1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
|
/*
* 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)
return -ENODEV;
np = of_find_node_by_path("/event-sources/ibm,io-events");
if (np) {
request_event_sources_irqs(np, ioei_interrupt, "IO_EVENT");
pr_info("IBM I/O event interrupts enabled\n");
of_node_put(np);
} else {
return -ENODEV;
}
return 0;
}
machine_subsys_initcall(pseries, ioei_init);
|
