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
230
231
232
233
234
235
236
237
|
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/irq.h>
#include <linux/smp.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/cpu.h>
#include <linux/of.h>
#include <linux/spinlock.h>
#include <linux/msi.h>
#include <asm/prom.h>
#include <asm/smp.h>
#include <asm/machdep.h>
#include <asm/irq.h>
#include <asm/errno.h>
#include <asm/xics.h>
#include <asm/rtas.h>
/* RTAS service tokens */
static int ibm_get_xive;
static int ibm_set_xive;
static int ibm_int_on;
static int ibm_int_off;
static int ics_rtas_map(struct ics *ics, unsigned int virq);
static void ics_rtas_mask_unknown(struct ics *ics, unsigned long vec);
static long ics_rtas_get_server(struct ics *ics, unsigned long vec);
static int ics_rtas_host_match(struct ics *ics, struct device_node *node);
/* Only one global & state struct ics */
static struct ics ics_rtas = {
.map = ics_rtas_map,
.mask_unknown = ics_rtas_mask_unknown,
.get_server = ics_rtas_get_server,
.host_match = ics_rtas_host_match,
};
static void ics_rtas_unmask_irq(struct irq_data *d)
{
unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
int call_status;
int server;
pr_devel("xics: unmask virq %d [hw 0x%x]\n", d->irq, hw_irq);
if (hw_irq == XICS_IPI || hw_irq == XICS_IRQ_SPURIOUS)
return;
server = xics_get_irq_server(d->irq, d->affinity, 0);
call_status = rtas_call(ibm_set_xive, 3, 1, NULL, hw_irq, server,
DEFAULT_PRIORITY);
if (call_status != 0) {
printk(KERN_ERR
"%s: ibm_set_xive irq %u server %x returned %d\n",
__func__, hw_irq, server, call_status);
return;
}
/* Now unmask the interrupt (often a no-op) */
call_status = rtas_call(ibm_int_on, 1, 1, NULL, hw_irq);
if (call_status != 0) {
printk(KERN_ERR "%s: ibm_int_on irq=%u returned %d\n",
__func__, hw_irq, call_status);
return;
}
}
static unsigned int ics_rtas_startup(struct irq_data *d)
{
#ifdef CONFIG_PCI_MSI
/*
* The generic MSI code returns with the interrupt disabled on the
* card, using the MSI mask bits. Firmware doesn't appear to unmask
* at that level, so we do it here by hand.
*/
if (irq_data_get_msi_desc(d))
pci_msi_unmask_irq(d);
#endif
/* unmask it */
ics_rtas_unmask_irq(d);
return 0;
}
static void ics_rtas_mask_real_irq(unsigned int hw_irq)
{
int call_status;
if (hw_irq == XICS_IPI)
return;
call_status = rtas_call(ibm_int_off, 1, 1, NULL, hw_irq);
if (call_status != 0) {
printk(KERN_ERR "%s: ibm_int_off irq=%u returned %d\n",
__func__, hw_irq, call_status);
return;
}
/* Have to set XIVE to 0xff to be able to remove a slot */
call_status = rtas_call(ibm_set_xive, 3, 1, NULL, hw_irq,
xics_default_server, 0xff);
if (call_status != 0) {
printk(KERN_ERR "%s: ibm_set_xive(0xff) irq=%u returned %d\n",
__func__, hw_irq, call_status);
return;
}
}
static void ics_rtas_mask_irq(struct irq_data *d)
{
unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
pr_devel("xics: mask virq %d [hw 0x%x]\n", d->irq, hw_irq);
if (hw_irq == XICS_IPI || hw_irq == XICS_IRQ_SPURIOUS)
return;
ics_rtas_mask_real_irq(hw_irq);
}
static int ics_rtas_set_affinity(struct irq_data *d,
const struct cpumask *cpumask,
bool force)
{
unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
int status;
int xics_status[2];
int irq_server;
if (hw_irq == XICS_IPI || hw_irq == XICS_IRQ_SPURIOUS)
return -1;
status = rtas_call(ibm_get_xive, 1, 3, xics_status, hw_irq);
if (status) {
printk(KERN_ERR "%s: ibm,get-xive irq=%u returns %d\n",
__func__, hw_irq, status);
return -1;
}
irq_server = xics_get_irq_server(d->irq, cpumask, 1);
if (irq_server == -1) {
pr_warning("%s: No online cpus in the mask %*pb for irq %d\n",
__func__, cpumask_pr_args(cpumask), d->irq);
return -1;
}
status = rtas_call(ibm_set_xive, 3, 1, NULL,
hw_irq, irq_server, xics_status[1]);
if (status) {
printk(KERN_ERR "%s: ibm,set-xive irq=%u returns %d\n",
__func__, hw_irq, status);
return -1;
}
return IRQ_SET_MASK_OK;
}
static struct irq_chip ics_rtas_irq_chip = {
.name = "XICS",
.irq_startup = ics_rtas_startup,
.irq_mask = ics_rtas_mask_irq,
.irq_unmask = ics_rtas_unmask_irq,
.irq_eoi = NULL, /* Patched at init time */
.irq_set_affinity = ics_rtas_set_affinity
};
static int ics_rtas_map(struct ics *ics, unsigned int virq)
{
unsigned int hw_irq = (unsigned int)virq_to_hw(virq);
int status[2];
int rc;
if (WARN_ON(hw_irq == XICS_IPI || hw_irq == XICS_IRQ_SPURIOUS))
return -EINVAL;
/* Check if RTAS knows about this interrupt */
rc = rtas_call(ibm_get_xive, 1, 3, status, hw_irq);
if (rc)
return -ENXIO;
irq_set_chip_and_handler(virq, &ics_rtas_irq_chip, handle_fasteoi_irq);
irq_set_chip_data(virq, &ics_rtas);
return 0;
}
static void ics_rtas_mask_unknown(struct ics *ics, unsigned long vec)
{
ics_rtas_mask_real_irq(vec);
}
static long ics_rtas_get_server(struct ics *ics, unsigned long vec)
{
int rc, status[2];
rc = rtas_call(ibm_get_xive, 1, 3, status, vec);
if (rc)
return -1;
return status[0];
}
static int ics_rtas_host_match(struct ics *ics, struct device_node *node)
{
/* IBM machines have interrupt parents of various funky types for things
* like vdevices, events, etc... The trick we use here is to match
* everything here except the legacy 8259 which is compatible "chrp,iic"
*/
return !of_device_is_compatible(node, "chrp,iic");
}
__init int ics_rtas_init(void)
{
ibm_get_xive = rtas_token("ibm,get-xive");
ibm_set_xive = rtas_token("ibm,set-xive");
ibm_int_on = rtas_token("ibm,int-on");
ibm_int_off = rtas_token("ibm,int-off");
/* We enable the RTAS "ICS" if RTAS is present with the
* appropriate tokens
*/
if (ibm_get_xive == RTAS_UNKNOWN_SERVICE ||
ibm_set_xive == RTAS_UNKNOWN_SERVICE)
return -ENODEV;
/* We need to patch our irq chip's EOI to point to the
* right ICP
*/
ics_rtas_irq_chip.irq_eoi = icp_ops->eoi;
/* Register ourselves */
xics_register_ics(&ics_rtas);
return 0;
}
|
