[PATCH v2] powerpc/powernv: Platform dump interface
Vasant Hegde
hegdevasant at linux.vnet.ibm.com
Thu Jan 16 23:16:00 EST 2014
This patch adds interface to retrieve FSP and Platform dump.
Flow:
- We register for OPAL notification events.
- OPAL sends new dump available notification.
- We retrieve the dump via OPAL interface and send it to debugfs.
- User copies the dump data and end ACKs via debugfs.
- We send ACK to OPAL.
OPAL APIs:
- opal_dump_init()
- opal_dump_info()
- opal_dump_read()
- opal_dump_ack()
- opal_dump_resend_notification()
debugfs files:
We create below dump related files under "fsp" directory.
- dump : Dump data
- dump_available : New dump available notification to userspace
- dump_control : ACK dump. Also initiate new FSP dump
- README : README
Signed-off-by: Vasant Hegde <hegdevasant at linux.vnet.ibm.com>
---
Ben,
I have rebased this patch on top of your next branch.
-Vasant
arch/powerpc/include/asm/opal.h | 12 +
arch/powerpc/platforms/powernv/Makefile | 2
arch/powerpc/platforms/powernv/opal-dump.c | 436 ++++++++++++++++++++++++
arch/powerpc/platforms/powernv/opal-wrappers.S | 5
arch/powerpc/platforms/powernv/opal.c | 2
5 files changed, 456 insertions(+), 1 deletion(-)
create mode 100644 arch/powerpc/platforms/powernv/opal-dump.c
diff --git a/arch/powerpc/include/asm/opal.h b/arch/powerpc/include/asm/opal.h
index 9a87b44..0f4c7ff 100644
--- a/arch/powerpc/include/asm/opal.h
+++ b/arch/powerpc/include/asm/opal.h
@@ -154,8 +154,13 @@ extern int opal_enter_rtas(struct rtas_args *args,
#define OPAL_FLASH_VALIDATE 76
#define OPAL_FLASH_MANAGE 77
#define OPAL_FLASH_UPDATE 78
+#define OPAL_DUMP_INIT 81
+#define OPAL_DUMP_INFO 82
+#define OPAL_DUMP_READ 83
+#define OPAL_DUMP_ACK 84
#define OPAL_GET_MSG 85
#define OPAL_CHECK_ASYNC_COMPLETION 86
+#define OPAL_DUMP_RESEND 91
#ifndef __ASSEMBLY__
@@ -236,6 +241,7 @@ enum OpalPendingState {
OPAL_EVENT_EPOW = 0x80,
OPAL_EVENT_LED_STATUS = 0x100,
OPAL_EVENT_PCI_ERROR = 0x200,
+ OPAL_EVENT_DUMP_AVAIL = 0x400,
OPAL_EVENT_MSG_PENDING = 0x800,
};
@@ -825,6 +831,11 @@ int64_t opal_lpc_read(uint32_t chip_id, enum OpalLPCAddressType addr_type,
int64_t opal_validate_flash(uint64_t buffer, uint32_t *size, uint32_t *result);
int64_t opal_manage_flash(uint8_t op);
int64_t opal_update_flash(uint64_t blk_list);
+int64_t opal_dump_init(uint8_t dump_type);
+int64_t opal_dump_info(uint32_t *dump_id, uint32_t *dump_size);
+int64_t opal_dump_read(uint32_t dump_id, uint64_t buffer);
+int64_t opal_dump_ack(uint32_t dump_id);
+int64_t opal_dump_resend_notification(void);
int64_t opal_get_msg(uint64_t buffer, size_t size);
int64_t opal_check_completion(uint64_t buffer, size_t size, uint64_t token);
@@ -859,6 +870,7 @@ extern void opal_get_rtc_time(struct rtc_time *tm);
extern unsigned long opal_get_boot_time(void);
extern void opal_nvram_init(void);
extern void opal_flash_init(void);
+extern void opal_platform_dump_init(void);
extern int opal_machine_check(struct pt_regs *regs);
diff --git a/arch/powerpc/platforms/powernv/Makefile b/arch/powerpc/platforms/powernv/Makefile
index 8d767fd..3528c11 100644
--- a/arch/powerpc/platforms/powernv/Makefile
+++ b/arch/powerpc/platforms/powernv/Makefile
@@ -1,6 +1,6 @@
obj-y += setup.o opal-takeover.o opal-wrappers.o opal.o
obj-y += opal-rtc.o opal-nvram.o opal-lpc.o opal-flash.o
-obj-y += rng.o
+obj-y += rng.o opal-dump.o
obj-$(CONFIG_SMP) += smp.o
obj-$(CONFIG_PCI) += pci.o pci-p5ioc2.o pci-ioda.o
diff --git a/arch/powerpc/platforms/powernv/opal-dump.c b/arch/powerpc/platforms/powernv/opal-dump.c
new file mode 100644
index 0000000..4447027
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/opal-dump.c
@@ -0,0 +1,436 @@
+/*
+ * PowerNV OPAL Dump Interface
+ *
+ * Copyright 2013 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/kobject.h>
+#include <linux/debugfs.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/pagemap.h>
+#include <linux/delay.h>
+
+#include <asm/opal.h>
+
+/* Dump type */
+#define DUMP_TYPE_FSP 0x01
+
+/* Extract failed */
+#define DUMP_NACK_ID 0x00
+
+/* Dump record */
+struct dump_record {
+ uint8_t type;
+ uint32_t id;
+ uint32_t size;
+ char *buffer;
+};
+static struct dump_record dump_record;
+
+/* Dump available status */
+static u32 dump_avail;
+
+/* Binary blobs */
+static struct debugfs_blob_wrapper dump_blob;
+static struct debugfs_blob_wrapper readme_blob;
+
+/* Ignore dump notification, if we fail to create debugfs files */
+static bool dump_disarmed = false;
+
+
+static void free_dump_sg_list(struct opal_sg_list *list)
+{
+ struct opal_sg_list *sg1;
+ while (list) {
+ sg1 = list->next;
+ kfree(list);
+ list = sg1;
+ }
+ list = NULL;
+}
+
+/*
+ * Build dump buffer scatter gather list
+ */
+static struct opal_sg_list *dump_data_to_sglist(void)
+{
+ struct opal_sg_list *sg1, *list = NULL;
+ void *addr;
+ int64_t size;
+
+ addr = dump_record.buffer;
+ size = dump_record.size;
+
+ sg1 = kzalloc(PAGE_SIZE, GFP_KERNEL);
+ if (!sg1)
+ goto nomem;
+
+ list = sg1;
+ sg1->num_entries = 0;
+ while (size > 0) {
+ /* Translate virtual address to physical address */
+ sg1->entry[sg1->num_entries].data =
+ (void *)(vmalloc_to_pfn(addr) << PAGE_SHIFT);
+
+ if (size > PAGE_SIZE)
+ sg1->entry[sg1->num_entries].length = PAGE_SIZE;
+ else
+ sg1->entry[sg1->num_entries].length = size;
+
+ sg1->num_entries++;
+ if (sg1->num_entries >= SG_ENTRIES_PER_NODE) {
+ sg1->next = kzalloc(PAGE_SIZE, GFP_KERNEL);
+ if (!sg1->next)
+ goto nomem;
+
+ sg1 = sg1->next;
+ sg1->num_entries = 0;
+ }
+ addr += PAGE_SIZE;
+ size -= PAGE_SIZE;
+ }
+ return list;
+
+nomem:
+ pr_err("%s : Failed to allocate memory\n", __func__);
+ free_dump_sg_list(list);
+ return NULL;
+}
+
+/*
+ * Translate sg list address to absolute
+ */
+static void sglist_to_phy_addr(struct opal_sg_list *list)
+{
+ struct opal_sg_list *sg, *next;
+
+ for (sg = list; sg; sg = next) {
+ next = sg->next;
+ /* Don't translate NULL pointer for last entry */
+ if (sg->next)
+ sg->next = (struct opal_sg_list *)__pa(sg->next);
+ else
+ sg->next = NULL;
+
+ /* Convert num_entries to length */
+ sg->num_entries =
+ sg->num_entries * sizeof(struct opal_sg_entry) + 16;
+ }
+}
+
+static void free_dump_data_buf(void)
+{
+ vfree(dump_record.buffer);
+ dump_record.size = 0;
+}
+
+/*
+ * Allocate dump data buffer.
+ */
+static int alloc_dump_data_buf(void)
+{
+ dump_record.buffer = vzalloc(PAGE_ALIGN(dump_record.size));
+ if (!dump_record.buffer) {
+ pr_err("%s : Failed to allocate memory\n", __func__);
+ return -ENOMEM;
+ }
+ return 0;
+}
+
+/*
+ * Initiate FipS dump
+ */
+static int64_t dump_fips_init(uint8_t type)
+{
+ int rc;
+
+ rc = opal_dump_init(type);
+ if (rc)
+ pr_warn("%s: Failed to initiate FipS dump (%d)\n",
+ __func__, rc);
+ return rc;
+}
+
+/*
+ * Get dump ID and size.
+ */
+static int64_t dump_read_info(void)
+{
+ int rc;
+
+ rc = opal_dump_info(&dump_record.id, &dump_record.size);
+ if (rc)
+ pr_warn("%s: Failed to get dump info (%d)\n",
+ __func__, rc);
+ return rc;
+}
+
+/*
+ * Send acknowledgement to OPAL
+ */
+static int64_t dump_send_ack(uint32_t dump_id)
+{
+ int rc;
+
+ rc = opal_dump_ack(dump_id);
+ if (rc)
+ pr_warn("%s: Failed to send ack to Dump ID 0x%x (%d)\n",
+ __func__, dump_id, rc);
+ return rc;
+}
+
+/*
+ * Retrieve dump data
+ */
+static int64_t dump_read_data(void)
+{
+ struct opal_sg_list *list;
+ uint64_t addr;
+ int64_t rc;
+
+ /* Allocate memory */
+ rc = alloc_dump_data_buf();
+ if (rc)
+ goto out;
+
+ /* Generate SG list */
+ list = dump_data_to_sglist();
+ if (!list) {
+ rc = -ENOMEM;
+ goto out;
+ }
+
+ /* Translate sg list addr to real address */
+ sglist_to_phy_addr(list);
+
+ /* First entry address */
+ addr = __pa(list);
+
+ /* Fetch data */
+ rc = OPAL_BUSY_EVENT;
+ while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
+ rc = opal_dump_read(dump_record.id, addr);
+ if (rc == OPAL_BUSY_EVENT) {
+ opal_poll_events(NULL);
+ msleep(10);
+ }
+ }
+
+ if (rc != OPAL_SUCCESS && rc != OPAL_PARTIAL)
+ pr_warn("%s: Extract dump failed for ID 0x%x\n",
+ __func__, dump_record.id);
+
+ /* Free SG list */
+ free_dump_sg_list(list);
+
+out:
+ return rc;
+}
+
+static int extract_dump(void)
+{
+ int rc;
+
+ /* Get dump ID, size */
+ rc = dump_read_info();
+ if (rc != OPAL_SUCCESS)
+ return rc;
+
+ /* Read dump data */
+ rc = dump_read_data();
+ if (rc != OPAL_SUCCESS && rc != OPAL_PARTIAL) {
+ /*
+ * Failed to allocate memory to retrieve dump. Lets send
+ * negative ack so that we get notification again.
+ */
+ dump_send_ack(DUMP_NACK_ID);
+
+ /* Free dump buffer */
+ free_dump_data_buf();
+
+ return rc;
+ }
+ if (rc == OPAL_PARTIAL)
+ pr_info("%s: Platform dump partially read. ID = 0x%x\n",
+ __func__, dump_record.id);
+ else
+ pr_info("%s: New platform dump available. ID = 0x%x\n",
+ __func__, dump_record.id);
+
+ /* Update dump blob */
+ dump_blob.data = (void *)dump_record.buffer;
+ dump_blob.size = dump_record.size;
+
+ /* Update dump available status */
+ dump_avail = 1;
+
+ return rc;
+}
+
+static void dump_extract_fn(struct work_struct *work)
+{
+ extract_dump();
+}
+
+static DECLARE_WORK(dump_work, dump_extract_fn);
+
+/* Workqueue to extract dump */
+static void schedule_extract_dump(void)
+{
+ schedule_work(&dump_work);
+}
+
+/*
+ * New dump available notification
+ *
+ * Once we get notification, we extract dump via OPAL call
+ * and then pass dump to userspace via debugfs interface.
+ */
+static int dump_event(struct notifier_block *nb,
+ unsigned long events, void *change)
+{
+ /*
+ * Don't retrieve dump, if we don't have debugfs
+ * interface to pass data to userspace.
+ */
+ if (dump_disarmed)
+ return 0;
+
+ /* Check for dump available notification */
+ if (events & OPAL_EVENT_DUMP_AVAIL)
+ schedule_extract_dump();
+
+ return 0;
+}
+
+static struct notifier_block dump_nb = {
+ .notifier_call = dump_event,
+ .next = NULL,
+ .priority = 0
+};
+
+
+/* debugfs README message */
+static const char readme_msg[] =
+ "Platform dump HOWTO:\n\n"
+ "files:\n"
+ " dump - Binary file, contains actual dump data\n"
+ " dump_available (r--) - New dump available notification\n"
+ " 0 : No dump available\n"
+ " 1 : New dump available\n"
+ " dump_control(-w-) - Dump control file\n"
+ " 1 : Send acknowledgement (dump copied)\n"
+ " 2 : Initiate FipS dump\n";
+
+/* debugfs dump_control file operations */
+static ssize_t dump_control_write(struct file *file,
+ const char __user *user_buf,
+ size_t count, loff_t *ppos)
+{
+ char buf[4];
+ size_t buf_size;
+
+ buf_size = min(count, (sizeof(buf) - 1));
+ if (copy_from_user(buf, user_buf, buf_size))
+ return -EFAULT;
+
+ switch (buf[0]) {
+ case '1': /* Dump send ack */
+ if (dump_avail) {
+ dump_avail = 0;
+ free_dump_data_buf();
+ dump_send_ack(dump_record.id);
+ }
+ break;
+ case '2': /* Initiate FipS dump */
+ dump_fips_init(DUMP_TYPE_FSP);
+ break;
+ default:
+ break;
+ }
+ return count;
+}
+
+static const struct file_operations dump_control_fops = {
+ .open = simple_open,
+ .write = dump_control_write,
+ .llseek = default_llseek,
+};
+
+/*
+ * Create dump debugfs file
+ */
+static int debugfs_dump_init(void)
+{
+ struct dentry *dir, *file;
+
+ /* FSP dump directory */
+ dir = debugfs_create_dir("fsp", NULL);
+ if (!dir)
+ goto out;
+
+ /* README */
+ readme_blob.data = (void *)readme_msg;
+ readme_blob.size = strlen(readme_msg);
+ file = debugfs_create_blob("README", 0400, dir, &readme_blob);
+ if (!file)
+ goto remove_dir;
+
+ /* Dump available notification */
+ file = debugfs_create_u32("dump_avail", 0400, dir, &dump_avail);
+ if (!file)
+ goto remove_dir;
+
+ /* data file */
+ dump_blob.data = (void *)dump_record.buffer;
+ dump_blob.size = dump_record.size;
+ file = debugfs_create_blob("dump", 0400, dir, &dump_blob);
+ if (!file)
+ goto remove_dir;
+
+ /* Control file */
+ file = debugfs_create_file("dump_control", 0200, dir,
+ NULL, &dump_control_fops);
+ if (!file)
+ goto remove_dir;
+
+ return 0;
+
+remove_dir:
+ debugfs_remove_recursive(dir);
+
+out:
+ dump_disarmed = true;
+ return -1;
+}
+
+void __init opal_platform_dump_init(void)
+{
+ int rc;
+
+ /* debugfs interface */
+ rc = debugfs_dump_init();
+ if (rc) {
+ pr_warn("%s: Failed to create debugfs interface (%d)\n",
+ __func__, rc);
+ return;
+ }
+
+ /* Register for opal notifier */
+ rc = opal_notifier_register(&dump_nb);
+ if (rc) {
+ pr_warn("%s: Can't register OPAL event notifier (%d)\n",
+ __func__, rc);
+ return;
+ }
+
+ /* Request to resend dump available notification */
+ opal_dump_resend_notification();
+}
diff --git a/arch/powerpc/platforms/powernv/opal-wrappers.S b/arch/powerpc/platforms/powernv/opal-wrappers.S
index 719aa5c..c1e979b 100644
--- a/arch/powerpc/platforms/powernv/opal-wrappers.S
+++ b/arch/powerpc/platforms/powernv/opal-wrappers.S
@@ -126,5 +126,10 @@ OPAL_CALL(opal_return_cpu, OPAL_RETURN_CPU);
OPAL_CALL(opal_validate_flash, OPAL_FLASH_VALIDATE);
OPAL_CALL(opal_manage_flash, OPAL_FLASH_MANAGE);
OPAL_CALL(opal_update_flash, OPAL_FLASH_UPDATE);
+OPAL_CALL(opal_dump_init, OPAL_DUMP_INIT);
+OPAL_CALL(opal_dump_info, OPAL_DUMP_INFO);
+OPAL_CALL(opal_dump_read, OPAL_DUMP_READ);
+OPAL_CALL(opal_dump_ack, OPAL_DUMP_ACK);
OPAL_CALL(opal_get_msg, OPAL_GET_MSG);
OPAL_CALL(opal_check_completion, OPAL_CHECK_ASYNC_COMPLETION);
+OPAL_CALL(opal_dump_resend_notification, OPAL_DUMP_RESEND);
diff --git a/arch/powerpc/platforms/powernv/opal.c b/arch/powerpc/platforms/powernv/opal.c
index 7a184a0..1b00e99 100644
--- a/arch/powerpc/platforms/powernv/opal.c
+++ b/arch/powerpc/platforms/powernv/opal.c
@@ -473,6 +473,8 @@ static int __init opal_init(void)
if (rc == 0) {
/* Setup code update interface */
opal_flash_init();
+ /* Setup platform dump extract interface */
+ opal_platform_dump_init();
}
return 0;
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