xref: /openbmc/linux/arch/x86/kernel/apic/msi.c (revision 94cdda6b)
1 /*
2  * Support of MSI, HPET and DMAR interrupts.
3  *
4  * Copyright (C) 1997, 1998, 1999, 2000, 2009 Ingo Molnar, Hajnalka Szabo
5  *	Moved from arch/x86/kernel/apic/io_apic.c.
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 #include <linux/mm.h>
12 #include <linux/interrupt.h>
13 #include <linux/pci.h>
14 #include <linux/dmar.h>
15 #include <linux/hpet.h>
16 #include <linux/msi.h>
17 #include <asm/msidef.h>
18 #include <asm/hpet.h>
19 #include <asm/hw_irq.h>
20 #include <asm/apic.h>
21 #include <asm/irq_remapping.h>
22 
23 void native_compose_msi_msg(struct pci_dev *pdev,
24 			    unsigned int irq, unsigned int dest,
25 			    struct msi_msg *msg, u8 hpet_id)
26 {
27 	struct irq_cfg *cfg = irq_cfg(irq);
28 
29 	msg->address_hi = MSI_ADDR_BASE_HI;
30 
31 	if (x2apic_enabled())
32 		msg->address_hi |= MSI_ADDR_EXT_DEST_ID(dest);
33 
34 	msg->address_lo =
35 		MSI_ADDR_BASE_LO |
36 		((apic->irq_dest_mode == 0) ?
37 			MSI_ADDR_DEST_MODE_PHYSICAL :
38 			MSI_ADDR_DEST_MODE_LOGICAL) |
39 		((apic->irq_delivery_mode != dest_LowestPrio) ?
40 			MSI_ADDR_REDIRECTION_CPU :
41 			MSI_ADDR_REDIRECTION_LOWPRI) |
42 		MSI_ADDR_DEST_ID(dest);
43 
44 	msg->data =
45 		MSI_DATA_TRIGGER_EDGE |
46 		MSI_DATA_LEVEL_ASSERT |
47 		((apic->irq_delivery_mode != dest_LowestPrio) ?
48 			MSI_DATA_DELIVERY_FIXED :
49 			MSI_DATA_DELIVERY_LOWPRI) |
50 		MSI_DATA_VECTOR(cfg->vector);
51 }
52 
53 static int msi_compose_msg(struct pci_dev *pdev, unsigned int irq,
54 			   struct msi_msg *msg, u8 hpet_id)
55 {
56 	struct irq_cfg *cfg;
57 	int err;
58 	unsigned dest;
59 
60 	if (disable_apic)
61 		return -ENXIO;
62 
63 	cfg = irq_cfg(irq);
64 	err = assign_irq_vector(irq, cfg, apic->target_cpus());
65 	if (err)
66 		return err;
67 
68 	err = apic->cpu_mask_to_apicid_and(cfg->domain,
69 					   apic->target_cpus(), &dest);
70 	if (err)
71 		return err;
72 
73 	x86_msi.compose_msi_msg(pdev, irq, dest, msg, hpet_id);
74 
75 	return 0;
76 }
77 
78 static int
79 msi_set_affinity(struct irq_data *data, const struct cpumask *mask, bool force)
80 {
81 	struct irq_cfg *cfg = irqd_cfg(data);
82 	struct msi_msg msg;
83 	unsigned int dest;
84 	int ret;
85 
86 	ret = apic_set_affinity(data, mask, &dest);
87 	if (ret)
88 		return ret;
89 
90 	__get_cached_msi_msg(data->msi_desc, &msg);
91 
92 	msg.data &= ~MSI_DATA_VECTOR_MASK;
93 	msg.data |= MSI_DATA_VECTOR(cfg->vector);
94 	msg.address_lo &= ~MSI_ADDR_DEST_ID_MASK;
95 	msg.address_lo |= MSI_ADDR_DEST_ID(dest);
96 
97 	__pci_write_msi_msg(data->msi_desc, &msg);
98 
99 	return IRQ_SET_MASK_OK_NOCOPY;
100 }
101 
102 /*
103  * IRQ Chip for MSI PCI/PCI-X/PCI-Express Devices,
104  * which implement the MSI or MSI-X Capability Structure.
105  */
106 static struct irq_chip msi_chip = {
107 	.name			= "PCI-MSI",
108 	.irq_unmask		= pci_msi_unmask_irq,
109 	.irq_mask		= pci_msi_mask_irq,
110 	.irq_ack		= apic_ack_edge,
111 	.irq_set_affinity	= msi_set_affinity,
112 	.irq_retrigger		= apic_retrigger_irq,
113 	.flags			= IRQCHIP_SKIP_SET_WAKE,
114 };
115 
116 int setup_msi_irq(struct pci_dev *dev, struct msi_desc *msidesc,
117 		  unsigned int irq_base, unsigned int irq_offset)
118 {
119 	struct irq_chip *chip = &msi_chip;
120 	struct msi_msg msg;
121 	unsigned int irq = irq_base + irq_offset;
122 	int ret;
123 
124 	ret = msi_compose_msg(dev, irq, &msg, -1);
125 	if (ret < 0)
126 		return ret;
127 
128 	irq_set_msi_desc_off(irq_base, irq_offset, msidesc);
129 
130 	/*
131 	 * MSI-X message is written per-IRQ, the offset is always 0.
132 	 * MSI message denotes a contiguous group of IRQs, written for 0th IRQ.
133 	 */
134 	if (!irq_offset)
135 		pci_write_msi_msg(irq, &msg);
136 
137 	setup_remapped_irq(irq, irq_cfg(irq), chip);
138 
139 	irq_set_chip_and_handler_name(irq, chip, handle_edge_irq, "edge");
140 
141 	dev_dbg(&dev->dev, "irq %d for MSI/MSI-X\n", irq);
142 
143 	return 0;
144 }
145 
146 int native_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
147 {
148 	struct msi_desc *msidesc;
149 	unsigned int irq;
150 	int node, ret;
151 
152 	/* Multiple MSI vectors only supported with interrupt remapping */
153 	if (type == PCI_CAP_ID_MSI && nvec > 1)
154 		return 1;
155 
156 	node = dev_to_node(&dev->dev);
157 
158 	list_for_each_entry(msidesc, &dev->msi_list, list) {
159 		irq = irq_alloc_hwirq(node);
160 		if (!irq)
161 			return -ENOSPC;
162 
163 		ret = setup_msi_irq(dev, msidesc, irq, 0);
164 		if (ret < 0) {
165 			irq_free_hwirq(irq);
166 			return ret;
167 		}
168 
169 	}
170 	return 0;
171 }
172 
173 void native_teardown_msi_irq(unsigned int irq)
174 {
175 	irq_free_hwirq(irq);
176 }
177 
178 #ifdef CONFIG_DMAR_TABLE
179 static int
180 dmar_msi_set_affinity(struct irq_data *data, const struct cpumask *mask,
181 		      bool force)
182 {
183 	struct irq_cfg *cfg = irqd_cfg(data);
184 	unsigned int dest, irq = data->irq;
185 	struct msi_msg msg;
186 	int ret;
187 
188 	ret = apic_set_affinity(data, mask, &dest);
189 	if (ret)
190 		return ret;
191 
192 	dmar_msi_read(irq, &msg);
193 
194 	msg.data &= ~MSI_DATA_VECTOR_MASK;
195 	msg.data |= MSI_DATA_VECTOR(cfg->vector);
196 	msg.address_lo &= ~MSI_ADDR_DEST_ID_MASK;
197 	msg.address_lo |= MSI_ADDR_DEST_ID(dest);
198 	msg.address_hi = MSI_ADDR_BASE_HI | MSI_ADDR_EXT_DEST_ID(dest);
199 
200 	dmar_msi_write(irq, &msg);
201 
202 	return IRQ_SET_MASK_OK_NOCOPY;
203 }
204 
205 static struct irq_chip dmar_msi_type = {
206 	.name			= "DMAR_MSI",
207 	.irq_unmask		= dmar_msi_unmask,
208 	.irq_mask		= dmar_msi_mask,
209 	.irq_ack		= apic_ack_edge,
210 	.irq_set_affinity	= dmar_msi_set_affinity,
211 	.irq_retrigger		= apic_retrigger_irq,
212 	.flags			= IRQCHIP_SKIP_SET_WAKE,
213 };
214 
215 int arch_setup_dmar_msi(unsigned int irq)
216 {
217 	int ret;
218 	struct msi_msg msg;
219 
220 	ret = msi_compose_msg(NULL, irq, &msg, -1);
221 	if (ret < 0)
222 		return ret;
223 	dmar_msi_write(irq, &msg);
224 	irq_set_chip_and_handler_name(irq, &dmar_msi_type, handle_edge_irq,
225 				      "edge");
226 	return 0;
227 }
228 #endif
229 
230 /*
231  * MSI message composition
232  */
233 #ifdef CONFIG_HPET_TIMER
234 
235 static int hpet_msi_set_affinity(struct irq_data *data,
236 				 const struct cpumask *mask, bool force)
237 {
238 	struct irq_cfg *cfg = irqd_cfg(data);
239 	struct msi_msg msg;
240 	unsigned int dest;
241 	int ret;
242 
243 	ret = apic_set_affinity(data, mask, &dest);
244 	if (ret)
245 		return ret;
246 
247 	hpet_msi_read(data->handler_data, &msg);
248 
249 	msg.data &= ~MSI_DATA_VECTOR_MASK;
250 	msg.data |= MSI_DATA_VECTOR(cfg->vector);
251 	msg.address_lo &= ~MSI_ADDR_DEST_ID_MASK;
252 	msg.address_lo |= MSI_ADDR_DEST_ID(dest);
253 
254 	hpet_msi_write(data->handler_data, &msg);
255 
256 	return IRQ_SET_MASK_OK_NOCOPY;
257 }
258 
259 static struct irq_chip hpet_msi_type = {
260 	.name = "HPET_MSI",
261 	.irq_unmask = hpet_msi_unmask,
262 	.irq_mask = hpet_msi_mask,
263 	.irq_ack = apic_ack_edge,
264 	.irq_set_affinity = hpet_msi_set_affinity,
265 	.irq_retrigger = apic_retrigger_irq,
266 	.flags = IRQCHIP_SKIP_SET_WAKE,
267 };
268 
269 int default_setup_hpet_msi(unsigned int irq, unsigned int id)
270 {
271 	struct irq_chip *chip = &hpet_msi_type;
272 	struct msi_msg msg;
273 	int ret;
274 
275 	ret = msi_compose_msg(NULL, irq, &msg, id);
276 	if (ret < 0)
277 		return ret;
278 
279 	hpet_msi_write(irq_get_handler_data(irq), &msg);
280 	irq_set_status_flags(irq, IRQ_MOVE_PCNTXT);
281 	setup_remapped_irq(irq, irq_cfg(irq), chip);
282 
283 	irq_set_chip_and_handler_name(irq, chip, handle_edge_irq, "edge");
284 	return 0;
285 }
286 #endif
287