v4.19.13 snapshot.
diff --git a/drivers/acpi/tables.c b/drivers/acpi/tables.c
new file mode 100644
index 0000000..a3d012b
--- /dev/null
+++ b/drivers/acpi/tables.c
@@ -0,0 +1,796 @@
+/*
+ * acpi_tables.c - ACPI Boot-Time Table Parsing
+ *
+ * Copyright (C) 2001 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ */
+
+/* Uncomment next line to get verbose printout */
+/* #define DEBUG */
+#define pr_fmt(fmt) "ACPI: " fmt
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/smp.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/irq.h>
+#include <linux/errno.h>
+#include <linux/acpi.h>
+#include <linux/bootmem.h>
+#include <linux/earlycpio.h>
+#include <linux/memblock.h>
+#include <linux/initrd.h>
+#include "internal.h"
+
+#ifdef CONFIG_ACPI_CUSTOM_DSDT
+#include CONFIG_ACPI_CUSTOM_DSDT_FILE
+#endif
+
+#define ACPI_MAX_TABLES 128
+
+static char *mps_inti_flags_polarity[] = { "dfl", "high", "res", "low" };
+static char *mps_inti_flags_trigger[] = { "dfl", "edge", "res", "level" };
+
+static struct acpi_table_desc initial_tables[ACPI_MAX_TABLES] __initdata;
+
+static int acpi_apic_instance __initdata;
+
+/*
+ * Disable table checksum verification for the early stage due to the size
+ * limitation of the current x86 early mapping implementation.
+ */
+static bool acpi_verify_table_checksum __initdata = false;
+
+void acpi_table_print_madt_entry(struct acpi_subtable_header *header)
+{
+ if (!header)
+ return;
+
+ switch (header->type) {
+
+ case ACPI_MADT_TYPE_LOCAL_APIC:
+ {
+ struct acpi_madt_local_apic *p =
+ (struct acpi_madt_local_apic *)header;
+ pr_debug("LAPIC (acpi_id[0x%02x] lapic_id[0x%02x] %s)\n",
+ p->processor_id, p->id,
+ (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
+ }
+ break;
+
+ case ACPI_MADT_TYPE_LOCAL_X2APIC:
+ {
+ struct acpi_madt_local_x2apic *p =
+ (struct acpi_madt_local_x2apic *)header;
+ pr_debug("X2APIC (apic_id[0x%02x] uid[0x%02x] %s)\n",
+ p->local_apic_id, p->uid,
+ (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
+ }
+ break;
+
+ case ACPI_MADT_TYPE_IO_APIC:
+ {
+ struct acpi_madt_io_apic *p =
+ (struct acpi_madt_io_apic *)header;
+ pr_debug("IOAPIC (id[0x%02x] address[0x%08x] gsi_base[%d])\n",
+ p->id, p->address, p->global_irq_base);
+ }
+ break;
+
+ case ACPI_MADT_TYPE_INTERRUPT_OVERRIDE:
+ {
+ struct acpi_madt_interrupt_override *p =
+ (struct acpi_madt_interrupt_override *)header;
+ pr_info("INT_SRC_OVR (bus %d bus_irq %d global_irq %d %s %s)\n",
+ p->bus, p->source_irq, p->global_irq,
+ mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
+ mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2]);
+ if (p->inti_flags &
+ ~(ACPI_MADT_POLARITY_MASK | ACPI_MADT_TRIGGER_MASK))
+ pr_info("INT_SRC_OVR unexpected reserved flags: 0x%x\n",
+ p->inti_flags &
+ ~(ACPI_MADT_POLARITY_MASK | ACPI_MADT_TRIGGER_MASK));
+ }
+ break;
+
+ case ACPI_MADT_TYPE_NMI_SOURCE:
+ {
+ struct acpi_madt_nmi_source *p =
+ (struct acpi_madt_nmi_source *)header;
+ pr_info("NMI_SRC (%s %s global_irq %d)\n",
+ mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
+ mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
+ p->global_irq);
+ }
+ break;
+
+ case ACPI_MADT_TYPE_LOCAL_APIC_NMI:
+ {
+ struct acpi_madt_local_apic_nmi *p =
+ (struct acpi_madt_local_apic_nmi *)header;
+ pr_info("LAPIC_NMI (acpi_id[0x%02x] %s %s lint[0x%x])\n",
+ p->processor_id,
+ mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK ],
+ mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
+ p->lint);
+ }
+ break;
+
+ case ACPI_MADT_TYPE_LOCAL_X2APIC_NMI:
+ {
+ u16 polarity, trigger;
+ struct acpi_madt_local_x2apic_nmi *p =
+ (struct acpi_madt_local_x2apic_nmi *)header;
+
+ polarity = p->inti_flags & ACPI_MADT_POLARITY_MASK;
+ trigger = (p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2;
+
+ pr_info("X2APIC_NMI (uid[0x%02x] %s %s lint[0x%x])\n",
+ p->uid,
+ mps_inti_flags_polarity[polarity],
+ mps_inti_flags_trigger[trigger],
+ p->lint);
+ }
+ break;
+
+ case ACPI_MADT_TYPE_LOCAL_APIC_OVERRIDE:
+ {
+ struct acpi_madt_local_apic_override *p =
+ (struct acpi_madt_local_apic_override *)header;
+ pr_info("LAPIC_ADDR_OVR (address[%p])\n",
+ (void *)(unsigned long)p->address);
+ }
+ break;
+
+ case ACPI_MADT_TYPE_IO_SAPIC:
+ {
+ struct acpi_madt_io_sapic *p =
+ (struct acpi_madt_io_sapic *)header;
+ pr_debug("IOSAPIC (id[0x%x] address[%p] gsi_base[%d])\n",
+ p->id, (void *)(unsigned long)p->address,
+ p->global_irq_base);
+ }
+ break;
+
+ case ACPI_MADT_TYPE_LOCAL_SAPIC:
+ {
+ struct acpi_madt_local_sapic *p =
+ (struct acpi_madt_local_sapic *)header;
+ pr_debug("LSAPIC (acpi_id[0x%02x] lsapic_id[0x%02x] lsapic_eid[0x%02x] %s)\n",
+ p->processor_id, p->id, p->eid,
+ (p->lapic_flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
+ }
+ break;
+
+ case ACPI_MADT_TYPE_INTERRUPT_SOURCE:
+ {
+ struct acpi_madt_interrupt_source *p =
+ (struct acpi_madt_interrupt_source *)header;
+ pr_info("PLAT_INT_SRC (%s %s type[0x%x] id[0x%04x] eid[0x%x] iosapic_vector[0x%x] global_irq[0x%x]\n",
+ mps_inti_flags_polarity[p->inti_flags & ACPI_MADT_POLARITY_MASK],
+ mps_inti_flags_trigger[(p->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2],
+ p->type, p->id, p->eid, p->io_sapic_vector,
+ p->global_irq);
+ }
+ break;
+
+ case ACPI_MADT_TYPE_GENERIC_INTERRUPT:
+ {
+ struct acpi_madt_generic_interrupt *p =
+ (struct acpi_madt_generic_interrupt *)header;
+ pr_debug("GICC (acpi_id[0x%04x] address[%llx] MPIDR[0x%llx] %s)\n",
+ p->uid, p->base_address,
+ p->arm_mpidr,
+ (p->flags & ACPI_MADT_ENABLED) ? "enabled" : "disabled");
+
+ }
+ break;
+
+ case ACPI_MADT_TYPE_GENERIC_DISTRIBUTOR:
+ {
+ struct acpi_madt_generic_distributor *p =
+ (struct acpi_madt_generic_distributor *)header;
+ pr_debug("GIC Distributor (gic_id[0x%04x] address[%llx] gsi_base[%d])\n",
+ p->gic_id, p->base_address,
+ p->global_irq_base);
+ }
+ break;
+
+ default:
+ pr_warn("Found unsupported MADT entry (type = 0x%x)\n",
+ header->type);
+ break;
+ }
+}
+
+/**
+ * acpi_parse_entries_array - for each proc_num find a suitable subtable
+ *
+ * @id: table id (for debugging purposes)
+ * @table_size: size of the root table
+ * @table_header: where does the table start?
+ * @proc: array of acpi_subtable_proc struct containing entry id
+ * and associated handler with it
+ * @proc_num: how big proc is?
+ * @max_entries: how many entries can we process?
+ *
+ * For each proc_num find a subtable with proc->id and run proc->handler
+ * on it. Assumption is that there's only single handler for particular
+ * entry id.
+ *
+ * The table_size is not the size of the complete ACPI table (the length
+ * field in the header struct), but only the size of the root table; i.e.,
+ * the offset from the very first byte of the complete ACPI table, to the
+ * first byte of the very first subtable.
+ *
+ * On success returns sum of all matching entries for all proc handlers.
+ * Otherwise, -ENODEV or -EINVAL is returned.
+ */
+static int __init
+acpi_parse_entries_array(char *id, unsigned long table_size,
+ struct acpi_table_header *table_header,
+ struct acpi_subtable_proc *proc, int proc_num,
+ unsigned int max_entries)
+{
+ struct acpi_subtable_header *entry;
+ unsigned long table_end;
+ int count = 0;
+ int errs = 0;
+ int i;
+
+ if (acpi_disabled)
+ return -ENODEV;
+
+ if (!id)
+ return -EINVAL;
+
+ if (!table_size)
+ return -EINVAL;
+
+ if (!table_header) {
+ pr_warn("%4.4s not present\n", id);
+ return -ENODEV;
+ }
+
+ table_end = (unsigned long)table_header + table_header->length;
+
+ /* Parse all entries looking for a match. */
+
+ entry = (struct acpi_subtable_header *)
+ ((unsigned long)table_header + table_size);
+
+ while (((unsigned long)entry) + sizeof(struct acpi_subtable_header) <
+ table_end) {
+ if (max_entries && count >= max_entries)
+ break;
+
+ for (i = 0; i < proc_num; i++) {
+ if (entry->type != proc[i].id)
+ continue;
+ if (!proc[i].handler ||
+ (!errs && proc[i].handler(entry, table_end))) {
+ errs++;
+ continue;
+ }
+
+ proc[i].count++;
+ break;
+ }
+ if (i != proc_num)
+ count++;
+
+ /*
+ * If entry->length is 0, break from this loop to avoid
+ * infinite loop.
+ */
+ if (entry->length == 0) {
+ pr_err("[%4.4s:0x%02x] Invalid zero length\n", id, proc->id);
+ return -EINVAL;
+ }
+
+ entry = (struct acpi_subtable_header *)
+ ((unsigned long)entry + entry->length);
+ }
+
+ if (max_entries && count > max_entries) {
+ pr_warn("[%4.4s:0x%02x] found the maximum %i entries\n",
+ id, proc->id, count);
+ }
+
+ return errs ? -EINVAL : count;
+}
+
+int __init
+acpi_table_parse_entries_array(char *id,
+ unsigned long table_size,
+ struct acpi_subtable_proc *proc, int proc_num,
+ unsigned int max_entries)
+{
+ struct acpi_table_header *table_header = NULL;
+ int count;
+ u32 instance = 0;
+
+ if (acpi_disabled)
+ return -ENODEV;
+
+ if (!id)
+ return -EINVAL;
+
+ if (!strncmp(id, ACPI_SIG_MADT, 4))
+ instance = acpi_apic_instance;
+
+ acpi_get_table(id, instance, &table_header);
+ if (!table_header) {
+ pr_warn("%4.4s not present\n", id);
+ return -ENODEV;
+ }
+
+ count = acpi_parse_entries_array(id, table_size, table_header,
+ proc, proc_num, max_entries);
+
+ acpi_put_table(table_header);
+ return count;
+}
+
+int __init
+acpi_table_parse_entries(char *id,
+ unsigned long table_size,
+ int entry_id,
+ acpi_tbl_entry_handler handler,
+ unsigned int max_entries)
+{
+ struct acpi_subtable_proc proc = {
+ .id = entry_id,
+ .handler = handler,
+ };
+
+ return acpi_table_parse_entries_array(id, table_size, &proc, 1,
+ max_entries);
+}
+
+int __init
+acpi_table_parse_madt(enum acpi_madt_type id,
+ acpi_tbl_entry_handler handler, unsigned int max_entries)
+{
+ return acpi_table_parse_entries(ACPI_SIG_MADT,
+ sizeof(struct acpi_table_madt), id,
+ handler, max_entries);
+}
+
+/**
+ * acpi_table_parse - find table with @id, run @handler on it
+ * @id: table id to find
+ * @handler: handler to run
+ *
+ * Scan the ACPI System Descriptor Table (STD) for a table matching @id,
+ * run @handler on it.
+ *
+ * Return 0 if table found, -errno if not.
+ */
+int __init acpi_table_parse(char *id, acpi_tbl_table_handler handler)
+{
+ struct acpi_table_header *table = NULL;
+
+ if (acpi_disabled)
+ return -ENODEV;
+
+ if (!id || !handler)
+ return -EINVAL;
+
+ if (strncmp(id, ACPI_SIG_MADT, 4) == 0)
+ acpi_get_table(id, acpi_apic_instance, &table);
+ else
+ acpi_get_table(id, 0, &table);
+
+ if (table) {
+ handler(table);
+ acpi_put_table(table);
+ return 0;
+ } else
+ return -ENODEV;
+}
+
+/*
+ * The BIOS is supposed to supply a single APIC/MADT,
+ * but some report two. Provide a knob to use either.
+ * (don't you wish instance 0 and 1 were not the same?)
+ */
+static void __init check_multiple_madt(void)
+{
+ struct acpi_table_header *table = NULL;
+
+ acpi_get_table(ACPI_SIG_MADT, 2, &table);
+ if (table) {
+ pr_warn("BIOS bug: multiple APIC/MADT found, using %d\n",
+ acpi_apic_instance);
+ pr_warn("If \"acpi_apic_instance=%d\" works better, "
+ "notify linux-acpi@vger.kernel.org\n",
+ acpi_apic_instance ? 0 : 2);
+ acpi_put_table(table);
+
+ } else
+ acpi_apic_instance = 0;
+
+ return;
+}
+
+static void acpi_table_taint(struct acpi_table_header *table)
+{
+ pr_warn("Override [%4.4s-%8.8s], this is unsafe: tainting kernel\n",
+ table->signature, table->oem_table_id);
+ add_taint(TAINT_OVERRIDDEN_ACPI_TABLE, LOCKDEP_NOW_UNRELIABLE);
+}
+
+#ifdef CONFIG_ACPI_TABLE_UPGRADE
+static u64 acpi_tables_addr;
+static int all_tables_size;
+
+/* Copied from acpica/tbutils.c:acpi_tb_checksum() */
+static u8 __init acpi_table_checksum(u8 *buffer, u32 length)
+{
+ u8 sum = 0;
+ u8 *end = buffer + length;
+
+ while (buffer < end)
+ sum = (u8) (sum + *(buffer++));
+ return sum;
+}
+
+/* All but ACPI_SIG_RSDP and ACPI_SIG_FACS: */
+static const char * const table_sigs[] = {
+ ACPI_SIG_BERT, ACPI_SIG_CPEP, ACPI_SIG_ECDT, ACPI_SIG_EINJ,
+ ACPI_SIG_ERST, ACPI_SIG_HEST, ACPI_SIG_MADT, ACPI_SIG_MSCT,
+ ACPI_SIG_SBST, ACPI_SIG_SLIT, ACPI_SIG_SRAT, ACPI_SIG_ASF,
+ ACPI_SIG_BOOT, ACPI_SIG_DBGP, ACPI_SIG_DMAR, ACPI_SIG_HPET,
+ ACPI_SIG_IBFT, ACPI_SIG_IVRS, ACPI_SIG_MCFG, ACPI_SIG_MCHI,
+ ACPI_SIG_SLIC, ACPI_SIG_SPCR, ACPI_SIG_SPMI, ACPI_SIG_TCPA,
+ ACPI_SIG_UEFI, ACPI_SIG_WAET, ACPI_SIG_WDAT, ACPI_SIG_WDDT,
+ ACPI_SIG_WDRT, ACPI_SIG_DSDT, ACPI_SIG_FADT, ACPI_SIG_PSDT,
+ ACPI_SIG_RSDT, ACPI_SIG_XSDT, ACPI_SIG_SSDT, ACPI_SIG_IORT,
+ ACPI_SIG_NFIT, ACPI_SIG_HMAT, ACPI_SIG_PPTT, NULL };
+
+#define ACPI_HEADER_SIZE sizeof(struct acpi_table_header)
+
+#define NR_ACPI_INITRD_TABLES 64
+static struct cpio_data __initdata acpi_initrd_files[NR_ACPI_INITRD_TABLES];
+static DECLARE_BITMAP(acpi_initrd_installed, NR_ACPI_INITRD_TABLES);
+
+#define MAP_CHUNK_SIZE (NR_FIX_BTMAPS << PAGE_SHIFT)
+
+void __init acpi_table_upgrade(void)
+{
+ void *data = (void *)initrd_start;
+ size_t size = initrd_end - initrd_start;
+ int sig, no, table_nr = 0, total_offset = 0;
+ long offset = 0;
+ struct acpi_table_header *table;
+ char cpio_path[32] = "kernel/firmware/acpi/";
+ struct cpio_data file;
+
+ if (data == NULL || size == 0)
+ return;
+
+ for (no = 0; no < NR_ACPI_INITRD_TABLES; no++) {
+ file = find_cpio_data(cpio_path, data, size, &offset);
+ if (!file.data)
+ break;
+
+ data += offset;
+ size -= offset;
+
+ if (file.size < sizeof(struct acpi_table_header)) {
+ pr_err("ACPI OVERRIDE: Table smaller than ACPI header [%s%s]\n",
+ cpio_path, file.name);
+ continue;
+ }
+
+ table = file.data;
+
+ for (sig = 0; table_sigs[sig]; sig++)
+ if (!memcmp(table->signature, table_sigs[sig], 4))
+ break;
+
+ if (!table_sigs[sig]) {
+ pr_err("ACPI OVERRIDE: Unknown signature [%s%s]\n",
+ cpio_path, file.name);
+ continue;
+ }
+ if (file.size != table->length) {
+ pr_err("ACPI OVERRIDE: File length does not match table length [%s%s]\n",
+ cpio_path, file.name);
+ continue;
+ }
+ if (acpi_table_checksum(file.data, table->length)) {
+ pr_err("ACPI OVERRIDE: Bad table checksum [%s%s]\n",
+ cpio_path, file.name);
+ continue;
+ }
+
+ pr_info("%4.4s ACPI table found in initrd [%s%s][0x%x]\n",
+ table->signature, cpio_path, file.name, table->length);
+
+ all_tables_size += table->length;
+ acpi_initrd_files[table_nr].data = file.data;
+ acpi_initrd_files[table_nr].size = file.size;
+ table_nr++;
+ }
+ if (table_nr == 0)
+ return;
+
+ acpi_tables_addr =
+ memblock_find_in_range(0, ACPI_TABLE_UPGRADE_MAX_PHYS,
+ all_tables_size, PAGE_SIZE);
+ if (!acpi_tables_addr) {
+ WARN_ON(1);
+ return;
+ }
+ /*
+ * Only calling e820_add_reserve does not work and the
+ * tables are invalid (memory got used) later.
+ * memblock_reserve works as expected and the tables won't get modified.
+ * But it's not enough on X86 because ioremap will
+ * complain later (used by acpi_os_map_memory) that the pages
+ * that should get mapped are not marked "reserved".
+ * Both memblock_reserve and e820__range_add (via arch_reserve_mem_area)
+ * works fine.
+ */
+ memblock_reserve(acpi_tables_addr, all_tables_size);
+ arch_reserve_mem_area(acpi_tables_addr, all_tables_size);
+
+ /*
+ * early_ioremap only can remap 256k one time. If we map all
+ * tables one time, we will hit the limit. Need to map chunks
+ * one by one during copying the same as that in relocate_initrd().
+ */
+ for (no = 0; no < table_nr; no++) {
+ unsigned char *src_p = acpi_initrd_files[no].data;
+ phys_addr_t size = acpi_initrd_files[no].size;
+ phys_addr_t dest_addr = acpi_tables_addr + total_offset;
+ phys_addr_t slop, clen;
+ char *dest_p;
+
+ total_offset += size;
+
+ while (size) {
+ slop = dest_addr & ~PAGE_MASK;
+ clen = size;
+ if (clen > MAP_CHUNK_SIZE - slop)
+ clen = MAP_CHUNK_SIZE - slop;
+ dest_p = early_memremap(dest_addr & PAGE_MASK,
+ clen + slop);
+ memcpy(dest_p + slop, src_p, clen);
+ early_memunmap(dest_p, clen + slop);
+ src_p += clen;
+ dest_addr += clen;
+ size -= clen;
+ }
+ }
+}
+
+static acpi_status
+acpi_table_initrd_override(struct acpi_table_header *existing_table,
+ acpi_physical_address *address, u32 *length)
+{
+ int table_offset = 0;
+ int table_index = 0;
+ struct acpi_table_header *table;
+ u32 table_length;
+
+ *length = 0;
+ *address = 0;
+ if (!acpi_tables_addr)
+ return AE_OK;
+
+ while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
+ table = acpi_os_map_memory(acpi_tables_addr + table_offset,
+ ACPI_HEADER_SIZE);
+ if (table_offset + table->length > all_tables_size) {
+ acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
+ WARN_ON(1);
+ return AE_OK;
+ }
+
+ table_length = table->length;
+
+ /* Only override tables matched */
+ if (memcmp(existing_table->signature, table->signature, 4) ||
+ memcmp(table->oem_id, existing_table->oem_id,
+ ACPI_OEM_ID_SIZE) ||
+ memcmp(table->oem_table_id, existing_table->oem_table_id,
+ ACPI_OEM_TABLE_ID_SIZE)) {
+ acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
+ goto next_table;
+ }
+ /*
+ * Mark the table to avoid being used in
+ * acpi_table_initrd_scan() and check the revision.
+ */
+ if (test_and_set_bit(table_index, acpi_initrd_installed) ||
+ existing_table->oem_revision >= table->oem_revision) {
+ acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
+ goto next_table;
+ }
+
+ *length = table_length;
+ *address = acpi_tables_addr + table_offset;
+ pr_info("Table Upgrade: override [%4.4s-%6.6s-%8.8s]\n",
+ table->signature, table->oem_id,
+ table->oem_table_id);
+ acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
+ break;
+
+next_table:
+ table_offset += table_length;
+ table_index++;
+ }
+ return AE_OK;
+}
+
+static void __init acpi_table_initrd_scan(void)
+{
+ int table_offset = 0;
+ int table_index = 0;
+ u32 table_length;
+ struct acpi_table_header *table;
+
+ if (!acpi_tables_addr)
+ return;
+
+ while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
+ table = acpi_os_map_memory(acpi_tables_addr + table_offset,
+ ACPI_HEADER_SIZE);
+ if (table_offset + table->length > all_tables_size) {
+ acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
+ WARN_ON(1);
+ return;
+ }
+
+ table_length = table->length;
+
+ /* Skip RSDT/XSDT which should only be used for override */
+ if (ACPI_COMPARE_NAME(table->signature, ACPI_SIG_RSDT) ||
+ ACPI_COMPARE_NAME(table->signature, ACPI_SIG_XSDT)) {
+ acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
+ goto next_table;
+ }
+ /*
+ * Mark the table to avoid being used in
+ * acpi_table_initrd_override(). Though this is not possible
+ * because override is disabled in acpi_install_table().
+ */
+ if (test_and_set_bit(table_index, acpi_initrd_installed)) {
+ acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
+ goto next_table;
+ }
+
+ pr_info("Table Upgrade: install [%4.4s-%6.6s-%8.8s]\n",
+ table->signature, table->oem_id,
+ table->oem_table_id);
+ acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
+ acpi_install_table(acpi_tables_addr + table_offset, TRUE);
+next_table:
+ table_offset += table_length;
+ table_index++;
+ }
+}
+#else
+static acpi_status
+acpi_table_initrd_override(struct acpi_table_header *existing_table,
+ acpi_physical_address *address,
+ u32 *table_length)
+{
+ *table_length = 0;
+ *address = 0;
+ return AE_OK;
+}
+
+static void __init acpi_table_initrd_scan(void)
+{
+}
+#endif /* CONFIG_ACPI_TABLE_UPGRADE */
+
+acpi_status
+acpi_os_physical_table_override(struct acpi_table_header *existing_table,
+ acpi_physical_address *address,
+ u32 *table_length)
+{
+ return acpi_table_initrd_override(existing_table, address,
+ table_length);
+}
+
+acpi_status
+acpi_os_table_override(struct acpi_table_header *existing_table,
+ struct acpi_table_header **new_table)
+{
+ if (!existing_table || !new_table)
+ return AE_BAD_PARAMETER;
+
+ *new_table = NULL;
+
+#ifdef CONFIG_ACPI_CUSTOM_DSDT
+ if (strncmp(existing_table->signature, "DSDT", 4) == 0)
+ *new_table = (struct acpi_table_header *)AmlCode;
+#endif
+ if (*new_table != NULL)
+ acpi_table_taint(existing_table);
+ return AE_OK;
+}
+
+/*
+ * acpi_table_init()
+ *
+ * find RSDP, find and checksum SDT/XSDT.
+ * checksum all tables, print SDT/XSDT
+ *
+ * result: sdt_entry[] is initialized
+ */
+
+int __init acpi_table_init(void)
+{
+ acpi_status status;
+
+ if (acpi_verify_table_checksum) {
+ pr_info("Early table checksum verification enabled\n");
+ acpi_gbl_enable_table_validation = TRUE;
+ } else {
+ pr_info("Early table checksum verification disabled\n");
+ acpi_gbl_enable_table_validation = FALSE;
+ }
+
+ status = acpi_initialize_tables(initial_tables, ACPI_MAX_TABLES, 0);
+ if (ACPI_FAILURE(status))
+ return -EINVAL;
+ acpi_table_initrd_scan();
+
+ check_multiple_madt();
+ return 0;
+}
+
+static int __init acpi_parse_apic_instance(char *str)
+{
+ if (!str)
+ return -EINVAL;
+
+ if (kstrtoint(str, 0, &acpi_apic_instance))
+ return -EINVAL;
+
+ pr_notice("Shall use APIC/MADT table %d\n", acpi_apic_instance);
+
+ return 0;
+}
+
+early_param("acpi_apic_instance", acpi_parse_apic_instance);
+
+static int __init acpi_force_table_verification_setup(char *s)
+{
+ acpi_verify_table_checksum = true;
+
+ return 0;
+}
+
+early_param("acpi_force_table_verification", acpi_force_table_verification_setup);
+
+static int __init acpi_force_32bit_fadt_addr(char *s)
+{
+ pr_info("Forcing 32 Bit FADT addresses\n");
+ acpi_gbl_use32_bit_fadt_addresses = TRUE;
+
+ return 0;
+}
+
+early_param("acpi_force_32bit_fadt_addr", acpi_force_32bit_fadt_addr);