diff options
Diffstat (limited to 'hw/i386/pc.c')
| -rw-r--r-- | hw/i386/pc.c | 82 |
1 files changed, 51 insertions, 31 deletions
diff --git a/hw/i386/pc.c b/hw/i386/pc.c index fb8f29c34c..f56ea0f87b 100644 --- a/hw/i386/pc.c +++ b/hw/i386/pc.c @@ -68,6 +68,7 @@ #include "qapi-visit.h" #include "qom/cpu.h" #include "hw/nmi.h" +#include "hw/i386/intel_iommu.h" /* debug PC/ISA interrupts */ //#define DEBUG_IRQ @@ -746,17 +747,15 @@ static FWCfgState *bochs_bios_init(AddressSpace *as, PCMachineState *pcms) /* FW_CFG_MAX_CPUS is a bit confusing/problematic on x86: * - * SeaBIOS needs FW_CFG_MAX_CPUS for CPU hotplug, but the CPU hotplug - * QEMU<->SeaBIOS interface is not based on the "CPU index", but on the APIC - * ID of hotplugged CPUs[1]. This means that FW_CFG_MAX_CPUS is not the - * "maximum number of CPUs", but the "limit to the APIC ID values SeaBIOS - * may see". + * For machine types prior to 1.8, SeaBIOS needs FW_CFG_MAX_CPUS for + * building MPTable, ACPI MADT, ACPI CPU hotplug and ACPI SRAT table, + * that tables are based on xAPIC ID and QEMU<->SeaBIOS interface + * for CPU hotplug also uses APIC ID and not "CPU index". + * This means that FW_CFG_MAX_CPUS is not the "maximum number of CPUs", + * but the "limit to the APIC ID values SeaBIOS may see". * - * So, this means we must not use max_cpus, here, but the maximum possible - * APIC ID value, plus one. - * - * [1] The only kind of "CPU identifier" used between SeaBIOS and QEMU is - * the APIC ID, not the "CPU index" + * So for compatibility reasons with old BIOSes we are stuck with + * "etc/max-cpus" actually being apic_id_limit */ fw_cfg_add_i16(fw_cfg, FW_CFG_MAX_CPUS, (uint16_t)pcms->apic_id_limit); fw_cfg_add_i64(fw_cfg, FW_CFG_RAM_SIZE, (uint64_t)ram_size); @@ -1087,17 +1086,6 @@ void pc_acpi_smi_interrupt(void *opaque, int irq, int level) } } -static int pc_present_cpus_count(PCMachineState *pcms) -{ - int i, boot_cpus = 0; - for (i = 0; i < pcms->possible_cpus->len; i++) { - if (pcms->possible_cpus->cpus[i].cpu) { - boot_cpus++; - } - } - return boot_cpus; -} - static X86CPU *pc_new_cpu(const char *typename, int64_t apic_id, Error **errp) { @@ -1190,12 +1178,6 @@ void pc_cpus_init(PCMachineState *pcms) * This is used for FW_CFG_MAX_CPUS. See comments on bochs_bios_init(). */ pcms->apic_id_limit = x86_cpu_apic_id_from_index(max_cpus - 1) + 1; - if (pcms->apic_id_limit > ACPI_CPU_HOTPLUG_ID_LIMIT) { - error_report("max_cpus is too large. APIC ID of last CPU is %u", - pcms->apic_id_limit - 1); - exit(1); - } - pcms->possible_cpus = g_malloc0(sizeof(CPUArchIdList) + sizeof(CPUArchId) * max_cpus); for (i = 0; i < max_cpus; i++) { @@ -1240,6 +1222,19 @@ static void pc_build_feature_control_file(PCMachineState *pcms) fw_cfg_add_file(pcms->fw_cfg, "etc/msr_feature_control", val, sizeof(*val)); } +static void rtc_set_cpus_count(ISADevice *rtc, uint16_t cpus_count) +{ + if (cpus_count > 0xff) { + /* If the number of CPUs can't be represented in 8 bits, the + * BIOS must use "etc/boot-cpus". Set RTC field to 0 just + * to make old BIOSes fail more predictably. + */ + rtc_set_memory(rtc, 0x5f, 0); + } else { + rtc_set_memory(rtc, 0x5f, cpus_count - 1); + } +} + static void pc_machine_done(Notifier *notifier, void *data) { @@ -1248,7 +1243,7 @@ void pc_machine_done(Notifier *notifier, void *data) PCIBus *bus = pcms->bus; /* set the number of CPUs */ - rtc_set_memory(pcms->rtc, 0x5f, pc_present_cpus_count(pcms) - 1); + rtc_set_cpus_count(pcms->rtc, le16_to_cpu(pcms->boot_cpus_le)); if (bus) { int extra_hosts = 0; @@ -1269,8 +1264,28 @@ void pc_machine_done(Notifier *notifier, void *data) acpi_setup(); if (pcms->fw_cfg) { + MachineClass *mc = MACHINE_GET_CLASS(pcms); + pc_build_smbios(pcms->fw_cfg); pc_build_feature_control_file(pcms); + + if (mc->max_cpus > 255) { + fw_cfg_add_file(pcms->fw_cfg, "etc/boot-cpus", &pcms->boot_cpus_le, + sizeof(pcms->boot_cpus_le)); + } + } + + if (pcms->apic_id_limit > 255) { + IntelIOMMUState *iommu = INTEL_IOMMU_DEVICE(x86_iommu_get_default()); + + if (!iommu || !iommu->x86_iommu.intr_supported || + iommu->intr_eim != ON_OFF_AUTO_ON) { + error_report("current -smp configuration requires " + "Extended Interrupt Mode enabled. " + "You can add an IOMMU using: " + "-device intel-iommu,intremap=on,eim=on"); + exit(EXIT_FAILURE); + } } } @@ -1794,9 +1809,11 @@ static void pc_cpu_plug(HotplugHandler *hotplug_dev, } } + /* increment the number of CPUs */ + pcms->boot_cpus_le = cpu_to_le16(le16_to_cpu(pcms->boot_cpus_le) + 1); if (dev->hotplugged) { - /* increment the number of CPUs */ - rtc_set_memory(pcms->rtc, 0x5f, rtc_get_memory(pcms->rtc, 0x5f) + 1); + /* Update the number of CPUs in CMOS */ + rtc_set_cpus_count(pcms->rtc, le16_to_cpu(pcms->boot_cpus_le)); } found_cpu = pc_find_cpu_slot(pcms, CPU(dev), NULL); @@ -1850,7 +1867,10 @@ static void pc_cpu_unplug_cb(HotplugHandler *hotplug_dev, found_cpu->cpu = NULL; object_unparent(OBJECT(dev)); - rtc_set_memory(pcms->rtc, 0x5f, rtc_get_memory(pcms->rtc, 0x5f) - 1); + /* decrement the number of CPUs */ + pcms->boot_cpus_le = cpu_to_le16(le16_to_cpu(pcms->boot_cpus_le) - 1); + /* Update the number of CPUs in CMOS */ + rtc_set_cpus_count(pcms->rtc, le16_to_cpu(pcms->boot_cpus_le)); out: error_propagate(errp, local_err); } |