summaryrefslogtreecommitdiffstats
path: root/arch/x86/kernel/mpparse.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--arch/x86/kernel/mpparse.c944
1 files changed, 944 insertions, 0 deletions
diff --git a/arch/x86/kernel/mpparse.c b/arch/x86/kernel/mpparse.c
new file mode 100644
index 000000000..8f06449aa
--- /dev/null
+++ b/arch/x86/kernel/mpparse.c
@@ -0,0 +1,944 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Intel Multiprocessor Specification 1.1 and 1.4
+ * compliant MP-table parsing routines.
+ *
+ * (c) 1995 Alan Cox, Building #3 <alan@lxorguk.ukuu.org.uk>
+ * (c) 1998, 1999, 2000, 2009 Ingo Molnar <mingo@redhat.com>
+ * (c) 2008 Alexey Starikovskiy <astarikovskiy@suse.de>
+ */
+
+#include <linux/mm.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/memblock.h>
+#include <linux/kernel_stat.h>
+#include <linux/mc146818rtc.h>
+#include <linux/bitops.h>
+#include <linux/acpi.h>
+#include <linux/smp.h>
+#include <linux/pci.h>
+
+#include <asm/io_apic.h>
+#include <asm/acpi.h>
+#include <asm/irqdomain.h>
+#include <asm/mtrr.h>
+#include <asm/mpspec.h>
+#include <asm/proto.h>
+#include <asm/bios_ebda.h>
+#include <asm/e820/api.h>
+#include <asm/setup.h>
+#include <asm/smp.h>
+
+#include <asm/apic.h>
+/*
+ * Checksum an MP configuration block.
+ */
+
+static int __init mpf_checksum(unsigned char *mp, int len)
+{
+ int sum = 0;
+
+ while (len--)
+ sum += *mp++;
+
+ return sum & 0xFF;
+}
+
+static void __init MP_processor_info(struct mpc_cpu *m)
+{
+ int apicid;
+ char *bootup_cpu = "";
+
+ if (!(m->cpuflag & CPU_ENABLED)) {
+ disabled_cpus++;
+ return;
+ }
+
+ apicid = m->apicid;
+
+ if (m->cpuflag & CPU_BOOTPROCESSOR) {
+ bootup_cpu = " (Bootup-CPU)";
+ boot_cpu_physical_apicid = m->apicid;
+ }
+
+ pr_info("Processor #%d%s\n", m->apicid, bootup_cpu);
+ generic_processor_info(apicid, m->apicver);
+}
+
+#ifdef CONFIG_X86_IO_APIC
+static void __init mpc_oem_bus_info(struct mpc_bus *m, char *str)
+{
+ memcpy(str, m->bustype, 6);
+ str[6] = 0;
+ apic_printk(APIC_VERBOSE, "Bus #%d is %s\n", m->busid, str);
+}
+
+static void __init MP_bus_info(struct mpc_bus *m)
+{
+ char str[7];
+
+ mpc_oem_bus_info(m, str);
+
+#if MAX_MP_BUSSES < 256
+ if (m->busid >= MAX_MP_BUSSES) {
+ pr_warn("MP table busid value (%d) for bustype %s is too large, max. supported is %d\n",
+ m->busid, str, MAX_MP_BUSSES - 1);
+ return;
+ }
+#endif
+
+ set_bit(m->busid, mp_bus_not_pci);
+ if (strncmp(str, BUSTYPE_ISA, sizeof(BUSTYPE_ISA) - 1) == 0) {
+#ifdef CONFIG_EISA
+ mp_bus_id_to_type[m->busid] = MP_BUS_ISA;
+#endif
+ } else if (strncmp(str, BUSTYPE_PCI, sizeof(BUSTYPE_PCI) - 1) == 0) {
+ clear_bit(m->busid, mp_bus_not_pci);
+#ifdef CONFIG_EISA
+ mp_bus_id_to_type[m->busid] = MP_BUS_PCI;
+ } else if (strncmp(str, BUSTYPE_EISA, sizeof(BUSTYPE_EISA) - 1) == 0) {
+ mp_bus_id_to_type[m->busid] = MP_BUS_EISA;
+#endif
+ } else
+ pr_warn("Unknown bustype %s - ignoring\n", str);
+}
+
+static void __init MP_ioapic_info(struct mpc_ioapic *m)
+{
+ struct ioapic_domain_cfg cfg = {
+ .type = IOAPIC_DOMAIN_LEGACY,
+ .ops = &mp_ioapic_irqdomain_ops,
+ };
+
+ if (m->flags & MPC_APIC_USABLE)
+ mp_register_ioapic(m->apicid, m->apicaddr, gsi_top, &cfg);
+}
+
+static void __init print_mp_irq_info(struct mpc_intsrc *mp_irq)
+{
+ apic_printk(APIC_VERBOSE,
+ "Int: type %d, pol %d, trig %d, bus %02x, IRQ %02x, APIC ID %x, APIC INT %02x\n",
+ mp_irq->irqtype, mp_irq->irqflag & 3,
+ (mp_irq->irqflag >> 2) & 3, mp_irq->srcbus,
+ mp_irq->srcbusirq, mp_irq->dstapic, mp_irq->dstirq);
+}
+
+#else /* CONFIG_X86_IO_APIC */
+static inline void __init MP_bus_info(struct mpc_bus *m) {}
+static inline void __init MP_ioapic_info(struct mpc_ioapic *m) {}
+#endif /* CONFIG_X86_IO_APIC */
+
+static void __init MP_lintsrc_info(struct mpc_lintsrc *m)
+{
+ apic_printk(APIC_VERBOSE,
+ "Lint: type %d, pol %d, trig %d, bus %02x, IRQ %02x, APIC ID %x, APIC LINT %02x\n",
+ m->irqtype, m->irqflag & 3, (m->irqflag >> 2) & 3, m->srcbusid,
+ m->srcbusirq, m->destapic, m->destapiclint);
+}
+
+/*
+ * Read/parse the MPC
+ */
+static int __init smp_check_mpc(struct mpc_table *mpc, char *oem, char *str)
+{
+
+ if (memcmp(mpc->signature, MPC_SIGNATURE, 4)) {
+ pr_err("MPTABLE: bad signature [%c%c%c%c]!\n",
+ mpc->signature[0], mpc->signature[1],
+ mpc->signature[2], mpc->signature[3]);
+ return 0;
+ }
+ if (mpf_checksum((unsigned char *)mpc, mpc->length)) {
+ pr_err("MPTABLE: checksum error!\n");
+ return 0;
+ }
+ if (mpc->spec != 0x01 && mpc->spec != 0x04) {
+ pr_err("MPTABLE: bad table version (%d)!!\n", mpc->spec);
+ return 0;
+ }
+ if (!mpc->lapic) {
+ pr_err("MPTABLE: null local APIC address!\n");
+ return 0;
+ }
+ memcpy(oem, mpc->oem, 8);
+ oem[8] = 0;
+ pr_info("MPTABLE: OEM ID: %s\n", oem);
+
+ memcpy(str, mpc->productid, 12);
+ str[12] = 0;
+
+ pr_info("MPTABLE: Product ID: %s\n", str);
+
+ pr_info("MPTABLE: APIC at: 0x%X\n", mpc->lapic);
+
+ return 1;
+}
+
+static void skip_entry(unsigned char **ptr, int *count, int size)
+{
+ *ptr += size;
+ *count += size;
+}
+
+static void __init smp_dump_mptable(struct mpc_table *mpc, unsigned char *mpt)
+{
+ pr_err("Your mptable is wrong, contact your HW vendor!\n");
+ pr_cont("type %x\n", *mpt);
+ print_hex_dump(KERN_ERR, " ", DUMP_PREFIX_ADDRESS, 16,
+ 1, mpc, mpc->length, 1);
+}
+
+static int __init smp_read_mpc(struct mpc_table *mpc, unsigned early)
+{
+ char str[16];
+ char oem[10];
+
+ int count = sizeof(*mpc);
+ unsigned char *mpt = ((unsigned char *)mpc) + count;
+
+ if (!smp_check_mpc(mpc, oem, str))
+ return 0;
+
+ /* Initialize the lapic mapping */
+ if (!acpi_lapic)
+ register_lapic_address(mpc->lapic);
+
+ if (early)
+ return 1;
+
+ /* Now process the configuration blocks. */
+ while (count < mpc->length) {
+ switch (*mpt) {
+ case MP_PROCESSOR:
+ /* ACPI may have already provided this data */
+ if (!acpi_lapic)
+ MP_processor_info((struct mpc_cpu *)mpt);
+ skip_entry(&mpt, &count, sizeof(struct mpc_cpu));
+ break;
+ case MP_BUS:
+ MP_bus_info((struct mpc_bus *)mpt);
+ skip_entry(&mpt, &count, sizeof(struct mpc_bus));
+ break;
+ case MP_IOAPIC:
+ MP_ioapic_info((struct mpc_ioapic *)mpt);
+ skip_entry(&mpt, &count, sizeof(struct mpc_ioapic));
+ break;
+ case MP_INTSRC:
+ mp_save_irq((struct mpc_intsrc *)mpt);
+ skip_entry(&mpt, &count, sizeof(struct mpc_intsrc));
+ break;
+ case MP_LINTSRC:
+ MP_lintsrc_info((struct mpc_lintsrc *)mpt);
+ skip_entry(&mpt, &count, sizeof(struct mpc_lintsrc));
+ break;
+ default:
+ /* wrong mptable */
+ smp_dump_mptable(mpc, mpt);
+ count = mpc->length;
+ break;
+ }
+ }
+
+ if (!num_processors)
+ pr_err("MPTABLE: no processors registered!\n");
+ return num_processors;
+}
+
+#ifdef CONFIG_X86_IO_APIC
+
+static int __init ELCR_trigger(unsigned int irq)
+{
+ unsigned int port;
+
+ port = 0x4d0 + (irq >> 3);
+ return (inb(port) >> (irq & 7)) & 1;
+}
+
+static void __init construct_default_ioirq_mptable(int mpc_default_type)
+{
+ struct mpc_intsrc intsrc;
+ int i;
+ int ELCR_fallback = 0;
+
+ intsrc.type = MP_INTSRC;
+ intsrc.irqflag = MP_IRQTRIG_DEFAULT | MP_IRQPOL_DEFAULT;
+ intsrc.srcbus = 0;
+ intsrc.dstapic = mpc_ioapic_id(0);
+
+ intsrc.irqtype = mp_INT;
+
+ /*
+ * If true, we have an ISA/PCI system with no IRQ entries
+ * in the MP table. To prevent the PCI interrupts from being set up
+ * incorrectly, we try to use the ELCR. The sanity check to see if
+ * there is good ELCR data is very simple - IRQ0, 1, 2 and 13 can
+ * never be level sensitive, so we simply see if the ELCR agrees.
+ * If it does, we assume it's valid.
+ */
+ if (mpc_default_type == 5) {
+ pr_info("ISA/PCI bus type with no IRQ information... falling back to ELCR\n");
+
+ if (ELCR_trigger(0) || ELCR_trigger(1) || ELCR_trigger(2) ||
+ ELCR_trigger(13))
+ pr_err("ELCR contains invalid data... not using ELCR\n");
+ else {
+ pr_info("Using ELCR to identify PCI interrupts\n");
+ ELCR_fallback = 1;
+ }
+ }
+
+ for (i = 0; i < 16; i++) {
+ switch (mpc_default_type) {
+ case 2:
+ if (i == 0 || i == 13)
+ continue; /* IRQ0 & IRQ13 not connected */
+ fallthrough;
+ default:
+ if (i == 2)
+ continue; /* IRQ2 is never connected */
+ }
+
+ if (ELCR_fallback) {
+ /*
+ * If the ELCR indicates a level-sensitive interrupt, we
+ * copy that information over to the MP table in the
+ * irqflag field (level sensitive, active high polarity).
+ */
+ if (ELCR_trigger(i)) {
+ intsrc.irqflag = MP_IRQTRIG_LEVEL |
+ MP_IRQPOL_ACTIVE_HIGH;
+ } else {
+ intsrc.irqflag = MP_IRQTRIG_DEFAULT |
+ MP_IRQPOL_DEFAULT;
+ }
+ }
+
+ intsrc.srcbusirq = i;
+ intsrc.dstirq = i ? i : 2; /* IRQ0 to INTIN2 */
+ mp_save_irq(&intsrc);
+ }
+
+ intsrc.irqtype = mp_ExtINT;
+ intsrc.srcbusirq = 0;
+ intsrc.dstirq = 0; /* 8259A to INTIN0 */
+ mp_save_irq(&intsrc);
+}
+
+
+static void __init construct_ioapic_table(int mpc_default_type)
+{
+ struct mpc_ioapic ioapic;
+ struct mpc_bus bus;
+
+ bus.type = MP_BUS;
+ bus.busid = 0;
+ switch (mpc_default_type) {
+ default:
+ pr_err("???\nUnknown standard configuration %d\n",
+ mpc_default_type);
+ fallthrough;
+ case 1:
+ case 5:
+ memcpy(bus.bustype, "ISA ", 6);
+ break;
+ case 2:
+ case 6:
+ case 3:
+ memcpy(bus.bustype, "EISA ", 6);
+ break;
+ }
+ MP_bus_info(&bus);
+ if (mpc_default_type > 4) {
+ bus.busid = 1;
+ memcpy(bus.bustype, "PCI ", 6);
+ MP_bus_info(&bus);
+ }
+
+ ioapic.type = MP_IOAPIC;
+ ioapic.apicid = 2;
+ ioapic.apicver = mpc_default_type > 4 ? 0x10 : 0x01;
+ ioapic.flags = MPC_APIC_USABLE;
+ ioapic.apicaddr = IO_APIC_DEFAULT_PHYS_BASE;
+ MP_ioapic_info(&ioapic);
+
+ /*
+ * We set up most of the low 16 IO-APIC pins according to MPS rules.
+ */
+ construct_default_ioirq_mptable(mpc_default_type);
+}
+#else
+static inline void __init construct_ioapic_table(int mpc_default_type) { }
+#endif
+
+static inline void __init construct_default_ISA_mptable(int mpc_default_type)
+{
+ struct mpc_cpu processor;
+ struct mpc_lintsrc lintsrc;
+ int linttypes[2] = { mp_ExtINT, mp_NMI };
+ int i;
+
+ /*
+ * local APIC has default address
+ */
+ mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
+
+ /*
+ * 2 CPUs, numbered 0 & 1.
+ */
+ processor.type = MP_PROCESSOR;
+ /* Either an integrated APIC or a discrete 82489DX. */
+ processor.apicver = mpc_default_type > 4 ? 0x10 : 0x01;
+ processor.cpuflag = CPU_ENABLED;
+ processor.cpufeature = (boot_cpu_data.x86 << 8) |
+ (boot_cpu_data.x86_model << 4) | boot_cpu_data.x86_stepping;
+ processor.featureflag = boot_cpu_data.x86_capability[CPUID_1_EDX];
+ processor.reserved[0] = 0;
+ processor.reserved[1] = 0;
+ for (i = 0; i < 2; i++) {
+ processor.apicid = i;
+ MP_processor_info(&processor);
+ }
+
+ construct_ioapic_table(mpc_default_type);
+
+ lintsrc.type = MP_LINTSRC;
+ lintsrc.irqflag = MP_IRQTRIG_DEFAULT | MP_IRQPOL_DEFAULT;
+ lintsrc.srcbusid = 0;
+ lintsrc.srcbusirq = 0;
+ lintsrc.destapic = MP_APIC_ALL;
+ for (i = 0; i < 2; i++) {
+ lintsrc.irqtype = linttypes[i];
+ lintsrc.destapiclint = i;
+ MP_lintsrc_info(&lintsrc);
+ }
+}
+
+static unsigned long mpf_base;
+static bool mpf_found;
+
+static unsigned long __init get_mpc_size(unsigned long physptr)
+{
+ struct mpc_table *mpc;
+ unsigned long size;
+
+ mpc = early_memremap(physptr, PAGE_SIZE);
+ size = mpc->length;
+ early_memunmap(mpc, PAGE_SIZE);
+ apic_printk(APIC_VERBOSE, " mpc: %lx-%lx\n", physptr, physptr + size);
+
+ return size;
+}
+
+static int __init check_physptr(struct mpf_intel *mpf, unsigned int early)
+{
+ struct mpc_table *mpc;
+ unsigned long size;
+
+ size = get_mpc_size(mpf->physptr);
+ mpc = early_memremap(mpf->physptr, size);
+
+ /*
+ * Read the physical hardware table. Anything here will
+ * override the defaults.
+ */
+ if (!smp_read_mpc(mpc, early)) {
+#ifdef CONFIG_X86_LOCAL_APIC
+ smp_found_config = 0;
+#endif
+ pr_err("BIOS bug, MP table errors detected!...\n");
+ pr_cont("... disabling SMP support. (tell your hw vendor)\n");
+ early_memunmap(mpc, size);
+ return -1;
+ }
+ early_memunmap(mpc, size);
+
+ if (early)
+ return -1;
+
+#ifdef CONFIG_X86_IO_APIC
+ /*
+ * If there are no explicit MP IRQ entries, then we are
+ * broken. We set up most of the low 16 IO-APIC pins to
+ * ISA defaults and hope it will work.
+ */
+ if (!mp_irq_entries) {
+ struct mpc_bus bus;
+
+ pr_err("BIOS bug, no explicit IRQ entries, using default mptable. (tell your hw vendor)\n");
+
+ bus.type = MP_BUS;
+ bus.busid = 0;
+ memcpy(bus.bustype, "ISA ", 6);
+ MP_bus_info(&bus);
+
+ construct_default_ioirq_mptable(0);
+ }
+#endif
+
+ return 0;
+}
+
+/*
+ * Scan the memory blocks for an SMP configuration block.
+ */
+void __init default_get_smp_config(unsigned int early)
+{
+ struct mpf_intel *mpf;
+
+ if (!smp_found_config)
+ return;
+
+ if (!mpf_found)
+ return;
+
+ if (acpi_lapic && early)
+ return;
+
+ /*
+ * MPS doesn't support hyperthreading, aka only have
+ * thread 0 apic id in MPS table
+ */
+ if (acpi_lapic && acpi_ioapic)
+ return;
+
+ mpf = early_memremap(mpf_base, sizeof(*mpf));
+ if (!mpf) {
+ pr_err("MPTABLE: error mapping MP table\n");
+ return;
+ }
+
+ pr_info("Intel MultiProcessor Specification v1.%d\n",
+ mpf->specification);
+#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86_32)
+ if (mpf->feature2 & (1 << 7)) {
+ pr_info(" IMCR and PIC compatibility mode.\n");
+ pic_mode = 1;
+ } else {
+ pr_info(" Virtual Wire compatibility mode.\n");
+ pic_mode = 0;
+ }
+#endif
+ /*
+ * Now see if we need to read further.
+ */
+ if (mpf->feature1) {
+ if (early) {
+ /*
+ * local APIC has default address
+ */
+ mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
+ goto out;
+ }
+
+ pr_info("Default MP configuration #%d\n", mpf->feature1);
+ construct_default_ISA_mptable(mpf->feature1);
+
+ } else if (mpf->physptr) {
+ if (check_physptr(mpf, early))
+ goto out;
+ } else
+ BUG();
+
+ if (!early)
+ pr_info("Processors: %d\n", num_processors);
+ /*
+ * Only use the first configuration found.
+ */
+out:
+ early_memunmap(mpf, sizeof(*mpf));
+}
+
+static void __init smp_reserve_memory(struct mpf_intel *mpf)
+{
+ memblock_reserve(mpf->physptr, get_mpc_size(mpf->physptr));
+}
+
+static int __init smp_scan_config(unsigned long base, unsigned long length)
+{
+ unsigned int *bp;
+ struct mpf_intel *mpf;
+ int ret = 0;
+
+ apic_printk(APIC_VERBOSE, "Scan for SMP in [mem %#010lx-%#010lx]\n",
+ base, base + length - 1);
+ BUILD_BUG_ON(sizeof(*mpf) != 16);
+
+ while (length > 0) {
+ bp = early_memremap(base, length);
+ mpf = (struct mpf_intel *)bp;
+ if ((*bp == SMP_MAGIC_IDENT) &&
+ (mpf->length == 1) &&
+ !mpf_checksum((unsigned char *)bp, 16) &&
+ ((mpf->specification == 1)
+ || (mpf->specification == 4))) {
+#ifdef CONFIG_X86_LOCAL_APIC
+ smp_found_config = 1;
+#endif
+ mpf_base = base;
+ mpf_found = true;
+
+ pr_info("found SMP MP-table at [mem %#010lx-%#010lx]\n",
+ base, base + sizeof(*mpf) - 1);
+
+ memblock_reserve(base, sizeof(*mpf));
+ if (mpf->physptr)
+ smp_reserve_memory(mpf);
+
+ ret = 1;
+ }
+ early_memunmap(bp, length);
+
+ if (ret)
+ break;
+
+ base += 16;
+ length -= 16;
+ }
+ return ret;
+}
+
+void __init default_find_smp_config(void)
+{
+ unsigned int address;
+
+ /*
+ * FIXME: Linux assumes you have 640K of base ram..
+ * this continues the error...
+ *
+ * 1) Scan the bottom 1K for a signature
+ * 2) Scan the top 1K of base RAM
+ * 3) Scan the 64K of bios
+ */
+ if (smp_scan_config(0x0, 0x400) ||
+ smp_scan_config(639 * 0x400, 0x400) ||
+ smp_scan_config(0xF0000, 0x10000))
+ return;
+ /*
+ * If it is an SMP machine we should know now, unless the
+ * configuration is in an EISA bus machine with an
+ * extended bios data area.
+ *
+ * there is a real-mode segmented pointer pointing to the
+ * 4K EBDA area at 0x40E, calculate and scan it here.
+ *
+ * NOTE! There are Linux loaders that will corrupt the EBDA
+ * area, and as such this kind of SMP config may be less
+ * trustworthy, simply because the SMP table may have been
+ * stomped on during early boot. These loaders are buggy and
+ * should be fixed.
+ *
+ * MP1.4 SPEC states to only scan first 1K of 4K EBDA.
+ */
+
+ address = get_bios_ebda();
+ if (address)
+ smp_scan_config(address, 0x400);
+}
+
+#ifdef CONFIG_X86_IO_APIC
+static u8 __initdata irq_used[MAX_IRQ_SOURCES];
+
+static int __init get_MP_intsrc_index(struct mpc_intsrc *m)
+{
+ int i;
+
+ if (m->irqtype != mp_INT)
+ return 0;
+
+ if (m->irqflag != (MP_IRQTRIG_LEVEL | MP_IRQPOL_ACTIVE_LOW))
+ return 0;
+
+ /* not legacy */
+
+ for (i = 0; i < mp_irq_entries; i++) {
+ if (mp_irqs[i].irqtype != mp_INT)
+ continue;
+
+ if (mp_irqs[i].irqflag != (MP_IRQTRIG_LEVEL |
+ MP_IRQPOL_ACTIVE_LOW))
+ continue;
+
+ if (mp_irqs[i].srcbus != m->srcbus)
+ continue;
+ if (mp_irqs[i].srcbusirq != m->srcbusirq)
+ continue;
+ if (irq_used[i]) {
+ /* already claimed */
+ return -2;
+ }
+ irq_used[i] = 1;
+ return i;
+ }
+
+ /* not found */
+ return -1;
+}
+
+#define SPARE_SLOT_NUM 20
+
+static struct mpc_intsrc __initdata *m_spare[SPARE_SLOT_NUM];
+
+static void __init check_irq_src(struct mpc_intsrc *m, int *nr_m_spare)
+{
+ int i;
+
+ apic_printk(APIC_VERBOSE, "OLD ");
+ print_mp_irq_info(m);
+
+ i = get_MP_intsrc_index(m);
+ if (i > 0) {
+ memcpy(m, &mp_irqs[i], sizeof(*m));
+ apic_printk(APIC_VERBOSE, "NEW ");
+ print_mp_irq_info(&mp_irqs[i]);
+ return;
+ }
+ if (!i) {
+ /* legacy, do nothing */
+ return;
+ }
+ if (*nr_m_spare < SPARE_SLOT_NUM) {
+ /*
+ * not found (-1), or duplicated (-2) are invalid entries,
+ * we need to use the slot later
+ */
+ m_spare[*nr_m_spare] = m;
+ *nr_m_spare += 1;
+ }
+}
+
+static int __init
+check_slot(unsigned long mpc_new_phys, unsigned long mpc_new_length, int count)
+{
+ if (!mpc_new_phys || count <= mpc_new_length) {
+ WARN(1, "update_mptable: No spare slots (length: %x)\n", count);
+ return -1;
+ }
+
+ return 0;
+}
+#else /* CONFIG_X86_IO_APIC */
+static
+inline void __init check_irq_src(struct mpc_intsrc *m, int *nr_m_spare) {}
+#endif /* CONFIG_X86_IO_APIC */
+
+static int __init replace_intsrc_all(struct mpc_table *mpc,
+ unsigned long mpc_new_phys,
+ unsigned long mpc_new_length)
+{
+#ifdef CONFIG_X86_IO_APIC
+ int i;
+#endif
+ int count = sizeof(*mpc);
+ int nr_m_spare = 0;
+ unsigned char *mpt = ((unsigned char *)mpc) + count;
+
+ pr_info("mpc_length %x\n", mpc->length);
+ while (count < mpc->length) {
+ switch (*mpt) {
+ case MP_PROCESSOR:
+ skip_entry(&mpt, &count, sizeof(struct mpc_cpu));
+ break;
+ case MP_BUS:
+ skip_entry(&mpt, &count, sizeof(struct mpc_bus));
+ break;
+ case MP_IOAPIC:
+ skip_entry(&mpt, &count, sizeof(struct mpc_ioapic));
+ break;
+ case MP_INTSRC:
+ check_irq_src((struct mpc_intsrc *)mpt, &nr_m_spare);
+ skip_entry(&mpt, &count, sizeof(struct mpc_intsrc));
+ break;
+ case MP_LINTSRC:
+ skip_entry(&mpt, &count, sizeof(struct mpc_lintsrc));
+ break;
+ default:
+ /* wrong mptable */
+ smp_dump_mptable(mpc, mpt);
+ goto out;
+ }
+ }
+
+#ifdef CONFIG_X86_IO_APIC
+ for (i = 0; i < mp_irq_entries; i++) {
+ if (irq_used[i])
+ continue;
+
+ if (mp_irqs[i].irqtype != mp_INT)
+ continue;
+
+ if (mp_irqs[i].irqflag != (MP_IRQTRIG_LEVEL |
+ MP_IRQPOL_ACTIVE_LOW))
+ continue;
+
+ if (nr_m_spare > 0) {
+ apic_printk(APIC_VERBOSE, "*NEW* found\n");
+ nr_m_spare--;
+ memcpy(m_spare[nr_m_spare], &mp_irqs[i], sizeof(mp_irqs[i]));
+ m_spare[nr_m_spare] = NULL;
+ } else {
+ struct mpc_intsrc *m = (struct mpc_intsrc *)mpt;
+ count += sizeof(struct mpc_intsrc);
+ if (check_slot(mpc_new_phys, mpc_new_length, count) < 0)
+ goto out;
+ memcpy(m, &mp_irqs[i], sizeof(*m));
+ mpc->length = count;
+ mpt += sizeof(struct mpc_intsrc);
+ }
+ print_mp_irq_info(&mp_irqs[i]);
+ }
+#endif
+out:
+ /* update checksum */
+ mpc->checksum = 0;
+ mpc->checksum -= mpf_checksum((unsigned char *)mpc, mpc->length);
+
+ return 0;
+}
+
+int enable_update_mptable;
+
+static int __init update_mptable_setup(char *str)
+{
+ enable_update_mptable = 1;
+#ifdef CONFIG_PCI
+ pci_routeirq = 1;
+#endif
+ return 0;
+}
+early_param("update_mptable", update_mptable_setup);
+
+static unsigned long __initdata mpc_new_phys;
+static unsigned long mpc_new_length __initdata = 4096;
+
+/* alloc_mptable or alloc_mptable=4k */
+static int __initdata alloc_mptable;
+static int __init parse_alloc_mptable_opt(char *p)
+{
+ enable_update_mptable = 1;
+#ifdef CONFIG_PCI
+ pci_routeirq = 1;
+#endif
+ alloc_mptable = 1;
+ if (!p)
+ return 0;
+ mpc_new_length = memparse(p, &p);
+ return 0;
+}
+early_param("alloc_mptable", parse_alloc_mptable_opt);
+
+void __init e820__memblock_alloc_reserved_mpc_new(void)
+{
+ if (enable_update_mptable && alloc_mptable)
+ mpc_new_phys = e820__memblock_alloc_reserved(mpc_new_length, 4);
+}
+
+static int __init update_mp_table(void)
+{
+ char str[16];
+ char oem[10];
+ struct mpf_intel *mpf;
+ struct mpc_table *mpc, *mpc_new;
+ unsigned long size;
+
+ if (!enable_update_mptable)
+ return 0;
+
+ if (!mpf_found)
+ return 0;
+
+ mpf = early_memremap(mpf_base, sizeof(*mpf));
+ if (!mpf) {
+ pr_err("MPTABLE: mpf early_memremap() failed\n");
+ return 0;
+ }
+
+ /*
+ * Now see if we need to go further.
+ */
+ if (mpf->feature1)
+ goto do_unmap_mpf;
+
+ if (!mpf->physptr)
+ goto do_unmap_mpf;
+
+ size = get_mpc_size(mpf->physptr);
+ mpc = early_memremap(mpf->physptr, size);
+ if (!mpc) {
+ pr_err("MPTABLE: mpc early_memremap() failed\n");
+ goto do_unmap_mpf;
+ }
+
+ if (!smp_check_mpc(mpc, oem, str))
+ goto do_unmap_mpc;
+
+ pr_info("mpf: %llx\n", (u64)mpf_base);
+ pr_info("physptr: %x\n", mpf->physptr);
+
+ if (mpc_new_phys && mpc->length > mpc_new_length) {
+ mpc_new_phys = 0;
+ pr_info("mpc_new_length is %ld, please use alloc_mptable=8k\n",
+ mpc_new_length);
+ }
+
+ if (!mpc_new_phys) {
+ unsigned char old, new;
+ /* check if we can change the position */
+ mpc->checksum = 0;
+ old = mpf_checksum((unsigned char *)mpc, mpc->length);
+ mpc->checksum = 0xff;
+ new = mpf_checksum((unsigned char *)mpc, mpc->length);
+ if (old == new) {
+ pr_info("mpc is readonly, please try alloc_mptable instead\n");
+ goto do_unmap_mpc;
+ }
+ pr_info("use in-position replacing\n");
+ } else {
+ mpc_new = early_memremap(mpc_new_phys, mpc_new_length);
+ if (!mpc_new) {
+ pr_err("MPTABLE: new mpc early_memremap() failed\n");
+ goto do_unmap_mpc;
+ }
+ mpf->physptr = mpc_new_phys;
+ memcpy(mpc_new, mpc, mpc->length);
+ early_memunmap(mpc, size);
+ mpc = mpc_new;
+ size = mpc_new_length;
+ /* check if we can modify that */
+ if (mpc_new_phys - mpf->physptr) {
+ struct mpf_intel *mpf_new;
+ /* steal 16 bytes from [0, 1k) */
+ mpf_new = early_memremap(0x400 - 16, sizeof(*mpf_new));
+ if (!mpf_new) {
+ pr_err("MPTABLE: new mpf early_memremap() failed\n");
+ goto do_unmap_mpc;
+ }
+ pr_info("mpf new: %x\n", 0x400 - 16);
+ memcpy(mpf_new, mpf, 16);
+ early_memunmap(mpf, sizeof(*mpf));
+ mpf = mpf_new;
+ mpf->physptr = mpc_new_phys;
+ }
+ mpf->checksum = 0;
+ mpf->checksum -= mpf_checksum((unsigned char *)mpf, 16);
+ pr_info("physptr new: %x\n", mpf->physptr);
+ }
+
+ /*
+ * only replace the one with mp_INT and
+ * MP_IRQ_TRIGGER_LEVEL|MP_IRQ_POLARITY_LOW,
+ * already in mp_irqs , stored by ... and mp_config_acpi_gsi,
+ * may need pci=routeirq for all coverage
+ */
+ replace_intsrc_all(mpc, mpc_new_phys, mpc_new_length);
+
+do_unmap_mpc:
+ early_memunmap(mpc, size);
+
+do_unmap_mpf:
+ early_memunmap(mpf, sizeof(*mpf));
+
+ return 0;
+}
+
+late_initcall(update_mp_table);