+ 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");
+ assert_msg(pos->buf.size, "HBA: expect a non-zero buffer size");
+
+ 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);
+ }
+
+ if (!ahci_try_send(port, slot)) {
+ goto fail;
+ }
+
+ /*
+ 等待数据到达内存
+ 解析IDENTIFY DEVICE传回来的数据。
+ 参考：
+ * ATA/ATAPI Command Set - 3 (ACS-3), Section 7.12.7
+ */
+ ahci_parse_dev_info(port->device, data_in);
+
+ if (!(port->device->flags & HBA_DEV_FATAPI)) {
+ goto done;
+ }
+
+ /*
+ 注意：ATAPI设备是无法通过IDENTIFY PACKET DEVICE 获取容量信息的。
+ 我们需要使用SCSI命令的READ_CAPACITY(16)进行获取。
+ 步骤如下：
+ 1. 因为ATAPI走的是SCSI，而AHCI对此专门进行了SATA的封装，
+ 也就是通过SATA的PACKET命令对SCSI命令进行封装。所以我们
+ 首先需要构建一个PACKET命令的FIS
+ 2. 接着，在ACMD中构建命令READ_CAPACITY的CDB - 一种SCSI命令的封装
+ 3. 然后把cmd_header->options的A位置位，表示这是一个送往ATAPI的命令。
+ 一点细节：
+ 1. HBA往底层SATA控制器发送PACKET FIS
+ 2. SATA控制器回复PIO Setup FIS
+ 3. HBA读入ACMD中的CDB，打包成Data FIS进行答复
+ 4. SATA控制器解包，拿到CDB，通过SCSI协议转发往ATAPI设备。
+ 5. ATAPI设备回复Return Parameter，SATA通过DMA Setup FIS
+ 发起DMA请求，HBA介入，将Return Parameter写入我们在PRDT
+ 里设置的data_in位置。
+ 4. 最后照常等待HBA把结果写入data_in，然后直接解析就好了。
+ 参考：
+ * ATA/ATAPI Command Set - 3 (ACS-3), Section 7.18
+ * SATA AHCI HBA Spec, Section 5.3.7
+ * SCSI Command Reference Manual, Section 3.26
+ */
+
+ sata_create_fis(cmd_fis, ATA_PACKET, 512 << 8, 0);
+
+ // for dev use 12 bytes cdb, READ_CAPACITY must use the 10 bytes variation.
+ if (port->device->cbd_size == SCSI_CDB12) {
+ struct scsi_cdb12* cdb12 = (struct scsi_cdb12*)cmd_table->atapi_cmd;
+ // ugly tricks to construct 10 byte cdb from 12 byte cdb
+ scsi_create_packet12(cdb12, SCSI_READ_CAPACITY_10, 0, 512 << 8);
+ } else {
+ struct scsi_cdb16* cdb16 = (struct scsi_cdb16*)cmd_table->atapi_cmd;
+ scsi_create_packet16(cdb16, SCSI_READ_CAPACITY_16, 0, 512);
+ cdb16->misc1 = 0x10; // service action
+ }
+
+ cmd_header->transferred_size = 0;
+ cmd_header->options |= HBA_CMDH_ATAPI;
+
+ if (!ahci_try_send(port, slot)) {
+ goto fail;
+ }
+
+ scsi_parse_capacity(port->device, (u32_t*)data_in);
+
+done:
+ // reset interrupt status and unmask D2HR interrupt
+ port->regs[HBA_RPxIE] |= HBA_MY_IE;
+ achi_register_ops(port);
+
+ vfree_dma(data_in);
+ vfree_dma(cmd_table);
+
+ return 1;
+
+fail:
+ port->regs[HBA_RPxIE] |= HBA_MY_IE;
+ vfree_dma(data_in);
+ vfree_dma(cmd_table);
+
+ return 0;
+}
+
+int
+ahci_identify_device(struct hba_device* device)
+{
+ // 用于重新识别设备（比如在热插拔的情况下）
+ // FIXME this is not right...
+ vfree(device);
+ return ahci_init_device(device->port);
+}
+
+void
+achi_register_ops(struct hba_port* port)
+{
+ port->device->ops.identify = ahci_identify_device;
+ if (!(port->device->flags & HBA_DEV_FATAPI)) {
+ port->device->ops.submit = sata_submit;
+ } else {
+ port->device->ops.submit = scsi_submit;
git://scm.lunaixsky.com / lunaix-os.git / blobdiff