xref: /openbmc/u-boot/arch/x86/cpu/irq.c (revision e30d2bd4)
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 #include <asm/tables.h>
17 
18 DECLARE_GLOBAL_DATA_PTR;
19 
20 bool pirq_check_irq_routed(struct udevice *dev, int link, u8 irq)
21 {
22 	struct irq_router *priv = dev_get_priv(dev);
23 	u8 pirq;
24 	int base = priv->link_base;
25 
26 	if (priv->config == PIRQ_VIA_PCI)
27 		dm_pci_read_config8(dev->parent, LINK_N2V(link, base), &pirq);
28 	else
29 		pirq = readb((uintptr_t)priv->ibase + LINK_N2V(link, base));
30 
31 	pirq &= 0xf;
32 
33 	/* IRQ# 0/1/2/8/13 are reserved */
34 	if (pirq < 3 || pirq == 8 || pirq == 13)
35 		return false;
36 
37 	return pirq == irq ? true : false;
38 }
39 
40 int pirq_translate_link(struct udevice *dev, int link)
41 {
42 	struct irq_router *priv = dev_get_priv(dev);
43 
44 	return LINK_V2N(link, priv->link_base);
45 }
46 
47 void pirq_assign_irq(struct udevice *dev, int link, u8 irq)
48 {
49 	struct irq_router *priv = dev_get_priv(dev);
50 	int base = priv->link_base;
51 
52 	/* IRQ# 0/1/2/8/13 are reserved */
53 	if (irq < 3 || irq == 8 || irq == 13)
54 		return;
55 
56 	if (priv->config == PIRQ_VIA_PCI)
57 		dm_pci_write_config8(dev->parent, LINK_N2V(link, base), irq);
58 	else
59 		writeb(irq, (uintptr_t)priv->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_router *priv, struct irq_info *slot,
78 				 int bus, int device, int pin, int pirq)
79 {
80 	slot->bus = bus;
81 	slot->devfn = (device << 3) | 0;
82 	slot->irq[pin - 1].link = LINK_N2V(pirq, priv->link_base);
83 	slot->irq[pin - 1].bitmap = priv->irq_mask;
84 }
85 
86 static int create_pirq_routing_table(struct udevice *dev)
87 {
88 	struct irq_router *priv = dev_get_priv(dev);
89 	const void *blob = gd->fdt_blob;
90 	int node;
91 	int len, count;
92 	const u32 *cell;
93 	struct irq_routing_table *rt;
94 	struct irq_info *slot, *slot_base;
95 	int irq_entries = 0;
96 	int i;
97 	int ret;
98 
99 	node = dev_of_offset(dev);
100 
101 	/* extract the bdf from fdt_pci_addr */
102 	priv->bdf = dm_pci_get_bdf(dev->parent);
103 
104 	ret = fdt_stringlist_search(blob, node, "intel,pirq-config", "pci");
105 	if (!ret) {
106 		priv->config = PIRQ_VIA_PCI;
107 	} else {
108 		ret = fdt_stringlist_search(blob, node, "intel,pirq-config",
109 					    "ibase");
110 		if (!ret)
111 			priv->config = PIRQ_VIA_IBASE;
112 		else
113 			return -EINVAL;
114 	}
115 
116 	ret = fdtdec_get_int(blob, node, "intel,pirq-link", -1);
117 	if (ret == -1)
118 		return ret;
119 	priv->link_base = ret;
120 
121 	priv->irq_mask = fdtdec_get_int(blob, node,
122 					"intel,pirq-mask", PIRQ_BITMAP);
123 
124 	if (IS_ENABLED(CONFIG_GENERATE_ACPI_TABLE)) {
125 		/* Reserve IRQ9 for SCI */
126 		priv->irq_mask &= ~(1 << 9);
127 	}
128 
129 	if (priv->config == PIRQ_VIA_IBASE) {
130 		int ibase_off;
131 
132 		ibase_off = fdtdec_get_int(blob, node, "intel,ibase-offset", 0);
133 		if (!ibase_off)
134 			return -EINVAL;
135 
136 		/*
137 		 * Here we assume that the IBASE register has already been
138 		 * properly configured by U-Boot before.
139 		 *
140 		 * By 'valid' we mean:
141 		 *   1) a valid memory space carved within system memory space
142 		 *      assigned to IBASE register block.
143 		 *   2) memory range decoding is enabled.
144 		 * Hence we don't do any santify test here.
145 		 */
146 		dm_pci_read_config32(dev->parent, ibase_off, &priv->ibase);
147 		priv->ibase &= ~0xf;
148 	}
149 
150 	priv->actl_8bit = fdtdec_get_bool(blob, node, "intel,actl-8bit");
151 	priv->actl_addr = fdtdec_get_int(blob, node, "intel,actl-addr", 0);
152 
153 	cell = fdt_getprop(blob, node, "intel,pirq-routing", &len);
154 	if (!cell || len % sizeof(struct pirq_routing))
155 		return -EINVAL;
156 	count = len / sizeof(struct pirq_routing);
157 
158 	rt = calloc(1, sizeof(struct irq_routing_table));
159 	if (!rt)
160 		return -ENOMEM;
161 
162 	/* Populate the PIRQ table fields */
163 	rt->signature = PIRQ_SIGNATURE;
164 	rt->version = PIRQ_VERSION;
165 	rt->rtr_bus = PCI_BUS(priv->bdf);
166 	rt->rtr_devfn = (PCI_DEV(priv->bdf) << 3) | PCI_FUNC(priv->bdf);
167 	rt->rtr_vendor = PCI_VENDOR_ID_INTEL;
168 	rt->rtr_device = PCI_DEVICE_ID_INTEL_ICH7_31;
169 
170 	slot_base = rt->slots;
171 
172 	/* Now fill in the irq_info entries in the PIRQ table */
173 	for (i = 0; i < count;
174 	     i++, cell += sizeof(struct pirq_routing) / sizeof(u32)) {
175 		struct pirq_routing pr;
176 
177 		pr.bdf = fdt_addr_to_cpu(cell[0]);
178 		pr.pin = fdt_addr_to_cpu(cell[1]);
179 		pr.pirq = fdt_addr_to_cpu(cell[2]);
180 
181 		debug("irq_info %d: b.d.f %x.%x.%x INT%c PIRQ%c\n",
182 		      i, PCI_BUS(pr.bdf), PCI_DEV(pr.bdf),
183 		      PCI_FUNC(pr.bdf), 'A' + pr.pin - 1,
184 		      'A' + pr.pirq);
185 
186 		slot = check_dup_entry(slot_base, irq_entries,
187 				       PCI_BUS(pr.bdf), PCI_DEV(pr.bdf));
188 		if (slot) {
189 			debug("found entry for bus %d device %d, ",
190 			      PCI_BUS(pr.bdf), PCI_DEV(pr.bdf));
191 
192 			if (slot->irq[pr.pin - 1].link) {
193 				debug("skipping\n");
194 
195 				/*
196 				 * Sanity test on the routed PIRQ pin
197 				 *
198 				 * If they don't match, show a warning to tell
199 				 * there might be something wrong with the PIRQ
200 				 * routing information in the device tree.
201 				 */
202 				if (slot->irq[pr.pin - 1].link !=
203 					LINK_N2V(pr.pirq, priv->link_base))
204 					debug("WARNING: Inconsistent PIRQ routing information\n");
205 				continue;
206 			}
207 		} else {
208 			slot = slot_base + irq_entries++;
209 		}
210 		debug("writing INT%c\n", 'A' + pr.pin - 1);
211 		fill_irq_info(priv, slot, PCI_BUS(pr.bdf), PCI_DEV(pr.bdf),
212 			      pr.pin, pr.pirq);
213 	}
214 
215 	rt->size = irq_entries * sizeof(struct irq_info) + 32;
216 
217 	/* Fix up the table checksum */
218 	rt->checksum = table_compute_checksum(rt, rt->size);
219 
220 	gd->arch.pirq_routing_table = rt;
221 
222 	return 0;
223 }
224 
225 static void irq_enable_sci(struct udevice *dev)
226 {
227 	struct irq_router *priv = dev_get_priv(dev);
228 
229 	if (priv->actl_8bit) {
230 		/* Bit7 must be turned on to enable ACPI */
231 		dm_pci_write_config8(dev->parent, priv->actl_addr, 0x80);
232 	} else {
233 		/* Write 0 to enable SCI on IRQ9 */
234 		if (priv->config == PIRQ_VIA_PCI)
235 			dm_pci_write_config32(dev->parent, priv->actl_addr, 0);
236 		else
237 			writel(0, (uintptr_t)priv->ibase + priv->actl_addr);
238 	}
239 }
240 
241 int irq_router_common_init(struct udevice *dev)
242 {
243 	int ret;
244 
245 	ret = create_pirq_routing_table(dev);
246 	if (ret) {
247 		debug("Failed to create pirq routing table\n");
248 		return ret;
249 	}
250 	/* Route PIRQ */
251 	pirq_route_irqs(dev, gd->arch.pirq_routing_table->slots,
252 			get_irq_slot_count(gd->arch.pirq_routing_table));
253 
254 	if (IS_ENABLED(CONFIG_GENERATE_ACPI_TABLE))
255 		irq_enable_sci(dev);
256 
257 	return 0;
258 }
259 
260 int irq_router_probe(struct udevice *dev)
261 {
262 	return irq_router_common_init(dev);
263 }
264 
265 ulong write_pirq_routing_table(ulong addr)
266 {
267 	if (!gd->arch.pirq_routing_table)
268 		return addr;
269 
270 	return copy_pirq_routing_table(addr, gd->arch.pirq_routing_table);
271 }
272 
273 static const struct udevice_id irq_router_ids[] = {
274 	{ .compatible = "intel,irq-router" },
275 	{ }
276 };
277 
278 U_BOOT_DRIVER(irq_router_drv) = {
279 	.name		= "intel_irq",
280 	.id		= UCLASS_IRQ,
281 	.of_match	= irq_router_ids,
282 	.probe		= irq_router_probe,
283 	.priv_auto_alloc_size = sizeof(struct irq_router),
284 };
285 
286 UCLASS_DRIVER(irq) = {
287 	.id		= UCLASS_IRQ,
288 	.name		= "irq",
289 };
290