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 <irq.h>
11 #include <log.h>
12 #include <malloc.h>
13 #include <asm/global_data.h>
14 #include <asm/io.h>
15 #include <asm/irq.h>
16 #include <asm/pci.h>
17 #include <asm/pirq_routing.h>
18 #include <asm/tables.h>
19 
20 DECLARE_GLOBAL_DATA_PTR;
21 
22 /**
23  * pirq_reg_to_linkno() - Convert a PIRQ routing register offset to link number
24  *
25  * @priv:	IRQ router driver's priv data
26  * @reg:	PIRQ routing register offset from the base address
27  * @return:	PIRQ link number (0 for PIRQA, 1 for PIRQB, etc)
28  */
pirq_reg_to_linkno(struct irq_router * priv,int reg)29 static inline int pirq_reg_to_linkno(struct irq_router *priv, int reg)
30 {
31 	int linkno = 0;
32 
33 	if (priv->has_regmap) {
34 		struct pirq_regmap *map = priv->regmap;
35 		int i;
36 
37 		for (i = 0; i < priv->link_num; i++) {
38 			if (reg - priv->link_base == map->offset) {
39 				linkno = map->link;
40 				break;
41 			}
42 			map++;
43 		}
44 	} else {
45 		linkno = reg - priv->link_base;
46 	}
47 
48 	return linkno;
49 }
50 
51 /**
52  * pirq_linkno_to_reg() - Convert a PIRQ link number to routing register offset
53  *
54  * @priv:	IRQ router driver's priv data
55  * @linkno:	PIRQ link number (0 for PIRQA, 1 for PIRQB, etc)
56  * @return:	PIRQ routing register offset from the base address
57  */
pirq_linkno_to_reg(struct irq_router * priv,int linkno)58 static inline int pirq_linkno_to_reg(struct irq_router *priv, int linkno)
59 {
60 	int reg = 0;
61 
62 	if (priv->has_regmap) {
63 		struct pirq_regmap *map = priv->regmap;
64 		int i;
65 
66 		for (i = 0; i < priv->link_num; i++) {
67 			if (linkno == map->link) {
68 				reg = map->offset + priv->link_base;
69 				break;
70 			}
71 			map++;
72 		}
73 	} else {
74 		reg = linkno + priv->link_base;
75 	}
76 
77 	return reg;
78 }
79 
pirq_check_irq_routed(struct udevice * dev,int link,u8 irq)80 bool pirq_check_irq_routed(struct udevice *dev, int link, u8 irq)
81 {
82 	struct irq_router *priv = dev_get_priv(dev);
83 	u8 pirq;
84 
85 	if (priv->config == PIRQ_VIA_PCI)
86 		dm_pci_read_config8(dev->parent,
87 				    pirq_linkno_to_reg(priv, link), &pirq);
88 	else
89 		pirq = readb((uintptr_t)priv->ibase +
90 			     pirq_linkno_to_reg(priv, link));
91 
92 	pirq &= 0xf;
93 
94 	/* IRQ# 0/1/2/8/13 are reserved */
95 	if (pirq < 3 || pirq == 8 || pirq == 13)
96 		return false;
97 
98 	return pirq == irq ? true : false;
99 }
100 
pirq_translate_link(struct udevice * dev,int link)101 int pirq_translate_link(struct udevice *dev, int link)
102 {
103 	struct irq_router *priv = dev_get_priv(dev);
104 
105 	return pirq_reg_to_linkno(priv, link);
106 }
107 
pirq_assign_irq(struct udevice * dev,int link,u8 irq)108 void pirq_assign_irq(struct udevice *dev, int link, u8 irq)
109 {
110 	struct irq_router *priv = dev_get_priv(dev);
111 
112 	/* IRQ# 0/1/2/8/13 are reserved */
113 	if (irq < 3 || irq == 8 || irq == 13)
114 		return;
115 
116 	if (priv->config == PIRQ_VIA_PCI)
117 		dm_pci_write_config8(dev->parent,
118 				     pirq_linkno_to_reg(priv, link), irq);
119 	else
120 		writeb(irq, (uintptr_t)priv->ibase +
121 		       pirq_linkno_to_reg(priv, link));
122 }
123 
check_dup_entry(struct irq_info * slot_base,int entry_num,int bus,int device)124 static struct irq_info *check_dup_entry(struct irq_info *slot_base,
125 					int entry_num, int bus, int device)
126 {
127 	struct irq_info *slot = slot_base;
128 	int i;
129 
130 	for (i = 0; i < entry_num; i++) {
131 		if (slot->bus == bus && slot->devfn == (device << 3))
132 			break;
133 		slot++;
134 	}
135 
136 	return (i == entry_num) ? NULL : slot;
137 }
138 
fill_irq_info(struct irq_router * priv,struct irq_info * slot,int bus,int device,int pin,int pirq)139 static inline void fill_irq_info(struct irq_router *priv, struct irq_info *slot,
140 				 int bus, int device, int pin, int pirq)
141 {
142 	slot->bus = bus;
143 	slot->devfn = (device << 3) | 0;
144 	slot->irq[pin - 1].link = pirq_linkno_to_reg(priv, pirq);
145 	slot->irq[pin - 1].bitmap = priv->irq_mask;
146 }
147 
create_pirq_routing_table(struct udevice * dev)148 static int create_pirq_routing_table(struct udevice *dev)
149 {
150 	struct irq_router *priv = dev_get_priv(dev);
151 	const void *blob = gd->fdt_blob;
152 	int node;
153 	int len, count;
154 	const u32 *cell;
155 	struct pirq_regmap *map;
156 	struct irq_routing_table *rt;
157 	struct irq_info *slot, *slot_base;
158 	int irq_entries = 0;
159 	int i;
160 	int ret;
161 
162 	node = dev_of_offset(dev);
163 
164 	/* extract the bdf from fdt_pci_addr */
165 	priv->bdf = dm_pci_get_bdf(dev->parent);
166 
167 	ret = fdt_stringlist_search(blob, node, "intel,pirq-config", "pci");
168 	if (!ret) {
169 		priv->config = PIRQ_VIA_PCI;
170 	} else {
171 		ret = fdt_stringlist_search(blob, node, "intel,pirq-config",
172 					    "ibase");
173 		if (!ret)
174 			priv->config = PIRQ_VIA_IBASE;
175 		else
176 			return -EINVAL;
177 	}
178 
179 	cell = fdt_getprop(blob, node, "intel,pirq-link", &len);
180 	if (!cell || len != 8)
181 		return -EINVAL;
182 	priv->link_base = fdt_addr_to_cpu(cell[0]);
183 	priv->link_num = fdt_addr_to_cpu(cell[1]);
184 	if (priv->link_num > CONFIG_MAX_PIRQ_LINKS) {
185 		debug("Limiting supported PIRQ link number from %d to %d\n",
186 		      priv->link_num, CONFIG_MAX_PIRQ_LINKS);
187 		priv->link_num = CONFIG_MAX_PIRQ_LINKS;
188 	}
189 
190 	cell = fdt_getprop(blob, node, "intel,pirq-regmap", &len);
191 	if (cell) {
192 		if (len % sizeof(struct pirq_regmap))
193 			return -EINVAL;
194 
195 		count = len / sizeof(struct pirq_regmap);
196 		if (count < priv->link_num) {
197 			printf("Number of pirq-regmap entires is wrong\n");
198 			return -EINVAL;
199 		}
200 
201 		count = priv->link_num;
202 		priv->regmap = calloc(count, sizeof(struct pirq_regmap));
203 		if (!priv->regmap)
204 			return -ENOMEM;
205 
206 		priv->has_regmap = true;
207 		map = priv->regmap;
208 		for (i = 0; i < count; i++) {
209 			map->link = fdt_addr_to_cpu(cell[0]);
210 			map->offset = fdt_addr_to_cpu(cell[1]);
211 
212 			cell += sizeof(struct pirq_regmap) / sizeof(u32);
213 			map++;
214 		}
215 	}
216 
217 	priv->irq_mask = fdtdec_get_int(blob, node,
218 					"intel,pirq-mask", PIRQ_BITMAP);
219 
220 	if (IS_ENABLED(CONFIG_GENERATE_ACPI_TABLE)) {
221 		/* Reserve IRQ9 for SCI */
222 		priv->irq_mask &= ~(1 << 9);
223 	}
224 
225 	if (priv->config == PIRQ_VIA_IBASE) {
226 		int ibase_off;
227 
228 		ibase_off = fdtdec_get_int(blob, node, "intel,ibase-offset", 0);
229 		if (!ibase_off)
230 			return -EINVAL;
231 
232 		/*
233 		 * Here we assume that the IBASE register has already been
234 		 * properly configured by U-Boot before.
235 		 *
236 		 * By 'valid' we mean:
237 		 *   1) a valid memory space carved within system memory space
238 		 *      assigned to IBASE register block.
239 		 *   2) memory range decoding is enabled.
240 		 * Hence we don't do any santify test here.
241 		 */
242 		dm_pci_read_config32(dev->parent, ibase_off, &priv->ibase);
243 		priv->ibase &= ~0xf;
244 	}
245 
246 	priv->actl_8bit = fdtdec_get_bool(blob, node, "intel,actl-8bit");
247 	priv->actl_addr = fdtdec_get_int(blob, node, "intel,actl-addr", 0);
248 
249 	cell = fdt_getprop(blob, node, "intel,pirq-routing", &len);
250 	if (!cell || len % sizeof(struct pirq_routing))
251 		return -EINVAL;
252 	count = len / sizeof(struct pirq_routing);
253 
254 	rt = calloc(1, sizeof(struct irq_routing_table));
255 	if (!rt)
256 		return -ENOMEM;
257 
258 	/* Populate the PIRQ table fields */
259 	rt->signature = PIRQ_SIGNATURE;
260 	rt->version = PIRQ_VERSION;
261 	rt->rtr_bus = PCI_BUS(priv->bdf);
262 	rt->rtr_devfn = (PCI_DEV(priv->bdf) << 3) | PCI_FUNC(priv->bdf);
263 	rt->rtr_vendor = PCI_VENDOR_ID_INTEL;
264 	rt->rtr_device = PCI_DEVICE_ID_INTEL_ICH7_31;
265 
266 	slot_base = rt->slots;
267 
268 	/* Now fill in the irq_info entries in the PIRQ table */
269 	for (i = 0; i < count;
270 	     i++, cell += sizeof(struct pirq_routing) / sizeof(u32)) {
271 		struct pirq_routing pr;
272 
273 		pr.bdf = fdt_addr_to_cpu(cell[0]);
274 		pr.pin = fdt_addr_to_cpu(cell[1]);
275 		pr.pirq = fdt_addr_to_cpu(cell[2]);
276 
277 		debug("irq_info %d: b.d.f %x.%x.%x INT%c PIRQ%c\n",
278 		      i, PCI_BUS(pr.bdf), PCI_DEV(pr.bdf),
279 		      PCI_FUNC(pr.bdf), 'A' + pr.pin - 1,
280 		      'A' + pr.pirq);
281 
282 		slot = check_dup_entry(slot_base, irq_entries,
283 				       PCI_BUS(pr.bdf), PCI_DEV(pr.bdf));
284 		if (slot) {
285 			debug("found entry for bus %d device %d, ",
286 			      PCI_BUS(pr.bdf), PCI_DEV(pr.bdf));
287 
288 			if (slot->irq[pr.pin - 1].link) {
289 				debug("skipping\n");
290 
291 				/*
292 				 * Sanity test on the routed PIRQ pin
293 				 *
294 				 * If they don't match, show a warning to tell
295 				 * there might be something wrong with the PIRQ
296 				 * routing information in the device tree.
297 				 */
298 				if (slot->irq[pr.pin - 1].link !=
299 				    pirq_linkno_to_reg(priv, pr.pirq))
300 					debug("WARNING: Inconsistent PIRQ routing information\n");
301 				continue;
302 			}
303 		} else {
304 			slot = slot_base + irq_entries++;
305 		}
306 		debug("writing INT%c\n", 'A' + pr.pin - 1);
307 		fill_irq_info(priv, slot, PCI_BUS(pr.bdf), PCI_DEV(pr.bdf),
308 			      pr.pin, pr.pirq);
309 	}
310 
311 	rt->size = irq_entries * sizeof(struct irq_info) + 32;
312 
313 	/* Fix up the table checksum */
314 	rt->checksum = table_compute_checksum(rt, rt->size);
315 
316 	gd->arch.pirq_routing_table = rt;
317 
318 	return 0;
319 }
320 
irq_enable_sci(struct udevice * dev)321 static void irq_enable_sci(struct udevice *dev)
322 {
323 	struct irq_router *priv = dev_get_priv(dev);
324 
325 	if (priv->actl_8bit) {
326 		/* Bit7 must be turned on to enable ACPI */
327 		dm_pci_write_config8(dev->parent, priv->actl_addr, 0x80);
328 	} else {
329 		/* Write 0 to enable SCI on IRQ9 */
330 		if (priv->config == PIRQ_VIA_PCI)
331 			dm_pci_write_config32(dev->parent, priv->actl_addr, 0);
332 		else
333 			writel(0, (uintptr_t)priv->ibase + priv->actl_addr);
334 	}
335 }
336 
irq_router_probe(struct udevice * dev)337 int irq_router_probe(struct udevice *dev)
338 {
339 	int ret;
340 
341 	ret = create_pirq_routing_table(dev);
342 	if (ret) {
343 		debug("Failed to create pirq routing table\n");
344 		return ret;
345 	}
346 	/* Route PIRQ */
347 	pirq_route_irqs(dev, gd->arch.pirq_routing_table->slots,
348 			get_irq_slot_count(gd->arch.pirq_routing_table));
349 
350 	if (IS_ENABLED(CONFIG_GENERATE_ACPI_TABLE))
351 		irq_enable_sci(dev);
352 
353 	return 0;
354 }
355 
356 static const struct udevice_id irq_router_ids[] = {
357 	{ .compatible = "intel,irq-router", .data = X86_IRQT_BASE },
358 	{ }
359 };
360 
361 U_BOOT_DRIVER(irq_router_drv) = {
362 	.name		= "intel_irq",
363 	.id		= UCLASS_IRQ,
364 	.of_match	= irq_router_ids,
365 	.probe		= irq_router_probe,
366 	.priv_auto	= sizeof(struct irq_router),
367 };
368