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

source code of linux/arch/mips/kvm/loongson_ipi.c