--- /dev/null
+/*
+ * Copyright 2010, 2011 Mark Nelson and Tseng-Hui (Frank) Lin, IBM Corporation
+ *
+ * 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.
+ */
+
+#ifndef _ASM_POWERPC_IO_EVENT_IRQ_H
+#define _ASM_POWERPC_IO_EVENT_IRQ_H
+
+#include <linux/types.h>
+#include <linux/notifier.h>
+
+#define PSERIES_IOEI_RPC_MAX_LEN 216
+
+#define PSERIES_IOEI_TYPE_ERR_DETECTED 0x01
+#define PSERIES_IOEI_TYPE_ERR_RECOVERED 0x02
+#define PSERIES_IOEI_TYPE_EVENT 0x03
+#define PSERIES_IOEI_TYPE_RPC_PASS_THRU 0x04
+
+#define PSERIES_IOEI_SUBTYPE_NOT_APP 0x00
+#define PSERIES_IOEI_SUBTYPE_REBALANCE_REQ 0x01
+#define PSERIES_IOEI_SUBTYPE_NODE_ONLINE 0x03
+#define PSERIES_IOEI_SUBTYPE_NODE_OFFLINE 0x04
+#define PSERIES_IOEI_SUBTYPE_DUMP_SIZE_CHANGE 0x05
+#define PSERIES_IOEI_SUBTYPE_TORRENT_IRV_UPDATE 0x06
+#define PSERIES_IOEI_SUBTYPE_TORRENT_HFI_CFGED 0x07
+
+#define PSERIES_IOEI_SCOPE_NOT_APP 0x00
+#define PSERIES_IOEI_SCOPE_RIO_HUB 0x36
+#define PSERIES_IOEI_SCOPE_RIO_BRIDGE 0x37
+#define PSERIES_IOEI_SCOPE_PHB 0x38
+#define PSERIES_IOEI_SCOPE_EADS_GLOBAL 0x39
+#define PSERIES_IOEI_SCOPE_EADS_SLOT 0x3A
+#define PSERIES_IOEI_SCOPE_TORRENT_HUB 0x3B
+#define PSERIES_IOEI_SCOPE_SERVICE_PROC 0x51
+
+/* Platform Event Log Format, Version 6, data portition of IO event section */
+struct pseries_io_event {
+ uint8_t event_type; /* 0x00 IO-Event Type */
+ uint8_t rpc_data_len; /* 0x01 RPC data length */
+ uint8_t scope; /* 0x02 Error/Event Scope */
+ uint8_t event_subtype; /* 0x03 I/O-Event Sub-Type */
+ uint32_t drc_index; /* 0x04 DRC Index */
+ uint8_t rpc_data[PSERIES_IOEI_RPC_MAX_LEN];
+ /* 0x08 RPC Data (0-216 bytes, */
+ /* padded to 4 bytes alignment) */
+};
+
+extern struct atomic_notifier_head pseries_ioei_notifier_list;
+
+#endif /* _ASM_POWERPC_IO_EVENT_IRQ_H */
--- /dev/null
+/*
+ * Copyright 2010 2011 Mark Nelson and Tseng-Hui (Frank) Lin, IBM Corporation
+ *
+ * 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/errno.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/of.h>
+#include <linux/list.h>
+#include <linux/notifier.h>
+
+#include <asm/machdep.h>
+#include <asm/rtas.h>
+#include <asm/irq.h>
+#include <asm/io_event_irq.h>
+
+#include "pseries.h"
+
+/*
+ * IO event interrupt is a mechanism provided by RTAS to return
+ * information about hardware error and non-error events. Device
+ * drivers can register their event handlers to receive events.
+ * Device drivers are expected to use atomic_notifier_chain_register()
+ * and atomic_notifier_chain_unregister() to register and unregister
+ * their event handlers. Since multiple IO event types and scopes
+ * share an IO event interrupt, the event handlers are called one
+ * by one until the IO event is claimed by one of the handlers.
+ * The event handlers are expected to return NOTIFY_OK if the
+ * event is handled by the event handler or NOTIFY_DONE if the
+ * event does not belong to the handler.
+ *
+ * Usage:
+ *
+ * Notifier function:
+ * #include <asm/io_event_irq.h>
+ * int event_handler(struct notifier_block *nb, unsigned long val, void *data) {
+ * p = (struct pseries_io_event_sect_data *) data;
+ * if (! is_my_event(p->scope, p->event_type)) return NOTIFY_DONE;
+ * :
+ * :
+ * return NOTIFY_OK;
+ * }
+ * struct notifier_block event_nb = {
+ * .notifier_call = event_handler,
+ * }
+ *
+ * Registration:
+ * atomic_notifier_chain_register(&pseries_ioei_notifier_list, &event_nb);
+ *
+ * Unregistration:
+ * atomic_notifier_chain_unregister(&pseries_ioei_notifier_list, &event_nb);
+ */
+
+ATOMIC_NOTIFIER_HEAD(pseries_ioei_notifier_list);
+EXPORT_SYMBOL_GPL(pseries_ioei_notifier_list);
+
+static int ioei_check_exception_token;
+
+/* pSeries event log format */
+
+/* Two bytes ASCII section IDs */
+#define PSERIES_ELOG_SECT_ID_PRIV_HDR (('P' << 8) | 'H')
+#define PSERIES_ELOG_SECT_ID_USER_HDR (('U' << 8) | 'H')
+#define PSERIES_ELOG_SECT_ID_PRIMARY_SRC (('P' << 8) | 'S')
+#define PSERIES_ELOG_SECT_ID_EXTENDED_UH (('E' << 8) | 'H')
+#define PSERIES_ELOG_SECT_ID_FAILING_MTMS (('M' << 8) | 'T')
+#define PSERIES_ELOG_SECT_ID_SECONDARY_SRC (('S' << 8) | 'S')
+#define PSERIES_ELOG_SECT_ID_DUMP_LOCATOR (('D' << 8) | 'H')
+#define PSERIES_ELOG_SECT_ID_FW_ERROR (('S' << 8) | 'W')
+#define PSERIES_ELOG_SECT_ID_IMPACT_PART_ID (('L' << 8) | 'P')
+#define PSERIES_ELOG_SECT_ID_LOGIC_RESOURCE_ID (('L' << 8) | 'R')
+#define PSERIES_ELOG_SECT_ID_HMC_ID (('H' << 8) | 'M')
+#define PSERIES_ELOG_SECT_ID_EPOW (('E' << 8) | 'P')
+#define PSERIES_ELOG_SECT_ID_IO_EVENT (('I' << 8) | 'E')
+#define PSERIES_ELOG_SECT_ID_MANUFACT_INFO (('M' << 8) | 'I')
+#define PSERIES_ELOG_SECT_ID_CALL_HOME (('C' << 8) | 'H')
+#define PSERIES_ELOG_SECT_ID_USER_DEF (('U' << 8) | 'D')
+
+/* Vendor specific Platform Event Log Format, Version 6, section header */
+struct pseries_elog_section {
+ uint16_t id; /* 0x00 2-byte ASCII section ID */
+ uint16_t length; /* 0x02 Section length in bytes */
+ uint8_t version; /* 0x04 Section version */
+ uint8_t subtype; /* 0x05 Section subtype */
+ uint16_t creator_component; /* 0x06 Creator component ID */
+ uint8_t data[]; /* 0x08 Start of section data */
+};
+
+static char ioei_rtas_buf[RTAS_DATA_BUF_SIZE] __cacheline_aligned;
+
+/**
+ * Find data portion of a specific section in RTAS extended event log.
+ * @elog: RTAS error/event log.
+ * @sect_id: secsion ID.
+ *
+ * Return:
+ * pointer to the section data of the specified section
+ * NULL if not found
+ */
+static struct pseries_elog_section *find_xelog_section(struct rtas_error_log *elog,
+ uint16_t sect_id)
+{
+ struct rtas_ext_event_log_v6 *xelog =
+ (struct rtas_ext_event_log_v6 *) elog->buffer;
+ struct pseries_elog_section *sect;
+ unsigned char *p, *log_end;
+
+ /* Check that we understand the format */
+ if (elog->extended_log_length < sizeof(struct rtas_ext_event_log_v6) ||
+ xelog->log_format != RTAS_V6EXT_LOG_FORMAT_EVENT_LOG ||
+ xelog->company_id != RTAS_V6EXT_COMPANY_ID_IBM)
+ return NULL;
+
+ log_end = elog->buffer + elog->extended_log_length;
+ p = xelog->vendor_log;
+ while (p < log_end) {
+ sect = (struct pseries_elog_section *)p;
+ if (sect->id == sect_id)
+ return sect;
+ p += sect->length;
+ }
+ return NULL;
+}
+
+/**
+ * Find the data portion of an IO Event section from event log.
+ * @elog: RTAS error/event log.
+ *
+ * Return:
+ * pointer to a valid IO event section data. NULL if not found.
+ */
+static struct pseries_io_event * ioei_find_event(struct rtas_error_log *elog)
+{
+ struct pseries_elog_section *sect;
+
+ /* We should only ever get called for io-event interrupts, but if
+ * we do get called for another type then something went wrong so
+ * make some noise about it.
+ * RTAS_TYPE_IO only exists in extended event log version 6 or later.
+ * No need to check event log version.
+ */
+ if (unlikely(elog->type != RTAS_TYPE_IO)) {
+ printk_once(KERN_WARNING "io_event_irq: Unexpected event type %d",
+ elog->type);
+ return NULL;
+ }
+
+ sect = find_xelog_section(elog, PSERIES_ELOG_SECT_ID_IO_EVENT);
+ if (unlikely(!sect)) {
+ printk_once(KERN_WARNING "io_event_irq: RTAS extended event "
+ "log does not contain an IO Event section. "
+ "Could be a bug in system firmware!\n");
+ return NULL;
+ }
+ return (struct pseries_io_event *) §->data;
+}
+
+/*
+ * PAPR:
+ * - check-exception returns the first found error or event and clear that
+ * error or event so it is reported once.
+ * - Each interrupt returns one event. If a plateform chooses to report
+ * multiple events through a single interrupt, it must ensure that the
+ * interrupt remains asserted until check-exception has been used to
+ * process all out-standing events for that interrupt.
+ *
+ * Implementation notes:
+ * - Events must be processed in the order they are returned. Hence,
+ * sequential in nature.
+ * - The owner of an event is determined by combinations of scope,
+ * event type, and sub-type. There is no easy way to pre-sort clients
+ * by scope or event type alone. For example, Torrent ISR route change
+ * event is reported with scope 0x00 (Not Applicatable) rather than
+ * 0x3B (Torrent-hub). It is better to let the clients to identify
+ * who owns the the event.
+ */
+
+static irqreturn_t ioei_interrupt(int irq, void *dev_id)
+{
+ struct pseries_io_event *event;
+ int rtas_rc;
+
+ for (;;) {
+ rtas_rc = rtas_call(ioei_check_exception_token, 6, 1, NULL,
+ RTAS_VECTOR_EXTERNAL_INTERRUPT,
+ virq_to_hw(irq),
+ RTAS_IO_EVENTS, 1 /* Time Critical */,
+ __pa(ioei_rtas_buf),
+ RTAS_DATA_BUF_SIZE);
+ if (rtas_rc != 0)
+ break;
+
+ event = ioei_find_event((struct rtas_error_log *)ioei_rtas_buf);
+ if (!event)
+ continue;
+
+ atomic_notifier_call_chain(&pseries_ioei_notifier_list,
+ 0, event);
+ }
+ return IRQ_HANDLED;
+}
+
+static int __init ioei_init(void)
+{
+ struct device_node *np;
+
+ ioei_check_exception_token = rtas_token("check-exception");
+ if (ioei_check_exception_token == RTAS_UNKNOWN_SERVICE) {
+ pr_warning("IO Event IRQ not supported on this system !\n");
+ return -ENODEV;
+ }
+ np = of_find_node_by_path("/event-sources/ibm,io-events");
+ if (np) {
+ request_event_sources_irqs(np, ioei_interrupt, "IO_EVENT");
+ of_node_put(np);
+ } else {
+ pr_err("io_event_irq: No ibm,io-events on system! "
+ "IO Event interrupt disabled.\n");
+ return -ENODEV;
+ }
+ return 0;
+}
+machine_subsys_initcall(pseries, ioei_init);
+