[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / acpi / apei / ghes.c

/*
 * 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
 *
 * 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/timer.h>
#include <linux/cper.h>
#include <linux/kdebug.h>
#include <linux/platform_device.h>
#include <linux/mutex.h>
#include <linux/ratelimit.h>
#include <linux/vmalloc.h>
#include <acpi/apei.h>
#include <acpi/atomicio.h>
#include <acpi/hed.h>
#include <asm/mce.h>
#include <asm/tlbflush.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.
 *
 * estatus: memory buffer for error status block, allocated during
 * HEST parsing.
 */
#define GHES_TO_CLEAR		0x0001
#define GHES_EXITING		0x0002

struct ghes {
	struct acpi_hest_generic *generic;
	struct acpi_hest_generic_status *estatus;
	u64 buffer_paddr;
	unsigned long flags;
	union {
		struct list_head list;
		struct timer_list timer;
		unsigned int irq;
	};
};

static int ghes_panic_timeout	__read_mostly = 30;

/*
 * All error sources notified with SCI shares one notifier function,
 * so they need to be linked and checked one by one.  This is applied
 * to NMI too.
 *
 * RCU is used for these lists, so ghes_list_mutex is only used for
 * list changing, not for traversing.
 */
static LIST_HEAD(ghes_sci);
static LIST_HEAD(ghes_nmi);
static DEFINE_MUTEX(ghes_list_mutex);

/*
 * NMI may be triggered on any CPU, so ghes_nmi_lock is used for
 * mutual exclusion.
 */
static DEFINE_RAW_SPINLOCK(ghes_nmi_lock);

/*
 * Because the memory area used to transfer hardware error information
 * from BIOS to Linux can be determined only in NMI, IRQ or timer
 * handler, but general ioremap can not be used in atomic context, so
 * a special version of atomic ioremap is implemented for that.
 */

/*
 * Two virtual pages are used, one for NMI context, the other for
 * IRQ/PROCESS context
 */
#define GHES_IOREMAP_PAGES		2
#define GHES_IOREMAP_NMI_PAGE(base)	(base)
#define GHES_IOREMAP_IRQ_PAGE(base)	((base) + PAGE_SIZE)

/* virtual memory area for atomic ioremap */
static struct vm_struct *ghes_ioremap_area;
/*
 * These 2 spinlock is used to prevent atomic ioremap virtual memory
 * area from being mapped simultaneously.
 */
static DEFINE_RAW_SPINLOCK(ghes_ioremap_lock_nmi);
static DEFINE_SPINLOCK(ghes_ioremap_lock_irq);

static int ghes_ioremap_init(void)
{
	ghes_ioremap_area = __get_vm_area(PAGE_SIZE * GHES_IOREMAP_PAGES,
		VM_IOREMAP, VMALLOC_START, VMALLOC_END);
	if (!ghes_ioremap_area) {
		pr_err(GHES_PFX "Failed to allocate virtual memory area for atomic ioremap.\n");
		return -ENOMEM;
	}

	return 0;
}

static void ghes_ioremap_exit(void)
{
	free_vm_area(ghes_ioremap_area);
}

static void __iomem *ghes_ioremap_pfn_nmi(u64 pfn)
{
	unsigned long vaddr;

	vaddr = (unsigned long)GHES_IOREMAP_NMI_PAGE(ghes_ioremap_area->addr);
	ioremap_page_range(vaddr, vaddr + PAGE_SIZE,
			   pfn << PAGE_SHIFT, PAGE_KERNEL);

	return (void __iomem *)vaddr;
}

static void __iomem *ghes_ioremap_pfn_irq(u64 pfn)
{
	unsigned long vaddr;

	vaddr = (unsigned long)GHES_IOREMAP_IRQ_PAGE(ghes_ioremap_area->addr);
	ioremap_page_range(vaddr, vaddr + PAGE_SIZE,
			   pfn << PAGE_SHIFT, PAGE_KERNEL);

	return (void __iomem *)vaddr;
}

static void ghes_iounmap_nmi(void __iomem *vaddr_ptr)
{
	unsigned long vaddr = (unsigned long __force)vaddr_ptr;
	void *base = ghes_ioremap_area->addr;

	BUG_ON(vaddr != (unsigned long)GHES_IOREMAP_NMI_PAGE(base));
	unmap_kernel_range_noflush(vaddr, PAGE_SIZE);
	__flush_tlb_one(vaddr);
}

static void ghes_iounmap_irq(void __iomem *vaddr_ptr)
{
	unsigned long vaddr = (unsigned long __force)vaddr_ptr;
	void *base = ghes_ioremap_area->addr;

	BUG_ON(vaddr != (unsigned long)GHES_IOREMAP_IRQ_PAGE(base));
	unmap_kernel_range_noflush(vaddr, PAGE_SIZE);
	__flush_tlb_one(vaddr);
}

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;
	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_SEV_NO = 0x0,
	GHES_SEV_CORRECTED = 0x1,
	GHES_SEV_RECOVERABLE = 0x2,
	GHES_SEV_PANIC = 0x3,
};

static inline int ghes_severity(int severity)
{
	switch (severity) {
	case CPER_SEV_INFORMATIONAL:
		return GHES_SEV_NO;
	case CPER_SEV_CORRECTED:
		return GHES_SEV_CORRECTED;
	case CPER_SEV_RECOVERABLE:
		return GHES_SEV_RECOVERABLE;
	case CPER_SEV_FATAL:
		return GHES_SEV_PANIC;
	default:
		/* Unknown, go panic */
		return GHES_SEV_PANIC;
	}
}

static void ghes_copy_tofrom_phys(void *buffer, u64 paddr, u32 len,
				  int from_phys)
{
	void __iomem *vaddr;
	unsigned long flags = 0;
	int in_nmi = in_nmi();
	u64 offset;
	u32 trunk;

	while (len > 0) {
		offset = paddr - (paddr & PAGE_MASK);
		if (in_nmi) {
			raw_spin_lock(&ghes_ioremap_lock_nmi);
			vaddr = ghes_ioremap_pfn_nmi(paddr >> PAGE_SHIFT);
		} else {
			spin_lock_irqsave(&ghes_ioremap_lock_irq, flags);
			vaddr = ghes_ioremap_pfn_irq(paddr >> PAGE_SHIFT);
		}
		trunk = PAGE_SIZE - offset;
		trunk = min(trunk, len);
		if (from_phys)
			memcpy_fromio(buffer, vaddr + offset, trunk);
		else
			memcpy_toio(vaddr + offset, buffer, trunk);
		len -= trunk;
		paddr += trunk;
		buffer += trunk;
		if (in_nmi) {
			ghes_iounmap_nmi(vaddr);
			raw_spin_unlock(&ghes_ioremap_lock_nmi);
		} else {
			ghes_iounmap_irq(vaddr);
			spin_unlock_irqrestore(&ghes_ioremap_lock_irq, flags);
		}
	}
}

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;

	ghes_copy_tofrom_phys(ghes->estatus, buf_paddr,
			      sizeof(*ghes->estatus), 1);
	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;
	ghes_copy_tofrom_phys(ghes->estatus + 1,
			      buf_paddr + sizeof(*ghes->estatus),
			      len - sizeof(*ghes->estatus), 1);
	if (apei_estatus_check(ghes->estatus))
		goto err_read_block;
	rc = 0;

err_read_block:
	if (rc && !silent && printk_ratelimit())
		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 sev, processed = 0;
	struct acpi_hest_generic_data *gdata;

	sev = 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(
				sev == GHES_SEV_CORRECTED,
				(struct cper_sec_mem_err *)(gdata+1));
			processed = 1;
		}
#endif
	}
}

static void ghes_print_estatus(const char *pfx, struct ghes *ghes)
{
	/* Not more than 2 messages every 5 seconds */
	static DEFINE_RATELIMIT_STATE(ratelimit, 5*HZ, 2);

	if (pfx == NULL) {
		if (ghes_severity(ghes->estatus->error_severity) <=
		    GHES_SEV_CORRECTED)
			pfx = KERN_WARNING HW_ERR;
		else
			pfx = KERN_ERR HW_ERR;
	}
	if (__ratelimit(&ratelimit)) {
		printk(
	"%s""Hardware error from APEI Generic Hardware Error Source: %d\n",
	pfx, ghes->generic->header.source_id);
		apei_estatus_print(pfx, ghes->estatus);
	}
}

static int ghes_proc(struct ghes *ghes)
{
	int rc;

	rc = ghes_read_estatus(ghes, 0);
	if (rc)
		goto out;
	ghes_print_estatus(NULL, ghes);
	ghes_do_proc(ghes);

out:
	ghes_clear_estatus(ghes);
	return 0;
}

static void ghes_add_timer(struct ghes *ghes)
{
	struct acpi_hest_generic *g = ghes->generic;
	unsigned long expire;

	if (!g->notify.poll_interval) {
		pr_warning(FW_WARN GHES_PFX "Poll interval is 0 for generic hardware error source: %d, disabled.\n",
			   g->header.source_id);
		return;
	}
	expire = jiffies + msecs_to_jiffies(g->notify.poll_interval);
	ghes->timer.expires = round_jiffies_relative(expire);
	add_timer(&ghes->timer);
}

static void ghes_poll_func(unsigned long data)
{
	struct ghes *ghes = (void *)data;

	ghes_proc(ghes);
	if (!(ghes->flags & GHES_EXITING))
		ghes_add_timer(ghes);
}

static irqreturn_t ghes_irq_func(int irq, void *data)
{
	struct ghes *ghes = data;
	int rc;

	rc = ghes_proc(ghes);
	if (rc)
		return IRQ_NONE;

	return IRQ_HANDLED;
}

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 int ghes_notify_nmi(struct notifier_block *this,
				  unsigned long cmd, void *data)
{
	struct ghes *ghes, *ghes_global = NULL;
	int sev, sev_global = -1;
	int ret = NOTIFY_DONE;

	if (cmd != DIE_NMI)
		return ret;

	raw_spin_lock(&ghes_nmi_lock);
	list_for_each_entry_rcu(ghes, &ghes_nmi, list) {
		if (ghes_read_estatus(ghes, 1)) {
			ghes_clear_estatus(ghes);
			continue;
		}
		sev = ghes_severity(ghes->estatus->error_severity);
		if (sev > sev_global) {
			sev_global = sev;
			ghes_global = ghes;
		}
		ret = NOTIFY_STOP;
	}

	if (ret == NOTIFY_DONE)
		goto out;

	if (sev_global >= GHES_SEV_PANIC) {
		oops_begin();
		ghes_print_estatus(KERN_EMERG HW_ERR, ghes_global);
		/* reboot to log the error! */
		if (panic_timeout == 0)
			panic_timeout = ghes_panic_timeout;
		panic("Fatal hardware error!");
	}

	list_for_each_entry_rcu(ghes, &ghes_nmi, list) {
		if (!(ghes->flags & GHES_TO_CLEAR))
			continue;
		/* Do not print estatus because printk is not NMI safe */
		ghes_do_proc(ghes);
		ghes_clear_estatus(ghes);
	}

out:
	raw_spin_unlock(&ghes_nmi_lock);
	return ret;
}

static struct notifier_block ghes_notifier_sci = {
	.notifier_call = ghes_notify_sci,
};

static struct notifier_block ghes_notifier_nmi = {
	.notifier_call = ghes_notify_nmi,
};

static int __devinit ghes_probe(struct platform_device *ghes_dev)
{
	struct acpi_hest_generic *generic;
	struct ghes *ghes = NULL;
	int rc = -EINVAL;

	generic = *(struct acpi_hest_generic **)ghes_dev->dev.platform_data;
	if (!generic->enabled)
		return -ENODEV;

	switch (generic->notify.type) {
	case ACPI_HEST_NOTIFY_POLLED:
	case ACPI_HEST_NOTIFY_EXTERNAL:
	case ACPI_HEST_NOTIFY_SCI:
	case ACPI_HEST_NOTIFY_NMI:
		break;
	case ACPI_HEST_NOTIFY_LOCAL:
		pr_warning(GHES_PFX "Generic hardware error source: %d notified via local interrupt is not supported!\n",
			   generic->header.source_id);
		goto err;
	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);
		goto err;
	}

	rc = -EIO;
	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;
	}
	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:
		ghes->timer.function = ghes_poll_func;
		ghes->timer.data = (unsigned long)ghes;
		init_timer_deferrable(&ghes->timer);
		ghes_add_timer(ghes);
		break;
	case ACPI_HEST_NOTIFY_EXTERNAL:
		/* External interrupt vector is GSI */
		if (acpi_gsi_to_irq(generic->notify.vector, &ghes->irq)) {
			pr_err(GHES_PFX "Failed to map GSI to IRQ for generic hardware error source: %d\n",
			       generic->header.source_id);
			goto err;
		}
		if (request_irq(ghes->irq, ghes_irq_func,
				0, "GHES IRQ", ghes)) {
			pr_err(GHES_PFX "Failed to register IRQ for generic hardware error source: %d\n",
			       generic->header.source_id);
			goto err;
		}
		break;
	case ACPI_HEST_NOTIFY_SCI:
		mutex_lock(&ghes_list_mutex);
		if (list_empty(&ghes_sci))
			register_acpi_hed_notifier(&ghes_notifier_sci);
		list_add_rcu(&ghes->list, &ghes_sci);
		mutex_unlock(&ghes_list_mutex);
		break;
	case ACPI_HEST_NOTIFY_NMI:
		mutex_lock(&ghes_list_mutex);
		if (list_empty(&ghes_nmi))
			register_die_notifier(&ghes_notifier_nmi);
		list_add_rcu(&ghes->list, &ghes_nmi);
		mutex_unlock(&ghes_list_mutex);
		break;
	default:
		BUG();
	}
	platform_set_drvdata(ghes_dev, ghes);

	return 0;
err:
	if (ghes) {
		ghes_fini(ghes);
		kfree(ghes);
	}
	return rc;
}

static int __devexit ghes_remove(struct platform_device *ghes_dev)
{
	struct ghes *ghes;
	struct acpi_hest_generic *generic;

	ghes = platform_get_drvdata(ghes_dev);
	generic = ghes->generic;

	ghes->flags |= GHES_EXITING;
	switch (generic->notify.type) {
	case ACPI_HEST_NOTIFY_POLLED:
		del_timer_sync(&ghes->timer);
		break;
	case ACPI_HEST_NOTIFY_EXTERNAL:
		free_irq(ghes->irq, ghes);
		break;
	case ACPI_HEST_NOTIFY_SCI:
		mutex_lock(&ghes_list_mutex);
		list_del_rcu(&ghes->list);
		if (list_empty(&ghes_sci))
			unregister_acpi_hed_notifier(&ghes_notifier_sci);
		mutex_unlock(&ghes_list_mutex);
		break;
	case ACPI_HEST_NOTIFY_NMI:
		mutex_lock(&ghes_list_mutex);
		list_del_rcu(&ghes->list);
		if (list_empty(&ghes_nmi))
			unregister_die_notifier(&ghes_notifier_nmi);
		mutex_unlock(&ghes_list_mutex);
		/*
		 * To synchronize with NMI handler, ghes can only be
		 * freed after NMI handler finishes.
		 */
		synchronize_rcu();
		break;
	default:
		BUG();
		break;
	}

	ghes_fini(ghes);
	kfree(ghes);

	platform_set_drvdata(ghes_dev, NULL);

	return 0;
}

static struct platform_driver ghes_platform_driver = {
	.driver		= {
		.name	= "GHES",
		.owner	= THIS_MODULE,
	},
	.probe		= ghes_probe,
	.remove		= ghes_remove,
};

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 = ghes_ioremap_init();
	if (rc)
		goto err;

	rc = platform_driver_register(&ghes_platform_driver);
	if (rc)
		goto err_ioremap_exit;

	return 0;
err_ioremap_exit:
	ghes_ioremap_exit();
err:
	return rc;
}

static void __exit ghes_exit(void)
{
	platform_driver_unregister(&ghes_platform_driver);
	ghes_ioremap_exit();
}

module_init(ghes_init);
module_exit(ghes_exit);

MODULE_AUTHOR("Huang Ying");
MODULE_DESCRIPTION("APEI Generic Hardware Error Source support");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:GHES");
Commit	Line	Data
d334a491 HY	1	/*
	2	* APEI Generic Hardware Error Source support
	3	*
	4	* Generic Hardware Error Source provides a way to report platform
	5	* hardware errors (such as that from chipset). It works in so called
	6	* "Firmware First" mode, that is, hardware errors are reported to
	7	* firmware firstly, then reported to Linux by firmware. This way,
	8	* some non-standard hardware error registers or non-standard hardware
	9	* link can be checked by firmware to produce more hardware error
	10	* information for Linux.
	11	*
	12	* For more information about Generic Hardware Error Source, please
	13	* refer to ACPI Specification version 4.0, section 17.3.2.6
	14	*
d334a491 HY	15	* Copyright 2010 Intel Corp.
	16	* Author: Huang Ying <ying.huang@intel.com>
	17	*
	18	* This program is free software; you can redistribute it and/or
	19	* modify it under the terms of the GNU General Public License version
	20	* 2 as published by the Free Software Foundation;
	21	*
	22	* This program is distributed in the hope that it will be useful,
	23	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	24	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	25	* GNU General Public License for more details.
	26	*
	27	* You should have received a copy of the GNU General Public License
	28	* along with this program; if not, write to the Free Software
	29	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	30	*/
	31
	32	#include <linux/kernel.h>
	33	#include <linux/module.h>
	34	#include <linux/init.h>
	35	#include <linux/acpi.h>
	36	#include <linux/io.h>
	37	#include <linux/interrupt.h>
81e88fdc	38	#include <linux/timer.h>
d334a491 HY	39	#include <linux/cper.h>
d334a491 HY	40	#include <linux/kdebug.h>
7ad6e943 HY	41	#include <linux/platform_device.h>
7ad6e943 HY	42	#include <linux/mutex.h>
32c361f5	43	#include <linux/ratelimit.h>
81e88fdc	44	#include <linux/vmalloc.h>
d334a491 HY	45	#include <acpi/apei.h>
	46	#include <acpi/atomicio.h>
	47	#include <acpi/hed.h>
	48	#include <asm/mce.h>
81e88fdc	49	#include <asm/tlbflush.h>
d334a491 HY	50
	51	#include "apei-internal.h"
	52
	53	#define GHES_PFX "GHES: "
	54
	55	#define GHES_ESTATUS_MAX_SIZE 65536
	56
	57	/*
81e88fdc	58	* One struct ghes is created for each generic hardware error source.
d334a491	59	* It provides the context for APEI hardware error timer/IRQ/SCI/NMI
81e88fdc	60	* handler.
d334a491 HY	61	*
	62	* estatus: memory buffer for error status block, allocated during
	63	* HEST parsing.
	64	*/
	65	#define GHES_TO_CLEAR 0x0001
81e88fdc	66	#define GHES_EXITING 0x0002
d334a491 HY	67
	68	struct ghes {
	69	struct acpi_hest_generic *generic;
	70	struct acpi_hest_generic_status *estatus;
d334a491 HY	71	u64 buffer_paddr;
d334a491 HY	72	unsigned long flags;
81e88fdc HY	73	union {
	74	struct list_head list;
	75	struct timer_list timer;
	76	unsigned int irq;
	77	};
d334a491 HY	78	};
d334a491 HY	79
81e88fdc HY	80	static int ghes_panic_timeout __read_mostly = 30;
81e88fdc HY	81
d334a491	82	/*
81e88fdc HY	83	* All error sources notified with SCI shares one notifier function,
	84	* so they need to be linked and checked one by one. This is applied
	85	* to NMI too.
d334a491	86	*
81e88fdc HY	87	* RCU is used for these lists, so ghes_list_mutex is only used for
81e88fdc HY	88	* list changing, not for traversing.
d334a491 HY	89	*/
d334a491 HY	90	static LIST_HEAD(ghes_sci);
81e88fdc	91	static LIST_HEAD(ghes_nmi);
7ad6e943	92	static DEFINE_MUTEX(ghes_list_mutex);
d334a491	93
81e88fdc HY	94	/*
	95	* NMI may be triggered on any CPU, so ghes_nmi_lock is used for
	96	* mutual exclusion.
	97	*/
	98	static DEFINE_RAW_SPINLOCK(ghes_nmi_lock);
	99
	100	/*
	101	* Because the memory area used to transfer hardware error information
	102	* from BIOS to Linux can be determined only in NMI, IRQ or timer
	103	* handler, but general ioremap can not be used in atomic context, so
	104	* a special version of atomic ioremap is implemented for that.
	105	*/
	106
	107	/*
	108	* Two virtual pages are used, one for NMI context, the other for
	109	* IRQ/PROCESS context
	110	*/
	111	#define GHES_IOREMAP_PAGES 2
	112	#define GHES_IOREMAP_NMI_PAGE(base) (base)
	113	#define GHES_IOREMAP_IRQ_PAGE(base) ((base) + PAGE_SIZE)
	114
	115	/* virtual memory area for atomic ioremap */
	116	static struct vm_struct *ghes_ioremap_area;
	117	/*
	118	* These 2 spinlock is used to prevent atomic ioremap virtual memory
	119	* area from being mapped simultaneously.
	120	*/
	121	static DEFINE_RAW_SPINLOCK(ghes_ioremap_lock_nmi);
	122	static DEFINE_SPINLOCK(ghes_ioremap_lock_irq);
	123
	124	static int ghes_ioremap_init(void)
	125	{
	126	ghes_ioremap_area = __get_vm_area(PAGE_SIZE * GHES_IOREMAP_PAGES,
	127	VM_IOREMAP, VMALLOC_START, VMALLOC_END);
	128	if (!ghes_ioremap_area) {
	129	pr_err(GHES_PFX "Failed to allocate virtual memory area for atomic ioremap.\n");
	130	return -ENOMEM;
	131	}
	132
	133	return 0;
	134	}
	135
	136	static void ghes_ioremap_exit(void)
	137	{
	138	free_vm_area(ghes_ioremap_area);
	139	}
	140
	141	static void __iomem *ghes_ioremap_pfn_nmi(u64 pfn)
	142	{
	143	unsigned long vaddr;
	144
	145	vaddr = (unsigned long)GHES_IOREMAP_NMI_PAGE(ghes_ioremap_area->addr);
	146	ioremap_page_range(vaddr, vaddr + PAGE_SIZE,
	147	pfn << PAGE_SHIFT, PAGE_KERNEL);
	148
	149	return (void __iomem *)vaddr;
	150	}
	151
	152	static void __iomem *ghes_ioremap_pfn_irq(u64 pfn)
	153	{
	154	unsigned long vaddr;
	155
	156	vaddr = (unsigned long)GHES_IOREMAP_IRQ_PAGE(ghes_ioremap_area->addr);
	157	ioremap_page_range(vaddr, vaddr + PAGE_SIZE,
158	pfn << PAGE_SHIFT, PAGE_KERNEL);
159
160	return (void __iomem *)vaddr;
161	}
162
163	static void ghes_iounmap_nmi(void __iomem *vaddr_ptr)
164	{
165	unsigned long vaddr = (unsigned long __force)vaddr_ptr;
166	void *base = ghes_ioremap_area->addr;
167
168	BUG_ON(vaddr != (unsigned long)GHES_IOREMAP_NMI_PAGE(base));
169	unmap_kernel_range_noflush(vaddr, PAGE_SIZE);
170	__flush_tlb_one(vaddr);
171	}
172
173	static void ghes_iounmap_irq(void __iomem *vaddr_ptr)
174	{
175	unsigned long vaddr = (unsigned long __force)vaddr_ptr;
176	void *base = ghes_ioremap_area->addr;
177
178	BUG_ON(vaddr != (unsigned long)GHES_IOREMAP_IRQ_PAGE(base));
179	unmap_kernel_range_noflush(vaddr, PAGE_SIZE);
180	__flush_tlb_one(vaddr);
181	}
182
d334a491 HY	183	static struct ghes ghes_new(struct acpi_hest_generic generic)
	184	{
	185	struct ghes *ghes;
	186	unsigned int error_block_length;
	187	int rc;
	188
	189	ghes = kzalloc(sizeof(*ghes), GFP_KERNEL);
	190	if (!ghes)
	191	return ERR_PTR(-ENOMEM);
	192	ghes->generic = generic;
d334a491 HY	193	rc = acpi_pre_map_gar(&generic->error_status_address);
	194	if (rc)
	195	goto err_free;
	196	error_block_length = generic->error_block_length;
	197	if (error_block_length > GHES_ESTATUS_MAX_SIZE) {
	198	pr_warning(FW_WARN GHES_PFX
	199	"Error status block length is too long: %u for "
	200	"generic hardware error source: %d.\n",
	201	error_block_length, generic->header.source_id);
	202	error_block_length = GHES_ESTATUS_MAX_SIZE;
	203	}
	204	ghes->estatus = kmalloc(error_block_length, GFP_KERNEL);
	205	if (!ghes->estatus) {
	206	rc = -ENOMEM;
	207	goto err_unmap;
	208	}
	209
	210	return ghes;
	211
	212	err_unmap:
	213	acpi_post_unmap_gar(&generic->error_status_address);
	214	err_free:
	215	kfree(ghes);
	216	return ERR_PTR(rc);
	217	}
	218
	219	static void ghes_fini(struct ghes *ghes)
	220	{
	221	kfree(ghes->estatus);
	222	acpi_post_unmap_gar(&ghes->generic->error_status_address);
	223	}
	224
	225	enum {
ad4ecef2 HY	226	GHES_SEV_NO = 0x0,
	227	GHES_SEV_CORRECTED = 0x1,
	228	GHES_SEV_RECOVERABLE = 0x2,
	229	GHES_SEV_PANIC = 0x3,
d334a491 HY	230	};
	231
	232	static inline int ghes_severity(int severity)
	233	{
	234	switch (severity) {
ad4ecef2 HY	235	case CPER_SEV_INFORMATIONAL:
	236	return GHES_SEV_NO;
	237	case CPER_SEV_CORRECTED:
	238	return GHES_SEV_CORRECTED;
	239	case CPER_SEV_RECOVERABLE:
	240	return GHES_SEV_RECOVERABLE;
	241	case CPER_SEV_FATAL:
	242	return GHES_SEV_PANIC;
d334a491	243	default:
25985edc	244	/* Unknown, go panic */
ad4ecef2	245	return GHES_SEV_PANIC;
d334a491 HY	246	}
	247	}
	248
81e88fdc HY	249	static void ghes_copy_tofrom_phys(void *buffer, u64 paddr, u32 len,
81e88fdc HY	250	int from_phys)
d334a491	251	{
81e88fdc HY	252	void __iomem *vaddr;
	253	unsigned long flags = 0;
	254	int in_nmi = in_nmi();
	255	u64 offset;
	256	u32 trunk;
	257
	258	while (len > 0) {
	259	offset = paddr - (paddr & PAGE_MASK);
	260	if (in_nmi) {
	261	raw_spin_lock(&ghes_ioremap_lock_nmi);
	262	vaddr = ghes_ioremap_pfn_nmi(paddr >> PAGE_SHIFT);
	263	} else {
	264	spin_lock_irqsave(&ghes_ioremap_lock_irq, flags);
	265	vaddr = ghes_ioremap_pfn_irq(paddr >> PAGE_SHIFT);
	266	}
	267	trunk = PAGE_SIZE - offset;
	268	trunk = min(trunk, len);
	269	if (from_phys)
	270	memcpy_fromio(buffer, vaddr + offset, trunk);
	271	else
	272	memcpy_toio(vaddr + offset, buffer, trunk);
	273	len -= trunk;
	274	paddr += trunk;
	275	buffer += trunk;
	276	if (in_nmi) {
	277	ghes_iounmap_nmi(vaddr);
	278	raw_spin_unlock(&ghes_ioremap_lock_nmi);
	279	} else {
	280	ghes_iounmap_irq(vaddr);
	281	spin_unlock_irqrestore(&ghes_ioremap_lock_irq, flags);
	282	}
	283	}
d334a491 HY	284	}
	285
	286	static int ghes_read_estatus(struct ghes *ghes, int silent)
	287	{
	288	struct acpi_hest_generic *g = ghes->generic;
	289	u64 buf_paddr;
	290	u32 len;
	291	int rc;
	292
	293	rc = acpi_atomic_read(&buf_paddr, &g->error_status_address);
	294	if (rc) {
	295	if (!silent && printk_ratelimit())
	296	pr_warning(FW_WARN GHES_PFX
	297	"Failed to read error status block address for hardware error source: %d.\n",
	298	g->header.source_id);
	299	return -EIO;
	300	}
	301	if (!buf_paddr)
	302	return -ENOENT;
	303
81e88fdc HY	304	ghes_copy_tofrom_phys(ghes->estatus, buf_paddr,
81e88fdc HY	305	sizeof(*ghes->estatus), 1);
d334a491 HY	306	if (!ghes->estatus->block_status)
	307	return -ENOENT;
	308
	309	ghes->buffer_paddr = buf_paddr;
	310	ghes->flags \|= GHES_TO_CLEAR;
	311
	312	rc = -EIO;
	313	len = apei_estatus_len(ghes->estatus);
	314	if (len < sizeof(*ghes->estatus))
	315	goto err_read_block;
	316	if (len > ghes->generic->error_block_length)
	317	goto err_read_block;
	318	if (apei_estatus_check_header(ghes->estatus))
	319	goto err_read_block;
81e88fdc HY	320	ghes_copy_tofrom_phys(ghes->estatus + 1,
	321	buf_paddr + sizeof(*ghes->estatus),
	322	len - sizeof(*ghes->estatus), 1);
d334a491 HY	323	if (apei_estatus_check(ghes->estatus))
	324	goto err_read_block;
	325	rc = 0;
	326
	327	err_read_block:
81e88fdc	328	if (rc && !silent && printk_ratelimit())
d334a491 HY	329	pr_warning(FW_WARN GHES_PFX
	330	"Failed to read error status block!\n");
	331	return rc;
	332	}
	333
	334	static void ghes_clear_estatus(struct ghes *ghes)
	335	{
	336	ghes->estatus->block_status = 0;
	337	if (!(ghes->flags & GHES_TO_CLEAR))
	338	return;
	339	ghes_copy_tofrom_phys(ghes->estatus, ghes->buffer_paddr,
	340	sizeof(ghes->estatus->block_status), 0);
	341	ghes->flags &= ~GHES_TO_CLEAR;
	342	}
	343
	344	static void ghes_do_proc(struct ghes *ghes)
	345	{
ad4ecef2	346	int sev, processed = 0;
d334a491 HY	347	struct acpi_hest_generic_data *gdata;
d334a491 HY	348
ad4ecef2	349	sev = ghes_severity(ghes->estatus->error_severity);
d334a491 HY	350	apei_estatus_for_each_section(ghes->estatus, gdata) {
	351	#ifdef CONFIG_X86_MCE
	352	if (!uuid_le_cmp((uuid_le )gdata->section_type,
	353	CPER_SEC_PLATFORM_MEM)) {
	354	apei_mce_report_mem_error(
ad4ecef2	355	sev == GHES_SEV_CORRECTED,
d334a491 HY	356	(struct cper_sec_mem_err *)(gdata+1));
	357	processed = 1;
	358	}
	359	#endif
	360	}
32c361f5	361	}
d334a491	362
32c361f5 HY	363	static void ghes_print_estatus(const char pfx, struct ghes ghes)
	364	{
	365	/* Not more than 2 messages every 5 seconds */
	366	static DEFINE_RATELIMIT_STATE(ratelimit, 5*HZ, 2);
	367
	368	if (pfx == NULL) {
	369	if (ghes_severity(ghes->estatus->error_severity) <=
	370	GHES_SEV_CORRECTED)
	371	pfx = KERN_WARNING HW_ERR;
	372	else
	373	pfx = KERN_ERR HW_ERR;
	374	}
	375	if (__ratelimit(&ratelimit)) {
	376	printk(
	377	"%s""Hardware error from APEI Generic Hardware Error Source: %d\n",
	378	pfx, ghes->generic->header.source_id);
	379	apei_estatus_print(pfx, ghes->estatus);
	380	}
d334a491 HY	381	}
	382
	383	static int ghes_proc(struct ghes *ghes)
	384	{
	385	int rc;
	386
	387	rc = ghes_read_estatus(ghes, 0);
	388	if (rc)
	389	goto out;
32c361f5	390	ghes_print_estatus(NULL, ghes);
d334a491 HY	391	ghes_do_proc(ghes);
	392
	393	out:
	394	ghes_clear_estatus(ghes);
	395	return 0;
	396	}
	397
81e88fdc HY	398	static void ghes_add_timer(struct ghes *ghes)
	399	{
	400	struct acpi_hest_generic *g = ghes->generic;
	401	unsigned long expire;
	402
	403	if (!g->notify.poll_interval) {
	404	pr_warning(FW_WARN GHES_PFX "Poll interval is 0 for generic hardware error source: %d, disabled.\n",
	405	g->header.source_id);
	406	return;
	407	}
	408	expire = jiffies + msecs_to_jiffies(g->notify.poll_interval);
	409	ghes->timer.expires = round_jiffies_relative(expire);
	410	add_timer(&ghes->timer);
	411	}
	412
	413	static void ghes_poll_func(unsigned long data)
	414	{
	415	struct ghes ghes = (void )data;
	416
	417	ghes_proc(ghes);
	418	if (!(ghes->flags & GHES_EXITING))
	419	ghes_add_timer(ghes);
	420	}
	421
	422	static irqreturn_t ghes_irq_func(int irq, void *data)
	423	{
	424	struct ghes *ghes = data;
	425	int rc;
	426
	427	rc = ghes_proc(ghes);
	428	if (rc)
	429	return IRQ_NONE;
	430
	431	return IRQ_HANDLED;
	432	}
	433
d334a491 HY	434	static int ghes_notify_sci(struct notifier_block *this,
	435	unsigned long event, void *data)
	436	{
	437	struct ghes *ghes;
	438	int ret = NOTIFY_DONE;
	439
	440	rcu_read_lock();
	441	list_for_each_entry_rcu(ghes, &ghes_sci, list) {
	442	if (!ghes_proc(ghes))
	443	ret = NOTIFY_OK;
	444	}
	445	rcu_read_unlock();
	446
	447	return ret;
	448	}
	449
81e88fdc HY	450	static int ghes_notify_nmi(struct notifier_block *this,
	451	unsigned long cmd, void *data)
	452	{
	453	struct ghes ghes, ghes_global = NULL;
	454	int sev, sev_global = -1;
	455	int ret = NOTIFY_DONE;
	456
	457	if (cmd != DIE_NMI)
	458	return ret;
	459
	460	raw_spin_lock(&ghes_nmi_lock);
	461	list_for_each_entry_rcu(ghes, &ghes_nmi, list) {
	462	if (ghes_read_estatus(ghes, 1)) {
	463	ghes_clear_estatus(ghes);
	464	continue;
	465	}
	466	sev = ghes_severity(ghes->estatus->error_severity);
	467	if (sev > sev_global) {
	468	sev_global = sev;
	469	ghes_global = ghes;
	470	}
	471	ret = NOTIFY_STOP;
	472	}
	473
	474	if (ret == NOTIFY_DONE)
	475	goto out;
	476
	477	if (sev_global >= GHES_SEV_PANIC) {
	478	oops_begin();
	479	ghes_print_estatus(KERN_EMERG HW_ERR, ghes_global);
	480	/* reboot to log the error! */
	481	if (panic_timeout == 0)
	482	panic_timeout = ghes_panic_timeout;
	483	panic("Fatal hardware error!");
	484	}
	485
	486	list_for_each_entry_rcu(ghes, &ghes_nmi, list) {
	487	if (!(ghes->flags & GHES_TO_CLEAR))
	488	continue;
	489	/* Do not print estatus because printk is not NMI safe */
	490	ghes_do_proc(ghes);
	491	ghes_clear_estatus(ghes);
	492	}
	493
	494	out:
	495	raw_spin_unlock(&ghes_nmi_lock);
	496	return ret;
	497	}
	498
d334a491 HY	499	static struct notifier_block ghes_notifier_sci = {
	500	.notifier_call = ghes_notify_sci,
	501	};
	502
81e88fdc HY	503	static struct notifier_block ghes_notifier_nmi = {
	504	.notifier_call = ghes_notify_nmi,
	505	};
	506
7ad6e943	507	static int __devinit ghes_probe(struct platform_device *ghes_dev)
d334a491 HY	508	{
	509	struct acpi_hest_generic *generic;
	510	struct ghes *ghes = NULL;
7ad6e943	511	int rc = -EINVAL;
d334a491	512
1dd6b20e	513	generic = (struct acpi_hest_generic *)ghes_dev->dev.platform_data;
d334a491	514	if (!generic->enabled)
7ad6e943	515	return -ENODEV;
d334a491	516
81e88fdc HY	517	switch (generic->notify.type) {
	518	case ACPI_HEST_NOTIFY_POLLED:
	519	case ACPI_HEST_NOTIFY_EXTERNAL:
	520	case ACPI_HEST_NOTIFY_SCI:
	521	case ACPI_HEST_NOTIFY_NMI:
	522	break;
	523	case ACPI_HEST_NOTIFY_LOCAL:
	524	pr_warning(GHES_PFX "Generic hardware error source: %d notified via local interrupt is not supported!\n",
d334a491 HY	525	generic->header.source_id);
d334a491 HY	526	goto err;
81e88fdc HY	527	default:
	528	pr_warning(FW_WARN GHES_PFX "Unknown notification type: %u for generic hardware error source: %d\n",
	529	generic->notify.type, generic->header.source_id);
	530	goto err;
d334a491	531	}
81e88fdc HY	532
	533	rc = -EIO;
	534	if (generic->error_block_length <
	535	sizeof(struct acpi_hest_generic_status)) {
	536	pr_warning(FW_BUG GHES_PFX "Invalid error block length: %u for generic hardware error source: %d\n",
	537	generic->error_block_length,
d334a491 HY	538	generic->header.source_id);
	539	goto err;
	540	}
	541	ghes = ghes_new(generic);
	542	if (IS_ERR(ghes)) {
	543	rc = PTR_ERR(ghes);
	544	ghes = NULL;
	545	goto err;
	546	}
81e88fdc HY	547	switch (generic->notify.type) {
	548	case ACPI_HEST_NOTIFY_POLLED:
	549	ghes->timer.function = ghes_poll_func;
	550	ghes->timer.data = (unsigned long)ghes;
	551	init_timer_deferrable(&ghes->timer);
	552	ghes_add_timer(ghes);
	553	break;
	554	case ACPI_HEST_NOTIFY_EXTERNAL:
	555	/* External interrupt vector is GSI */
	556	if (acpi_gsi_to_irq(generic->notify.vector, &ghes->irq)) {
	557	pr_err(GHES_PFX "Failed to map GSI to IRQ for generic hardware error source: %d\n",
	558	generic->header.source_id);
	559	goto err;
	560	}
	561	if (request_irq(ghes->irq, ghes_irq_func,
	562	0, "GHES IRQ", ghes)) {
	563	pr_err(GHES_PFX "Failed to register IRQ for generic hardware error source: %d\n",
	564	generic->header.source_id);
	565	goto err;
	566	}
	567	break;
	568	case ACPI_HEST_NOTIFY_SCI:
7ad6e943	569	mutex_lock(&ghes_list_mutex);
d334a491 HY	570	if (list_empty(&ghes_sci))
	571	register_acpi_hed_notifier(&ghes_notifier_sci);
	572	list_add_rcu(&ghes->list, &ghes_sci);
7ad6e943	573	mutex_unlock(&ghes_list_mutex);
81e88fdc HY	574	break;
	575	case ACPI_HEST_NOTIFY_NMI:
	576	mutex_lock(&ghes_list_mutex);
	577	if (list_empty(&ghes_nmi))
	578	register_die_notifier(&ghes_notifier_nmi);
	579	list_add_rcu(&ghes->list, &ghes_nmi);
	580	mutex_unlock(&ghes_list_mutex);
	581	break;
	582	default:
	583	BUG();
d334a491	584	}
7ad6e943	585	platform_set_drvdata(ghes_dev, ghes);
d334a491 HY	586
	587	return 0;
	588	err:
7ad6e943	589	if (ghes) {
d334a491	590	ghes_fini(ghes);
7ad6e943 HY	591	kfree(ghes);
7ad6e943 HY	592	}
d334a491 HY	593	return rc;
	594	}
	595
7ad6e943	596	static int __devexit ghes_remove(struct platform_device *ghes_dev)
d334a491	597	{
7ad6e943 HY	598	struct ghes *ghes;
7ad6e943 HY	599	struct acpi_hest_generic *generic;
d334a491	600
7ad6e943 HY	601	ghes = platform_get_drvdata(ghes_dev);
	602	generic = ghes->generic;
	603
81e88fdc	604	ghes->flags \|= GHES_EXITING;
7ad6e943	605	switch (generic->notify.type) {
81e88fdc HY	606	case ACPI_HEST_NOTIFY_POLLED:
	607	del_timer_sync(&ghes->timer);
	608	break;
	609	case ACPI_HEST_NOTIFY_EXTERNAL:
	610	free_irq(ghes->irq, ghes);
	611	break;
7ad6e943 HY	612	case ACPI_HEST_NOTIFY_SCI:
	613	mutex_lock(&ghes_list_mutex);
	614	list_del_rcu(&ghes->list);
	615	if (list_empty(&ghes_sci))
	616	unregister_acpi_hed_notifier(&ghes_notifier_sci);
	617	mutex_unlock(&ghes_list_mutex);
	618	break;
81e88fdc HY	619	case ACPI_HEST_NOTIFY_NMI:
	620	mutex_lock(&ghes_list_mutex);
	621	list_del_rcu(&ghes->list);
	622	if (list_empty(&ghes_nmi))
	623	unregister_die_notifier(&ghes_notifier_nmi);
	624	mutex_unlock(&ghes_list_mutex);
	625	/*
	626	* To synchronize with NMI handler, ghes can only be
	627	* freed after NMI handler finishes.
	628	*/
	629	synchronize_rcu();
	630	break;
7ad6e943 HY	631	default:
	632	BUG();
	633	break;
	634	}
d334a491	635
7ad6e943 HY	636	ghes_fini(ghes);
7ad6e943 HY	637	kfree(ghes);
d334a491	638
7ad6e943 HY	639	platform_set_drvdata(ghes_dev, NULL);
	640
	641	return 0;
d334a491 HY	642	}
d334a491 HY	643
7ad6e943 HY	644	static struct platform_driver ghes_platform_driver = {
	645	.driver = {
	646	.name = "GHES",
	647	.owner = THIS_MODULE,
	648	},
	649	.probe = ghes_probe,
	650	.remove = ghes_remove,
	651	};
	652
d334a491 HY	653	static int __init ghes_init(void)
d334a491 HY	654	{
81e88fdc HY	655	int rc;
81e88fdc HY	656
d334a491 HY	657	if (acpi_disabled)
	658	return -ENODEV;
	659
	660	if (hest_disable) {
	661	pr_info(GHES_PFX "HEST is not enabled!\n");
	662	return -EINVAL;
	663	}
	664
81e88fdc HY	665	rc = ghes_ioremap_init();
	666	if (rc)
	667	goto err;
	668
	669	rc = platform_driver_register(&ghes_platform_driver);
	670	if (rc)
	671	goto err_ioremap_exit;
	672
	673	return 0;
	674	err_ioremap_exit:
	675	ghes_ioremap_exit();
	676	err:
	677	return rc;
d334a491 HY	678	}
	679
	680	static void __exit ghes_exit(void)
	681	{
7ad6e943	682	platform_driver_unregister(&ghes_platform_driver);
81e88fdc	683	ghes_ioremap_exit();
d334a491 HY	684	}
	685
	686	module_init(ghes_init);
	687	module_exit(ghes_exit);
	688
	689	MODULE_AUTHOR("Huang Ying");
	690	MODULE_DESCRIPTION("APEI Generic Hardware Error Source support");
	691	MODULE_LICENSE("GPL");
7ad6e943	692	MODULE_ALIAS("platform:GHES");