xref: /linux/arch/mips/kvm/loongson_ipi.c (revision da5b2ad1c2f18834cb1ce429e2e5a5cf5cbdf21b)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Loongson-3 Virtual IPI interrupt support.
4  *
5  * Copyright (C) 2019  Loongson Technologies, Inc.  All rights reserved.
6  *
7  * Authors: Chen Zhu <zhuchen@loongson.cn>
8  * Authors: Huacai Chen <chenhc@lemote.com>
9  */
10 
11 #include <linux/kvm_host.h>
12 
13 #include "interrupt.h"
14 
15 #define IPI_BASE            0x3ff01000ULL
16 
17 #define CORE0_STATUS_OFF       0x000
18 #define CORE0_EN_OFF           0x004
19 #define CORE0_SET_OFF          0x008
20 #define CORE0_CLEAR_OFF        0x00c
21 #define CORE0_BUF_20           0x020
22 #define CORE0_BUF_28           0x028
23 #define CORE0_BUF_30           0x030
24 #define CORE0_BUF_38           0x038
25 
26 #define CORE1_STATUS_OFF       0x100
27 #define CORE1_EN_OFF           0x104
28 #define CORE1_SET_OFF          0x108
29 #define CORE1_CLEAR_OFF        0x10c
30 #define CORE1_BUF_20           0x120
31 #define CORE1_BUF_28           0x128
32 #define CORE1_BUF_30           0x130
33 #define CORE1_BUF_38           0x138
34 
35 #define CORE2_STATUS_OFF       0x200
36 #define CORE2_EN_OFF           0x204
37 #define CORE2_SET_OFF          0x208
38 #define CORE2_CLEAR_OFF        0x20c
39 #define CORE2_BUF_20           0x220
40 #define CORE2_BUF_28           0x228
41 #define CORE2_BUF_30           0x230
42 #define CORE2_BUF_38           0x238
43 
44 #define CORE3_STATUS_OFF       0x300
45 #define CORE3_EN_OFF           0x304
46 #define CORE3_SET_OFF          0x308
47 #define CORE3_CLEAR_OFF        0x30c
48 #define CORE3_BUF_20           0x320
49 #define CORE3_BUF_28           0x328
50 #define CORE3_BUF_30           0x330
51 #define CORE3_BUF_38           0x338
52 
53 static int loongson_vipi_read(struct loongson_kvm_ipi *ipi,
54 				gpa_t addr, int len, void *val)
55 {
56 	uint32_t core = (addr >> 8) & 3;
57 	uint32_t node = (addr >> 44) & 3;
58 	uint32_t id = core + node * 4;
59 	uint64_t offset = addr & 0xff;
60 	void *pbuf;
61 	struct ipi_state *s = &(ipi->ipistate[id]);
62 
63 	BUG_ON(offset & (len - 1));
64 
65 	switch (offset) {
66 	case CORE0_STATUS_OFF:
67 		*(uint64_t *)val = s->status;
68 		break;
69 
70 	case CORE0_EN_OFF:
71 		*(uint64_t *)val = s->en;
72 		break;
73 
74 	case CORE0_SET_OFF:
75 		*(uint64_t *)val = 0;
76 		break;
77 
78 	case CORE0_CLEAR_OFF:
79 		*(uint64_t *)val = 0;
80 		break;
81 
82 	case CORE0_BUF_20 ... CORE0_BUF_38:
83 		pbuf = (void *)s->buf + (offset - 0x20);
84 		if (len == 8)
85 			*(uint64_t *)val = *(uint64_t *)pbuf;
86 		else /* Assume len == 4 */
87 			*(uint32_t *)val = *(uint32_t *)pbuf;
88 		break;
89 
90 	default:
91 		pr_notice("%s with unknown addr %llx\n", __func__, addr);
92 		break;
93 	}
94 
95 	return 0;
96 }
97 
98 static int loongson_vipi_write(struct loongson_kvm_ipi *ipi,
99 				gpa_t addr, int len, const void *val)
100 {
101 	uint32_t core = (addr >> 8) & 3;
102 	uint32_t node = (addr >> 44) & 3;
103 	uint32_t id = core + node * 4;
104 	uint64_t data, offset = addr & 0xff;
105 	void *pbuf;
106 	struct kvm *kvm = ipi->kvm;
107 	struct kvm_mips_interrupt irq;
108 	struct ipi_state *s = &(ipi->ipistate[id]);
109 
110 	data = *(uint64_t *)val;
111 	BUG_ON(offset & (len - 1));
112 
113 	switch (offset) {
114 	case CORE0_STATUS_OFF:
115 		break;
116 
117 	case CORE0_EN_OFF:
118 		s->en = data;
119 		break;
120 
121 	case CORE0_SET_OFF:
122 		s->status |= data;
123 		irq.cpu = id;
124 		irq.irq = 6;
125 		kvm_vcpu_ioctl_interrupt(kvm_get_vcpu(kvm, id), &irq);
126 		break;
127 
128 	case CORE0_CLEAR_OFF:
129 		s->status &= ~data;
130 		if (!s->status) {
131 			irq.cpu = id;
132 			irq.irq = -6;
133 			kvm_vcpu_ioctl_interrupt(kvm_get_vcpu(kvm, id), &irq);
134 		}
135 		break;
136 
137 	case CORE0_BUF_20 ... CORE0_BUF_38:
138 		pbuf = (void *)s->buf + (offset - 0x20);
139 		if (len == 8)
140 			*(uint64_t *)pbuf = (uint64_t)data;
141 		else /* Assume len == 4 */
142 			*(uint32_t *)pbuf = (uint32_t)data;
143 		break;
144 
145 	default:
146 		pr_notice("%s with unknown addr %llx\n", __func__, addr);
147 		break;
148 	}
149 
150 	return 0;
151 }
152 
153 static int kvm_ipi_read(struct kvm_vcpu *vcpu, struct kvm_io_device *dev,
154 			gpa_t addr, int len, void *val)
155 {
156 	unsigned long flags;
157 	struct loongson_kvm_ipi *ipi;
158 	struct ipi_io_device *ipi_device;
159 
160 	ipi_device = container_of(dev, struct ipi_io_device, device);
161 	ipi = ipi_device->ipi;
162 
163 	spin_lock_irqsave(&ipi->lock, flags);
164 	loongson_vipi_read(ipi, addr, len, val);
165 	spin_unlock_irqrestore(&ipi->lock, flags);
166 
167 	return 0;
168 }
169 
170 static int kvm_ipi_write(struct kvm_vcpu *vcpu, struct kvm_io_device *dev,
171 			gpa_t addr, int len, const void *val)
172 {
173 	unsigned long flags;
174 	struct loongson_kvm_ipi *ipi;
175 	struct ipi_io_device *ipi_device;
176 
177 	ipi_device = container_of(dev, struct ipi_io_device, device);
178 	ipi = ipi_device->ipi;
179 
180 	spin_lock_irqsave(&ipi->lock, flags);
181 	loongson_vipi_write(ipi, addr, len, val);
182 	spin_unlock_irqrestore(&ipi->lock, flags);
183 
184 	return 0;
185 }
186 
187 static const struct kvm_io_device_ops kvm_ipi_ops = {
188 	.read     = kvm_ipi_read,
189 	.write    = kvm_ipi_write,
190 };
191 
192 void kvm_init_loongson_ipi(struct kvm *kvm)
193 {
194 	int i;
195 	unsigned long addr;
196 	struct loongson_kvm_ipi *s;
197 	struct kvm_io_device *device;
198 
199 	s = &kvm->arch.ipi;
200 	s->kvm = kvm;
201 	spin_lock_init(&s->lock);
202 
203 	/*
204 	 * Initialize IPI device
205 	 */
206 	for (i = 0; i < 4; i++) {
207 		device = &s->dev_ipi[i].device;
208 		kvm_iodevice_init(device, &kvm_ipi_ops);
209 		addr = (((unsigned long)i) << 44) + IPI_BASE;
210 		mutex_lock(&kvm->slots_lock);
211 		kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, addr, 0x400, device);
212 		mutex_unlock(&kvm->slots_lock);
213 		s->dev_ipi[i].ipi = s;
214 		s->dev_ipi[i].node_id = i;
215 	}
216 }
217