 5.0 */
+
+/* FACS (Firmware ACPI Control Structure) */
+struct acpi_facs {
+	char signature[4];			/* "FACS" */
+	u32 length;				/* Length in bytes (>= 64) */
+	u32 hardware_signature;			/* Hardware signature */
+	u32 firmware_waking_vector;		/* Firmware waking vector */
+	u32 global_lock;			/* Global lock */
+	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 4.0: 2 */
+	u8 resv[31];				/* FIXME: 4.0: ospm_flags */
+};
+
+/* FACS flags */
+#define ACPI_FACS_S4BIOS_F	(1 << 0)
+#define ACPI_FACS_64BIT_WAKE_F	(1 << 1)
+/* Bits 31..2: reserved */
+
+/* These can be used by the target port */
+
+unsigned long acpi_create_madt_lapics(unsigned long current);
+int acpi_create_madt_ioapic(struct acpi_madt_ioapic *ioapic, u8 id, u32 addr,
+			 u32 gsi_base);
+int acpi_create_madt_irqoverride(struct acpi_madt_irqoverride *irqoverride,
+			 u8 bus, u8 source, u32 gsirq, u16 flags);
+unsigned long acpi_fill_madt(unsigned long current);
+void acpi_create_fadt(struct acpi_fadt *fadt, struct acpi_facs *facs,
+			 void *dsdt);
+int acpi_create_madt_lapic_nmi(struct acpi_madt_lapic_nmi *lapic_nmi, u8 cpu,
+			 u16 flags, u8 lint);
+unsigned long write_acpi_tables(unsigned long start);
diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile
index dcfe9ee85c5..6ecd6dbd9d2 100644
--- a/arch/x86/lib/Makefile
+++ b/arch/x86/lib/Makefile
@@ -30,6 +30,7 @@ obj-y += physmem.o
 obj-$(CONFIG_X86_RAMTEST) += ramtest.o
 obj-y += sfi.o
 obj-y	+= string.o
+obj-$(CONFIG_GENERATE_ACPI_TABLE) += acpi_table.o
 obj-y	+= tables.o
 obj-$(CONFIG_SYS_X86_TSC_TIMER)	+= tsc_timer.o
 obj-$(CONFIG_CMD_ZBOOT)	+= zimage.o
diff --git a/arch/x86/lib/acpi_table.c b/arch/x86/lib/acpi_table.c
new file mode 100644
index 00000000000..ab1db7ec26e
--- /dev/null
+++ b/arch/x86/lib/acpi_table.c
@@ -0,0 +1,436 @@
+/*
+ * Based on acpi.c from coreboot
+ *
+ * Copyright (C) 2015, Saket Sinha <saket.sinha89@gmail.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <cpu.h>
+#include <dm.h>
+#include <dm/uclass-internal.h>
+#include <dm/lists.h>
+#include <asm/acpi_table.h>
+#include <asm/cpu.h>
+#include <asm/ioapic.h>
+#include <asm/lapic.h>
+#include <asm/tables.h>
+#include <asm/pci.h>
+
+/*
+ * IASL compiles the dsdt entries and
+ * writes the hex values to AmlCode array.
+ * CamelCase cannot be handled here.
+ */
+extern const unsigned char AmlCode[];
+
+/**
+* Add an ACPI table to the RSDT (and XSDT) structure, recalculate length
+* and checksum.
+*/
+static void acpi_add_table(struct acpi_rsdp *rsdp, void *table)
+{
+	int i, entries_num;
+	struct acpi_rsdt *rsdt;
+	struct acpi_xsdt *xsdt = NULL;
+
+	/* The RSDT is mandatory while the XSDT is not */
+	rsdt = (struct acpi_rsdt *)rsdp->rsdt_address;
+
+	if (rsdp->xsdt_address)
+		xsdt = (struct acpi_xsdt *)((u32)rsdp->xsdt_address);
+
+	/* This should always be MAX_ACPI_TABLES */
+	entries_num = ARRAY_SIZE(rsdt->entry);
+
+	for (i = 0; i < entries_num; i++) {
+		if (rsdt->entry[i] == 0)
+			break;
+	}
+
+	if (i >= entries_num) {
+		debug("ACPI: Error: too many tables.\n");
+		return;
+	}
+
+	/* Add table to the RSDT */
+	rsdt->entry[i] = (u32)table;
+
+	/* Fix RSDT length or the kernel will assume invalid entries */
+	rsdt->header.length = sizeof(acpi_header_t) + (sizeof(u32) * (i + 1));
+
+	/* Re-calculate checksum */
+	rsdt->header.checksum = 0;
+	rsdt->header.checksum = table_compute_checksum((u8 *)rsdt,
+						       rsdt->header.length);
+
+	/*
+	 * And now the same thing for the XSDT. We use the same index as for
+	 * now we want the XSDT and RSDT to always be in sync in U-Boot
+	 */
+	if (xsdt) {
+		/* Add table to the XSDT */
+		xsdt->entry[i] = (u64)(u32)table;
+
+		/* Fix XSDT length */
+		xsdt->header.length = sizeof(acpi_header_t) +
+			 (sizeof(u64) * (i + 1));
+
+		/* Re-calculate checksum */
+		xsdt->header.checksum = 0;
+		xsdt->header.checksum = table_compute_checksum((u8 *)xsdt,
+				xsdt->header.length);
+	}
+}
+
+static int acpi_create_madt_lapic(struct acpi_madt_lapic *lapic,
+			 u8 cpu, u8 apic)
+{
+	lapic->type = LOCALAPIC; /* Local APIC structure */
+	lapic->length = sizeof(struct acpi_madt_lapic);
+	lapic->flags = LOCAL_APIC_FLAG_ENABLED; /* Processor/LAPIC enabled */
+	lapic->processor_id = cpu;
+	lapic->apic_id = apic;
+
+	return lapic->length;
+}
+
+unsigned long acpi_create_madt_lapics(unsigned long current)
+{
+	struct udevice *dev;
+
+	for (uclass_find_first_device(UCLASS_CPU, &dev);
+	     dev;
+	     uclass_find_next_device(&dev)) {
+		struct cpu_platdata *plat = dev_get_parent_platdata(dev);
+
+		current += acpi_create_madt_lapic(
+			(struct acpi_madt_lapic *)current,
+			plat->cpu_id, plat->cpu_id);
+		}
+		return current;
+}
+
+int acpi_create_madt_ioapic(struct acpi_madt_ioapic *ioapic, u8 id, u32 addr,
+			 u32 gsi_base)
+{
+	ioapic->type = IOAPIC;
+	ioapic->length = sizeof(struct acpi_madt_ioapic);
+	ioapic->reserved = 0x00;
+	ioapic->gsi_base = gsi_base;
+	ioapic->ioapic_id = id;
+	ioapic->ioapic_addr = addr;
+
+	return ioapic->length;
+}
+
+int acpi_create_madt_irqoverride(struct acpi_madt_irqoverride *irqoverride,
+			 u8 bus, u8 source, u32 gsirq, u16 flags)
+{
+	irqoverride->type = IRQSOURCEOVERRIDE;
+	irqoverride->length = sizeof(struct acpi_madt_irqoverride);
+	irqoverride->bus = bus;
+	irqoverride->source = source;
+	irqoverride->gsirq = gsirq;
+	irqoverride->flags = flags;
+
+	return irqoverride->length;
+}
+
+int acpi_create_madt_lapic_nmi(struct acpi_madt_lapic_nmi *lapic_nmi,
+			 u8 cpu, u16 flags, u8 lint)
+{
+	lapic_nmi->type = LOCALNMITYPE;
+	lapic_nmi->length = sizeof(struct acpi_madt_lapic_nmi);
+	lapic_nmi->flags = flags;
+	lapic_nmi->processor_id = cpu;
+	lapic_nmi->lint = lint;
+
+	return lapic_nmi->length;
+}
+
+static void fill_header(acpi_header_t *header, char *signature, int length)
+{
+	memcpy(header->signature, signature, length);
+	memcpy(header->oem_id, OEM_ID, 6);
+	memcpy(header->oem_table_id, ACPI_TABLE_CREATOR, 8);
+	memcpy(header->asl_compiler_id, ASLC, 4);
+}
+
+static void acpi_create_madt(struct acpi_madt *madt)
+{
+	acpi_header_t *header = &(madt->header);
+	unsigned long current = (unsigned long)madt + sizeof(struct acpi_madt);
+
+	memset((void *)madt, 0, sizeof(struct acpi_madt));
+
+	/* Fill out header fields */
+	fill_header(header, "APIC", 4);
+	header->length = sizeof(struct acpi_madt);
+
+	/* ACPI 1.0/2.0: 1, ACPI 3.0: 2, ACPI 4.0: 3 */
+	header->revision = ACPI_REV_ACPI_2_0;
+
+	madt->lapic_addr = LAPIC_DEFAULT_BASE;
+	madt->flags = PCAT_COMPAT;
+
+	current = acpi_fill_madt(current);
+
+	/* (Re)calculate length and checksum */
+	header->length = current - (unsigned long)madt;
+
+	header->checksum = table_compute_checksum((void *)madt, header->length);
+}
+
+static int acpi_create_mcfg_mmconfig(struct acpi_mcfg_mmconfig *mmconfig,
+			 u32 base, u16 seg_nr, u8 start, u8 end)
+{
+	memset(mmconfig, 0, sizeof(*mmconfig));
+	mmconfig->base_address = base;
+	mmconfig->base_reserved = 0;
+	mmconfig->pci_segment_group_number = seg_nr;
+	mmconfig->start_bus_number = start;
+	mmconfig->end_bus_number = end;
+
+	return sizeof(struct acpi_mcfg_mmconfig);
+}
+
+static unsigned long acpi_fill_mcfg(unsigned long current)
+{
+	current += acpi_create_mcfg_mmconfig
+		((struct acpi_mcfg_mmconfig *)current,
+		 CONFIG_PCIE_ECAM_BASE, 0x0, 0x0, 255);
+
+	return current;
+}
+
+/* MCFG is defined in the PCI Firmware Specification 3.0 */
+static void acpi_create_mcfg(struct acpi_mcfg *mcfg)
+{
+	acpi_header_t *header = &(mcfg->header);
+	unsigned long current = (unsigned long)mcfg + sizeof(struct acpi_mcfg);
+
+	memset((void *)mcfg, 0, sizeof(struct acpi_mcfg));
+
+	/* Fill out header fields */
+	fill_header(header, "MCFG", 4);
+	header->length = sizeof(struct acpi_mcfg);
+
+	/* ACPI 1.0/2.0: 1, ACPI 3.0: 2, ACPI 4.0: 3 */
+	header->revision = ACPI_REV_ACPI_2_0;
+
+	current = acpi_fill_mcfg(current);
+
+	/* (Re)calculate length and checksum */
+	header->length = current - (unsigned long)mcfg;
+	header->checksum = table_compute_checksum((void *)mcfg, header->length);
+}
+
+static void acpi_create_facs(struct acpi_facs *facs)
+{
+	memset((void *)facs, 0, sizeof(struct acpi_facs));
+
+	memcpy(facs->signature, "FACS", 4);
+	facs->length = sizeof(struct acpi_facs);
+	facs->hardware_signature = 0;
+	facs->firmware_waking_vector = 0;
+	facs->global_lock = 0;
+	facs->flags = 0;
+	facs->x_firmware_waking_vector_l = 0;
+	facs->x_firmware_waking_vector_h = 0;
+	facs->version = 1; /* ACPI 1.0: 0, ACPI 2.0/3.0: 1, ACPI 4.0: 2 */
+}
+
+static void acpi_write_rsdt(struct acpi_rsdt *rsdt)
+{
+	acpi_header_t *header = &(rsdt->header);
+
+	/* Fill out header fields */
+	fill_header(header, "RSDT", 4);
+	header->length = sizeof(struct acpi_rsdt);
+
+	/* ACPI 1.0/2.0: 1, ACPI 3.0: 2, ACPI 4.0: 3 */
+	header->revision = ACPI_REV_ACPI_2_0;
+
+	/* Entries are filled in later, we come with an empty set */
+
+	/* Fix checksum */
+	header->checksum = table_compute_checksum((void *)rsdt,
+			sizeof(struct acpi_rsdt));
+}
+
+static void acpi_write_xsdt(struct acpi_xsdt *xsdt)
+{
+	acpi_header_t *header = &(xsdt->header);
+
+	/* Fill out header fields */
+	fill_header(header, "XSDT", 4);
+	header->length = sizeof(struct acpi_xsdt);
+
+	/* ACPI 1.0/2.0: 1, ACPI 3.0: 2, ACPI 4.0: 3 */
+	header->revision = ACPI_REV_ACPI_2_0;
+
+	/* Entries are filled in later, we come with an empty set */
+
+	/* Fix checksum */
+	header->checksum = table_compute_checksum((void *)xsdt,
+			sizeof(struct acpi_xsdt));
+}
+
+static void acpi_write_rsdp(struct acpi_rsdp *rsdp, struct acpi_rsdt *rsdt,
+			 struct acpi_xsdt *xsdt)
+{
+	memset(rsdp, 0, sizeof(struct acpi_rsdp));
+
+	memcpy(rsdp->signature, RSDP_SIG, 8);
+	memcpy(rsdp->oem_id, OEM_ID, 6);
+
+	rsdp->length = sizeof(struct acpi_rsdp);
+	rsdp->rsdt_address = (u32)rsdt;
+
+	/*
+	* Revision: ACPI 1.0: 0, ACPI 2.0/3.0/4.0: 2
+	*
+	* Some OSes expect an XSDT to be present for RSD PTR revisions >= 2.
+	* If we don't have an ACPI XSDT, force ACPI 1.0 (and thus RSD PTR
+	* revision 0)
+	*/
+	if (xsdt == NULL) {
+		rsdp->revision = ACPI_RSDP_REV_ACPI_1_0;
+	} else {
+		rsdp->xsdt_address = (u64)(u32)xsdt;
+		rsdp->revision = ACPI_RSDP_REV_ACPI_2_0;
+	}
+
+	/* Calculate checksums */
+	rsdp->checksum = table_compute_checksum((void *)rsdp, 20);
+	rsdp->ext_checksum = table_compute_checksum((void *)rsdp,
+			sizeof(struct acpi_rsdp));
+}
+
+static void acpi_create_ssdt_generator(acpi_header_t *ssdt,
+			 const char *oem_table_id)
+{
+	unsigned long current = (unsigned long)ssdt + sizeof(acpi_header_t);
+
+	memset((void *)ssdt, 0, sizeof(acpi_header_t));
+
+	memcpy(&ssdt->signature, "SSDT", 4);
+	/* Access size in ACPI 2.0c/3.0/4.0/5.0 */
+	ssdt->revision = ACPI_REV_ACPI_3_0;
+	memcpy(&ssdt->oem_id, OEM_ID, 6);
+	memcpy(&ssdt->oem_table_id, oem_table_id, 8);
+	ssdt->oem_revision = OEM_REVISION;
+	memcpy(&ssdt->asl_compiler_id, ASLC, 4);
+	ssdt->asl_compiler_revision = ASL_COMPILER_REVISION;
+	ssdt->length = sizeof(acpi_header_t);
+
+	/* (Re)calculate length and checksum */
+	ssdt->length = current - (unsigned long)ssdt;
+	ssdt->checksum = table_compute_checksum((void *)ssdt, ssdt->length);
+}
+
+unsigned long write_acpi_tables(unsigned long start)
+{
+	unsigned long current;
+	struct acpi_rsdp *rsdp;
+	struct acpi_rsdt *rsdt;
+	struct acpi_xsdt *xsdt;
+	struct acpi_facs *facs;
+	acpi_header_t *dsdt;
+	struct acpi_fadt *fadt;
+	struct acpi_mcfg *mcfg;
+	struct acpi_madt *madt;
+	acpi_header_t *ssdt;
+
+	current = start;
+
+	/* Align ACPI tables to 16byte */
+	current = ALIGN(current, 16);
+
+	debug("ACPI: Writing ACPI tables at %lx.\n", start);
+
+	/* We need at least an RSDP and an RSDT Table */
+	rsdp = (struct acpi_rsdp *)current;
+	current += sizeof(struct acpi_rsdp);
+	current = ALIGN(current, 16);
+	rsdt = (struct acpi_rsdt *)current;
+	current += sizeof(struct acpi_rsdt);
+	current = ALIGN(current, 16);
+	xsdt = (struct acpi_xsdt *)current;
+	current += sizeof(struct acpi_xsdt);
+	current = ALIGN(current, 16);
+
+	/* clear all table memory */
+	memset((void *)start, 0, current - start);
+
+	acpi_write_rsdp(rsdp, rsdt, xsdt);
+	acpi_write_rsdt(rsdt);
+	acpi_write_xsdt(xsdt);
+
+	debug("ACPI:    * FACS\n");
+	facs = (struct acpi_facs *)current;
+	current += sizeof(struct acpi_facs);
+	current = ALIGN(current, 16);
+
+	acpi_create_facs(facs);
+
+	debug("ACPI:    * DSDT\n");
+	dsdt = (acpi_header_t *)current;
+	memcpy(dsdt, &AmlCode, sizeof(acpi_header_t));
+	if (dsdt->length >= sizeof(acpi_header_t)) {
+		current += sizeof(acpi_header_t);
+		memcpy((char *)current,
+				(char *)&AmlCode + sizeof(acpi_header_t),
+				dsdt->length - sizeof(acpi_header_t));
+		current += dsdt->length - sizeof(acpi_header_t);
+
+		/* (Re)calculate length and checksum */
+		dsdt->length = current - (unsigned long)dsdt;
+		dsdt->checksum = 0;
+		dsdt->checksum = table_compute_checksum((void *)dsdt,
+				dsdt->length);
+	}
+	current = ALIGN(current, 16);
+
+	debug("ACPI:    * FADT\n");
+	fadt = (struct acpi_fadt *)current;
+	current += sizeof(struct acpi_fadt);
+	current = ALIGN(current, 16);
+	acpi_create_fadt(fadt, facs, dsdt);
+	acpi_add_table(rsdp, fadt);
+
+	debug("ACPI:    * MCFG\n");
+	mcfg = (struct acpi_mcfg *)current;
+	acpi_create_mcfg(mcfg);
+	if (mcfg->header.length > sizeof(struct acpi_mcfg)) {
+		current += mcfg->header.length;
+		current = ALIGN(current, 16);
+		acpi_add_table(rsdp, mcfg);
+	}
+
+	debug("ACPI:    * MADT\n");
+	madt = (struct acpi_madt *)current;
+	acpi_create_madt(madt);
+	if (madt->header.length > sizeof(struct acpi_madt)) {
+		current += madt->header.length;
+		acpi_add_table(rsdp, madt);
+	}
+	current = ALIGN(current, 16);
+
+	debug("ACPI:    * SSDT\n");
+	ssdt = (acpi_header_t *)current;
+	acpi_create_ssdt_generator(ssdt, ACPI_TABLE_CREATOR);
+	if (ssdt->length > sizeof(acpi_header_t)) {
+		current += ssdt->length;
+		acpi_add_table(rsdp, ssdt);
+		current = ALIGN(current, 16);
+	}
+
+	debug("current = %lx\n", current);
+
+	debug("ACPI: done.\n");
+
+	return current;
+}
diff --git a/arch/x86/lib/tables.c b/arch/x86/lib/tables.c
index 75ffbc1b220..f15b2e2855a 100644
--- a/arch/x86/lib/tables.c
+++ b/arch/x86/lib/tables.c
@@ -8,6 +8,7 @@
 #include <asm/sfi.h>
 #include <asm/mpspec.h>
 #include <asm/tables.h>
+#include <asm/acpi_table.h>
 
 u8 table_compute_checksum(void *v, int len)
 {
@@ -51,4 +52,8 @@ void write_tables(void)
 	rom_table_end = write_mp_table(rom_table_end);
 	rom_table_end = ALIGN(rom_table_end, 1024);
 #endif
+#ifdef CONFIG_GENERATE_ACPI_TABLE
+	rom_table_end = write_acpi_tables(rom_table_end);
+	rom_table_end = ALIGN(rom_table_end, 1024);
+#endif
 }
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 1c949fc0eb9..ed30bf5bb96 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -297,6 +297,17 @@ $(obj)/%.dtb: $(src)/%.dts FORCE
 
 dtc-tmp = $(subst $(comma),_,$(dot-target).dts.tmp)
 
+# ACPI
+# ---------------------------------------------------------------------------
+quiet_cmd_acpi_c_asl= ASL     $@
+cmd_acpi_c_asl=         \
+	$(CPP) -x assembler-with-cpp -P -o $<.tmp $<; \
+	iasl -p $< -tc -va $<.tmp; \
+	mv $(patsubst %.asl,%.hex,$<) $@
+
+$(obj)/%.c:    $(src)/%.asl
+	$(call cmd,acpi_c_asl)
+
 # Bzip2
 # ---------------------------------------------------------------------------