3w-xxxx.c

讲述linux的初始化过程

				}
				if (tw_dev->state[request_id] != TW_S_POSTED) {
					printk(KERN_WARNING "3w-xxxx: tw_interrupt(): Received a request id (%d) (opcode = 0x%x) that wasn't posted.\n", request_id, command_packet->byte0.opcode);
				}
				error = 0;
				dprintk(KERN_NOTICE "3w-xxxx: tw_interrupt(): Response queue request id: %d.\n", request_id);
				/* Check for internal command */
				if (tw_dev->srb[request_id] == 0) {
					dprintk(KERN_WARNING "3w-xxxx: tw_interrupt(): Found internally posted command.\n");
					error = tw_aen_complete(tw_dev, request_id);
					if (error) {
						printk(KERN_WARNING "3w-xxxx: tw_interrupt(): Error completing aen.\n");
					}
					status_reg_value = inl(status_reg_addr);
					if (tw_check_bits(status_reg_value)) {
						printk(KERN_WARNING "3w-xxxx: tw_interrupt(): Unexpected bits.\n");
					}
		} else {
				switch (tw_dev->srb[request_id]->cmnd[0]) {
					case READ_10:
						dprintk(KERN_NOTICE "3w-xxxx: tw_interrupt(): caught READ_10\n");
					case READ_6:
						dprintk(KERN_NOTICE "3w-xxxx: tw_interrupt(): caught READ_6\n");
						break;
					case WRITE_10:
						dprintk(KERN_NOTICE "3w-xxxx: tw_interrupt(): caught WRITE_10\n");
					case WRITE_6:
						dprintk(KERN_NOTICE "3w-xxxx: tw_interrupt(): caught WRITE_6\n");
						break;
					case INQUIRY:
						dprintk(KERN_NOTICE "3w-xxxx: tw_interrupt(): caught INQUIRY\n");
						error = tw_scsiop_inquiry_complete(tw_dev, request_id);
						break;
					case READ_CAPACITY:
						dprintk(KERN_NOTICE "3w-xxxx: tw_interrupt(): caught READ_CAPACITY\n");
						error = tw_scsiop_read_capacity_complete(tw_dev, request_id);
						break;
					case TW_IOCTL:
						dprintk(KERN_NOTICE "3w-xxxx: tw_interrupt(): caught TW_IOCTL\n");
						error = tw_ioctl_complete(tw_dev, request_id);
						break;
					default:
						printk(KERN_WARNING "3w-xxxx: tw_interrupt(): Unknown scsi opcode: 0x%x.\n", tw_dev->srb[request_id]->cmnd[0]);
						tw_dev->srb[request_id]->result = (DID_BAD_TARGET << 16);
						tw_dev->srb[request_id]->scsi_done(tw_dev->srb[request_id]);
					}
					if (error) {
						/* Tell scsi layer there was an error */
						printk(KERN_WARNING "3w-xxxx: tw_interrupt(): Scsi Error.\n");
						tw_dev->srb[request_id]->result = (DID_ERROR << 16);
					} else {
						/* Tell scsi layer command was a success */
						tw_dev->srb[request_id]->result = (DID_OK << 16);
					}
					tw_dev->state[request_id] = TW_S_COMPLETED;
					tw_state_request_finish(tw_dev, request_id);
					tw_dev->posted_request_count--;
					tw_dev->srb[request_id]->scsi_done(tw_dev->srb[request_id]);
					status_reg_value = inl(status_reg_addr);
					if (tw_check_bits(status_reg_value)) {
						printk(KERN_WARNING "3w-xxxx: tw_interrupt(): Unexpected bits.\n");
					}
				}
			}
		}
		spin_unlock_irqrestore(&tw_dev->tw_lock, flags2);
	}
	spin_unlock_irqrestore(&io_request_lock, flags);
	clear_bit(TW_IN_INTR, &tw_dev->flags);
}	/* End tw_interrupt() */

/* This function handles ioctls from userspace to the driver */
int tw_ioctl(TW_Device_Extension *tw_dev, int request_id)
{
	unsigned char opcode;
	int bufflen;
	TW_Param *param;
	TW_Command *command_packet;
	u32 param_value;
	TW_Ioctl *ioctl = NULL;
	int tw_aen_code;

	ioctl = (TW_Ioctl *)tw_dev->srb[request_id]->request_buffer;
	if (ioctl == NULL) {
		printk(KERN_WARNING "3w-xxxx: tw_ioctl(): Request buffer NULL.\n");
		tw_dev->state[request_id] = TW_S_COMPLETED;
		tw_state_request_finish(tw_dev, request_id);
		tw_dev->srb[request_id]->result = (DID_OK << 16);
		tw_dev->srb[request_id]->scsi_done(tw_dev->srb[request_id]);
		return 0;
	}
	bufflen = tw_dev->srb[request_id]->request_bufflen;

	/* Initialize command packet */
	command_packet = (TW_Command *)tw_dev->command_packet_virtual_address[request_id];
	if (command_packet == NULL) {
		printk(KERN_WARNING "3w-xxxx: tw_ioctl(): Bad command packet virtual address.\n");
		tw_dev->state[request_id] = TW_S_COMPLETED;
		tw_state_request_finish(tw_dev, request_id);
		tw_dev->srb[request_id]->result = (DID_OK << 16);
		tw_dev->srb[request_id]->scsi_done(tw_dev->srb[request_id]);
		return 0;
	}
	memset(command_packet, 0, sizeof(TW_Sector));

	/* Initialize param */
	if (tw_dev->alignment_virtual_address[request_id] == NULL) {
		printk(KERN_WARNING "3w-xxxx: tw_ioctl(): Bad alignment virtual address.\n");
		tw_dev->state[request_id] = TW_S_COMPLETED;
		tw_state_request_finish(tw_dev, request_id);
		tw_dev->srb[request_id]->result = (DID_OK << 16);
		tw_dev->srb[request_id]->scsi_done(tw_dev->srb[request_id]);
		return 0;
	}
	param = (TW_Param *)tw_dev->alignment_virtual_address[request_id];
	memset(param, 0, sizeof(TW_Sector));

	dprintk(KERN_NOTICE "opcode = %d table_id = %d parameter_id = %d parameter_size_bytes = %d\n", ioctl->opcode, ioctl->table_id, ioctl->parameter_id,, ioctl->parameter_size_bytes);
	opcode = ioctl->opcode;

	switch (opcode) {
		case TW_OP_NOP:
			dprintk(KERN_NOTICE "3w-xxxx: tw_ioctl(): caught TW_OP_NOP.\n");
			command_packet->byte0.opcode = TW_OP_NOP;
			break;
		case TW_OP_GET_PARAM:
			dprintk(KERN_NOTICE "3w-xxxx: tw_ioctl(): caught TW_OP_GET_PARAM.\n");
			command_packet->byte0.opcode = TW_OP_GET_PARAM;
			param->table_id = ioctl->table_id;
			param->parameter_id = ioctl->parameter_id;
			param->parameter_size_bytes = ioctl->parameter_size_bytes;
			tw_dev->ioctl_size[request_id] = ioctl->parameter_size_bytes;
			dprintk(KERN_NOTICE "table_id = %d parameter_id = %d parameter_size_bytes %d\n", param->table_id, param->parameter_id, param->parameter_size_bytes);
			break;
		case TW_OP_SET_PARAM:
			dprintk(KERN_NOTICE "3w-xxxx: tw_ioctl(): caught TW_OP_SET_PARAM: table_id = %d, parameter_id = %d, parameter_size_bytes = %d.\n",
			ioctl->table_id, ioctl->parameter_id, ioctl->parameter_size_bytes);
			command_packet->byte0.opcode = TW_OP_SET_PARAM;
			param->table_id = ioctl->table_id;
			param->parameter_id = ioctl->parameter_id;
			param->parameter_size_bytes = ioctl->parameter_size_bytes;
			memcpy(param->data, ioctl->data, ioctl->parameter_size_bytes);
			break;
		case TW_OP_AEN_LISTEN:
			dprintk(KERN_NOTICE "3w-xxxx: tw_ioctl(): caught TW_OP_AEN_LISTEN.\n");
			if (tw_dev->aen_head == tw_dev->aen_tail) {
				/* aen queue empty */
				dprintk(KERN_NOTICE "3w-xxxx: tw_ioctl(): Aen queue empty.\n");
				tw_aen_code = TW_AEN_QUEUE_EMPTY;
				memcpy(tw_dev->srb[request_id]->request_buffer, &tw_aen_code, ioctl->parameter_size_bytes);
			} else {
				/* Copy aen queue entry to request buffer */
				dprintk(KERN_NOTICE "3w-xxxx: tw_ioctl(): Returning aen 0x%x\n", tw_dev->aen_queue[tw_dev->aen_head]);
				tw_aen_code = tw_dev->aen_queue[tw_dev->aen_head];
				memcpy(tw_dev->srb[request_id]->request_buffer, &tw_aen_code, ioctl->parameter_size_bytes);
				if (tw_dev->aen_head == TW_Q_LENGTH - 1) {
					tw_dev->aen_head = TW_Q_START;
				} else {
					tw_dev->aen_head = tw_dev->aen_head + 1;
				}
			}
			tw_dev->state[request_id] = TW_S_COMPLETED;
			tw_state_request_finish(tw_dev, request_id);
			tw_dev->srb[request_id]->result = (DID_OK << 16);
			tw_dev->srb[request_id]->scsi_done(tw_dev->srb[request_id]);
			return 0;
	        case TW_CMD_PACKET:
		  memcpy(command_packet, ioctl->data, sizeof(TW_Command));
		  command_packet->request_id = request_id;
		  tw_post_command_packet(tw_dev, request_id);

		  return 0;
		default:
			printk(KERN_WARNING "3w-xxxx: Unknown ioctl 0x%x.\n", opcode);
			tw_dev->state[request_id] = TW_S_COMPLETED;
			tw_state_request_finish(tw_dev, request_id);
			tw_dev->srb[request_id]->result = (DID_OK << 16);
			tw_dev->srb[request_id]->scsi_done(tw_dev->srb[request_id]);
			return 0;
	}

	param_value = tw_dev->alignment_physical_address[request_id];
	if (param_value == 0) {
		printk(KERN_WARNING "3w-xxxx: tw_ioctl(): Bad alignment physical address.\n");
		tw_dev->state[request_id] = TW_S_COMPLETED;
		tw_state_request_finish(tw_dev, request_id);
		tw_dev->srb[request_id]->result = (DID_OK << 16);
		tw_dev->srb[request_id]->scsi_done(tw_dev->srb[request_id]);
	}

	command_packet->byte8.param.sgl[0].address = param_value;
	command_packet->byte8.param.sgl[0].length = sizeof(TW_Sector);

	command_packet->byte0.sgl_offset = 2;
	command_packet->size = 4;
	command_packet->request_id = request_id;
	command_packet->byte3.unit = 0;
	command_packet->byte3.host_id = 0;
	command_packet->status = 0;
	command_packet->flags = 0;
	command_packet->byte6.parameter_count = 1;

	/* Now try to post the command to the board */
	tw_post_command_packet(tw_dev, request_id);

	return 0;
} /* End tw_ioctl() */

/* This function is called by the isr to complete ioctl requests */
int tw_ioctl_complete(TW_Device_Extension *tw_dev, int request_id)
{
	unsigned char *param_data;
	unsigned char *buff;
	TW_Param *param;

	dprintk(KERN_NOTICE "3w-xxxx: tw_ioctl_complete()\n");
	buff = tw_dev->srb[request_id]->request_buffer;
	if (buff == NULL) {
		printk(KERN_WARNING "3w-xxxx: tw_ioctl_complete(): Request buffer NULL.\n");
		return 1;
	}
	dprintk(KERN_NOTICE "3w-xxxx: tw_ioctl_complete(): Request_bufflen = %d\n", tw_dev->srb[request_id]->request_bufflen);
	memset(buff, 0, tw_dev->srb[request_id]->request_bufflen);
	param = (TW_Param *)tw_dev->alignment_virtual_address[request_id];
	if (param == NULL) {
		printk(KERN_WARNING "3w-xxxx: tw_scsiop_read_capacity_complete(): Bad alignment virtual address.\n");
		return 1;
	}
	param_data = &(param->data[0]);

	memcpy(buff, param_data, tw_dev->ioctl_size[request_id]);

	return 0;
} /* End tw_ioctl_complete() */

/* This function will mask the command interrupt */
void tw_mask_command_interrupt(TW_Device_Extension *tw_dev)
{
	u32 control_reg_addr, control_reg_value;
	
	control_reg_addr = tw_dev->registers.control_reg_addr;
	control_reg_value = TW_CONTROL_MASK_COMMAND_INTERRUPT;
	outl(control_reg_value, control_reg_addr);
} /* End tw_mask_command_interrupt() */

/* This function will poll the status register for a flag */
int tw_poll_status(TW_Device_Extension *tw_dev, u32 flag, int seconds)
{
	u32 status_reg_addr, status_reg_value;
	struct timeval before, timeout;

	status_reg_addr = tw_dev->registers.status_reg_addr;
	do_gettimeofday(&before);
	status_reg_value = inl(status_reg_addr);

	while ((status_reg_value & flag) != flag) {
		status_reg_value = inl(status_reg_addr);
		do_gettimeofday(&timeout);
		if (before.tv_sec + seconds < timeout.tv_sec) { 
			printk(KERN_WARNING "3w-xxxx: tw_poll_status(): Flag 0x%x not found.\n", flag);
			return 1;
		}
		mdelay(1);
	}
	return 0;
} /* End tw_poll_status() */

/* This function will attempt to post a command packet to the board */
int tw_post_command_packet(TW_Device_Extension *tw_dev, int request_id)
{
	u32 status_reg_addr, status_reg_value;
	u32 command_que_addr, command_que_value;

	dprintk(KERN_NOTICE "3w-xxxx: tw_post_command_packet()\n");
	command_que_addr = tw_dev->registers.command_que_addr;
	command_que_value = tw_dev->command_packet_physical_address[request_id];
	status_reg_addr = tw_dev->registers.status_reg_addr;
	status_reg_value = inl(status_reg_addr);

	if (tw_check_bits(status_reg_value)) 
		printk(KERN_WARNING "3w-xxxx: tw_post_command_packet(): Unexpected bits.\n");

	if ((status_reg_value & TW_STATUS_COMMAND_QUEUE_FULL) == 0) {
		/* We successfully posted the command packet */
		outl(command_que_value, command_que_addr);
		tw_dev->state[request_id] = TW_S_POSTED;
		tw_dev->posted_request_count++;
		if (tw_dev->posted_request_count > tw_dev->max_posted_request_count) {
			tw_dev->max_posted_request_count = tw_dev->posted_request_count;
		}
	} else {
		/* Couldn't post the command packet, so we do it in the isr */
		if (tw_dev->state[request_id] != TW_S_PENDING) {
			tw_dev->state[request_id] = TW_S_PENDING;
			tw_dev->pending_request_count++;
			if (tw_dev->pending_request_count > tw_dev->max_pending_request_count) {
				tw_dev->max_pending_request_count = tw_dev->pending_request_count;
			}
			tw_dev->pending_queue[tw_dev->pending_tail] = request_id;
			if (tw_dev->pending_tail == TW_Q_LENGTH-1) {
				tw_dev->pending_tail = TW_Q_START;
			} else {
				tw_dev->pending_tail = tw_dev->pending_tail + 1;
			}
		} 
		tw_unmask_command_interrupt(tw_dev);
		return 1;
	}
	return 0;
} /* End tw_post_command_packet() */

/* This function will reset a device extension */
int tw_reset_device_extension(TW_Device_Extension *tw_dev) 
{
	int imax = 0;
	int i = 0;
	Scsi_Cmnd *srb;

	dprintk(KERN_NOTICE "3w-xxxx: tw_reset_device_extension()\n");
	imax = TW_Q_LENGTH;

	if (tw_reset_sequence(tw_dev)) {
		printk(KERN_WARNING "3w-xxxx: tw_reset_device_extension(): Reset sequence failed for card %d.\n", tw_dev->host->host_no);
		return 1;
	}

	/* Abort all requests that are in progress */
	for (i=0;i<imax;i++) {
		if ((tw_dev->state[i] != TW_S_FINISHED) && 
		    (tw_dev->state[i] != TW_S_INITIAL) &&
		    (tw_dev->state[i] != TW_S_COMPLETED)) {
			srb = tw_dev->srb[i];
			srb->result = (DID_RESET << 16);
			tw_dev->srb[i]->scsi_done(tw_dev->srb[i]);
		}
	}

	/* Reset queues and counts */
	for (i=0;i<imax;i++) {
		tw_dev->free_queue[i] = i;
		tw_dev->state[i] = TW_S_INITIAL;
	}
	tw_dev->free_head = TW_Q_START;
	tw_dev->free_tail = TW_Q_LENGTH - 1;
	tw_dev->posted_request_count = 0;
	tw_dev->pending_request_count = 0;
	tw_dev->pending_head = TW_Q_START;
	tw_dev->pending_tail = TW_Q_START;

	return 0;
} /* End tw_reset_device_extension() */

/* This function will reset a controller */
int tw_reset_sequence(TW_Device_Extension *tw_dev) 
{
	int error = 0;
	int tries = 0;

	/* Disable interrupts */
	tw_disable_interrupts(tw_dev);

	/* Reset the board */
	while (tries < TW_MAX_RESET_TRIES) {
		tw_soft_reset(tw_dev);

		error = tw_aen_drain_queue(tw_dev);
		if (error) {
			printk(KERN_WARNING "3w-xxxx: tw_reset_sequence(): No attention interrupt for card %d.\n", tw_dev->host->host_no);
			tries++;
			continue;
		}

		/* Check for controller errors */
		if (tw_check_errors(tw_dev)) {
			printk(KERN_WARNING "3w-xxxx: tw_reset_sequence(): Controller errors found, soft resetting card %d.\n", tw_dev->host->host_no);
			tries++;
			continue;
		}