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
|
/*
* MSI support for PPC4xx SoCs using High Speed Transfer Assist (HSTA) for
* generation of the interrupt.
*
* Copyright © 2013 Alistair Popple <alistair@popple.id.au> 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/kernel.h>
#include <linux/interrupt.h>
#include <linux/msi.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/pci.h>
#include <linux/semaphore.h>
#include <asm/msi_bitmap.h>
#include <asm/ppc-pci.h>
struct ppc4xx_hsta_msi {
struct device *dev;
/* The ioremapped HSTA MSI IO space */
u32 __iomem *data;
/* Physical address of HSTA MSI IO space */
u64 address;
struct msi_bitmap bmp;
/* An array mapping offsets to hardware IRQs */
int *irq_map;
/* Number of hwirqs supported */
int irq_count;
};
static struct ppc4xx_hsta_msi ppc4xx_hsta_msi;
static int hsta_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
{
struct msi_msg msg;
struct msi_desc *entry;
int irq, hwirq;
u64 addr;
/* We don't support MSI-X */
if (type == PCI_CAP_ID_MSIX) {
pr_debug("%s: MSI-X not supported.\n", __func__);
return -EINVAL;
}
for_each_pci_msi_entry(entry, dev) {
irq = msi_bitmap_alloc_hwirqs(&ppc4xx_hsta_msi.bmp, 1);
if (irq < 0) {
pr_debug("%s: Failed to allocate msi interrupt\n",
__func__);
return irq;
}
hwirq = ppc4xx_hsta_msi.irq_map[irq];
if (hwirq == NO_IRQ) {
pr_err("%s: Failed mapping irq %d\n", __func__, irq);
return -EINVAL;
}
/*
* HSTA generates interrupts on writes to 128-bit aligned
* addresses.
*/
addr = ppc4xx_hsta_msi.address + irq*0x10;
msg.address_hi = upper_32_bits(addr);
msg.address_lo = lower_32_bits(addr);
/* Data is not used by the HSTA. */
msg.data = 0;
pr_debug("%s: Setup irq %d (0x%0llx)\n", __func__, hwirq,
(((u64) msg.address_hi) << 32) | msg.address_lo);
if (irq_set_msi_desc(hwirq, entry)) {
pr_err(
"%s: Invalid hwirq %d specified in device tree\n",
__func__, hwirq);
msi_bitmap_free_hwirqs(&ppc4xx_hsta_msi.bmp, irq, 1);
return -EINVAL;
}
pci_write_msi_msg(hwirq, &msg);
}
return 0;
}
static int hsta_find_hwirq_offset(int hwirq)
{
int irq;
/* Find the offset given the hwirq */
for (irq = 0; irq < ppc4xx_hsta_msi.irq_count; irq++)
if (ppc4xx_hsta_msi.irq_map[irq] == hwirq)
return irq;
return -EINVAL;
}
static void hsta_teardown_msi_irqs(struct pci_dev *dev)
{
struct msi_desc *entry;
int irq;
for_each_pci_msi_entry(entry, dev) {
if (entry->irq == NO_IRQ)
continue;
irq = hsta_find_hwirq_offset(entry->irq);
/* entry->irq should always be in irq_map */
BUG_ON(irq < 0);
irq_set_msi_desc(entry->irq, NULL);
msi_bitmap_free_hwirqs(&ppc4xx_hsta_msi.bmp, irq, 1);
pr_debug("%s: Teardown IRQ %u (index %u)\n", __func__,
entry->irq, irq);
}
}
static int hsta_msi_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct resource *mem;
int irq, ret, irq_count;
struct pci_controller *phb;
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (IS_ERR(mem)) {
dev_err(dev, "Unable to get mmio space\n");
return -EINVAL;
}
irq_count = of_irq_count(dev->of_node);
if (!irq_count) {
dev_err(dev, "Unable to find IRQ range\n");
return -EINVAL;
}
ppc4xx_hsta_msi.dev = dev;
ppc4xx_hsta_msi.address = mem->start;
ppc4xx_hsta_msi.data = ioremap(mem->start, resource_size(mem));
ppc4xx_hsta_msi.irq_count = irq_count;
if (!ppc4xx_hsta_msi.data) {
dev_err(dev, "Unable to map memory\n");
return -ENOMEM;
}
ret = msi_bitmap_alloc(&ppc4xx_hsta_msi.bmp, irq_count, dev->of_node);
if (ret)
goto out;
ppc4xx_hsta_msi.irq_map = kmalloc(sizeof(int) * irq_count, GFP_KERNEL);
if (IS_ERR(ppc4xx_hsta_msi.irq_map)) {
ret = -ENOMEM;
goto out1;
}
/* Setup a mapping from irq offsets to hardware irq numbers */
for (irq = 0; irq < irq_count; irq++) {
ppc4xx_hsta_msi.irq_map[irq] =
irq_of_parse_and_map(dev->of_node, irq);
if (ppc4xx_hsta_msi.irq_map[irq] == NO_IRQ) {
dev_err(dev, "Unable to map IRQ\n");
ret = -EINVAL;
goto out2;
}
}
list_for_each_entry(phb, &hose_list, list_node) {
phb->controller_ops.setup_msi_irqs = hsta_setup_msi_irqs;
phb->controller_ops.teardown_msi_irqs = hsta_teardown_msi_irqs;
}
return 0;
out2:
kfree(ppc4xx_hsta_msi.irq_map);
out1:
msi_bitmap_free(&ppc4xx_hsta_msi.bmp);
out:
iounmap(ppc4xx_hsta_msi.data);
return ret;
}
static const struct of_device_id hsta_msi_ids[] = {
{
.compatible = "ibm,hsta-msi",
},
{}
};
static struct platform_driver hsta_msi_driver = {
.probe = hsta_msi_probe,
.driver = {
.name = "hsta-msi",
.of_match_table = hsta_msi_ids,
},
};
static int hsta_msi_init(void)
{
return platform_driver_register(&hsta_msi_driver);
}
subsys_initcall(hsta_msi_init);
|
