xref: /openbmc/u-boot/arch/x86/cpu/irq.c (revision 7da7ff54)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2015, Bin Meng <bmeng.cn@gmail.com>
4  */
5 
6 #include <common.h>
7 #include <dm.h>
8 #include <errno.h>
9 #include <fdtdec.h>
10 #include <malloc.h>
11 #include <asm/io.h>
12 #include <asm/irq.h>
13 #include <asm/pci.h>
14 #include <asm/pirq_routing.h>
15 #include <asm/tables.h>
16 
17 DECLARE_GLOBAL_DATA_PTR;
18 
19 /**
20  * pirq_reg_to_linkno() - Convert a PIRQ routing register offset to link number
21  *
22  * @priv:	IRQ router driver's priv data
23  * @reg:	PIRQ routing register offset from the base address
24  * @return:	PIRQ link number (0 for PIRQA, 1 for PIRQB, etc)
25  */
26 static inline int pirq_reg_to_linkno(struct irq_router *priv, int reg)
27 {
28 	int linkno = 0;
29 
30 	if (priv->has_regmap) {
31 		struct pirq_regmap *map = priv->regmap;
32 		int i;
33 
34 		for (i = 0; i < priv->link_num; i++) {
35 			if (reg - priv->link_base == map->offset) {
36 				linkno = map->link;
37 				break;
38 			}
39 			map++;
40 		}
41 	} else {
42 		linkno = reg - priv->link_base;
43 	}
44 
45 	return linkno;
46 }
47 
48 /**
49  * pirq_linkno_to_reg() - Convert a PIRQ link number to routing register offset
50  *
51  * @priv:	IRQ router driver's priv data
52  * @linkno:	PIRQ link number (0 for PIRQA, 1 for PIRQB, etc)
53  * @return:	PIRQ routing register offset from the base address
54  */
55 static inline int pirq_linkno_to_reg(struct irq_router *priv, int linkno)
56 {
57 	int reg = 0;
58 
59 	if (priv->has_regmap) {
60 		struct pirq_regmap *map = priv->regmap;
61 		int i;
62 
63 		for (i = 0; i < priv->link_num; i++) {
64 			if (linkno == map->link) {
65 				reg = map->offset + priv->link_base;
66 				break;
67 			}
68 			map++;
69 		}
70 	} else {
71 		reg = linkno + priv->link_base;
72 	}
73 
74 	return reg;
75 }
76 
77 bool pirq_check_irq_routed(struct udevice *dev, int link, u8 irq)
78 {
79 	struct irq_router *priv = dev_get_priv(dev);
80 	u8 pirq;
81 
82 	if (priv->config == PIRQ_VIA_PCI)
83 		dm_pci_read_config8(dev->parent,
84 				    pirq_linkno_to_reg(priv, link), &pirq);
85 	else
86 		pirq = readb((uintptr_t)priv->ibase +
87 			     pirq_linkno_to_reg(priv, link));
88 
89 	pirq &= 0xf;
90 
91 	/* IRQ# 0/1/2/8/13 are reserved */
92 	if (pirq < 3 || pirq == 8 || pirq == 13)
93 		return false;
94 
95 	return pirq == irq ? true : false;
96 }
97 
98 int pirq_translate_link(struct udevice *dev, int link)
99 {
100 	struct irq_router *priv = dev_get_priv(dev);
101 
102 	return pirq_reg_to_linkno(priv, link);
103 }
104 
105 void pirq_assign_irq(struct udevice *dev, int link, u8 irq)
106 {
107 	struct irq_router *priv = dev_get_priv(dev);
108 
109 	/* IRQ# 0/1/2/8/13 are reserved */
110 	if (irq < 3 || irq == 8 || irq == 13)
111 		return;
112 
113 	if (priv->config == PIRQ_VIA_PCI)
114 		dm_pci_write_config8(dev->parent,
115 				     pirq_linkno_to_reg(priv, link), irq);
116 	else
117 		writeb(irq, (uintptr_t)priv->ibase +
118 		       pirq_linkno_to_reg(priv, link));
119 }
120 
121 static struct irq_info *check_dup_entry(struct irq_info *slot_base,
122 					int entry_num, int bus, int device)
123 {
124 	struct irq_info *slot = slot_base;
125 	int i;
126 
127 	for (i = 0; i < entry_num; i++) {
128 		if (slot->bus == bus && slot->devfn == (device << 3))
129 			break;
130 		slot++;
131 	}
132 
133 	return (i == entry_num) ? NULL : slot;
134 }
135 
136 static inline void fill_irq_info(struct irq_router *priv, struct irq_info *slot,
137 				 int bus, int device, int pin, int pirq)
138 {
139 	slot->bus = bus;
140 	slot->devfn = (device << 3) | 0;
141 	slot->irq[pin - 1].link = pirq_linkno_to_reg(priv, pirq);
142 	slot->irq[pin - 1].bitmap = priv->irq_mask;
143 }
144 
145 static int create_pirq_routing_table(struct udevice *dev)
146 {
147 	struct irq_router *priv = dev_get_priv(dev);
148 	const void *blob = gd->fdt_blob;
149 	int node;
150 	int len, count;
151 	const u32 *cell;
152 	struct pirq_regmap *map;
153 	struct irq_routing_table *rt;
154 	struct irq_info *slot, *slot_base;
155 	int irq_entries = 0;
156 	int i;
157 	int ret;
158 
159 	node = dev_of_offset(dev);
160 
161 	/* extract the bdf from fdt_pci_addr */
162 	priv->bdf = dm_pci_get_bdf(dev->parent);
163 
164 	ret = fdt_stringlist_search(blob, node, "intel,pirq-config", "pci");
165 	if (!ret) {
166 		priv->config = PIRQ_VIA_PCI;
167 	} else {
168 		ret = fdt_stringlist_search(blob, node, "intel,pirq-config",
169 					    "ibase");
170 		if (!ret)
171 			priv->config = PIRQ_VIA_IBASE;
172 		else
173 			return -EINVAL;
174 	}
175 
176 	cell = fdt_getprop(blob, node, "intel,pirq-link", &len);
177 	if (!cell || len != 8)
178 		return -EINVAL;
179 	priv->link_base = fdt_addr_to_cpu(cell[0]);
180 	priv->link_num = fdt_addr_to_cpu(cell[1]);
181 	if (priv->link_num > CONFIG_MAX_PIRQ_LINKS) {
182 		debug("Limiting supported PIRQ link number from %d to %d\n",
183 		      priv->link_num, CONFIG_MAX_PIRQ_LINKS);
184 		priv->link_num = CONFIG_MAX_PIRQ_LINKS;
185 	}
186 
187 	cell = fdt_getprop(blob, node, "intel,pirq-regmap", &len);
188 	if (cell) {
189 		if (len % sizeof(struct pirq_regmap))
190 			return -EINVAL;
191 
192 		count = len / sizeof(struct pirq_regmap);
193 		if (count < priv->link_num) {
194 			printf("Number of pirq-regmap entires is wrong\n");
195 			return -EINVAL;
196 		}
197 
198 		count = priv->link_num;
199 		priv->regmap = calloc(count, sizeof(struct pirq_regmap));
200 		if (!priv->regmap)
201 			return -ENOMEM;
202 
203 		priv->has_regmap = true;
204 		map = priv->regmap;
205 		for (i = 0; i < count; i++) {
206 			map->link = fdt_addr_to_cpu(cell[0]);
207 			map->offset = fdt_addr_to_cpu(cell[1]);
208 
209 			cell += sizeof(struct pirq_regmap) / sizeof(u32);
210 			map++;
211 		}
212 	}
213 
214 	priv->irq_mask = fdtdec_get_int(blob, node,
215 					"intel,pirq-mask", PIRQ_BITMAP);
216 
217 	if (IS_ENABLED(CONFIG_GENERATE_ACPI_TABLE)) {
218 		/* Reserve IRQ9 for SCI */
219 		priv->irq_mask &= ~(1 << 9);
220 	}
221 
222 	if (priv->config == PIRQ_VIA_IBASE) {
223 		int ibase_off;
224 
225 		ibase_off = fdtdec_get_int(blob, node, "intel,ibase-offset", 0);
226 		if (!ibase_off)
227 			return -EINVAL;
228 
229 		/*
230 		 * Here we assume that the IBASE register has already been
231 		 * properly configured by U-Boot before.
232 		 *
233 		 * By 'valid' we mean:
234 		 *   1) a valid memory space carved within system memory space
235 		 *      assigned to IBASE register block.
236 		 *   2) memory range decoding is enabled.
237 		 * Hence we don't do any santify test here.
238 		 */
239 		dm_pci_read_config32(dev->parent, ibase_off, &priv->ibase);
240 		priv->ibase &= ~0xf;
241 	}
242 
243 	priv->actl_8bit = fdtdec_get_bool(blob, node, "intel,actl-8bit");
244 	priv->actl_addr = fdtdec_get_int(blob, node, "intel,actl-addr", 0);
245 
246 	cell = fdt_getprop(blob, node, "intel,pirq-routing", &len);
247 	if (!cell || len % sizeof(struct pirq_routing))
248 		return -EINVAL;
249 	count = len / sizeof(struct pirq_routing);
250 
251 	rt = calloc(1, sizeof(struct irq_routing_table));
252 	if (!rt)
253 		return -ENOMEM;
254 
255 	/* Populate the PIRQ table fields */
256 	rt->signature = PIRQ_SIGNATURE;
257 	rt->version = PIRQ_VERSION;
258 	rt->rtr_bus = PCI_BUS(priv->bdf);
259 	rt->rtr_devfn = (PCI_DEV(priv->bdf) << 3) | PCI_FUNC(priv->bdf);
260 	rt->rtr_vendor = PCI_VENDOR_ID_INTEL;
261 	rt->rtr_device = PCI_DEVICE_ID_INTEL_ICH7_31;
262 
263 	slot_base = rt->slots;
264 
265 	/* Now fill in the irq_info entries in the PIRQ table */
266 	for (i = 0; i < count;
267 	     i++, cell += sizeof(struct pirq_routing) / sizeof(u32)) {
268 		struct pirq_routing pr;
269 
270 		pr.bdf = fdt_addr_to_cpu(cell[0]);
271 		pr.pin = fdt_addr_to_cpu(cell[1]);
272 		pr.pirq = fdt_addr_to_cpu(cell[2]);
273 
274 		debug("irq_info %d: b.d.f %x.%x.%x INT%c PIRQ%c\n",
275 		      i, PCI_BUS(pr.bdf), PCI_DEV(pr.bdf),
276 		      PCI_FUNC(pr.bdf), 'A' + pr.pin - 1,
277 		      'A' + pr.pirq);
278 
279 		slot = check_dup_entry(slot_base, irq_entries,
280 				       PCI_BUS(pr.bdf), PCI_DEV(pr.bdf));
281 		if (slot) {
282 			debug("found entry for bus %d device %d, ",
283 			      PCI_BUS(pr.bdf), PCI_DEV(pr.bdf));
284 
285 			if (slot->irq[pr.pin - 1].link) {
286 				debug("skipping\n");
287 
288 				/*
289 				 * Sanity test on the routed PIRQ pin
290 				 *
291 				 * If they don't match, show a warning to tell
292 				 * there might be something wrong with the PIRQ
293 				 * routing information in the device tree.
294 				 */
295 				if (slot->irq[pr.pin - 1].link !=
296 				    pirq_linkno_to_reg(priv, pr.pirq))
297 					debug("WARNING: Inconsistent PIRQ routing information\n");
298 				continue;
299 			}
300 		} else {
301 			slot = slot_base + irq_entries++;
302 		}
303 		debug("writing INT%c\n", 'A' + pr.pin - 1);
304 		fill_irq_info(priv, slot, PCI_BUS(pr.bdf), PCI_DEV(pr.bdf),
305 			      pr.pin, pr.pirq);
306 	}
307 
308 	rt->size = irq_entries * sizeof(struct irq_info) + 32;
309 
310 	/* Fix up the table checksum */
311 	rt->checksum = table_compute_checksum(rt, rt->size);
312 
313 	gd->arch.pirq_routing_table = rt;
314 
315 	return 0;
316 }
317 
318 static void irq_enable_sci(struct udevice *dev)
319 {
320 	struct irq_router *priv = dev_get_priv(dev);
321 
322 	if (priv->actl_8bit) {
323 		/* Bit7 must be turned on to enable ACPI */
324 		dm_pci_write_config8(dev->parent, priv->actl_addr, 0x80);
325 	} else {
326 		/* Write 0 to enable SCI on IRQ9 */
327 		if (priv->config == PIRQ_VIA_PCI)
328 			dm_pci_write_config32(dev->parent, priv->actl_addr, 0);
329 		else
330 			writel(0, (uintptr_t)priv->ibase + priv->actl_addr);
331 	}
332 }
333 
334 int irq_router_probe(struct udevice *dev)
335 {
336 	int ret;
337 
338 	ret = create_pirq_routing_table(dev);
339 	if (ret) {
340 		debug("Failed to create pirq routing table\n");
341 		return ret;
342 	}
343 	/* Route PIRQ */
344 	pirq_route_irqs(dev, gd->arch.pirq_routing_table->slots,
345 			get_irq_slot_count(gd->arch.pirq_routing_table));
346 
347 	if (IS_ENABLED(CONFIG_GENERATE_ACPI_TABLE))
348 		irq_enable_sci(dev);
349 
350 	return 0;
351 }
352 
353 ulong write_pirq_routing_table(ulong addr)
354 {
355 	if (!gd->arch.pirq_routing_table)
356 		return addr;
357 
358 	return copy_pirq_routing_table(addr, gd->arch.pirq_routing_table);
359 }
360 
361 static const struct udevice_id irq_router_ids[] = {
362 	{ .compatible = "intel,irq-router" },
363 	{ }
364 };
365 
366 U_BOOT_DRIVER(irq_router_drv) = {
367 	.name		= "intel_irq",
368 	.id		= UCLASS_IRQ,
369 	.of_match	= irq_router_ids,
370 	.probe		= irq_router_probe,
371 	.priv_auto_alloc_size = sizeof(struct irq_router),
372 };
373 
374 UCLASS_DRIVER(irq) = {
375 	.id		= UCLASS_IRQ,
376 	.name		= "irq",
377 };
378