1 /*
2 * Copyright (C) 2017 Marvell
3 *
4 * Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
5 *
6 * This file is licensed under the terms of the GNU General Public
7 * License version 2. This program is licensed "as is" without any
8 * warranty of any kind, whether express or implied.
9 */
10
11 #include <linux/io.h>
12 #include <linux/irq.h>
13 #include <linux/irqdomain.h>
14 #include <linux/msi.h>
15 #include <linux/of.h>
16 #include <linux/of_irq.h>
17 #include <linux/of_platform.h>
18 #include <linux/platform_device.h>
19
20 #include <dt-bindings/interrupt-controller/arm-gic.h>
21
22 #define GICP_SETSPI_NSR_OFFSET 0x0
23 #define GICP_CLRSPI_NSR_OFFSET 0x8
24
25 struct mvebu_gicp_spi_range {
26 unsigned int start;
27 unsigned int count;
28 };
29
30 struct mvebu_gicp {
31 struct mvebu_gicp_spi_range *spi_ranges;
32 unsigned int spi_ranges_cnt;
33 unsigned int spi_cnt;
34 unsigned long *spi_bitmap;
35 spinlock_t spi_lock;
36 struct resource *res;
37 struct device *dev;
38 };
39
gicp_idx_to_spi(struct mvebu_gicp * gicp,int idx)40 static int gicp_idx_to_spi(struct mvebu_gicp *gicp, int idx)
41 {
42 int i;
43
44 for (i = 0; i < gicp->spi_ranges_cnt; i++) {
45 struct mvebu_gicp_spi_range *r = &gicp->spi_ranges[i];
46
47 if (idx < r->count)
48 return r->start + idx;
49
50 idx -= r->count;
51 }
52
53 return -EINVAL;
54 }
55
gicp_compose_msi_msg(struct irq_data * data,struct msi_msg * msg)56 static void gicp_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
57 {
58 struct mvebu_gicp *gicp = data->chip_data;
59 phys_addr_t setspi = gicp->res->start + GICP_SETSPI_NSR_OFFSET;
60 phys_addr_t clrspi = gicp->res->start + GICP_CLRSPI_NSR_OFFSET;
61
62 msg[0].data = data->hwirq;
63 msg[0].address_lo = lower_32_bits(setspi);
64 msg[0].address_hi = upper_32_bits(setspi);
65 msg[1].data = data->hwirq;
66 msg[1].address_lo = lower_32_bits(clrspi);
67 msg[1].address_hi = upper_32_bits(clrspi);
68 }
69
70 static struct irq_chip gicp_irq_chip = {
71 .name = "GICP",
72 .irq_mask = irq_chip_mask_parent,
73 .irq_unmask = irq_chip_unmask_parent,
74 .irq_eoi = irq_chip_eoi_parent,
75 .irq_set_affinity = irq_chip_set_affinity_parent,
76 .irq_set_type = irq_chip_set_type_parent,
77 .irq_compose_msi_msg = gicp_compose_msi_msg,
78 };
79
gicp_irq_domain_alloc(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs,void * args)80 static int gicp_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
81 unsigned int nr_irqs, void *args)
82 {
83 struct mvebu_gicp *gicp = domain->host_data;
84 struct irq_fwspec fwspec;
85 unsigned int hwirq;
86 int ret;
87
88 spin_lock(&gicp->spi_lock);
89 hwirq = find_first_zero_bit(gicp->spi_bitmap, gicp->spi_cnt);
90 if (hwirq == gicp->spi_cnt) {
91 spin_unlock(&gicp->spi_lock);
92 return -ENOSPC;
93 }
94 __set_bit(hwirq, gicp->spi_bitmap);
95 spin_unlock(&gicp->spi_lock);
96
97 fwspec.fwnode = domain->parent->fwnode;
98 fwspec.param_count = 3;
99 fwspec.param[0] = GIC_SPI;
100 fwspec.param[1] = gicp_idx_to_spi(gicp, hwirq) - 32;
101 /*
102 * Assume edge rising for now, it will be properly set when
103 * ->set_type() is called
104 */
105 fwspec.param[2] = IRQ_TYPE_EDGE_RISING;
106
107 ret = irq_domain_alloc_irqs_parent(domain, virq, 1, &fwspec);
108 if (ret) {
109 dev_err(gicp->dev, "Cannot allocate parent IRQ\n");
110 goto free_hwirq;
111 }
112
113 ret = irq_domain_set_hwirq_and_chip(domain, virq, hwirq,
114 &gicp_irq_chip, gicp);
115 if (ret)
116 goto free_irqs_parent;
117
118 return 0;
119
120 free_irqs_parent:
121 irq_domain_free_irqs_parent(domain, virq, nr_irqs);
122 free_hwirq:
123 spin_lock(&gicp->spi_lock);
124 __clear_bit(hwirq, gicp->spi_bitmap);
125 spin_unlock(&gicp->spi_lock);
126 return ret;
127 }
128
gicp_irq_domain_free(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs)129 static void gicp_irq_domain_free(struct irq_domain *domain,
130 unsigned int virq, unsigned int nr_irqs)
131 {
132 struct mvebu_gicp *gicp = domain->host_data;
133 struct irq_data *d = irq_domain_get_irq_data(domain, virq);
134
135 if (d->hwirq >= gicp->spi_cnt) {
136 dev_err(gicp->dev, "Invalid hwirq %lu\n", d->hwirq);
137 return;
138 }
139
140 irq_domain_free_irqs_parent(domain, virq, nr_irqs);
141
142 spin_lock(&gicp->spi_lock);
143 __clear_bit(d->hwirq, gicp->spi_bitmap);
144 spin_unlock(&gicp->spi_lock);
145 }
146
147 static const struct irq_domain_ops gicp_domain_ops = {
148 .alloc = gicp_irq_domain_alloc,
149 .free = gicp_irq_domain_free,
150 };
151
152 static struct irq_chip gicp_msi_irq_chip = {
153 .name = "GICP",
154 .irq_set_type = irq_chip_set_type_parent,
155 .flags = IRQCHIP_SUPPORTS_LEVEL_MSI,
156 };
157
158 static struct msi_domain_ops gicp_msi_ops = {
159 };
160
161 static struct msi_domain_info gicp_msi_domain_info = {
162 .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
163 MSI_FLAG_LEVEL_CAPABLE),
164 .ops = &gicp_msi_ops,
165 .chip = &gicp_msi_irq_chip,
166 };
167
mvebu_gicp_probe(struct platform_device * pdev)168 static int mvebu_gicp_probe(struct platform_device *pdev)
169 {
170 struct mvebu_gicp *gicp;
171 struct irq_domain *inner_domain, *plat_domain, *parent_domain;
172 struct device_node *node = pdev->dev.of_node;
173 struct device_node *irq_parent_dn;
174 int ret, i;
175
176 gicp = devm_kzalloc(&pdev->dev, sizeof(*gicp), GFP_KERNEL);
177 if (!gicp)
178 return -ENOMEM;
179
180 gicp->dev = &pdev->dev;
181 spin_lock_init(&gicp->spi_lock);
182
183 gicp->res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
184 if (!gicp->res)
185 return -ENODEV;
186
187 ret = of_property_count_u32_elems(node, "marvell,spi-ranges");
188 if (ret < 0)
189 return ret;
190
191 gicp->spi_ranges_cnt = ret / 2;
192
193 gicp->spi_ranges =
194 devm_kcalloc(&pdev->dev,
195 gicp->spi_ranges_cnt,
196 sizeof(struct mvebu_gicp_spi_range),
197 GFP_KERNEL);
198 if (!gicp->spi_ranges)
199 return -ENOMEM;
200
201 for (i = 0; i < gicp->spi_ranges_cnt; i++) {
202 of_property_read_u32_index(node, "marvell,spi-ranges",
203 i * 2,
204 &gicp->spi_ranges[i].start);
205
206 of_property_read_u32_index(node, "marvell,spi-ranges",
207 i * 2 + 1,
208 &gicp->spi_ranges[i].count);
209
210 gicp->spi_cnt += gicp->spi_ranges[i].count;
211 }
212
213 gicp->spi_bitmap = devm_kcalloc(&pdev->dev,
214 BITS_TO_LONGS(gicp->spi_cnt), sizeof(long),
215 GFP_KERNEL);
216 if (!gicp->spi_bitmap)
217 return -ENOMEM;
218
219 irq_parent_dn = of_irq_find_parent(node);
220 if (!irq_parent_dn) {
221 dev_err(&pdev->dev, "failed to find parent IRQ node\n");
222 return -ENODEV;
223 }
224
225 parent_domain = irq_find_host(irq_parent_dn);
226 if (!parent_domain) {
227 dev_err(&pdev->dev, "failed to find parent IRQ domain\n");
228 return -ENODEV;
229 }
230
231 inner_domain = irq_domain_create_hierarchy(parent_domain, 0,
232 gicp->spi_cnt,
233 of_node_to_fwnode(node),
234 &gicp_domain_ops, gicp);
235 if (!inner_domain)
236 return -ENOMEM;
237
238
239 plat_domain = platform_msi_create_irq_domain(of_node_to_fwnode(node),
240 &gicp_msi_domain_info,
241 inner_domain);
242 if (!plat_domain) {
243 irq_domain_remove(inner_domain);
244 return -ENOMEM;
245 }
246
247 platform_set_drvdata(pdev, gicp);
248
249 return 0;
250 }
251
252 static const struct of_device_id mvebu_gicp_of_match[] = {
253 { .compatible = "marvell,ap806-gicp", },
254 {},
255 };
256
257 static struct platform_driver mvebu_gicp_driver = {
258 .probe = mvebu_gicp_probe,
259 .driver = {
260 .name = "mvebu-gicp",
261 .of_match_table = mvebu_gicp_of_match,
262 },
263 };
264 builtin_platform_driver(mvebu_gicp_driver);
265