xref: /rk3399_rockchip-uboot/arch/x86/cpu/irq.c (revision 12d6929e1f70da7bdbd7ac1de3db33fdff50a716)
1 /*
2  * Copyright (C) 2015, Bin Meng <bmeng.cn@gmail.com>
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 #include <common.h>
8 #include <dm.h>
9 #include <errno.h>
10 #include <fdtdec.h>
11 #include <malloc.h>
12 #include <asm/io.h>
13 #include <asm/irq.h>
14 #include <asm/pci.h>
15 #include <asm/pirq_routing.h>
16 
17 DECLARE_GLOBAL_DATA_PTR;
18 
19 static struct irq_router irq_router;
20 static struct irq_routing_table *pirq_routing_table;
21 
22 bool pirq_check_irq_routed(int link, u8 irq)
23 {
24 	u8 pirq;
25 	int base = irq_router.link_base;
26 
27 	if (irq_router.config == PIRQ_VIA_PCI)
28 		pirq = x86_pci_read_config8(irq_router.bdf,
29 					    LINK_N2V(link, base));
30 	else
31 		pirq = readb(irq_router.ibase + LINK_N2V(link, base));
32 
33 	pirq &= 0xf;
34 
35 	/* IRQ# 0/1/2/8/13 are reserved */
36 	if (pirq < 3 || pirq == 8 || pirq == 13)
37 		return false;
38 
39 	return pirq == irq ? true : false;
40 }
41 
42 int pirq_translate_link(int link)
43 {
44 	return LINK_V2N(link, irq_router.link_base);
45 }
46 
47 void pirq_assign_irq(int link, u8 irq)
48 {
49 	int base = irq_router.link_base;
50 
51 	/* IRQ# 0/1/2/8/13 are reserved */
52 	if (irq < 3 || irq == 8 || irq == 13)
53 		return;
54 
55 	if (irq_router.config == PIRQ_VIA_PCI)
56 		x86_pci_write_config8(irq_router.bdf,
57 				      LINK_N2V(link, base), irq);
58 	else
59 		writeb(irq, irq_router.ibase + LINK_N2V(link, base));
60 }
61 
62 static struct irq_info *check_dup_entry(struct irq_info *slot_base,
63 					int entry_num, int bus, int device)
64 {
65 	struct irq_info *slot = slot_base;
66 	int i;
67 
68 	for (i = 0; i < entry_num; i++) {
69 		if (slot->bus == bus && slot->devfn == (device << 3))
70 			break;
71 		slot++;
72 	}
73 
74 	return (i == entry_num) ? NULL : slot;
75 }
76 
77 static inline void fill_irq_info(struct irq_info *slot, int bus, int device,
78 				 int pin, int pirq)
79 {
80 	slot->bus = bus;
81 	slot->devfn = (device << 3) | 0;
82 	slot->irq[pin - 1].link = LINK_N2V(pirq, irq_router.link_base);
83 	slot->irq[pin - 1].bitmap = irq_router.irq_mask;
84 }
85 
86 __weak void cpu_irq_init(void)
87 {
88 	return;
89 }
90 
91 static int create_pirq_routing_table(void)
92 {
93 	const void *blob = gd->fdt_blob;
94 	struct fdt_pci_addr addr;
95 	int node;
96 	int len, count;
97 	const u32 *cell;
98 	struct irq_routing_table *rt;
99 	struct irq_info *slot, *slot_base;
100 	int irq_entries = 0;
101 	int parent;
102 	int i;
103 	int ret;
104 
105 	node = fdtdec_next_compatible(blob, 0, COMPAT_INTEL_IRQ_ROUTER);
106 	if (node < 0) {
107 		debug("%s: Cannot find irq router node\n", __func__);
108 		return -EINVAL;
109 	}
110 
111 	/* TODO(sjg@chromium.org): Drop this when PIRQ is a driver */
112 	parent = fdt_parent_offset(blob, node);
113 	if (parent < 0)
114 		return -EINVAL;
115 	ret = fdtdec_get_pci_addr(blob, parent, FDT_PCI_SPACE_CONFIG,
116 				  "reg", &addr);
117 	if (ret)
118 		return ret;
119 
120 	/* extract the bdf from fdt_pci_addr */
121 	irq_router.bdf = addr.phys_hi & 0xffff00;
122 
123 	ret = fdt_find_string(blob, node, "intel,pirq-config", "pci");
124 	if (!ret) {
125 		irq_router.config = PIRQ_VIA_PCI;
126 	} else {
127 		ret = fdt_find_string(blob, node, "intel,pirq-config", "ibase");
128 		if (!ret)
129 			irq_router.config = PIRQ_VIA_IBASE;
130 		else
131 			return -EINVAL;
132 	}
133 
134 	ret = fdtdec_get_int(blob, node, "intel,pirq-link", -1);
135 	if (ret == -1)
136 		return ret;
137 	irq_router.link_base = ret;
138 
139 	irq_router.irq_mask = fdtdec_get_int(blob, node,
140 					     "intel,pirq-mask", PIRQ_BITMAP);
141 
142 	if (irq_router.config == PIRQ_VIA_IBASE) {
143 		int ibase_off;
144 
145 		ibase_off = fdtdec_get_int(blob, node, "intel,ibase-offset", 0);
146 		if (!ibase_off)
147 			return -EINVAL;
148 
149 		/*
150 		 * Here we assume that the IBASE register has already been
151 		 * properly configured by U-Boot before.
152 		 *
153 		 * By 'valid' we mean:
154 		 *   1) a valid memory space carved within system memory space
155 		 *      assigned to IBASE register block.
156 		 *   2) memory range decoding is enabled.
157 		 * Hence we don't do any santify test here.
158 		 */
159 		irq_router.ibase = x86_pci_read_config32(irq_router.bdf,
160 							 ibase_off);
161 		irq_router.ibase &= ~0xf;
162 	}
163 
164 	cell = fdt_getprop(blob, node, "intel,pirq-routing", &len);
165 	if (!cell || len % sizeof(struct pirq_routing))
166 		return -EINVAL;
167 	count = len / sizeof(struct pirq_routing);
168 
169 	rt = calloc(1, sizeof(struct irq_routing_table));
170 	if (!rt)
171 		return -ENOMEM;
172 
173 	/* Populate the PIRQ table fields */
174 	rt->signature = PIRQ_SIGNATURE;
175 	rt->version = PIRQ_VERSION;
176 	rt->rtr_bus = PCI_BUS(irq_router.bdf);
177 	rt->rtr_devfn = (PCI_DEV(irq_router.bdf) << 3) |
178 			PCI_FUNC(irq_router.bdf);
179 	rt->rtr_vendor = PCI_VENDOR_ID_INTEL;
180 	rt->rtr_device = PCI_DEVICE_ID_INTEL_ICH7_31;
181 
182 	slot_base = rt->slots;
183 
184 	/* Now fill in the irq_info entries in the PIRQ table */
185 	for (i = 0; i < count;
186 	     i++, cell += sizeof(struct pirq_routing) / sizeof(u32)) {
187 		struct pirq_routing pr;
188 
189 		pr.bdf = fdt_addr_to_cpu(cell[0]);
190 		pr.pin = fdt_addr_to_cpu(cell[1]);
191 		pr.pirq = fdt_addr_to_cpu(cell[2]);
192 
193 		debug("irq_info %d: b.d.f %x.%x.%x INT%c PIRQ%c\n",
194 		      i, PCI_BUS(pr.bdf), PCI_DEV(pr.bdf),
195 		      PCI_FUNC(pr.bdf), 'A' + pr.pin - 1,
196 		      'A' + pr.pirq);
197 
198 		slot = check_dup_entry(slot_base, irq_entries,
199 				       PCI_BUS(pr.bdf), PCI_DEV(pr.bdf));
200 		if (slot) {
201 			debug("found entry for bus %d device %d, ",
202 			      PCI_BUS(pr.bdf), PCI_DEV(pr.bdf));
203 
204 			if (slot->irq[pr.pin - 1].link) {
205 				debug("skipping\n");
206 
207 				/*
208 				 * Sanity test on the routed PIRQ pin
209 				 *
210 				 * If they don't match, show a warning to tell
211 				 * there might be something wrong with the PIRQ
212 				 * routing information in the device tree.
213 				 */
214 				if (slot->irq[pr.pin - 1].link !=
215 					LINK_N2V(pr.pirq, irq_router.link_base))
216 					debug("WARNING: Inconsistent PIRQ routing information\n");
217 				continue;
218 			}
219 		} else {
220 			slot = slot_base + irq_entries++;
221 		}
222 		debug("writing INT%c\n", 'A' + pr.pin - 1);
223 		fill_irq_info(slot, PCI_BUS(pr.bdf), PCI_DEV(pr.bdf), pr.pin,
224 			      pr.pirq);
225 	}
226 
227 	rt->size = irq_entries * sizeof(struct irq_info) + 32;
228 
229 	pirq_routing_table = rt;
230 
231 	return 0;
232 }
233 
234 int irq_router_probe(struct udevice *dev)
235 {
236 	int ret;
237 
238 	cpu_irq_init();
239 
240 	ret = create_pirq_routing_table();
241 	if (ret) {
242 		debug("Failed to create pirq routing table\n");
243 		return ret;
244 	}
245 	/* Route PIRQ */
246 	pirq_route_irqs(pirq_routing_table->slots,
247 			get_irq_slot_count(pirq_routing_table));
248 
249 	return 0;
250 }
251 
252 u32 write_pirq_routing_table(u32 addr)
253 {
254 	if (!pirq_routing_table)
255 		return addr;
256 
257 	return copy_pirq_routing_table(addr, pirq_routing_table);
258 }
259 
260 static const struct udevice_id irq_router_ids[] = {
261 	{ .compatible = "intel,irq-router" },
262 	{ }
263 };
264 
265 U_BOOT_DRIVER(irq_router_drv) = {
266 	.name		= "intel_irq",
267 	.id		= UCLASS_IRQ,
268 	.of_match	= irq_router_ids,
269 	.probe		= irq_router_probe,
270 };
271 
272 UCLASS_DRIVER(irq) = {
273 	.id		= UCLASS_IRQ,
274 	.name		= "irq",
275 };
276