/* * Verify that CPUs don't have unexpected differences that will cause problems. */ static void cpuinfo_sanity_check(struct cpuinfo_arm64 *cur) { unsigned int cpu = smp_processor_id(); struct cpuinfo_arm64 *boot = &boot_cpu_data; unsigned int diff = 0; /* * The kernel can handle differing I-cache policies, but otherwise * caches should look identical. Userspace JITs will make use of * *minLine. */ diff |= CHECK_MASK(ctr, 0xffff3fff, boot, cur, cpu); /* * Userspace may perform DC ZVA instructions. Mismatched block sizes * could result in too much or too little memory being zeroed if a * process is preempted and migrated between CPUs. */ diff |= CHECK(dczid, boot, cur, cpu); /* If different, timekeeping will be broken (especially with KVM) */ diff |= CHECK(cntfrq, boot, cur, cpu); /* * Even in big.LITTLE, processors should be identical instruction-set * wise. */ diff |= CHECK(id_aa64isar0, boot, cur, cpu); diff |= CHECK(id_aa64isar1, boot, cur, cpu); /* * Differing PARange support is fine as long as all peripherals and * memory are mapped within the minimum PARange of all CPUs. * Linux should not care about secure memory. * ID_AA64MMFR1 is currently RES0. */ diff |= CHECK_MASK(id_aa64mmfr0, 0xffffffffffff0ff0, boot, cur, cpu); diff |= CHECK(id_aa64mmfr1, boot, cur, cpu); /* * EL3 is not our concern. * ID_AA64PFR1 is currently RES0. */ diff |= CHECK_MASK(id_aa64pfr0, 0xffffffffffff0fff, boot, cur, cpu); diff |= CHECK(id_aa64pfr1, boot, cur, cpu); /* * If we have AArch32, we care about 32-bit features for compat. These * registers should be RES0 otherwise. */ diff |= CHECK(id_isar0, boot, cur, cpu); diff |= CHECK(id_isar1, boot, cur, cpu); diff |= CHECK(id_isar2, boot, cur, cpu); diff |= CHECK(id_isar3, boot, cur, cpu); diff |= CHECK(id_isar4, boot, cur, cpu); diff |= CHECK(id_isar5, boot, cur, cpu); diff |= CHECK(id_mmfr0, boot, cur, cpu); diff |= CHECK(id_mmfr1, boot, cur, cpu); diff |= CHECK(id_mmfr2, boot, cur, cpu); diff |= CHECK(id_mmfr3, boot, cur, cpu); diff |= CHECK(id_pfr0, boot, cur, cpu); diff |= CHECK(id_pfr1, boot, cur, cpu); /* * Mismatched CPU features are a recipe for disaster. Don't even * pretend to support them. */ WARN_TAINT_ONCE(diff, TAINT_CPU_OUT_OF_SPEC, "Unsupported CPU feature variation."); }
static void gic_check_cpu_features(void) { WARN_TAINT_ONCE(cpus_have_cap(ARM64_HAS_SYSREG_GIC_CPUIF), TAINT_CPU_OUT_OF_SPEC, "GICv3 system registers enabled, broken firmware!\n"); }
struct dca_provider *ioat_dca_init(struct pci_dev *pdev, void __iomem *iobase) { struct dca_provider *dca; struct ioat_dca_priv *ioatdca; int slots; int i; int err; u16 dca_offset; u16 csi_fsb_control; u16 pcie_control; u8 bit; union { u64 full; struct { u32 low; u32 high; }; } tag_map; if (!system_has_dca_enabled(pdev)) return NULL; dca_offset = readw(iobase + IOAT_DCAOFFSET_OFFSET); if (dca_offset == 0) return NULL; slots = ioat_dca_count_dca_slots(iobase, dca_offset); if (slots == 0) return NULL; dca = alloc_dca_provider(&ioat_dca_ops, sizeof(*ioatdca) + (sizeof(struct ioat_dca_slot) * slots)); if (!dca) return NULL; ioatdca = dca_priv(dca); ioatdca->iobase = iobase; ioatdca->dca_base = iobase + dca_offset; ioatdca->max_requesters = slots; /* some bios might not know to turn these on */ csi_fsb_control = readw(ioatdca->dca_base + IOAT3_CSI_CONTROL_OFFSET); if ((csi_fsb_control & IOAT3_CSI_CONTROL_PREFETCH) == 0) { csi_fsb_control |= IOAT3_CSI_CONTROL_PREFETCH; writew(csi_fsb_control, ioatdca->dca_base + IOAT3_CSI_CONTROL_OFFSET); } pcie_control = readw(ioatdca->dca_base + IOAT3_PCI_CONTROL_OFFSET); if ((pcie_control & IOAT3_PCI_CONTROL_MEMWR) == 0) { pcie_control |= IOAT3_PCI_CONTROL_MEMWR; writew(pcie_control, ioatdca->dca_base + IOAT3_PCI_CONTROL_OFFSET); } /* TODO version, compatibility and configuration checks */ /* copy out the APIC to DCA tag map */ tag_map.low = readl(ioatdca->dca_base + IOAT3_APICID_TAG_MAP_OFFSET_LOW); tag_map.high = readl(ioatdca->dca_base + IOAT3_APICID_TAG_MAP_OFFSET_HIGH); for (i = 0; i < 8; i++) { bit = tag_map.full >> (8 * i); ioatdca->tag_map[i] = bit & DCA_TAG_MAP_MASK; } if (dca3_tag_map_invalid(ioatdca->tag_map)) { WARN_TAINT_ONCE(1, TAINT_FIRMWARE_WORKAROUND, "%s %s: APICID_TAG_MAP set incorrectly by BIOS, disabling DCA\n", dev_driver_string(&pdev->dev), dev_name(&pdev->dev)); free_dca_provider(dca); return NULL; } err = register_dca_provider(dca, &pdev->dev); if (err) { free_dca_provider(dca); return NULL; } return dca; }