--- /dev/null
+/*
+ * APEI Generic Hardware Error Source support
+ *
+ * Generic Hardware Error Source provides a way to report platform
+ * hardware errors (such as that from chipset). It works in so called
+ * "Firmware First" mode, that is, hardware errors are reported to
+ * firmware firstly, then reported to Linux by firmware. This way,
+ * some non-standard hardware error registers or non-standard hardware
+ * link can be checked by firmware to produce more hardware error
+ * information for Linux.
+ *
+ * For more information about Generic Hardware Error Source, please
+ * refer to ACPI Specification version 4.0, section 17.3.2.6
+ *
+ * Now, only SCI notification type and memory errors are
+ * supported. More notification type and hardware error type will be
+ * added later.
+ *
+ * Copyright 2010 Intel Corp.
+ * Author: Huang Ying <ying.huang@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 as published by the Free Software Foundation;
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/acpi.h>
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/cper.h>
+#include <linux/kdebug.h>
+#include <acpi/apei.h>
+#include <acpi/atomicio.h>
+#include <acpi/hed.h>
+#include <asm/mce.h>
+
+#include "apei-internal.h"
+
+#define GHES_PFX "GHES: "
+
+#define GHES_ESTATUS_MAX_SIZE 65536
+
+/*
+ * One struct ghes is created for each generic hardware error
+ * source.
+ *
+ * It provides the context for APEI hardware error timer/IRQ/SCI/NMI
+ * handler. Handler for one generic hardware error source is only
+ * triggered after the previous one is done. So handler can uses
+ * struct ghes without locking.
+ *
+ * estatus: memory buffer for error status block, allocated during
+ * HEST parsing.
+ */
+#define GHES_TO_CLEAR 0x0001
+
+struct ghes {
+ struct acpi_hest_generic *generic;
+ struct acpi_hest_generic_status *estatus;
+ struct list_head list;
+ u64 buffer_paddr;
+ unsigned long flags;
+};
+
+/*
+ * Error source lists, one list for each notification method. The
+ * members in lists are struct ghes.
+ *
+ * The list members are only added in HEST parsing and deleted during
+ * module_exit, that is, single-threaded. So no lock is needed for
+ * that.
+ *
+ * But the mutual exclusion is needed between members adding/deleting
+ * and timer/IRQ/SCI/NMI handler, which may traverse the list. RCU is
+ * used for that.
+ */
+static LIST_HEAD(ghes_sci);
+
+static struct ghes *ghes_new(struct acpi_hest_generic *generic)
+{
+ struct ghes *ghes;
+ unsigned int error_block_length;
+ int rc;
+
+ ghes = kzalloc(sizeof(*ghes), GFP_KERNEL);
+ if (!ghes)
+ return ERR_PTR(-ENOMEM);
+ ghes->generic = generic;
+ INIT_LIST_HEAD(&ghes->list);
+ rc = acpi_pre_map_gar(&generic->error_status_address);
+ if (rc)
+ goto err_free;
+ error_block_length = generic->error_block_length;
+ if (error_block_length > GHES_ESTATUS_MAX_SIZE) {
+ pr_warning(FW_WARN GHES_PFX
+ "Error status block length is too long: %u for "
+ "generic hardware error source: %d.\n",
+ error_block_length, generic->header.source_id);
+ error_block_length = GHES_ESTATUS_MAX_SIZE;
+ }
+ ghes->estatus = kmalloc(error_block_length, GFP_KERNEL);
+ if (!ghes->estatus) {
+ rc = -ENOMEM;
+ goto err_unmap;
+ }
+
+ return ghes;
+
+err_unmap:
+ acpi_post_unmap_gar(&generic->error_status_address);
+err_free:
+ kfree(ghes);
+ return ERR_PTR(rc);
+}
+
+static void ghes_fini(struct ghes *ghes)
+{
+ kfree(ghes->estatus);
+ acpi_post_unmap_gar(&ghes->generic->error_status_address);
+}
+
+enum {
+ GHES_SER_NO = 0x0,
+ GHES_SER_CORRECTED = 0x1,
+ GHES_SER_RECOVERABLE = 0x2,
+ GHES_SER_PANIC = 0x3,
+};
+
+static inline int ghes_severity(int severity)
+{
+ switch (severity) {
+ case CPER_SER_INFORMATIONAL:
+ return GHES_SER_NO;
+ case CPER_SER_CORRECTED:
+ return GHES_SER_CORRECTED;
+ case CPER_SER_RECOVERABLE:
+ return GHES_SER_RECOVERABLE;
+ case CPER_SER_FATAL:
+ return GHES_SER_PANIC;
+ default:
+ /* Unkown, go panic */
+ return GHES_SER_PANIC;
+ }
+}
+
+/* SCI handler run in work queue, so ioremap can be used here */
+static int ghes_copy_tofrom_phys(void *buffer, u64 paddr, u32 len,
+ int from_phys)
+{
+ void *vaddr;
+
+ vaddr = ioremap_cache(paddr, len);
+ if (!vaddr)
+ return -ENOMEM;
+ if (from_phys)
+ memcpy(buffer, vaddr, len);
+ else
+ memcpy(vaddr, buffer, len);
+ iounmap(vaddr);
+
+ return 0;
+}
+
+static int ghes_read_estatus(struct ghes *ghes, int silent)
+{
+ struct acpi_hest_generic *g = ghes->generic;
+ u64 buf_paddr;
+ u32 len;
+ int rc;
+
+ rc = acpi_atomic_read(&buf_paddr, &g->error_status_address);
+ if (rc) {
+ if (!silent && printk_ratelimit())
+ pr_warning(FW_WARN GHES_PFX
+"Failed to read error status block address for hardware error source: %d.\n",
+ g->header.source_id);
+ return -EIO;
+ }
+ if (!buf_paddr)
+ return -ENOENT;
+
+ rc = ghes_copy_tofrom_phys(ghes->estatus, buf_paddr,
+ sizeof(*ghes->estatus), 1);
+ if (rc)
+ return rc;
+ if (!ghes->estatus->block_status)
+ return -ENOENT;
+
+ ghes->buffer_paddr = buf_paddr;
+ ghes->flags |= GHES_TO_CLEAR;
+
+ rc = -EIO;
+ len = apei_estatus_len(ghes->estatus);
+ if (len < sizeof(*ghes->estatus))
+ goto err_read_block;
+ if (len > ghes->generic->error_block_length)
+ goto err_read_block;
+ if (apei_estatus_check_header(ghes->estatus))
+ goto err_read_block;
+ rc = ghes_copy_tofrom_phys(ghes->estatus + 1,
+ buf_paddr + sizeof(*ghes->estatus),
+ len - sizeof(*ghes->estatus), 1);
+ if (rc)
+ return rc;
+ if (apei_estatus_check(ghes->estatus))
+ goto err_read_block;
+ rc = 0;
+
+err_read_block:
+ if (rc && !silent)
+ pr_warning(FW_WARN GHES_PFX
+ "Failed to read error status block!\n");
+ return rc;
+}
+
+static void ghes_clear_estatus(struct ghes *ghes)
+{
+ ghes->estatus->block_status = 0;
+ if (!(ghes->flags & GHES_TO_CLEAR))
+ return;
+ ghes_copy_tofrom_phys(ghes->estatus, ghes->buffer_paddr,
+ sizeof(ghes->estatus->block_status), 0);
+ ghes->flags &= ~GHES_TO_CLEAR;
+}
+
+static void ghes_do_proc(struct ghes *ghes)
+{
+ int ser, processed = 0;
+ struct acpi_hest_generic_data *gdata;
+
+ ser = ghes_severity(ghes->estatus->error_severity);
+ apei_estatus_for_each_section(ghes->estatus, gdata) {
+#ifdef CONFIG_X86_MCE
+ if (!uuid_le_cmp(*(uuid_le *)gdata->section_type,
+ CPER_SEC_PLATFORM_MEM)) {
+ apei_mce_report_mem_error(
+ ser == GHES_SER_CORRECTED,
+ (struct cper_sec_mem_err *)(gdata+1));
+ processed = 1;
+ }
+#endif
+ }
+
+ if (!processed && printk_ratelimit())
+ pr_warning(GHES_PFX
+ "Unknown error record from generic hardware error source: %d\n",
+ ghes->generic->header.source_id);
+}
+
+static int ghes_proc(struct ghes *ghes)
+{
+ int rc;
+
+ rc = ghes_read_estatus(ghes, 0);
+ if (rc)
+ goto out;
+ ghes_do_proc(ghes);
+
+out:
+ ghes_clear_estatus(ghes);
+ return 0;
+}
+
+static int ghes_notify_sci(struct notifier_block *this,
+ unsigned long event, void *data)
+{
+ struct ghes *ghes;
+ int ret = NOTIFY_DONE;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(ghes, &ghes_sci, list) {
+ if (!ghes_proc(ghes))
+ ret = NOTIFY_OK;
+ }
+ rcu_read_unlock();
+
+ return ret;
+}
+
+static struct notifier_block ghes_notifier_sci = {
+ .notifier_call = ghes_notify_sci,
+};
+
+static int hest_ghes_parse(struct acpi_hest_header *hest_hdr, void *data)
+{
+ struct acpi_hest_generic *generic;
+ struct ghes *ghes = NULL;
+ int rc = 0;
+
+ if (hest_hdr->type != ACPI_HEST_TYPE_GENERIC_ERROR)
+ return 0;
+
+ generic = (struct acpi_hest_generic *)hest_hdr;
+ if (!generic->enabled)
+ return 0;
+
+ if (generic->error_block_length <
+ sizeof(struct acpi_hest_generic_status)) {
+ pr_warning(FW_BUG GHES_PFX
+"Invalid error block length: %u for generic hardware error source: %d\n",
+ generic->error_block_length,
+ generic->header.source_id);
+ goto err;
+ }
+ if (generic->records_to_preallocate == 0) {
+ pr_warning(FW_BUG GHES_PFX
+"Invalid records to preallocate: %u for generic hardware error source: %d\n",
+ generic->records_to_preallocate,
+ generic->header.source_id);
+ goto err;
+ }
+ ghes = ghes_new(generic);
+ if (IS_ERR(ghes)) {
+ rc = PTR_ERR(ghes);
+ ghes = NULL;
+ goto err;
+ }
+ switch (generic->notify.type) {
+ case ACPI_HEST_NOTIFY_POLLED:
+ pr_warning(GHES_PFX
+"Generic hardware error source: %d notified via POLL is not supported!\n",
+ generic->header.source_id);
+ break;
+ case ACPI_HEST_NOTIFY_EXTERNAL:
+ case ACPI_HEST_NOTIFY_LOCAL:
+ pr_warning(GHES_PFX
+"Generic hardware error source: %d notified via IRQ is not supported!\n",
+ generic->header.source_id);
+ break;
+ case ACPI_HEST_NOTIFY_SCI:
+ if (list_empty(&ghes_sci))
+ register_acpi_hed_notifier(&ghes_notifier_sci);
+ list_add_rcu(&ghes->list, &ghes_sci);
+ break;
+ case ACPI_HEST_NOTIFY_NMI:
+ pr_warning(GHES_PFX
+"Generic hardware error source: %d notified via NMI is not supported!\n",
+ generic->header.source_id);
+ break;
+ default:
+ pr_warning(FW_WARN GHES_PFX
+ "Unknown notification type: %u for generic hardware error source: %d\n",
+ generic->notify.type, generic->header.source_id);
+ break;
+ }
+
+ return 0;
+err:
+ if (ghes)
+ ghes_fini(ghes);
+ return rc;
+}
+
+static void ghes_cleanup(void)
+{
+ struct ghes *ghes, *nghes;
+
+ if (!list_empty(&ghes_sci))
+ unregister_acpi_hed_notifier(&ghes_notifier_sci);
+
+ synchronize_rcu();
+
+ list_for_each_entry_safe(ghes, nghes, &ghes_sci, list) {
+ list_del(&ghes->list);
+ ghes_fini(ghes);
+ kfree(ghes);
+ }
+}
+
+static int __init ghes_init(void)
+{
+ int rc;
+
+ if (acpi_disabled)
+ return -ENODEV;
+
+ if (hest_disable) {
+ pr_info(GHES_PFX "HEST is not enabled!\n");
+ return -EINVAL;
+ }
+
+ rc = apei_hest_parse(hest_ghes_parse, NULL);
+ if (rc) {
+ pr_err(GHES_PFX
+ "Error during parsing HEST generic hardware error sources.\n");
+ goto err_cleanup;
+ }
+
+ if (list_empty(&ghes_sci)) {
+ pr_info(GHES_PFX
+ "No functional generic hardware error sources.\n");
+ rc = -ENODEV;
+ goto err_cleanup;
+ }
+
+ pr_info(GHES_PFX
+ "Generic Hardware Error Source support is initialized.\n");
+
+ return 0;
+err_cleanup:
+ ghes_cleanup();
+ return rc;
+}
+
+static void __exit ghes_exit(void)
+{
+ ghes_cleanup();
+}
+
+module_init(ghes_init);
+module_exit(ghes_exit);
+
+MODULE_AUTHOR("Huang Ying");
+MODULE_DESCRIPTION("APEI Generic Hardware Error Source support");
+MODULE_LICENSE("GPL");
projects / GitHub / exynos8895 / android_kernel_samsung_universal8895.git / commitdiff