+ cmd_fis->head.type = SATA_REG_FIS_H2D;
+ cmd_fis->head.options = SATA_REG_FIS_COMMAND;
+ cmd_fis->head.status_cmd = command;
+ cmd_fis->dev = 0;
+
+ cmd_fis->lba0 = SATA_LBA_COMPONENT(lba, 0);
+ cmd_fis->lba8 = SATA_LBA_COMPONENT(lba, 8);
+ cmd_fis->lba16 = SATA_LBA_COMPONENT(lba, 16);
+ cmd_fis->lba24 = SATA_LBA_COMPONENT(lba, 24);
+
+ cmd_fis->lba32 = SATA_LBA_COMPONENT(lba, 32);
+ cmd_fis->lba40 = SATA_LBA_COMPONENT(lba, 40);
+
+ cmd_fis->count = sector_count;
+}
+
+int
+hba_bind_sbuf(struct hba_cmdh* cmdh, struct hba_cmdt* cmdt, struct membuf mbuf)
+{
+ assert_msg(mbuf.size <= 0x400000U, "HBA: Buffer too big");
+ cmdh->prdt_len = 1;
+ cmdt->entries[0] =
+ (struct hba_prdte){ .data_base = vmm_v2p((ptr_t)mbuf.buffer),
+ .byte_count = mbuf.size - 1 };
+
+ return 0;
+}
+
+int
+hba_bind_vbuf(struct hba_cmdh* cmdh, struct hba_cmdt* cmdt, struct vecbuf* vbuf)
+{
+ size_t i = 0;
+ struct vecbuf* pos = vbuf;
+
+ do {
+ assert_msg(i < HBA_MAX_PRDTE, "HBA: Too many PRDTEs");
+ assert_msg(pos->buf.size <= 0x400000U, "HBA: Buffer too big");
+
+ cmdt->entries[i++] =
+ (struct hba_prdte){ .data_base = vmm_v2p((ptr_t)pos->buf.buffer),
+ .byte_count = pos->buf.size - 1 };
+ pos = list_entry(pos->components.next, struct vecbuf, components);
+ } while (pos != vbuf);
+
+ cmdh->prdt_len = i + 1;
+
+ return 0;
+}
+
+int
+hba_prepare_cmd(struct hba_port* port,
+ struct hba_cmdt** cmdt,
+ struct hba_cmdh** cmdh)
+{
+ int slot = __get_free_slot(port);
+ assert_msg(slot >= 0, "HBA: No free slot");
+
+ // 构建命令头(Command Header)和命令表(Command Table)
+ struct hba_cmdh* cmd_header = &port->cmdlst[slot];
+ struct hba_cmdt* cmd_table = vzalloc_dma(sizeof(struct hba_cmdt));
+
+ memset(cmd_header, 0, sizeof(*cmd_header));
+
+ // 将命令表挂到命令头上
+ cmd_header->cmd_table_base = vmm_v2p((ptr_t)cmd_table);
+ cmd_header->options =
+ HBA_CMDH_FIS_LEN(sizeof(struct sata_reg_fis)) | HBA_CMDH_CLR_BUSY;
+
+ *cmdh = cmd_header;
+ *cmdt = cmd_table;
+
+ return slot;
+}
+
+int
+ahci_init_device(struct hba_port* port)
+{
+ /* 发送ATA命令,参考:SATA AHCI Spec Rev.1.3.1, section 5.5 */
+ struct hba_cmdt* cmd_table;
+ struct hba_cmdh* cmd_header;
+
+ // mask DHR interrupt
+ port->regs[HBA_RPxIE] &= ~HBA_MY_IE;
+
+ // 预备DMA接收缓存,用于存放HBA传回的数据
+ u16_t* data_in = (u16_t*)valloc_dma(512);
+
+ int slot = hba_prepare_cmd(port, &cmd_table, &cmd_header);
+ hba_bind_sbuf(
+ cmd_header, cmd_table, (struct membuf){ .buffer = data_in, .size = 512 });
+
+ port->device = vzalloc(sizeof(struct hba_device));
+ port->device->port = port;
+ port->device->hba = port->hba;
+
+ // 在命令表中构建命令FIS
+ struct sata_reg_fis* cmd_fis = (struct sata_reg_fis*)cmd_table->command_fis;
+
+ // 根据设备类型使用合适的命令
+ if (port->regs[HBA_RPxSIG] == HBA_DEV_SIG_ATA) {
+ // ATA 一般为硬盘
+ sata_create_fis(cmd_fis, ATA_IDENTIFY_DEVICE, 0, 0);
+ } else {
+ // ATAPI 一般为光驱,软驱,或者磁带机
+ port->device->flags |= HBA_DEV_FATAPI;
+ sata_create_fis(cmd_fis, ATA_IDENTIFY_PAKCET_DEVICE, 0, 0);