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
loongson_vipi_read(struct loongson_kvm_ipi * ipi,gpa_t addr,int len,void * val)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
loongson_vipi_write(struct loongson_kvm_ipi * ipi,gpa_t addr,int len,const void * val)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
kvm_ipi_read(struct kvm_vcpu * vcpu,struct kvm_io_device * dev,gpa_t addr,int len,void * val)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
kvm_ipi_write(struct kvm_vcpu * vcpu,struct kvm_io_device * dev,gpa_t addr,int len,const void * val)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
kvm_init_loongson_ipi(struct kvm * kvm)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