3w-xxxx.c

讲述linux的初始化过程

	return numcards;
} /* End tw_findcards() */

/* This function will free up device extension resources */
void tw_free_device_extension(TW_Device_Extension *tw_dev)
{
	int i, imax;
	imax = TW_Q_LENGTH;

	dprintk(KERN_NOTICE "3w-xxxx: tw_free_device_extension()\n");
	/* Free command packet and generic buffer memory */
	for (i=0;i<imax;i++) {
		if (tw_dev->command_packet_virtual_address[i]) 
			kfree(tw_dev->command_packet_virtual_address[i]);

		if (tw_dev->alignment_virtual_address[i])
			kfree(tw_dev->alignment_virtual_address[i]);
	}
} /* End tw_free_device_extension() */

/* Clean shutdown routine */
static int tw_halt(struct notifier_block *nb, ulong event, void *buf)
{
	int i;

	for (i=0;i<tw_device_extension_count;i++) {
		printk(KERN_NOTICE "3w-xxxx: Notifying card #%d\n", i);
		tw_shutdown_device(tw_device_extension_list[i]);
	}
	unregister_reboot_notifier(&tw_notifier);

	return NOTIFY_OK;
} /* End tw_halt() */

/* This function will send an initconnection command to controller */
int tw_initconnection(TW_Device_Extension *tw_dev, int message_credits) 
{
	u32 command_que_addr, command_que_value;
	u32 status_reg_addr, status_reg_value;
	u32 response_que_addr;
	TW_Command  *command_packet;
	TW_Response_Queue response_queue;
	int request_id = 0;
	int i = 0;
	int imax = 0;

	dprintk(KERN_NOTICE "3w-xxxx: tw_initconnection()\n");
	command_que_addr = tw_dev->registers.command_que_addr;
	status_reg_addr = tw_dev->registers.status_reg_addr;
	response_que_addr = tw_dev->registers.response_que_addr;

	/* Initialize InitConnection command packet */
	if (tw_dev->command_packet_virtual_address[request_id] == NULL) {
		printk(KERN_WARNING "3w-xxxx: tw_initconnection(): Bad command packet virtual address.\n");
		return 1;
	}

	command_packet = (TW_Command *)tw_dev->command_packet_virtual_address[request_id];
	memset(command_packet, 0, sizeof(TW_Sector));
	command_packet->byte0.opcode = TW_OP_INIT_CONNECTION;
	command_packet->byte0.sgl_offset = 0x0;
	command_packet->size = TW_INIT_COMMAND_PACKET_SIZE;
	command_packet->request_id = request_id;
	command_packet->byte3.unit = 0x0;
	command_packet->byte3.host_id = 0x0;
	command_packet->status = 0x0;
	command_packet->flags = 0x0;
	command_packet->byte6.message_credits = message_credits; 
	command_packet->byte8.init_connection.response_queue_pointer = 0x0;
	command_que_value = tw_dev->command_packet_physical_address[request_id];

	if (command_que_value == 0) {
		printk(KERN_WARNING "3w-xxxx: tw_initconnection(): Bad command packet physical address.\n");
		return 1;
	}
  
	/* Send command packet to the board */
	outl(command_que_value, command_que_addr);
    
	/* Poll for completion */
	imax = TW_POLL_MAX_RETRIES;
	for (i=0;i<imax;i++) {
		mdelay(10);
		status_reg_value = inl(status_reg_addr);
		if (tw_check_bits(status_reg_value)) {
			printk(KERN_WARNING "3w-xxxx: tw_initconnection(): Unexpected bits.\n");
			return 1;
		}
		if ((status_reg_value & TW_STATUS_RESPONSE_QUEUE_EMPTY) == 0) {
			response_queue.value = inl(response_que_addr);
			request_id = (unsigned char)response_queue.u.response_id;
			if (request_id != 0) {
				/* unexpected request id */
				printk(KERN_WARNING "3w-xxxx: tw_initconnection(): Unexpected request id.\n");
				return 1;
			}
			if (command_packet->status != 0) {
				/* bad response */
				printk(KERN_WARNING "3w-xxxx: tw_initconnection(): Bad response, status = 0x%x, flags = 0x%x.\n", command_packet->status, command_packet->flags);
				return 1;
			}
			break;	/* Response was okay, so we exit */
		}
	}
	return 0;
} /* End tw_initconnection() */

/* This function will initialize the fields of a device extension */
int tw_initialize_device_extension(TW_Device_Extension *tw_dev)
{
	int i, imax;

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

	for (i=0; i<imax; i++) {
		/* Initialize command packet buffers */
		tw_allocate_memory(tw_dev, i, sizeof(TW_Sector), 0);
		if (tw_dev->command_packet_virtual_address[i] == NULL) {
			printk(KERN_WARNING "3w-xxxx: tw_initialize_device_extension(): Bad command packet virtual address.\n");
			return 1;
		}
		memset(tw_dev->command_packet_virtual_address[i], 0, sizeof(TW_Sector));
    
		/* Initialize generic buffer */
		tw_allocate_memory(tw_dev, i, sizeof(TW_Sector), 1);
		if (tw_dev->alignment_virtual_address[i] == NULL) {
			printk(KERN_WARNING "3w-xxxx: tw_initialize_device_extension(): Bad alignment virtual address.\n");
			return 1;
		}
		memset(tw_dev->alignment_virtual_address[i], 0, sizeof(TW_Sector));

		tw_dev->free_queue[i] = i;
		tw_dev->state[i] = TW_S_INITIAL;
		tw_dev->ioctl_size[i] = 0;
		tw_dev->aen_queue[i] = 0;
	}

	for (i=0;i<TW_MAX_UNITS;i++)
		tw_dev->is_unit_present[i] = 0;

	tw_dev->num_units = 0;
	tw_dev->num_aborts = 0;
	tw_dev->num_resets = 0;
	tw_dev->free_head = TW_Q_START;
	tw_dev->free_tail = TW_Q_LENGTH - 1;
	tw_dev->posted_request_count = 0;
	tw_dev->max_posted_request_count = 0;
	tw_dev->max_sgl_entries = 0;
	tw_dev->sgl_entries = 0;
	tw_dev->host = NULL;
	tw_dev->pending_head = TW_Q_START;
	tw_dev->pending_tail = TW_Q_START;
	tw_dev->aen_head = 0;
	tw_dev->aen_tail = 0;
	tw_dev->sector_count = 0;
	tw_dev->max_sector_count = 0;
	spin_lock_init(&tw_dev->tw_lock);
	tw_dev->flags = 0;
	return 0;
} /* End tw_initialize_device_extension() */

/* This function will get unit info from the controller */
int tw_initialize_units(TW_Device_Extension *tw_dev) 
{
	int found = 0;
	unsigned char request_id = 0;
	TW_Command *command_packet;
	TW_Param *param;
	int i, imax, num_units = 0;
	u32 status_reg_addr, status_reg_value;
	u32 command_que_addr, command_que_value;
	u32 response_que_addr;
	TW_Response_Queue response_queue;
	u32 param_value;
	unsigned char *is_unit_present;

	dprintk(KERN_NOTICE "3w-xxxx: tw_initialize_units()\n");

	status_reg_addr = tw_dev->registers.status_reg_addr;
	command_que_addr = tw_dev->registers.command_que_addr;
	response_que_addr = tw_dev->registers.response_que_addr;
  
	/* Setup the command packet */
	command_packet = (TW_Command *)tw_dev->command_packet_virtual_address[request_id];
	if (command_packet == NULL) {
		printk(KERN_WARNING "3w-xxxx: tw_initialize_units(): Bad command packet virtual address.\n");
		return 1;
	}
	memset(command_packet, 0, sizeof(TW_Sector));
	command_packet->byte0.opcode      = TW_OP_GET_PARAM;
	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.block_count = 1;

	/* Now setup the param */
	if (tw_dev->alignment_virtual_address[request_id] == NULL) {
		printk(KERN_WARNING "3w-xxxx: tw_initialize_units(): Bad alignment virtual address.\n");
		return 1;
	}
	param = (TW_Param *)tw_dev->alignment_virtual_address[request_id];
	memset(param, 0, sizeof(TW_Sector));
	param->table_id = 3;       /* unit summary table */
	param->parameter_id = 3;   /* unitstatus parameter */
	param->parameter_size_bytes = TW_MAX_UNITS;
	param_value = tw_dev->alignment_physical_address[request_id];
	if (param_value == 0) {
		printk(KERN_WARNING "3w-xxxx: tw_initialize_units(): Bad alignment physical address.\n");
		return 1;
	}

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

	/* Post the command packet to the board */
	command_que_value = tw_dev->command_packet_physical_address[request_id];
	if (command_que_value == 0) {
		printk(KERN_WARNING "3w-xxxx: tw_initialize_units(): Bad command packet physical address.\n");
		return 1;
	}
	outl(command_que_value, command_que_addr);

	/* Poll for completion */
	imax = TW_POLL_MAX_RETRIES;
	for(i=0; i<imax; i++) {
		mdelay(10);
		status_reg_value = inl(status_reg_addr);
		if (tw_check_bits(status_reg_value)) {
			printk(KERN_WARNING "3w-xxxx: tw_initialize_units(): Unexpected bits.\n");
			return 1;
		}
		if ((status_reg_value & TW_STATUS_RESPONSE_QUEUE_EMPTY) == 0) {
			response_queue.value = inl(response_que_addr);
			request_id = (unsigned char)response_queue.u.response_id;
			if (request_id != 0) {
				/* unexpected request id */
				printk(KERN_WARNING "3w-xxxx: tw_initialize_units(): Unexpected request id.\n");
				return 1;
			}
			if (command_packet->status != 0) {
				/* bad response */
				printk(KERN_WARNING "3w-xxxx: tw_initialize_units(): Bad response, status = 0x%x, flags = 0x%x.\n", command_packet->status, command_packet->flags);
				return 1;
			}
			found = 1;
			break;
		}
	}
	if (found == 0) {
		/* response never received */
		printk(KERN_WARNING "3w-xxxx: tw_initialize_units(): No response.\n");
		return 1;
	}

	param = (TW_Param *)tw_dev->alignment_virtual_address[request_id];
	is_unit_present = (unsigned char *)&(param->data[0]);
  
	/* Show all units present */
	imax = TW_MAX_UNITS;
	for(i=0; i<imax; i++) {
		if (is_unit_present[i] == 0) {
			tw_dev->is_unit_present[i] = FALSE;
		} else {
		  if (is_unit_present[i] & TW_UNIT_ONLINE) {
			dprintk(KERN_NOTICE "3w-xxxx: tw_initialize_units(): Unit %d found.\n", i);
			tw_dev->is_unit_present[i] = TRUE;
			num_units++;
		  }
		}
	}
	tw_dev->num_units = num_units;

	if (num_units == 0) {
		printk(KERN_NOTICE "3w-xxxx: tw_initialize_units(): No units found.\n");
		return 1;
	}
  
	return 0;
} /* End tw_initialize_units() */

/* This function is the interrupt service routine */
static void tw_interrupt(int irq, void *dev_instance, struct pt_regs *regs) 
{
	int request_id;
	u32 status_reg_addr, status_reg_value;
	u32 response_que_addr;
	TW_Device_Extension *tw_dev = (TW_Device_Extension *)dev_instance;
	TW_Response_Queue response_que;
	int error = 0;
	int do_response_interrupt=0;
	int do_attention_interrupt=0;
	int do_host_interrupt=0;
	int do_command_interrupt=0;
	int flags = 0;
	int flags2 = 0;
	TW_Command *command_packet;
	if (test_and_set_bit(TW_IN_INTR, &tw_dev->flags))
		return;
	spin_lock_irqsave(&io_request_lock, flags);

	if (tw_dev->tw_pci_dev->irq == irq) {
		spin_lock_irqsave(&tw_dev->tw_lock, flags2);
		dprintk(KERN_NOTICE "3w-xxxx: tw_interrupt()\n");

		/* Read the registers */
		status_reg_addr = tw_dev->registers.status_reg_addr;
		response_que_addr = tw_dev->registers.response_que_addr;
		status_reg_value = inl(status_reg_addr);

		/* Check which interrupt */
		if (status_reg_value & TW_STATUS_HOST_INTERRUPT)
			do_host_interrupt=1;
		if (status_reg_value & TW_STATUS_ATTENTION_INTERRUPT)
			do_attention_interrupt=1;
		if (status_reg_value & TW_STATUS_COMMAND_INTERRUPT)
			do_command_interrupt=1;
		if (status_reg_value & TW_STATUS_RESPONSE_INTERRUPT)
			do_response_interrupt=1;

		/* Handle host interrupt */
		if (do_host_interrupt) {
			dprintk(KERN_NOTICE "3w-xxxx: tw_interrupt(): Received host interrupt.\n");
			tw_clear_host_interrupt(tw_dev);
		}

		/* Handle attention interrupt */
		if (do_attention_interrupt) {
			dprintk(KERN_NOTICE "3w-xxxx: tw_interrupt(): Received attention interrupt.\n");
			tw_state_request_start(tw_dev, &request_id);
			error = tw_aen_read_queue(tw_dev, request_id);
			if (error) {
				printk(KERN_WARNING "3w-xxxx: tw_interrupt(): Error reading aen queue.\n");
				tw_dev->state[request_id] = TW_S_COMPLETED;
				tw_state_request_finish(tw_dev, request_id);
			} else {
				dprintk(KERN_WARNING "3w-xxxx: tw_interrupt(): Clearing attention interrupt.\n");
				tw_clear_attention_interrupt(tw_dev);
			}
		}

		/* Handle command interrupt */
		if (do_command_interrupt) {
			/* Drain as many pending commands as we can */
			while (tw_dev->pending_request_count > 0) {
				request_id = tw_dev->pending_queue[tw_dev->pending_head];
				if (tw_dev->state[request_id] != TW_S_PENDING) {
					printk(KERN_WARNING "3w-xxxx: tw_interrupt(): Found request id that wasn't pending.\n");
					break;
				}
				if (tw_post_command_packet(tw_dev, request_id)==0) {
					if (tw_dev->pending_head == TW_Q_LENGTH-1) {
						tw_dev->pending_head = TW_Q_START;
					} else {
						tw_dev->pending_head = tw_dev->pending_head + 1;
					}
					tw_dev->pending_request_count--;
				} else {
					break;
				}
			}
			/* If there are no more pending requests, we mask command interrupt */
			if (tw_dev->pending_request_count == 0) 
				tw_mask_command_interrupt(tw_dev);
		}

		/* Handle response interrupt */
		if (do_response_interrupt) {
			/* Drain the response queue from the board */
			while ((status_reg_value & TW_STATUS_RESPONSE_QUEUE_EMPTY) == 0) {
				response_que.value = inl(response_que_addr);
				request_id = response_que.u.response_id;
				command_packet = (TW_Command *)tw_dev->command_packet_virtual_address[request_id];
				if (command_packet->status != 0) {
					printk(KERN_WARNING "3w-xxxx: tw_interrupt(): Bad response, status = 0x%x, flags = 0x%x.\n", command_packet->status, command_packet->flags);