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-rw-r--r--arch/x86/kernel/cpu/mce/amd.c1438
1 files changed, 1438 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/mce/amd.c b/arch/x86/kernel/cpu/mce/amd.c
new file mode 100644
index 000000000000..89298c83de53
--- /dev/null
+++ b/arch/x86/kernel/cpu/mce/amd.c
@@ -0,0 +1,1438 @@
+/*
+ * (c) 2005-2016 Advanced Micro Devices, Inc.
+ * Your use of this code is subject to the terms and conditions of the
+ * GNU general public license version 2. See "COPYING" or
+ * http://www.gnu.org/licenses/gpl.html
+ *
+ * Written by Jacob Shin - AMD, Inc.
+ * Maintained by: Borislav Petkov <bp@alien8.de>
+ *
+ * All MC4_MISCi registers are shared between cores on a node.
+ */
+#include <linux/interrupt.h>
+#include <linux/notifier.h>
+#include <linux/kobject.h>
+#include <linux/percpu.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/sysfs.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/cpu.h>
+#include <linux/smp.h>
+#include <linux/string.h>
+
+#include <asm/amd_nb.h>
+#include <asm/traps.h>
+#include <asm/apic.h>
+#include <asm/mce.h>
+#include <asm/msr.h>
+#include <asm/trace/irq_vectors.h>
+
+#include "internal.h"
+
+#define NR_BLOCKS 5
+#define THRESHOLD_MAX 0xFFF
+#define INT_TYPE_APIC 0x00020000
+#define MASK_VALID_HI 0x80000000
+#define MASK_CNTP_HI 0x40000000
+#define MASK_LOCKED_HI 0x20000000
+#define MASK_LVTOFF_HI 0x00F00000
+#define MASK_COUNT_EN_HI 0x00080000
+#define MASK_INT_TYPE_HI 0x00060000
+#define MASK_OVERFLOW_HI 0x00010000
+#define MASK_ERR_COUNT_HI 0x00000FFF
+#define MASK_BLKPTR_LO 0xFF000000
+#define MCG_XBLK_ADDR 0xC0000400
+
+/* Deferred error settings */
+#define MSR_CU_DEF_ERR 0xC0000410
+#define MASK_DEF_LVTOFF 0x000000F0
+#define MASK_DEF_INT_TYPE 0x00000006
+#define DEF_LVT_OFF 0x2
+#define DEF_INT_TYPE_APIC 0x2
+
+/* Scalable MCA: */
+
+/* Threshold LVT offset is at MSR0xC0000410[15:12] */
+#define SMCA_THR_LVT_OFF 0xF000
+
+static bool thresholding_irq_en;
+
+static const char * const th_names[] = {
+ "load_store",
+ "insn_fetch",
+ "combined_unit",
+ "decode_unit",
+ "northbridge",
+ "execution_unit",
+};
+
+static const char * const smca_umc_block_names[] = {
+ "dram_ecc",
+ "misc_umc"
+};
+
+struct smca_bank_name {
+ const char *name; /* Short name for sysfs */
+ const char *long_name; /* Long name for pretty-printing */
+};
+
+static struct smca_bank_name smca_names[] = {
+ [SMCA_LS] = { "load_store", "Load Store Unit" },
+ [SMCA_IF] = { "insn_fetch", "Instruction Fetch Unit" },
+ [SMCA_L2_CACHE] = { "l2_cache", "L2 Cache" },
+ [SMCA_DE] = { "decode_unit", "Decode Unit" },
+ [SMCA_RESERVED] = { "reserved", "Reserved" },
+ [SMCA_EX] = { "execution_unit", "Execution Unit" },
+ [SMCA_FP] = { "floating_point", "Floating Point Unit" },
+ [SMCA_L3_CACHE] = { "l3_cache", "L3 Cache" },
+ [SMCA_CS] = { "coherent_slave", "Coherent Slave" },
+ [SMCA_PIE] = { "pie", "Power, Interrupts, etc." },
+ [SMCA_UMC] = { "umc", "Unified Memory Controller" },
+ [SMCA_PB] = { "param_block", "Parameter Block" },
+ [SMCA_PSP] = { "psp", "Platform Security Processor" },
+ [SMCA_SMU] = { "smu", "System Management Unit" },
+};
+
+static u32 smca_bank_addrs[MAX_NR_BANKS][NR_BLOCKS] __ro_after_init =
+{
+ [0 ... MAX_NR_BANKS - 1] = { [0 ... NR_BLOCKS - 1] = -1 }
+};
+
+static const char *smca_get_name(enum smca_bank_types t)
+{
+ if (t >= N_SMCA_BANK_TYPES)
+ return NULL;
+
+ return smca_names[t].name;
+}
+
+const char *smca_get_long_name(enum smca_bank_types t)
+{
+ if (t >= N_SMCA_BANK_TYPES)
+ return NULL;
+
+ return smca_names[t].long_name;
+}
+EXPORT_SYMBOL_GPL(smca_get_long_name);
+
+static enum smca_bank_types smca_get_bank_type(unsigned int bank)
+{
+ struct smca_bank *b;
+
+ if (bank >= MAX_NR_BANKS)
+ return N_SMCA_BANK_TYPES;
+
+ b = &smca_banks[bank];
+ if (!b->hwid)
+ return N_SMCA_BANK_TYPES;
+
+ return b->hwid->bank_type;
+}
+
+static struct smca_hwid smca_hwid_mcatypes[] = {
+ /* { bank_type, hwid_mcatype, xec_bitmap } */
+
+ /* Reserved type */
+ { SMCA_RESERVED, HWID_MCATYPE(0x00, 0x0), 0x0 },
+
+ /* ZN Core (HWID=0xB0) MCA types */
+ { SMCA_LS, HWID_MCATYPE(0xB0, 0x0), 0x1FFFEF },
+ { SMCA_IF, HWID_MCATYPE(0xB0, 0x1), 0x3FFF },
+ { SMCA_L2_CACHE, HWID_MCATYPE(0xB0, 0x2), 0xF },
+ { SMCA_DE, HWID_MCATYPE(0xB0, 0x3), 0x1FF },
+ /* HWID 0xB0 MCATYPE 0x4 is Reserved */
+ { SMCA_EX, HWID_MCATYPE(0xB0, 0x5), 0x7FF },
+ { SMCA_FP, HWID_MCATYPE(0xB0, 0x6), 0x7F },
+ { SMCA_L3_CACHE, HWID_MCATYPE(0xB0, 0x7), 0xFF },
+
+ /* Data Fabric MCA types */
+ { SMCA_CS, HWID_MCATYPE(0x2E, 0x0), 0x1FF },
+ { SMCA_PIE, HWID_MCATYPE(0x2E, 0x1), 0xF },
+
+ /* Unified Memory Controller MCA type */
+ { SMCA_UMC, HWID_MCATYPE(0x96, 0x0), 0x3F },
+
+ /* Parameter Block MCA type */
+ { SMCA_PB, HWID_MCATYPE(0x05, 0x0), 0x1 },
+
+ /* Platform Security Processor MCA type */
+ { SMCA_PSP, HWID_MCATYPE(0xFF, 0x0), 0x1 },
+
+ /* System Management Unit MCA type */
+ { SMCA_SMU, HWID_MCATYPE(0x01, 0x0), 0x1 },
+};
+
+struct smca_bank smca_banks[MAX_NR_BANKS];
+EXPORT_SYMBOL_GPL(smca_banks);
+
+/*
+ * In SMCA enabled processors, we can have multiple banks for a given IP type.
+ * So to define a unique name for each bank, we use a temp c-string to append
+ * the MCA_IPID[InstanceId] to type's name in get_name().
+ *
+ * InstanceId is 32 bits which is 8 characters. Make sure MAX_MCATYPE_NAME_LEN
+ * is greater than 8 plus 1 (for underscore) plus length of longest type name.
+ */
+#define MAX_MCATYPE_NAME_LEN 30
+static char buf_mcatype[MAX_MCATYPE_NAME_LEN];
+
+static DEFINE_PER_CPU(struct threshold_bank **, threshold_banks);
+static DEFINE_PER_CPU(unsigned int, bank_map); /* see which banks are on */
+
+static void amd_threshold_interrupt(void);
+static void amd_deferred_error_interrupt(void);
+
+static void default_deferred_error_interrupt(void)
+{
+ pr_err("Unexpected deferred interrupt at vector %x\n", DEFERRED_ERROR_VECTOR);
+}
+void (*deferred_error_int_vector)(void) = default_deferred_error_interrupt;
+
+static void smca_configure(unsigned int bank, unsigned int cpu)
+{
+ unsigned int i, hwid_mcatype;
+ struct smca_hwid *s_hwid;
+ u32 high, low;
+ u32 smca_config = MSR_AMD64_SMCA_MCx_CONFIG(bank);
+
+ /* Set appropriate bits in MCA_CONFIG */
+ if (!rdmsr_safe(smca_config, &low, &high)) {
+ /*
+ * OS is required to set the MCAX bit to acknowledge that it is
+ * now using the new MSR ranges and new registers under each
+ * bank. It also means that the OS will configure deferred
+ * errors in the new MCx_CONFIG register. If the bit is not set,
+ * uncorrectable errors will cause a system panic.
+ *
+ * MCA_CONFIG[MCAX] is bit 32 (0 in the high portion of the MSR.)
+ */
+ high |= BIT(0);
+
+ /*
+ * SMCA sets the Deferred Error Interrupt type per bank.
+ *
+ * MCA_CONFIG[DeferredIntTypeSupported] is bit 5, and tells us
+ * if the DeferredIntType bit field is available.
+ *
+ * MCA_CONFIG[DeferredIntType] is bits [38:37] ([6:5] in the
+ * high portion of the MSR). OS should set this to 0x1 to enable
+ * APIC based interrupt. First, check that no interrupt has been
+ * set.
+ */
+ if ((low & BIT(5)) && !((high >> 5) & 0x3))
+ high |= BIT(5);
+
+ wrmsr(smca_config, low, high);
+ }
+
+ /* Return early if this bank was already initialized. */
+ if (smca_banks[bank].hwid)
+ return;
+
+ if (rdmsr_safe_on_cpu(cpu, MSR_AMD64_SMCA_MCx_IPID(bank), &low, &high)) {
+ pr_warn("Failed to read MCA_IPID for bank %d\n", bank);
+ return;
+ }
+
+ hwid_mcatype = HWID_MCATYPE(high & MCI_IPID_HWID,
+ (high & MCI_IPID_MCATYPE) >> 16);
+
+ for (i = 0; i < ARRAY_SIZE(smca_hwid_mcatypes); i++) {
+ s_hwid = &smca_hwid_mcatypes[i];
+ if (hwid_mcatype == s_hwid->hwid_mcatype) {
+ smca_banks[bank].hwid = s_hwid;
+ smca_banks[bank].id = low;
+ smca_banks[bank].sysfs_id = s_hwid->count++;
+ break;
+ }
+ }
+}
+
+struct thresh_restart {
+ struct threshold_block *b;
+ int reset;
+ int set_lvt_off;
+ int lvt_off;
+ u16 old_limit;
+};
+
+static inline bool is_shared_bank(int bank)
+{
+ /*
+ * Scalable MCA provides for only one core to have access to the MSRs of
+ * a shared bank.
+ */
+ if (mce_flags.smca)
+ return false;
+
+ /* Bank 4 is for northbridge reporting and is thus shared */
+ return (bank == 4);
+}
+
+static const char *bank4_names(const struct threshold_block *b)
+{
+ switch (b->address) {
+ /* MSR4_MISC0 */
+ case 0x00000413:
+ return "dram";
+
+ case 0xc0000408:
+ return "ht_links";
+
+ case 0xc0000409:
+ return "l3_cache";
+
+ default:
+ WARN(1, "Funny MSR: 0x%08x\n", b->address);
+ return "";
+ }
+};
+
+
+static bool lvt_interrupt_supported(unsigned int bank, u32 msr_high_bits)
+{
+ /*
+ * bank 4 supports APIC LVT interrupts implicitly since forever.
+ */
+ if (bank == 4)
+ return true;
+
+ /*
+ * IntP: interrupt present; if this bit is set, the thresholding
+ * bank can generate APIC LVT interrupts
+ */
+ return msr_high_bits & BIT(28);
+}
+
+static int lvt_off_valid(struct threshold_block *b, int apic, u32 lo, u32 hi)
+{
+ int msr = (hi & MASK_LVTOFF_HI) >> 20;
+
+ if (apic < 0) {
+ pr_err(FW_BUG "cpu %d, failed to setup threshold interrupt "
+ "for bank %d, block %d (MSR%08X=0x%x%08x)\n", b->cpu,
+ b->bank, b->block, b->address, hi, lo);
+ return 0;
+ }
+
+ if (apic != msr) {
+ /*
+ * On SMCA CPUs, LVT offset is programmed at a different MSR, and
+ * the BIOS provides the value. The original field where LVT offset
+ * was set is reserved. Return early here:
+ */
+ if (mce_flags.smca)
+ return 0;
+
+ pr_err(FW_BUG "cpu %d, invalid threshold interrupt offset %d "
+ "for bank %d, block %d (MSR%08X=0x%x%08x)\n",
+ b->cpu, apic, b->bank, b->block, b->address, hi, lo);
+ return 0;
+ }
+
+ return 1;
+};
+
+/* Reprogram MCx_MISC MSR behind this threshold bank. */
+static void threshold_restart_bank(void *_tr)
+{
+ struct thresh_restart *tr = _tr;
+ u32 hi, lo;
+
+ rdmsr(tr->b->address, lo, hi);
+
+ if (tr->b->threshold_limit < (hi & THRESHOLD_MAX))
+ tr->reset = 1; /* limit cannot be lower than err count */
+
+ if (tr->reset) { /* reset err count and overflow bit */
+ hi =
+ (hi & ~(MASK_ERR_COUNT_HI | MASK_OVERFLOW_HI)) |
+ (THRESHOLD_MAX - tr->b->threshold_limit);
+ } else if (tr->old_limit) { /* change limit w/o reset */
+ int new_count = (hi & THRESHOLD_MAX) +
+ (tr->old_limit - tr->b->threshold_limit);
+
+ hi = (hi & ~MASK_ERR_COUNT_HI) |
+ (new_count & THRESHOLD_MAX);
+ }
+
+ /* clear IntType */
+ hi &= ~MASK_INT_TYPE_HI;
+
+ if (!tr->b->interrupt_capable)
+ goto done;
+
+ if (tr->set_lvt_off) {
+ if (lvt_off_valid(tr->b, tr->lvt_off, lo, hi)) {
+ /* set new lvt offset */
+ hi &= ~MASK_LVTOFF_HI;
+ hi |= tr->lvt_off << 20;
+ }
+ }
+
+ if (tr->b->interrupt_enable)
+ hi |= INT_TYPE_APIC;
+
+ done:
+
+ hi |= MASK_COUNT_EN_HI;
+ wrmsr(tr->b->address, lo, hi);
+}
+
+static void mce_threshold_block_init(struct threshold_block *b, int offset)
+{
+ struct thresh_restart tr = {
+ .b = b,
+ .set_lvt_off = 1,
+ .lvt_off = offset,
+ };
+
+ b->threshold_limit = THRESHOLD_MAX;
+ threshold_restart_bank(&tr);
+};
+
+static int setup_APIC_mce_threshold(int reserved, int new)
+{
+ if (reserved < 0 && !setup_APIC_eilvt(new, THRESHOLD_APIC_VECTOR,
+ APIC_EILVT_MSG_FIX, 0))
+ return new;
+
+ return reserved;
+}
+
+static int setup_APIC_deferred_error(int reserved, int new)
+{
+ if (reserved < 0 && !setup_APIC_eilvt(new, DEFERRED_ERROR_VECTOR,
+ APIC_EILVT_MSG_FIX, 0))
+ return new;
+
+ return reserved;
+}
+
+static void deferred_error_interrupt_enable(struct cpuinfo_x86 *c)
+{
+ u32 low = 0, high = 0;
+ int def_offset = -1, def_new;
+
+ if (rdmsr_safe(MSR_CU_DEF_ERR, &low, &high))
+ return;
+
+ def_new = (low & MASK_DEF_LVTOFF) >> 4;
+ if (!(low & MASK_DEF_LVTOFF)) {
+ pr_err(FW_BUG "Your BIOS is not setting up LVT offset 0x2 for deferred error IRQs correctly.\n");
+ def_new = DEF_LVT_OFF;
+ low = (low & ~MASK_DEF_LVTOFF) | (DEF_LVT_OFF << 4);
+ }
+
+ def_offset = setup_APIC_deferred_error(def_offset, def_new);
+ if ((def_offset == def_new) &&
+ (deferred_error_int_vector != amd_deferred_error_interrupt))
+ deferred_error_int_vector = amd_deferred_error_interrupt;
+
+ if (!mce_flags.smca)
+ low = (low & ~MASK_DEF_INT_TYPE) | DEF_INT_TYPE_APIC;
+
+ wrmsr(MSR_CU_DEF_ERR, low, high);
+}
+
+static u32 smca_get_block_address(unsigned int bank, unsigned int block)
+{
+ u32 low, high;
+ u32 addr = 0;
+
+ if (smca_get_bank_type(bank) == SMCA_RESERVED)
+ return addr;
+
+ if (!block)
+ return MSR_AMD64_SMCA_MCx_MISC(bank);
+
+ /* Check our cache first: */
+ if (smca_bank_addrs[bank][block] != -1)
+ return smca_bank_addrs[bank][block];
+
+ /*
+ * For SMCA enabled processors, BLKPTR field of the first MISC register
+ * (MCx_MISC0) indicates presence of additional MISC regs set (MISC1-4).
+ */
+ if (rdmsr_safe(MSR_AMD64_SMCA_MCx_CONFIG(bank), &low, &high))
+ goto out;
+
+ if (!(low & MCI_CONFIG_MCAX))
+ goto out;
+
+ if (!rdmsr_safe(MSR_AMD64_SMCA_MCx_MISC(bank), &low, &high) &&
+ (low & MASK_BLKPTR_LO))
+ addr = MSR_AMD64_SMCA_MCx_MISCy(bank, block - 1);
+
+out:
+ smca_bank_addrs[bank][block] = addr;
+ return addr;
+}
+
+static u32 get_block_address(u32 current_addr, u32 low, u32 high,
+ unsigned int bank, unsigned int block)
+{
+ u32 addr = 0, offset = 0;
+
+ if ((bank >= mca_cfg.banks) || (block >= NR_BLOCKS))
+ return addr;
+
+ if (mce_flags.smca)
+ return smca_get_block_address(bank, block);
+
+ /* Fall back to method we used for older processors: */
+ switch (block) {
+ case 0:
+ addr = msr_ops.misc(bank);
+ break;
+ case 1:
+ offset = ((low & MASK_BLKPTR_LO) >> 21);
+ if (offset)
+ addr = MCG_XBLK_ADDR + offset;
+ break;
+ default:
+ addr = ++current_addr;
+ }
+ return addr;
+}
+
+static int
+prepare_threshold_block(unsigned int bank, unsigned int block, u32 addr,
+ int offset, u32 misc_high)
+{
+ unsigned int cpu = smp_processor_id();
+ u32 smca_low, smca_high;
+ struct threshold_block b;
+ int new;
+
+ if (!block)
+ per_cpu(bank_map, cpu) |= (1 << bank);
+
+ memset(&b, 0, sizeof(b));
+ b.cpu = cpu;
+ b.bank = bank;
+ b.block = block;
+ b.address = addr;
+ b.interrupt_capable = lvt_interrupt_supported(bank, misc_high);
+
+ if (!b.interrupt_capable)
+ goto done;
+
+ b.interrupt_enable = 1;
+
+ if (!mce_flags.smca) {
+ new = (misc_high & MASK_LVTOFF_HI) >> 20;
+ goto set_offset;
+ }
+
+ /* Gather LVT offset for thresholding: */
+ if (rdmsr_safe(MSR_CU_DEF_ERR, &smca_low, &smca_high))
+ goto out;
+
+ new = (smca_low & SMCA_THR_LVT_OFF) >> 12;
+
+set_offset:
+ offset = setup_APIC_mce_threshold(offset, new);
+ if (offset == new)
+ thresholding_irq_en = true;
+
+done:
+ mce_threshold_block_init(&b, offset);
+
+out:
+ return offset;
+}
+
+/* cpu init entry point, called from mce.c with preempt off */
+void mce_amd_feature_init(struct cpuinfo_x86 *c)
+{
+ u32 low = 0, high = 0, address = 0;
+ unsigned int bank, block, cpu = smp_processor_id();
+ int offset = -1;
+
+ for (bank = 0; bank < mca_cfg.banks; ++bank) {
+ if (mce_flags.smca)
+ smca_configure(bank, cpu);
+
+ for (block = 0; block < NR_BLOCKS; ++block) {
+ address = get_block_address(address, low, high, bank, block);
+ if (!address)
+ break;
+
+ if (rdmsr_safe(address, &low, &high))
+ break;
+
+ if (!(high & MASK_VALID_HI))
+ continue;
+
+ if (!(high & MASK_CNTP_HI) ||
+ (high & MASK_LOCKED_HI))
+ continue;
+
+ offset = prepare_threshold_block(bank, block, address, offset, high);
+ }
+ }
+
+ if (mce_flags.succor)
+ deferred_error_interrupt_enable(c);
+}
+
+int umc_normaddr_to_sysaddr(u64 norm_addr, u16 nid, u8 umc, u64 *sys_addr)
+{
+ u64 dram_base_addr, dram_limit_addr, dram_hole_base;
+ /* We start from the normalized address */
+ u64 ret_addr = norm_addr;
+
+ u32 tmp;
+
+ u8 die_id_shift, die_id_mask, socket_id_shift, socket_id_mask;
+ u8 intlv_num_dies, intlv_num_chan, intlv_num_sockets;
+ u8 intlv_addr_sel, intlv_addr_bit;
+ u8 num_intlv_bits, hashed_bit;
+ u8 lgcy_mmio_hole_en, base = 0;
+ u8 cs_mask, cs_id = 0;
+ bool hash_enabled = false;
+
+ /* Read D18F0x1B4 (DramOffset), check if base 1 is used. */
+ if (amd_df_indirect_read(nid, 0, 0x1B4, umc, &tmp))
+ goto out_err;
+
+ /* Remove HiAddrOffset from normalized address, if enabled: */
+ if (tmp & BIT(0)) {
+ u64 hi_addr_offset = (tmp & GENMASK_ULL(31, 20)) << 8;
+
+ if (norm_addr >= hi_addr_offset) {
+ ret_addr -= hi_addr_offset;
+ base = 1;
+ }
+ }
+
+ /* Read D18F0x110 (DramBaseAddress). */
+ if (amd_df_indirect_read(nid, 0, 0x110 + (8 * base), umc, &tmp))
+ goto out_err;
+
+ /* Check if address range is valid. */
+ if (!(tmp & BIT(0))) {
+ pr_err("%s: Invalid DramBaseAddress range: 0x%x.\n",
+ __func__, tmp);
+ goto out_err;
+ }
+
+ lgcy_mmio_hole_en = tmp & BIT(1);
+ intlv_num_chan = (tmp >> 4) & 0xF;
+ intlv_addr_sel = (tmp >> 8) & 0x7;
+ dram_base_addr = (tmp & GENMASK_ULL(31, 12)) << 16;
+
+ /* {0, 1, 2, 3} map to address bits {8, 9, 10, 11} respectively */
+ if (intlv_addr_sel > 3) {
+ pr_err("%s: Invalid interleave address select %d.\n",
+ __func__, intlv_addr_sel);
+ goto out_err;
+ }
+
+ /* Read D18F0x114 (DramLimitAddress). */
+ if (amd_df_indirect_read(nid, 0, 0x114 + (8 * base), umc, &tmp))
+ goto out_err;
+
+ intlv_num_sockets = (tmp >> 8) & 0x1;
+ intlv_num_dies = (tmp >> 10) & 0x3;
+ dram_limit_addr = ((tmp & GENMASK_ULL(31, 12)) << 16) | GENMASK_ULL(27, 0);
+
+ intlv_addr_bit = intlv_addr_sel + 8;
+
+ /* Re-use intlv_num_chan by setting it equal to log2(#channels) */
+ switch (intlv_num_chan) {
+ case 0: intlv_num_chan = 0; break;
+ case 1: intlv_num_chan = 1; break;
+ case 3: intlv_num_chan = 2; break;
+ case 5: intlv_num_chan = 3; break;
+ case 7: intlv_num_chan = 4; break;
+
+ case 8: intlv_num_chan = 1;
+ hash_enabled = true;
+ break;
+ default:
+ pr_err("%s: Invalid number of interleaved channels %d.\n",
+ __func__, intlv_num_chan);
+ goto out_err;
+ }
+
+ num_intlv_bits = intlv_num_chan;
+
+ if (intlv_num_dies > 2) {
+ pr_err("%s: Invalid number of interleaved nodes/dies %d.\n",
+ __func__, intlv_num_dies);
+ goto out_err;
+ }
+
+ num_intlv_bits += intlv_num_dies;
+
+ /* Add a bit if sockets are interleaved. */
+ num_intlv_bits += intlv_num_sockets;
+
+ /* Assert num_intlv_bits <= 4 */
+ if (num_intlv_bits > 4) {
+ pr_err("%s: Invalid interleave bits %d.\n",
+ __func__, num_intlv_bits);
+ goto out_err;
+ }
+
+ if (num_intlv_bits > 0) {
+ u64 temp_addr_x, temp_addr_i, temp_addr_y;
+ u8 die_id_bit, sock_id_bit, cs_fabric_id;
+
+ /*
+ * Read FabricBlockInstanceInformation3_CS[BlockFabricID].
+ * This is the fabric id for this coherent slave. Use
+ * umc/channel# as instance id of the coherent slave
+ * for FICAA.
+ */
+ if (amd_df_indirect_read(nid, 0, 0x50, umc, &tmp))
+ goto out_err;
+
+ cs_fabric_id = (tmp >> 8) & 0xFF;
+ die_id_bit = 0;
+
+ /* If interleaved over more than 1 channel: */
+ if (intlv_num_chan) {
+ die_id_bit = intlv_num_chan;
+ cs_mask = (1 << die_id_bit) - 1;
+ cs_id = cs_fabric_id & cs_mask;
+ }
+
+ sock_id_bit = die_id_bit;
+
+ /* Read D18F1x208 (SystemFabricIdMask). */
+ if (intlv_num_dies || intlv_num_sockets)
+ if (amd_df_indirect_read(nid, 1, 0x208, umc, &tmp))
+ goto out_err;
+
+ /* If interleaved over more than 1 die. */
+ if (intlv_num_dies) {
+ sock_id_bit = die_id_bit + intlv_num_dies;
+ die_id_shift = (tmp >> 24) & 0xF;
+ die_id_mask = (tmp >> 8) & 0xFF;
+
+ cs_id |= ((cs_fabric_id & die_id_mask) >> die_id_shift) << die_id_bit;
+ }
+
+ /* If interleaved over more than 1 socket. */
+ if (intlv_num_sockets) {
+ socket_id_shift = (tmp >> 28) & 0xF;
+ socket_id_mask = (tmp >> 16) & 0xFF;
+
+ cs_id |= ((cs_fabric_id & socket_id_mask) >> socket_id_shift) << sock_id_bit;
+ }
+
+ /*
+ * The pre-interleaved address consists of XXXXXXIIIYYYYY
+ * where III is the ID for this CS, and XXXXXXYYYYY are the
+ * address bits from the post-interleaved address.
+ * "num_intlv_bits" has been calculated to tell us how many "I"
+ * bits there are. "intlv_addr_bit" tells us how many "Y" bits
+ * there are (where "I" starts).
+ */
+ temp_addr_y = ret_addr & GENMASK_ULL(intlv_addr_bit-1, 0);
+ temp_addr_i = (cs_id << intlv_addr_bit);
+ temp_addr_x = (ret_addr & GENMASK_ULL(63, intlv_addr_bit)) << num_intlv_bits;
+ ret_addr = temp_addr_x | temp_addr_i | temp_addr_y;
+ }
+
+ /* Add dram base address */
+ ret_addr += dram_base_addr;
+
+ /* If legacy MMIO hole enabled */
+ if (lgcy_mmio_hole_en) {
+ if (amd_df_indirect_read(nid, 0, 0x104, umc, &tmp))
+ goto out_err;
+
+ dram_hole_base = tmp & GENMASK(31, 24);
+ if (ret_addr >= dram_hole_base)
+ ret_addr += (BIT_ULL(32) - dram_hole_base);
+ }
+
+ if (hash_enabled) {
+ /* Save some parentheses and grab ls-bit at the end. */
+ hashed_bit = (ret_addr >> 12) ^
+ (ret_addr >> 18) ^
+ (ret_addr >> 21) ^
+ (ret_addr >> 30) ^
+ cs_id;
+
+ hashed_bit &= BIT(0);
+
+ if (hashed_bit != ((ret_addr >> intlv_addr_bit) & BIT(0)))
+ ret_addr ^= BIT(intlv_addr_bit);
+ }
+
+ /* Is calculated system address is above DRAM limit address? */
+ if (ret_addr > dram_limit_addr)
+ goto out_err;
+
+ *sys_addr = ret_addr;
+ return 0;
+
+out_err:
+ return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(umc_normaddr_to_sysaddr);
+
+bool amd_mce_is_memory_error(struct mce *m)
+{
+ /* ErrCodeExt[20:16] */
+ u8 xec = (m->status >> 16) & 0x1f;
+
+ if (mce_flags.smca)
+ return smca_get_bank_type(m->bank) == SMCA_UMC && xec == 0x0;
+
+ return m->bank == 4 && xec == 0x8;
+}
+
+static void __log_error(unsigned int bank, u64 status, u64 addr, u64 misc)
+{
+ struct mce m;
+
+ mce_setup(&m);
+
+ m.status = status;
+ m.misc = misc;
+ m.bank = bank;
+ m.tsc = rdtsc();
+
+ if (m.status & MCI_STATUS_ADDRV) {
+ m.addr = addr;
+
+ /*
+ * Extract [55:<lsb>] where lsb is the least significant
+ * *valid* bit of the address bits.
+ */
+ if (mce_flags.smca) {
+ u8 lsb = (m.addr >> 56) & 0x3f;
+
+ m.addr &= GENMASK_ULL(55, lsb);
+ }
+ }
+
+ if (mce_flags.smca) {
+ rdmsrl(MSR_AMD64_SMCA_MCx_IPID(bank), m.ipid);
+
+ if (m.status & MCI_STATUS_SYNDV)
+ rdmsrl(MSR_AMD64_SMCA_MCx_SYND(bank), m.synd);
+ }
+
+ mce_log(&m);
+}
+
+asmlinkage __visible void __irq_entry smp_deferred_error_interrupt(struct pt_regs *regs)
+{
+ entering_irq();
+ trace_deferred_error_apic_entry(DEFERRED_ERROR_VECTOR);
+ inc_irq_stat(irq_deferred_error_count);
+ deferred_error_int_vector();
+ trace_deferred_error_apic_exit(DEFERRED_ERROR_VECTOR);
+ exiting_ack_irq();
+}
+
+/*
+ * Returns true if the logged error is deferred. False, otherwise.
+ */
+static inline bool
+_log_error_bank(unsigned int bank, u32 msr_stat, u32 msr_addr, u64 misc)
+{
+ u64 status, addr = 0;
+
+ rdmsrl(msr_stat, status);
+ if (!(status & MCI_STATUS_VAL))
+ return false;
+
+ if (status & MCI_STATUS_ADDRV)
+ rdmsrl(msr_addr, addr);
+
+ __log_error(bank, status, addr, misc);
+
+ wrmsrl(msr_stat, 0);
+
+ return status & MCI_STATUS_DEFERRED;
+}
+
+/*
+ * We have three scenarios for checking for Deferred errors:
+ *
+ * 1) Non-SMCA systems check MCA_STATUS and log error if found.
+ * 2) SMCA systems check MCA_STATUS. If error is found then log it and also
+ * clear MCA_DESTAT.
+ * 3) SMCA systems check MCA_DESTAT, if error was not found in MCA_STATUS, and
+ * log it.
+ */
+static void log_error_deferred(unsigned int bank)
+{
+ bool defrd;
+
+ defrd = _log_error_bank(bank, msr_ops.status(bank),
+ msr_ops.addr(bank), 0);
+
+ if (!mce_flags.smca)
+ return;
+
+ /* Clear MCA_DESTAT if we logged the deferred error from MCA_STATUS. */
+ if (defrd) {
+ wrmsrl(MSR_AMD64_SMCA_MCx_DESTAT(bank), 0);
+ return;
+ }
+
+ /*
+ * Only deferred errors are logged in MCA_DE{STAT,ADDR} so just check
+ * for a valid error.
+ */
+ _log_error_bank(bank, MSR_AMD64_SMCA_MCx_DESTAT(bank),
+ MSR_AMD64_SMCA_MCx_DEADDR(bank), 0);
+}
+
+/* APIC interrupt handler for deferred errors */
+static void amd_deferred_error_interrupt(void)
+{
+ unsigned int bank;
+
+ for (bank = 0; bank < mca_cfg.banks; ++bank)
+ log_error_deferred(bank);
+}
+
+static void log_error_thresholding(unsigned int bank, u64 misc)
+{
+ _log_error_bank(bank, msr_ops.status(bank), msr_ops.addr(bank), misc);
+}
+
+static void log_and_reset_block(struct threshold_block *block)
+{
+ struct thresh_restart tr;
+ u32 low = 0, high = 0;
+
+ if (!block)
+ return;
+
+ if (rdmsr_safe(block->address, &low, &high))
+ return;
+
+ if (!(high & MASK_OVERFLOW_HI))
+ return;
+
+ /* Log the MCE which caused the threshold event. */
+ log_error_thresholding(block->bank, ((u64)high << 32) | low);
+
+ /* Reset threshold block after logging error. */
+ memset(&tr, 0, sizeof(tr));
+ tr.b = block;
+ threshold_restart_bank(&tr);
+}
+
+/*
+ * Threshold interrupt handler will service THRESHOLD_APIC_VECTOR. The interrupt
+ * goes off when error_count reaches threshold_limit.
+ */
+static void amd_threshold_interrupt(void)
+{
+ struct threshold_block *first_block = NULL, *block = NULL, *tmp = NULL;
+ unsigned int bank, cpu = smp_processor_id();
+
+ for (bank = 0; bank < mca_cfg.banks; ++bank) {
+ if (!(per_cpu(bank_map, cpu) & (1 << bank)))
+ continue;
+
+ first_block = per_cpu(threshold_banks, cpu)[bank]->blocks;
+ if (!first_block)
+ continue;
+
+ /*
+ * The first block is also the head of the list. Check it first
+ * before iterating over the rest.
+ */
+ log_and_reset_block(first_block);
+ list_for_each_entry_safe(block, tmp, &first_block->miscj, miscj)
+ log_and_reset_block(block);
+ }
+}
+
+/*
+ * Sysfs Interface
+ */
+
+struct threshold_attr {
+ struct attribute attr;
+ ssize_t (*show) (struct threshold_block *, char *);
+ ssize_t (*store) (struct threshold_block *, const char *, size_t count);
+};
+
+#define SHOW_FIELDS(name) \
+static ssize_t show_ ## name(struct threshold_block *b, char *buf) \
+{ \
+ return sprintf(buf, "%lu\n", (unsigned long) b->name); \
+}
+SHOW_FIELDS(interrupt_enable)
+SHOW_FIELDS(threshold_limit)
+
+static ssize_t
+store_interrupt_enable(struct threshold_block *b, const char *buf, size_t size)
+{
+ struct thresh_restart tr;
+ unsigned long new;
+
+ if (!b->interrupt_capable)
+ return -EINVAL;
+
+ if (kstrtoul(buf, 0, &new) < 0)
+ return -EINVAL;
+
+ b->interrupt_enable = !!new;
+
+ memset(&tr, 0, sizeof(tr));
+ tr.b = b;
+
+ smp_call_function_single(b->cpu, threshold_restart_bank, &tr, 1);
+
+ return size;
+}
+
+static ssize_t
+store_threshold_limit(struct threshold_block *b, const char *buf, size_t size)
+{
+ struct thresh_restart tr;
+ unsigned long new;
+
+ if (kstrtoul(buf, 0, &new) < 0)
+ return -EINVAL;
+
+ if (new > THRESHOLD_MAX)
+ new = THRESHOLD_MAX;
+ if (new < 1)
+ new = 1;
+
+ memset(&tr, 0, sizeof(tr));
+ tr.old_limit = b->threshold_limit;
+ b->threshold_limit = new;
+ tr.b = b;
+
+ smp_call_function_single(b->cpu, threshold_restart_bank, &tr, 1);
+
+ return size;
+}
+
+static ssize_t show_error_count(struct threshold_block *b, char *buf)
+{
+ u32 lo, hi;
+
+ rdmsr_on_cpu(b->cpu, b->address, &lo, &hi);
+
+ return sprintf(buf, "%u\n", ((hi & THRESHOLD_MAX) -
+ (THRESHOLD_MAX - b->threshold_limit)));
+}
+
+static struct threshold_attr error_count = {
+ .attr = {.name = __stringify(error_count), .mode = 0444 },
+ .show = show_error_count,
+};
+
+#define RW_ATTR(val) \
+static struct threshold_attr val = { \
+ .attr = {.name = __stringify(val), .mode = 0644 }, \
+ .show = show_## val, \
+ .store = store_## val, \
+};
+
+RW_ATTR(interrupt_enable);
+RW_ATTR(threshold_limit);
+
+static struct attribute *default_attrs[] = {
+ &threshold_limit.attr,
+ &error_count.attr,
+ NULL, /* possibly interrupt_enable if supported, see below */
+ NULL,
+};
+
+#define to_block(k) container_of(k, struct threshold_block, kobj)
+#define to_attr(a) container_of(a, struct threshold_attr, attr)
+
+static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf)
+{
+ struct threshold_block *b = to_block(kobj);
+ struct threshold_attr *a = to_attr(attr);
+ ssize_t ret;
+
+ ret = a->show ? a->show(b, buf) : -EIO;
+
+ return ret;
+}
+
+static ssize_t store(struct kobject *kobj, struct attribute *attr,
+ const char *buf, size_t count)
+{
+ struct threshold_block *b = to_block(kobj);
+ struct threshold_attr *a = to_attr(attr);
+ ssize_t ret;
+
+ ret = a->store ? a->store(b, buf, count) : -EIO;
+
+ return ret;
+}
+
+static const struct sysfs_ops threshold_ops = {
+ .show = show,
+ .store = store,
+};
+
+static struct kobj_type threshold_ktype = {
+ .sysfs_ops = &threshold_ops,
+ .default_attrs = default_attrs,
+};
+
+static const char *get_name(unsigned int bank, struct threshold_block *b)
+{
+ enum smca_bank_types bank_type;
+
+ if (!mce_flags.smca) {
+ if (b && bank == 4)
+ return bank4_names(b);
+
+ return th_names[bank];
+ }
+
+ bank_type = smca_get_bank_type(bank);
+ if (bank_type >= N_SMCA_BANK_TYPES)
+ return NULL;
+
+ if (b && bank_type == SMCA_UMC) {
+ if (b->block < ARRAY_SIZE(smca_umc_block_names))
+ return smca_umc_block_names[b->block];
+ return NULL;
+ }
+
+ if (smca_banks[bank].hwid->count == 1)
+ return smca_get_name(bank_type);
+
+ snprintf(buf_mcatype, MAX_MCATYPE_NAME_LEN,
+ "%s_%x", smca_get_name(bank_type),
+ smca_banks[bank].sysfs_id);
+ return buf_mcatype;
+}
+
+static int allocate_threshold_blocks(unsigned int cpu, unsigned int bank,
+ unsigned int block, u32 address)
+{
+ struct threshold_block *b = NULL;
+ u32 low, high;
+ int err;
+
+ if ((bank >= mca_cfg.banks) || (block >= NR_BLOCKS))
+ return 0;
+
+ if (rdmsr_safe_on_cpu(cpu, address, &low, &high))
+ return 0;
+
+ if (!(high & MASK_VALID_HI)) {
+ if (block)
+ goto recurse;
+ else
+ return 0;
+ }
+
+ if (!(high & MASK_CNTP_HI) ||
+ (high & MASK_LOCKED_HI))
+ goto recurse;
+
+ b = kzalloc(sizeof(struct threshold_block), GFP_KERNEL);
+ if (!b)
+ return -ENOMEM;
+
+ b->block = block;
+ b->bank = bank;
+ b->cpu = cpu;
+ b->address = address;
+ b->interrupt_enable = 0;
+ b->interrupt_capable = lvt_interrupt_supported(bank, high);
+ b->threshold_limit = THRESHOLD_MAX;
+
+ if (b->interrupt_capable) {
+ threshold_ktype.default_attrs[2] = &interrupt_enable.attr;
+ b->interrupt_enable = 1;
+ } else {
+ threshold_ktype.default_attrs[2] = NULL;
+ }
+
+ INIT_LIST_HEAD(&b->miscj);
+
+ if (per_cpu(threshold_banks, cpu)[bank]->blocks) {
+ list_add(&b->miscj,
+ &per_cpu(threshold_banks, cpu)[bank]->blocks->miscj);
+ } else {
+ per_cpu(threshold_banks, cpu)[bank]->blocks = b;
+ }
+
+ err = kobject_init_and_add(&b->kobj, &threshold_ktype,
+ per_cpu(threshold_banks, cpu)[bank]->kobj,
+ get_name(bank, b));
+ if (err)
+ goto out_free;
+recurse:
+ address = get_block_address(address, low, high, bank, ++block);
+ if (!address)
+ return 0;
+
+ err = allocate_threshold_blocks(cpu, bank, block, address);
+ if (err)
+ goto out_free;
+
+ if (b)
+ kobject_uevent(&b->kobj, KOBJ_ADD);
+
+ return err;
+
+out_free:
+ if (b) {
+ kobject_put(&b->kobj);
+ list_del(&b->miscj);
+ kfree(b);
+ }
+ return err;
+}
+
+static int __threshold_add_blocks(struct threshold_bank *b)
+{
+ struct list_head *head = &b->blocks->miscj;
+ struct threshold_block *pos = NULL;
+ struct threshold_block *tmp = NULL;
+ int err = 0;
+
+ err = kobject_add(&b->blocks->kobj, b->kobj, b->blocks->kobj.name);
+ if (err)
+ return err;
+
+ list_for_each_entry_safe(pos, tmp, head, miscj) {
+
+ err = kobject_add(&pos->kobj, b->kobj, pos->kobj.name);
+ if (err) {
+ list_for_each_entry_safe_reverse(pos, tmp, head, miscj)
+ kobject_del(&pos->kobj);
+
+ return err;
+ }
+ }
+ return err;
+}
+
+static int threshold_create_bank(unsigned int cpu, unsigned int bank)
+{
+ struct device *dev = per_cpu(mce_device, cpu);
+ struct amd_northbridge *nb = NULL;
+ struct threshold_bank *b = NULL;
+ const char *name = get_name(bank, NULL);
+ int err = 0;
+
+ if (!dev)
+ return -ENODEV;
+
+ if (is_shared_bank(bank)) {
+ nb = node_to_amd_nb(amd_get_nb_id(cpu));
+
+ /* threshold descriptor already initialized on this node? */
+ if (nb && nb->bank4) {
+ /* yes, use it */
+ b = nb->bank4;
+ err = kobject_add(b->kobj, &dev->kobj, name);
+ if (err)
+ goto out;
+
+ per_cpu(threshold_banks, cpu)[bank] = b;
+ refcount_inc(&b->cpus);
+
+ err = __threshold_add_blocks(b);
+
+ goto out;
+ }
+ }
+
+ b = kzalloc(sizeof(struct threshold_bank), GFP_KERNEL);
+ if (!b) {
+ err = -ENOMEM;
+ goto out;
+ }
+
+ b->kobj = kobject_create_and_add(name, &dev->kobj);
+ if (!b->kobj) {
+ err = -EINVAL;
+ goto out_free;
+ }
+
+ per_cpu(threshold_banks, cpu)[bank] = b;
+
+ if (is_shared_bank(bank)) {
+ refcount_set(&b->cpus, 1);
+
+ /* nb is already initialized, see above */
+ if (nb) {
+ WARN_ON(nb->bank4);
+ nb->bank4 = b;
+ }
+ }
+
+ err = allocate_threshold_blocks(cpu, bank, 0, msr_ops.misc(bank));
+ if (!err)
+ goto out;
+
+ out_free:
+ kfree(b);
+
+ out:
+ return err;
+}
+
+static void deallocate_threshold_block(unsigned int cpu,
+ unsigned int bank)
+{
+ struct threshold_block *pos = NULL;
+ struct threshold_block *tmp = NULL;
+ struct threshold_bank *head = per_cpu(threshold_banks, cpu)[bank];
+
+ if (!head)
+ return;
+
+ list_for_each_entry_safe(pos, tmp, &head->blocks->miscj, miscj) {
+ kobject_put(&pos->kobj);
+ list_del(&pos->miscj);
+ kfree(pos);
+ }
+
+ kfree(per_cpu(threshold_banks, cpu)[bank]->blocks);
+ per_cpu(threshold_banks, cpu)[bank]->blocks = NULL;
+}
+
+static void __threshold_remove_blocks(struct threshold_bank *b)
+{
+ struct threshold_block *pos = NULL;
+ struct threshold_block *tmp = NULL;
+
+ kobject_del(b->kobj);
+
+ list_for_each_entry_safe(pos, tmp, &b->blocks->miscj, miscj)
+ kobject_del(&pos->kobj);
+}
+
+static void threshold_remove_bank(unsigned int cpu, int bank)
+{
+ struct amd_northbridge *nb;
+ struct threshold_bank *b;
+
+ b = per_cpu(threshold_banks, cpu)[bank];
+ if (!b)
+ return;
+
+ if (!b->blocks)
+ goto free_out;
+
+ if (is_shared_bank(bank)) {
+ if (!refcount_dec_and_test(&b->cpus)) {
+ __threshold_remove_blocks(b);
+ per_cpu(threshold_banks, cpu)[bank] = NULL;
+ return;
+ } else {
+ /*
+ * the last CPU on this node using the shared bank is
+ * going away, remove that bank now.
+ */
+ nb = node_to_amd_nb(amd_get_nb_id(cpu));
+ nb->bank4 = NULL;
+ }
+ }
+
+ deallocate_threshold_block(cpu, bank);
+
+free_out:
+ kobject_del(b->kobj);
+ kobject_put(b->kobj);
+ kfree(b);
+ per_cpu(threshold_banks, cpu)[bank] = NULL;
+}
+
+int mce_threshold_remove_device(unsigned int cpu)
+{
+ unsigned int bank;
+
+ for (bank = 0; bank < mca_cfg.banks; ++bank) {
+ if (!(per_cpu(bank_map, cpu) & (1 << bank)))
+ continue;
+ threshold_remove_bank(cpu, bank);
+ }
+ kfree(per_cpu(threshold_banks, cpu));
+ per_cpu(threshold_banks, cpu) = NULL;
+ return 0;
+}
+
+/* create dir/files for all valid threshold banks */
+int mce_threshold_create_device(unsigned int cpu)
+{
+ unsigned int bank;
+ struct threshold_bank **bp;
+ int err = 0;
+
+ bp = per_cpu(threshold_banks, cpu);
+ if (bp)
+ return 0;
+
+ bp = kcalloc(mca_cfg.banks, sizeof(struct threshold_bank *),
+ GFP_KERNEL);
+ if (!bp)
+ return -ENOMEM;
+
+ per_cpu(threshold_banks, cpu) = bp;
+
+ for (bank = 0; bank < mca_cfg.banks; ++bank) {
+ if (!(per_cpu(bank_map, cpu) & (1 << bank)))
+ continue;
+ err = threshold_create_bank(cpu, bank);
+ if (err)
+ goto err;
+ }
+ return err;
+err:
+ mce_threshold_remove_device(cpu);
+ return err;
+}
+
+static __init int threshold_init_device(void)
+{
+ unsigned lcpu = 0;
+
+ /* to hit CPUs online before the notifier is up */
+ for_each_online_cpu(lcpu) {
+ int err = mce_threshold_create_device(lcpu);
+
+ if (err)
+ return err;
+ }
+
+ if (thresholding_irq_en)
+ mce_threshold_vector = amd_threshold_interrupt;
+
+ return 0;
+}
+/*
+ * there are 3 funcs which need to be _initcalled in a logic sequence:
+ * 1. xen_late_init_mcelog
+ * 2. mcheck_init_device
+ * 3. threshold_init_device
+ *
+ * xen_late_init_mcelog must register xen_mce_chrdev_device before
+ * native mce_chrdev_device registration if running under xen platform;
+ *
+ * mcheck_init_device should be inited before threshold_init_device to
+ * initialize mce_device, otherwise a NULL ptr dereference will cause panic.
+ *
+ * so we use following _initcalls
+ * 1. device_initcall(xen_late_init_mcelog);
+ * 2. device_initcall_sync(mcheck_init_device);
+ * 3. late_initcall(threshold_init_device);
+ *
+ * when running under xen, the initcall order is 1,2,3;
+ * on baremetal, we skip 1 and we do only 2 and 3.
+ */
+late_initcall(threshold_init_device);