arch/mips/kvm/loongson_ipi.c

   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
  51 static 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
  96 static 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, 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, 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
 151 static 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(&ipi->lock, flags);
 164
 165         return 0;
 166 }
 167
 168 static 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(&ipi->lock, flags);
 181
 182         return 0;
 183 }
 184
 185 static const struct kvm_io_device_ops kvm_ipi_ops = {
 186         .read     = kvm_ipi_read,
 187         .write    = kvm_ipi_write,
 188 };
 189
 190 void 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, KVM_MMIO_BUS, addr, 0x400, device);
 210                 mutex_unlock(&kvm->slots_lock);
 211                 s->dev_ipi[i].ipi = s;
 212                 s->dev_ipi[i].node_id = i;
 213         }
 214 }