| // SPDX-License-Identifier: GPL-2.0-only | 
 | /* | 
 |  * Extended Error Log driver | 
 |  * | 
 |  * Copyright (C) 2013 Intel Corp. | 
 |  * Author: Chen, Gong <gong.chen@intel.com> | 
 |  */ | 
 |  | 
 | #include <linux/module.h> | 
 | #include <linux/acpi.h> | 
 | #include <linux/cper.h> | 
 | #include <linux/ratelimit.h> | 
 | #include <linux/edac.h> | 
 | #include <linux/ras.h> | 
 | #include <asm/cpu.h> | 
 | #include <asm/mce.h> | 
 |  | 
 | #include "apei/apei-internal.h" | 
 | #include <ras/ras_event.h> | 
 |  | 
 | #define EXT_ELOG_ENTRY_MASK	GENMASK_ULL(51, 0) /* elog entry address mask */ | 
 |  | 
 | #define EXTLOG_DSM_REV		0x0 | 
 | #define	EXTLOG_FN_ADDR		0x1 | 
 |  | 
 | #define FLAG_OS_OPTIN		BIT(0) | 
 | #define ELOG_ENTRY_VALID	(1ULL<<63) | 
 | #define ELOG_ENTRY_LEN		0x1000 | 
 |  | 
 | #define EMCA_BUG \ | 
 | 	"Can not request iomem region <0x%016llx-0x%016llx> - eMCA disabled\n" | 
 |  | 
 | struct extlog_l1_head { | 
 | 	u32 ver;	/* Header Version */ | 
 | 	u32 hdr_len;	/* Header Length */ | 
 | 	u64 total_len;	/* entire L1 Directory length including this header */ | 
 | 	u64 elog_base;	/* MCA Error Log Directory base address */ | 
 | 	u64 elog_len;	/* MCA Error Log Directory length */ | 
 | 	u32 flags;	/* bit 0 - OS/VMM Opt-in */ | 
 | 	u8  rev0[12]; | 
 | 	u32 entries;	/* Valid L1 Directory entries per logical processor */ | 
 | 	u8  rev1[12]; | 
 | }; | 
 |  | 
 | static u8 extlog_dsm_uuid[] __initdata = "663E35AF-CC10-41A4-88EA-5470AF055295"; | 
 |  | 
 | /* L1 table related physical address */ | 
 | static u64 elog_base; | 
 | static size_t elog_size; | 
 | static u64 l1_dirbase; | 
 | static size_t l1_size; | 
 |  | 
 | /* L1 table related virtual address */ | 
 | static void __iomem *extlog_l1_addr; | 
 | static void __iomem *elog_addr; | 
 |  | 
 | static void *elog_buf; | 
 |  | 
 | static u64 *l1_entry_base; | 
 | static u32 l1_percpu_entry; | 
 |  | 
 | #define ELOG_IDX(cpu, bank) \ | 
 | 	(cpu_physical_id(cpu) * l1_percpu_entry + (bank)) | 
 |  | 
 | #define ELOG_ENTRY_DATA(idx) \ | 
 | 	(*(l1_entry_base + (idx))) | 
 |  | 
 | #define ELOG_ENTRY_ADDR(phyaddr) \ | 
 | 	(phyaddr - elog_base + (u8 *)elog_addr) | 
 |  | 
 | static struct acpi_hest_generic_status *extlog_elog_entry_check(int cpu, int bank) | 
 | { | 
 | 	int idx; | 
 | 	u64 data; | 
 | 	struct acpi_hest_generic_status *estatus; | 
 |  | 
 | 	WARN_ON(cpu < 0); | 
 | 	idx = ELOG_IDX(cpu, bank); | 
 | 	data = ELOG_ENTRY_DATA(idx); | 
 | 	if ((data & ELOG_ENTRY_VALID) == 0) | 
 | 		return NULL; | 
 |  | 
 | 	data &= EXT_ELOG_ENTRY_MASK; | 
 | 	estatus = (struct acpi_hest_generic_status *)ELOG_ENTRY_ADDR(data); | 
 |  | 
 | 	/* if no valid data in elog entry, just return */ | 
 | 	if (estatus->block_status == 0) | 
 | 		return NULL; | 
 |  | 
 | 	return estatus; | 
 | } | 
 |  | 
 | static void __print_extlog_rcd(const char *pfx, | 
 | 			       struct acpi_hest_generic_status *estatus, int cpu) | 
 | { | 
 | 	static atomic_t seqno; | 
 | 	unsigned int curr_seqno; | 
 | 	char pfx_seq[64]; | 
 |  | 
 | 	if (!pfx) { | 
 | 		if (estatus->error_severity <= CPER_SEV_CORRECTED) | 
 | 			pfx = KERN_INFO; | 
 | 		else | 
 | 			pfx = KERN_ERR; | 
 | 	} | 
 | 	curr_seqno = atomic_inc_return(&seqno); | 
 | 	snprintf(pfx_seq, sizeof(pfx_seq), "%s{%u}", pfx, curr_seqno); | 
 | 	printk("%s""Hardware error detected on CPU%d\n", pfx_seq, cpu); | 
 | 	cper_estatus_print(pfx_seq, estatus); | 
 | } | 
 |  | 
 | static int print_extlog_rcd(const char *pfx, | 
 | 			    struct acpi_hest_generic_status *estatus, int cpu) | 
 | { | 
 | 	/* Not more than 2 messages every 5 seconds */ | 
 | 	static DEFINE_RATELIMIT_STATE(ratelimit_corrected, 5*HZ, 2); | 
 | 	static DEFINE_RATELIMIT_STATE(ratelimit_uncorrected, 5*HZ, 2); | 
 | 	struct ratelimit_state *ratelimit; | 
 |  | 
 | 	if (estatus->error_severity == CPER_SEV_CORRECTED || | 
 | 	    (estatus->error_severity == CPER_SEV_INFORMATIONAL)) | 
 | 		ratelimit = &ratelimit_corrected; | 
 | 	else | 
 | 		ratelimit = &ratelimit_uncorrected; | 
 | 	if (__ratelimit(ratelimit)) { | 
 | 		__print_extlog_rcd(pfx, estatus, cpu); | 
 | 		return 0; | 
 | 	} | 
 |  | 
 | 	return 1; | 
 | } | 
 |  | 
 | static int extlog_print(struct notifier_block *nb, unsigned long val, | 
 | 			void *data) | 
 | { | 
 | 	struct mce *mce = (struct mce *)data; | 
 | 	int	bank = mce->bank; | 
 | 	int	cpu = mce->extcpu; | 
 | 	struct acpi_hest_generic_status *estatus, *tmp; | 
 | 	struct acpi_hest_generic_data *gdata; | 
 | 	const guid_t *fru_id = &guid_null; | 
 | 	char *fru_text = ""; | 
 | 	guid_t *sec_type; | 
 | 	static u32 err_seq; | 
 |  | 
 | 	estatus = extlog_elog_entry_check(cpu, bank); | 
 | 	if (estatus == NULL || (mce->kflags & MCE_HANDLED_CEC)) | 
 | 		return NOTIFY_DONE; | 
 |  | 
 | 	memcpy(elog_buf, (void *)estatus, ELOG_ENTRY_LEN); | 
 | 	/* clear record status to enable BIOS to update it again */ | 
 | 	estatus->block_status = 0; | 
 |  | 
 | 	tmp = (struct acpi_hest_generic_status *)elog_buf; | 
 |  | 
 | 	if (!ras_userspace_consumers()) { | 
 | 		print_extlog_rcd(NULL, tmp, cpu); | 
 | 		goto out; | 
 | 	} | 
 |  | 
 | 	/* log event via trace */ | 
 | 	err_seq++; | 
 | 	gdata = (struct acpi_hest_generic_data *)(tmp + 1); | 
 | 	if (gdata->validation_bits & CPER_SEC_VALID_FRU_ID) | 
 | 		fru_id = (guid_t *)gdata->fru_id; | 
 | 	if (gdata->validation_bits & CPER_SEC_VALID_FRU_TEXT) | 
 | 		fru_text = gdata->fru_text; | 
 | 	sec_type = (guid_t *)gdata->section_type; | 
 | 	if (guid_equal(sec_type, &CPER_SEC_PLATFORM_MEM)) { | 
 | 		struct cper_sec_mem_err *mem = (void *)(gdata + 1); | 
 | 		if (gdata->error_data_length >= sizeof(*mem)) | 
 | 			trace_extlog_mem_event(mem, err_seq, fru_id, fru_text, | 
 | 					       (u8)gdata->error_severity); | 
 | 	} | 
 |  | 
 | out: | 
 | 	mce->kflags |= MCE_HANDLED_EXTLOG; | 
 | 	return NOTIFY_OK; | 
 | } | 
 |  | 
 | static bool __init extlog_get_l1addr(void) | 
 | { | 
 | 	guid_t guid; | 
 | 	acpi_handle handle; | 
 | 	union acpi_object *obj; | 
 |  | 
 | 	if (guid_parse(extlog_dsm_uuid, &guid)) | 
 | 		return false; | 
 | 	if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &handle))) | 
 | 		return false; | 
 | 	if (!acpi_check_dsm(handle, &guid, EXTLOG_DSM_REV, 1 << EXTLOG_FN_ADDR)) | 
 | 		return false; | 
 | 	obj = acpi_evaluate_dsm_typed(handle, &guid, EXTLOG_DSM_REV, | 
 | 				      EXTLOG_FN_ADDR, NULL, ACPI_TYPE_INTEGER); | 
 | 	if (!obj) { | 
 | 		return false; | 
 | 	} else { | 
 | 		l1_dirbase = obj->integer.value; | 
 | 		ACPI_FREE(obj); | 
 | 	} | 
 |  | 
 | 	/* Spec says L1 directory must be 4K aligned, bail out if it isn't */ | 
 | 	if (l1_dirbase & ((1 << 12) - 1)) { | 
 | 		pr_warn(FW_BUG "L1 Directory is invalid at physical %llx\n", | 
 | 			l1_dirbase); | 
 | 		return false; | 
 | 	} | 
 |  | 
 | 	return true; | 
 | } | 
 | static struct notifier_block extlog_mce_dec = { | 
 | 	.notifier_call	= extlog_print, | 
 | 	.priority	= MCE_PRIO_EXTLOG, | 
 | }; | 
 |  | 
 | static int __init extlog_init(void) | 
 | { | 
 | 	struct extlog_l1_head *l1_head; | 
 | 	void __iomem *extlog_l1_hdr; | 
 | 	size_t l1_hdr_size; | 
 | 	struct resource *r; | 
 | 	u64 cap; | 
 | 	int rc; | 
 |  | 
 | 	if (rdmsrl_safe(MSR_IA32_MCG_CAP, &cap) || | 
 | 	    !(cap & MCG_ELOG_P) || | 
 | 	    !extlog_get_l1addr()) | 
 | 		return -ENODEV; | 
 |  | 
 | 	rc = -EINVAL; | 
 | 	/* get L1 header to fetch necessary information */ | 
 | 	l1_hdr_size = sizeof(struct extlog_l1_head); | 
 | 	r = request_mem_region(l1_dirbase, l1_hdr_size, "L1 DIR HDR"); | 
 | 	if (!r) { | 
 | 		pr_warn(FW_BUG EMCA_BUG, | 
 | 			(unsigned long long)l1_dirbase, | 
 | 			(unsigned long long)l1_dirbase + l1_hdr_size); | 
 | 		goto err; | 
 | 	} | 
 |  | 
 | 	extlog_l1_hdr = acpi_os_map_iomem(l1_dirbase, l1_hdr_size); | 
 | 	l1_head = (struct extlog_l1_head *)extlog_l1_hdr; | 
 | 	l1_size = l1_head->total_len; | 
 | 	l1_percpu_entry = l1_head->entries; | 
 | 	elog_base = l1_head->elog_base; | 
 | 	elog_size = l1_head->elog_len; | 
 | 	acpi_os_unmap_iomem(extlog_l1_hdr, l1_hdr_size); | 
 | 	release_mem_region(l1_dirbase, l1_hdr_size); | 
 |  | 
 | 	/* remap L1 header again based on completed information */ | 
 | 	r = request_mem_region(l1_dirbase, l1_size, "L1 Table"); | 
 | 	if (!r) { | 
 | 		pr_warn(FW_BUG EMCA_BUG, | 
 | 			(unsigned long long)l1_dirbase, | 
 | 			(unsigned long long)l1_dirbase + l1_size); | 
 | 		goto err; | 
 | 	} | 
 | 	extlog_l1_addr = acpi_os_map_iomem(l1_dirbase, l1_size); | 
 | 	l1_entry_base = (u64 *)((u8 *)extlog_l1_addr + l1_hdr_size); | 
 |  | 
 | 	/* remap elog table */ | 
 | 	r = request_mem_region(elog_base, elog_size, "Elog Table"); | 
 | 	if (!r) { | 
 | 		pr_warn(FW_BUG EMCA_BUG, | 
 | 			(unsigned long long)elog_base, | 
 | 			(unsigned long long)elog_base + elog_size); | 
 | 		goto err_release_l1_dir; | 
 | 	} | 
 | 	elog_addr = acpi_os_map_iomem(elog_base, elog_size); | 
 |  | 
 | 	rc = -ENOMEM; | 
 | 	/* allocate buffer to save elog record */ | 
 | 	elog_buf = kmalloc(ELOG_ENTRY_LEN, GFP_KERNEL); | 
 | 	if (elog_buf == NULL) | 
 | 		goto err_release_elog; | 
 |  | 
 | 	mce_register_decode_chain(&extlog_mce_dec); | 
 | 	/* enable OS to be involved to take over management from BIOS */ | 
 | 	((struct extlog_l1_head *)extlog_l1_addr)->flags |= FLAG_OS_OPTIN; | 
 |  | 
 | 	return 0; | 
 |  | 
 | err_release_elog: | 
 | 	if (elog_addr) | 
 | 		acpi_os_unmap_iomem(elog_addr, elog_size); | 
 | 	release_mem_region(elog_base, elog_size); | 
 | err_release_l1_dir: | 
 | 	if (extlog_l1_addr) | 
 | 		acpi_os_unmap_iomem(extlog_l1_addr, l1_size); | 
 | 	release_mem_region(l1_dirbase, l1_size); | 
 | err: | 
 | 	pr_warn(FW_BUG "Extended error log disabled because of problems parsing f/w tables\n"); | 
 | 	return rc; | 
 | } | 
 |  | 
 | static void __exit extlog_exit(void) | 
 | { | 
 | 	mce_unregister_decode_chain(&extlog_mce_dec); | 
 | 	((struct extlog_l1_head *)extlog_l1_addr)->flags &= ~FLAG_OS_OPTIN; | 
 | 	if (extlog_l1_addr) | 
 | 		acpi_os_unmap_iomem(extlog_l1_addr, l1_size); | 
 | 	if (elog_addr) | 
 | 		acpi_os_unmap_iomem(elog_addr, elog_size); | 
 | 	release_mem_region(elog_base, elog_size); | 
 | 	release_mem_region(l1_dirbase, l1_size); | 
 | 	kfree(elog_buf); | 
 | } | 
 |  | 
 | module_init(extlog_init); | 
 | module_exit(extlog_exit); | 
 |  | 
 | MODULE_AUTHOR("Chen, Gong <gong.chen@intel.com>"); | 
 | MODULE_DESCRIPTION("Extended MCA Error Log Driver"); | 
 | MODULE_LICENSE("GPL"); |