cxl-device-utils.c (8449B)
1 /* 2 * CXL Utility library for devices 3 * 4 * Copyright(C) 2020 Intel Corporation. 5 * 6 * This work is licensed under the terms of the GNU GPL, version 2. See the 7 * COPYING file in the top-level directory. 8 */ 9 10 #include "qemu/osdep.h" 11 #include "qemu/log.h" 12 #include "hw/cxl/cxl.h" 13 14 /* 15 * Device registers have no restrictions per the spec, and so fall back to the 16 * default memory mapped register rules in 8.2: 17 * Software shall use CXL.io Memory Read and Write to access memory mapped 18 * register defined in this section. Unless otherwise specified, software 19 * shall restrict the accesses width based on the following: 20 * • A 32 bit register shall be accessed as a 1 Byte, 2 Bytes or 4 Bytes 21 * quantity. 22 * • A 64 bit register shall be accessed as a 1 Byte, 2 Bytes, 4 Bytes or 8 23 * Bytes 24 * • The address shall be a multiple of the access width, e.g. when 25 * accessing a register as a 4 Byte quantity, the address shall be 26 * multiple of 4. 27 * • The accesses shall map to contiguous bytes.If these rules are not 28 * followed, the behavior is undefined 29 */ 30 31 static uint64_t caps_reg_read(void *opaque, hwaddr offset, unsigned size) 32 { 33 CXLDeviceState *cxl_dstate = opaque; 34 35 if (size == 4) { 36 return cxl_dstate->caps_reg_state32[offset / sizeof(*cxl_dstate->caps_reg_state32)]; 37 } else { 38 return cxl_dstate->caps_reg_state64[offset / sizeof(*cxl_dstate->caps_reg_state64)]; 39 } 40 } 41 42 static uint64_t dev_reg_read(void *opaque, hwaddr offset, unsigned size) 43 { 44 return 0; 45 } 46 47 static uint64_t mailbox_reg_read(void *opaque, hwaddr offset, unsigned size) 48 { 49 CXLDeviceState *cxl_dstate = opaque; 50 51 switch (size) { 52 case 1: 53 return cxl_dstate->mbox_reg_state[offset]; 54 case 2: 55 return cxl_dstate->mbox_reg_state16[offset / size]; 56 case 4: 57 return cxl_dstate->mbox_reg_state32[offset / size]; 58 case 8: 59 return cxl_dstate->mbox_reg_state64[offset / size]; 60 default: 61 g_assert_not_reached(); 62 } 63 } 64 65 static void mailbox_mem_writel(uint32_t *reg_state, hwaddr offset, 66 uint64_t value) 67 { 68 switch (offset) { 69 case A_CXL_DEV_MAILBOX_CTRL: 70 /* fallthrough */ 71 case A_CXL_DEV_MAILBOX_CAP: 72 /* RO register */ 73 break; 74 default: 75 qemu_log_mask(LOG_UNIMP, 76 "%s Unexpected 32-bit access to 0x%" PRIx64 " (WI)\n", 77 __func__, offset); 78 return; 79 } 80 81 reg_state[offset / sizeof(*reg_state)] = value; 82 } 83 84 static void mailbox_mem_writeq(uint64_t *reg_state, hwaddr offset, 85 uint64_t value) 86 { 87 switch (offset) { 88 case A_CXL_DEV_MAILBOX_CMD: 89 break; 90 case A_CXL_DEV_BG_CMD_STS: 91 /* BG not supported */ 92 /* fallthrough */ 93 case A_CXL_DEV_MAILBOX_STS: 94 /* Read only register, will get updated by the state machine */ 95 return; 96 default: 97 qemu_log_mask(LOG_UNIMP, 98 "%s Unexpected 64-bit access to 0x%" PRIx64 " (WI)\n", 99 __func__, offset); 100 return; 101 } 102 103 104 reg_state[offset / sizeof(*reg_state)] = value; 105 } 106 107 static void mailbox_reg_write(void *opaque, hwaddr offset, uint64_t value, 108 unsigned size) 109 { 110 CXLDeviceState *cxl_dstate = opaque; 111 112 if (offset >= A_CXL_DEV_CMD_PAYLOAD) { 113 memcpy(cxl_dstate->mbox_reg_state + offset, &value, size); 114 return; 115 } 116 117 switch (size) { 118 case 4: 119 mailbox_mem_writel(cxl_dstate->mbox_reg_state32, offset, value); 120 break; 121 case 8: 122 mailbox_mem_writeq(cxl_dstate->mbox_reg_state64, offset, value); 123 break; 124 default: 125 g_assert_not_reached(); 126 } 127 128 if (ARRAY_FIELD_EX32(cxl_dstate->mbox_reg_state32, CXL_DEV_MAILBOX_CTRL, 129 DOORBELL)) { 130 cxl_process_mailbox(cxl_dstate); 131 } 132 } 133 134 static uint64_t mdev_reg_read(void *opaque, hwaddr offset, unsigned size) 135 { 136 uint64_t retval = 0; 137 138 retval = FIELD_DP64(retval, CXL_MEM_DEV_STS, MEDIA_STATUS, 1); 139 retval = FIELD_DP64(retval, CXL_MEM_DEV_STS, MBOX_READY, 1); 140 141 return retval; 142 } 143 144 static void ro_reg_write(void *opaque, hwaddr offset, uint64_t value, 145 unsigned size) 146 { 147 /* Many register sets are read only */ 148 } 149 150 static const MemoryRegionOps mdev_ops = { 151 .read = mdev_reg_read, 152 .write = ro_reg_write, 153 .endianness = DEVICE_LITTLE_ENDIAN, 154 .valid = { 155 .min_access_size = 1, 156 .max_access_size = 8, 157 .unaligned = false, 158 }, 159 .impl = { 160 .min_access_size = 8, 161 .max_access_size = 8, 162 }, 163 }; 164 165 static const MemoryRegionOps mailbox_ops = { 166 .read = mailbox_reg_read, 167 .write = mailbox_reg_write, 168 .endianness = DEVICE_LITTLE_ENDIAN, 169 .valid = { 170 .min_access_size = 1, 171 .max_access_size = 8, 172 .unaligned = false, 173 }, 174 .impl = { 175 .min_access_size = 1, 176 .max_access_size = 8, 177 }, 178 }; 179 180 static const MemoryRegionOps dev_ops = { 181 .read = dev_reg_read, 182 .write = ro_reg_write, 183 .endianness = DEVICE_LITTLE_ENDIAN, 184 .valid = { 185 .min_access_size = 1, 186 .max_access_size = 8, 187 .unaligned = false, 188 }, 189 .impl = { 190 .min_access_size = 1, 191 .max_access_size = 8, 192 }, 193 }; 194 195 static const MemoryRegionOps caps_ops = { 196 .read = caps_reg_read, 197 .write = ro_reg_write, 198 .endianness = DEVICE_LITTLE_ENDIAN, 199 .valid = { 200 .min_access_size = 1, 201 .max_access_size = 8, 202 .unaligned = false, 203 }, 204 .impl = { 205 .min_access_size = 4, 206 .max_access_size = 8, 207 }, 208 }; 209 210 void cxl_device_register_block_init(Object *obj, CXLDeviceState *cxl_dstate) 211 { 212 /* This will be a BAR, so needs to be rounded up to pow2 for PCI spec */ 213 memory_region_init(&cxl_dstate->device_registers, obj, "device-registers", 214 pow2ceil(CXL_MMIO_SIZE)); 215 216 memory_region_init_io(&cxl_dstate->caps, obj, &caps_ops, cxl_dstate, 217 "cap-array", CXL_CAPS_SIZE); 218 memory_region_init_io(&cxl_dstate->device, obj, &dev_ops, cxl_dstate, 219 "device-status", CXL_DEVICE_STATUS_REGISTERS_LENGTH); 220 memory_region_init_io(&cxl_dstate->mailbox, obj, &mailbox_ops, cxl_dstate, 221 "mailbox", CXL_MAILBOX_REGISTERS_LENGTH); 222 memory_region_init_io(&cxl_dstate->memory_device, obj, &mdev_ops, 223 cxl_dstate, "memory device caps", 224 CXL_MEMORY_DEVICE_REGISTERS_LENGTH); 225 226 memory_region_add_subregion(&cxl_dstate->device_registers, 0, 227 &cxl_dstate->caps); 228 memory_region_add_subregion(&cxl_dstate->device_registers, 229 CXL_DEVICE_STATUS_REGISTERS_OFFSET, 230 &cxl_dstate->device); 231 memory_region_add_subregion(&cxl_dstate->device_registers, 232 CXL_MAILBOX_REGISTERS_OFFSET, 233 &cxl_dstate->mailbox); 234 memory_region_add_subregion(&cxl_dstate->device_registers, 235 CXL_MEMORY_DEVICE_REGISTERS_OFFSET, 236 &cxl_dstate->memory_device); 237 } 238 239 static void device_reg_init_common(CXLDeviceState *cxl_dstate) { } 240 241 static void mailbox_reg_init_common(CXLDeviceState *cxl_dstate) 242 { 243 /* 2048 payload size, with no interrupt or background support */ 244 ARRAY_FIELD_DP32(cxl_dstate->mbox_reg_state32, CXL_DEV_MAILBOX_CAP, 245 PAYLOAD_SIZE, CXL_MAILBOX_PAYLOAD_SHIFT); 246 cxl_dstate->payload_size = CXL_MAILBOX_MAX_PAYLOAD_SIZE; 247 } 248 249 static void memdev_reg_init_common(CXLDeviceState *cxl_dstate) { } 250 251 void cxl_device_register_init_common(CXLDeviceState *cxl_dstate) 252 { 253 uint64_t *cap_hdrs = cxl_dstate->caps_reg_state64; 254 const int cap_count = 3; 255 256 /* CXL Device Capabilities Array Register */ 257 ARRAY_FIELD_DP64(cap_hdrs, CXL_DEV_CAP_ARRAY, CAP_ID, 0); 258 ARRAY_FIELD_DP64(cap_hdrs, CXL_DEV_CAP_ARRAY, CAP_VERSION, 1); 259 ARRAY_FIELD_DP64(cap_hdrs, CXL_DEV_CAP_ARRAY, CAP_COUNT, cap_count); 260 261 cxl_device_cap_init(cxl_dstate, DEVICE_STATUS, 1); 262 device_reg_init_common(cxl_dstate); 263 264 cxl_device_cap_init(cxl_dstate, MAILBOX, 2); 265 mailbox_reg_init_common(cxl_dstate); 266 267 cxl_device_cap_init(cxl_dstate, MEMORY_DEVICE, 0x4000); 268 memdev_reg_init_common(cxl_dstate); 269 270 assert(cxl_initialize_mailbox(cxl_dstate) == 0); 271 }