+ strrtrim(str);
+}
+
+int
+ahci_try_send(struct hba_port* port, int slot)
+{
+ int retries = 0, bitmask = 1 << slot;
+
+ // 确保端口是空闲的
+ wait_until(!(port->regs[HBA_RPxTFD] & (HBA_PxTFD_BSY | HBA_PxTFD_DRQ)));
+
+ hba_clear_reg(port->regs[HBA_RPxIS]);
+
+ while (retries < MAX_RETRY) {
+ // PxCI寄存器置位,告诉HBA这儿有个数据需要发送到SATA端口
+ port->regs[HBA_RPxCI] = bitmask;
+
+ wait_until_expire(!(port->regs[HBA_RPxCI] & bitmask), 1000000);
+
+ port->regs[HBA_RPxCI] &= ~bitmask; // ensure CI bit is cleared
+ if ((port->regs[HBA_RPxTFD] & HBA_PxTFD_ERR)) {
+ // 有错误
+ sata_read_error(port);
+ retries++;
+ } else {
+ break;
+ }
+ }
+
+ hba_clear_reg(port->regs[HBA_RPxIS]);
+
+ return retries < MAX_RETRY;
+}
+
+void
+ahci_post(struct hba_port* port, struct hba_cmd_state* state, int slot)
+{
+ int bitmask = 1 << slot;
+
+ // 确保端口是空闲的
+ wait_until(!(port->regs[HBA_RPxTFD] & (HBA_PxTFD_BSY | HBA_PxTFD_DRQ)));
+
+ hba_clear_reg(port->regs[HBA_RPxIS]);
+
+ port->cmdctx.issued[slot] = state;
+ port->cmdctx.tracked_ci |= bitmask;
+ port->regs[HBA_RPxCI] |= bitmask;