blob: 49d2f00019e5d8092f7f32e9b3c6dfc53cceeee6 [file] [log] [blame]
/*
* PowerNV OPAL high level interfaces
*
* Copyright 2011 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.
*/
#undef DEBUG
#include <linux/types.h>
#include <linux/of.h>
#include <linux/of_fdt.h>
#include <linux/of_platform.h>
#include <linux/interrupt.h>
#include <linux/notifier.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/kobject.h>
#include <linux/delay.h>
#include <linux/memblock.h>
#include <asm/opal.h>
#include <asm/firmware.h>
#include <asm/mce.h>
#include "powernv.h"
/* /sys/firmware/opal */
struct kobject *opal_kobj;
struct opal {
u64 base;
u64 entry;
u64 size;
} opal;
struct mcheck_recoverable_range {
u64 start_addr;
u64 end_addr;
u64 recover_addr;
};
static struct mcheck_recoverable_range *mc_recoverable_range;
static int mc_recoverable_range_len;
struct device_node *opal_node;
static DEFINE_SPINLOCK(opal_write_lock);
extern u64 opal_mc_secondary_handler[];
static unsigned int *opal_irqs;
static unsigned int opal_irq_count;
static ATOMIC_NOTIFIER_HEAD(opal_notifier_head);
static struct atomic_notifier_head opal_msg_notifier_head[OPAL_MSG_TYPE_MAX];
static DEFINE_SPINLOCK(opal_notifier_lock);
static uint64_t last_notified_mask = 0x0ul;
static atomic_t opal_notifier_hold = ATOMIC_INIT(0);
int __init early_init_dt_scan_opal(unsigned long node,
const char *uname, int depth, void *data)
{
const void *basep, *entryp, *sizep;
unsigned long basesz, entrysz, runtimesz;
if (depth != 1 || strcmp(uname, "ibm,opal") != 0)
return 0;
basep = of_get_flat_dt_prop(node, "opal-base-address", &basesz);
entryp = of_get_flat_dt_prop(node, "opal-entry-address", &entrysz);
sizep = of_get_flat_dt_prop(node, "opal-runtime-size", &runtimesz);
if (!basep || !entryp || !sizep)
return 1;
opal.base = of_read_number(basep, basesz/4);
opal.entry = of_read_number(entryp, entrysz/4);
opal.size = of_read_number(sizep, runtimesz/4);
pr_debug("OPAL Base = 0x%llx (basep=%p basesz=%ld)\n",
opal.base, basep, basesz);
pr_debug("OPAL Entry = 0x%llx (entryp=%p basesz=%ld)\n",
opal.entry, entryp, entrysz);
pr_debug("OPAL Entry = 0x%llx (sizep=%p runtimesz=%ld)\n",
opal.size, sizep, runtimesz);
powerpc_firmware_features |= FW_FEATURE_OPAL;
if (of_flat_dt_is_compatible(node, "ibm,opal-v3")) {
powerpc_firmware_features |= FW_FEATURE_OPALv2;
powerpc_firmware_features |= FW_FEATURE_OPALv3;
printk("OPAL V3 detected !\n");
} else if (of_flat_dt_is_compatible(node, "ibm,opal-v2")) {
powerpc_firmware_features |= FW_FEATURE_OPALv2;
printk("OPAL V2 detected !\n");
} else {
printk("OPAL V1 detected !\n");
}
return 1;
}
int __init early_init_dt_scan_recoverable_ranges(unsigned long node,
const char *uname, int depth, void *data)
{
unsigned long i, psize, size;
const __be32 *prop;
if (depth != 1 || strcmp(uname, "ibm,opal") != 0)
return 0;
prop = of_get_flat_dt_prop(node, "mcheck-recoverable-ranges", &psize);
if (!prop)
return 1;
pr_debug("Found machine check recoverable ranges.\n");
/*
* Calculate number of available entries.
*
* Each recoverable address range entry is (start address, len,
* recovery address), 2 cells each for start and recovery address,
* 1 cell for len, totalling 5 cells per entry.
*/
mc_recoverable_range_len = psize / (sizeof(*prop) * 5);
/* Sanity check */
if (!mc_recoverable_range_len)
return 1;
/* Size required to hold all the entries. */
size = mc_recoverable_range_len *
sizeof(struct mcheck_recoverable_range);
/*
* Allocate a buffer to hold the MC recoverable ranges. We would be
* accessing them in real mode, hence it needs to be within
* RMO region.
*/
mc_recoverable_range =__va(memblock_alloc_base(size, __alignof__(u64),
ppc64_rma_size));
memset(mc_recoverable_range, 0, size);
for (i = 0; i < mc_recoverable_range_len; i++) {
mc_recoverable_range[i].start_addr =
of_read_number(prop + (i * 5) + 0, 2);
mc_recoverable_range[i].end_addr =
mc_recoverable_range[i].start_addr +
of_read_number(prop + (i * 5) + 2, 1);
mc_recoverable_range[i].recover_addr =
of_read_number(prop + (i * 5) + 3, 2);
pr_debug("Machine check recoverable range: %llx..%llx: %llx\n",
mc_recoverable_range[i].start_addr,
mc_recoverable_range[i].end_addr,
mc_recoverable_range[i].recover_addr);
}
return 1;
}
static int __init opal_register_exception_handlers(void)
{
#ifdef __BIG_ENDIAN__
u64 glue;
if (!(powerpc_firmware_features & FW_FEATURE_OPAL))
return -ENODEV;
/* Hookup some exception handlers except machine check. We use the
* fwnmi area at 0x7000 to provide the glue space to OPAL
*/
glue = 0x7000;
opal_register_exception_handler(OPAL_HYPERVISOR_MAINTENANCE_HANDLER,
0, glue);
glue += 128;
opal_register_exception_handler(OPAL_SOFTPATCH_HANDLER, 0, glue);
#endif
return 0;
}
early_initcall(opal_register_exception_handlers);
int opal_notifier_register(struct notifier_block *nb)
{
if (!nb) {
pr_warning("%s: Invalid argument (%p)\n",
__func__, nb);
return -EINVAL;
}
atomic_notifier_chain_register(&opal_notifier_head, nb);
return 0;
}
EXPORT_SYMBOL_GPL(opal_notifier_register);
int opal_notifier_unregister(struct notifier_block *nb)
{
if (!nb) {
pr_warning("%s: Invalid argument (%p)\n",
__func__, nb);
return -EINVAL;
}
atomic_notifier_chain_unregister(&opal_notifier_head, nb);
return 0;
}
EXPORT_SYMBOL_GPL(opal_notifier_unregister);
static void opal_do_notifier(uint64_t events)
{
unsigned long flags;
uint64_t changed_mask;
if (atomic_read(&opal_notifier_hold))
return;
spin_lock_irqsave(&opal_notifier_lock, flags);
changed_mask = last_notified_mask ^ events;
last_notified_mask = events;
spin_unlock_irqrestore(&opal_notifier_lock, flags);
/*
* We feed with the event bits and changed bits for
* enough information to the callback.
*/
atomic_notifier_call_chain(&opal_notifier_head,
events, (void *)changed_mask);
}
void opal_notifier_update_evt(uint64_t evt_mask,
uint64_t evt_val)
{
unsigned long flags;
spin_lock_irqsave(&opal_notifier_lock, flags);
last_notified_mask &= ~evt_mask;
last_notified_mask |= evt_val;
spin_unlock_irqrestore(&opal_notifier_lock, flags);
}
void opal_notifier_enable(void)
{
int64_t rc;
uint64_t evt = 0;
atomic_set(&opal_notifier_hold, 0);
/* Process pending events */
rc = opal_poll_events(&evt);
if (rc == OPAL_SUCCESS && evt)
opal_do_notifier(evt);
}
void opal_notifier_disable(void)
{
atomic_set(&opal_notifier_hold, 1);
}
/*
* Opal message notifier based on message type. Allow subscribers to get
* notified for specific messgae type.
*/
int opal_message_notifier_register(enum OpalMessageType msg_type,
struct notifier_block *nb)
{
if (!nb) {
pr_warning("%s: Invalid argument (%p)\n",
__func__, nb);
return -EINVAL;
}
if (msg_type > OPAL_MSG_TYPE_MAX) {
pr_warning("%s: Invalid message type argument (%d)\n",
__func__, msg_type);
return -EINVAL;
}
return atomic_notifier_chain_register(
&opal_msg_notifier_head[msg_type], nb);
}
static void opal_message_do_notify(uint32_t msg_type, void *msg)
{
/* notify subscribers */
atomic_notifier_call_chain(&opal_msg_notifier_head[msg_type],
msg_type, msg);
}
static void opal_handle_message(void)
{
s64 ret;
/*
* TODO: pre-allocate a message buffer depending on opal-msg-size
* value in /proc/device-tree.
*/
static struct opal_msg msg;
u32 type;
ret = opal_get_msg(__pa(&msg), sizeof(msg));
/* No opal message pending. */
if (ret == OPAL_RESOURCE)
return;
/* check for errors. */
if (ret) {
pr_warning("%s: Failed to retrive opal message, err=%lld\n",
__func__, ret);
return;
}
type = be32_to_cpu(msg.msg_type);
/* Sanity check */
if (type > OPAL_MSG_TYPE_MAX) {
pr_warning("%s: Unknown message type: %u\n", __func__, type);
return;
}
opal_message_do_notify(type, (void *)&msg);
}
static int opal_message_notify(struct notifier_block *nb,
unsigned long events, void *change)
{
if (events & OPAL_EVENT_MSG_PENDING)
opal_handle_message();
return 0;
}
static struct notifier_block opal_message_nb = {
.notifier_call = opal_message_notify,
.next = NULL,
.priority = 0,
};
static int __init opal_message_init(void)
{
int ret, i;
for (i = 0; i < OPAL_MSG_TYPE_MAX; i++)
ATOMIC_INIT_NOTIFIER_HEAD(&opal_msg_notifier_head[i]);
ret = opal_notifier_register(&opal_message_nb);
if (ret) {
pr_err("%s: Can't register OPAL event notifier (%d)\n",
__func__, ret);
return ret;
}
return 0;
}
early_initcall(opal_message_init);
int opal_get_chars(uint32_t vtermno, char *buf, int count)
{
s64 rc;
__be64 evt, len;
if (!opal.entry)
return -ENODEV;
opal_poll_events(&evt);
if ((be64_to_cpu(evt) & OPAL_EVENT_CONSOLE_INPUT) == 0)
return 0;
len = cpu_to_be64(count);
rc = opal_console_read(vtermno, &len, buf);
if (rc == OPAL_SUCCESS)
return be64_to_cpu(len);
return 0;
}
int opal_put_chars(uint32_t vtermno, const char *data, int total_len)
{
int written = 0;
__be64 olen;
s64 len, rc;
unsigned long flags;
__be64 evt;
if (!opal.entry)
return -ENODEV;
/* We want put_chars to be atomic to avoid mangling of hvsi
* packets. To do that, we first test for room and return
* -EAGAIN if there isn't enough.
*
* Unfortunately, opal_console_write_buffer_space() doesn't
* appear to work on opal v1, so we just assume there is
* enough room and be done with it
*/
spin_lock_irqsave(&opal_write_lock, flags);
if (firmware_has_feature(FW_FEATURE_OPALv2)) {
rc = opal_console_write_buffer_space(vtermno, &olen);
len = be64_to_cpu(olen);
if (rc || len < total_len) {
spin_unlock_irqrestore(&opal_write_lock, flags);
/* Closed -> drop characters */
if (rc)
return total_len;
opal_poll_events(NULL);
return -EAGAIN;
}
}
/* We still try to handle partial completions, though they
* should no longer happen.
*/
rc = OPAL_BUSY;
while(total_len > 0 && (rc == OPAL_BUSY ||
rc == OPAL_BUSY_EVENT || rc == OPAL_SUCCESS)) {
olen = cpu_to_be64(total_len);
rc = opal_console_write(vtermno, &olen, data);
len = be64_to_cpu(olen);
/* Closed or other error drop */
if (rc != OPAL_SUCCESS && rc != OPAL_BUSY &&
rc != OPAL_BUSY_EVENT) {
written = total_len;
break;
}
if (rc == OPAL_SUCCESS) {
total_len -= len;
data += len;
written += len;
}
/* This is a bit nasty but we need that for the console to
* flush when there aren't any interrupts. We will clean
* things a bit later to limit that to synchronous path
* such as the kernel console and xmon/udbg
*/
do
opal_poll_events(&evt);
while(rc == OPAL_SUCCESS &&
(be64_to_cpu(evt) & OPAL_EVENT_CONSOLE_OUTPUT));
}
spin_unlock_irqrestore(&opal_write_lock, flags);
return written;
}
static int opal_recover_mce(struct pt_regs *regs,
struct machine_check_event *evt)
{
int recovered = 0;
uint64_t ea = get_mce_fault_addr(evt);
if (!(regs->msr & MSR_RI)) {
/* If MSR_RI isn't set, we cannot recover */
recovered = 0;
} else if (evt->disposition == MCE_DISPOSITION_RECOVERED) {
/* Platform corrected itself */
recovered = 1;
} else if (ea && !is_kernel_addr(ea)) {
/*
* Faulting address is not in kernel text. We should be fine.
* We need to find which process uses this address.
* For now, kill the task if we have received exception when
* in userspace.
*
* TODO: Queue up this address for hwpoisioning later.
*/
if (user_mode(regs) && !is_global_init(current)) {
_exception(SIGBUS, regs, BUS_MCEERR_AR, regs->nip);
recovered = 1;
} else
recovered = 0;
} else if (user_mode(regs) && !is_global_init(current) &&
evt->severity == MCE_SEV_ERROR_SYNC) {
/*
* If we have received a synchronous error when in userspace
* kill the task.
*/
_exception(SIGBUS, regs, BUS_MCEERR_AR, regs->nip);
recovered = 1;
}
return recovered;
}
int opal_machine_check(struct pt_regs *regs)
{
struct machine_check_event evt;
if (!get_mce_event(&evt, MCE_EVENT_RELEASE))
return 0;
/* Print things out */
if (evt.version != MCE_V1) {
pr_err("Machine Check Exception, Unknown event version %d !\n",
evt.version);
return 0;
}
machine_check_print_event_info(&evt);
if (opal_recover_mce(regs, &evt))
return 1;
return 0;
}
static uint64_t find_recovery_address(uint64_t nip)
{
int i;
for (i = 0; i < mc_recoverable_range_len; i++)
if ((nip >= mc_recoverable_range[i].start_addr) &&
(nip < mc_recoverable_range[i].end_addr))
return mc_recoverable_range[i].recover_addr;
return 0;
}
bool opal_mce_check_early_recovery(struct pt_regs *regs)
{
uint64_t recover_addr = 0;
if (!opal.base || !opal.size)
goto out;
if ((regs->nip >= opal.base) &&
(regs->nip <= (opal.base + opal.size)))
recover_addr = find_recovery_address(regs->nip);
/*
* Setup regs->nip to rfi into fixup address.
*/
if (recover_addr)
regs->nip = recover_addr;
out:
return !!recover_addr;
}
static irqreturn_t opal_interrupt(int irq, void *data)
{
__be64 events;
opal_handle_interrupt(virq_to_hw(irq), &events);
opal_do_notifier(events);
return IRQ_HANDLED;
}
static int opal_sysfs_init(void)
{
opal_kobj = kobject_create_and_add("opal", firmware_kobj);
if (!opal_kobj) {
pr_warn("kobject_create_and_add opal failed\n");
return -ENOMEM;
}
return 0;
}
static int __init opal_init(void)
{
struct device_node *np, *consoles;
const __be32 *irqs;
int rc, i, irqlen;
opal_node = of_find_node_by_path("/ibm,opal");
if (!opal_node) {
pr_warn("opal: Node not found\n");
return -ENODEV;
}
/* Register OPAL consoles if any ports */
if (firmware_has_feature(FW_FEATURE_OPALv2))
consoles = of_find_node_by_path("/ibm,opal/consoles");
else
consoles = of_node_get(opal_node);
if (consoles) {
for_each_child_of_node(consoles, np) {
if (strcmp(np->name, "serial"))
continue;
of_platform_device_create(np, NULL, NULL);
}
of_node_put(consoles);
}
/* Find all OPAL interrupts and request them */
irqs = of_get_property(opal_node, "opal-interrupts", &irqlen);
pr_debug("opal: Found %d interrupts reserved for OPAL\n",
irqs ? (irqlen / 4) : 0);
opal_irq_count = irqlen / 4;
opal_irqs = kzalloc(opal_irq_count * sizeof(unsigned int), GFP_KERNEL);
for (i = 0; irqs && i < (irqlen / 4); i++, irqs++) {
unsigned int hwirq = be32_to_cpup(irqs);
unsigned int irq = irq_create_mapping(NULL, hwirq);
if (irq == NO_IRQ) {
pr_warning("opal: Failed to map irq 0x%x\n", hwirq);
continue;
}
rc = request_irq(irq, opal_interrupt, 0, "opal", NULL);
if (rc)
pr_warning("opal: Error %d requesting irq %d"
" (0x%x)\n", rc, irq, hwirq);
opal_irqs[i] = irq;
}
/* Create "opal" kobject under /sys/firmware */
rc = opal_sysfs_init();
if (rc == 0) {
/* Setup error log interface */
rc = opal_elog_init();
/* Setup code update interface */
opal_flash_init();
/* Setup platform dump extract interface */
opal_platform_dump_init();
/* Setup system parameters interface */
opal_sys_param_init();
/* Setup message log interface. */
opal_msglog_init();
}
return 0;
}
subsys_initcall(opal_init);
void opal_shutdown(void)
{
unsigned int i;
long rc = OPAL_BUSY;
/* First free interrupts, which will also mask them */
for (i = 0; i < opal_irq_count; i++) {
if (opal_irqs[i])
free_irq(opal_irqs[i], NULL);
opal_irqs[i] = 0;
}
/*
* Then sync with OPAL which ensure anything that can
* potentially write to our memory has completed such
* as an ongoing dump retrieval
*/
while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
rc = opal_sync_host_reboot();
if (rc == OPAL_BUSY)
opal_poll_events(NULL);
else
mdelay(10);
}
}
/* Export this so that test modules can use it */
EXPORT_SYMBOL_GPL(opal_invalid_call);