int rio_inb_pwrite_handler()

in rio.c [1170:1332]

• 109 lines of code
• 21 McCabe index (conditional complexity)

int rio_inb_pwrite_handler(struct rio_mport *mport, union rio_pw_msg *pw_msg)
{
	struct rio_dev *rdev;
	u32 err_status, em_perrdet, em_ltlerrdet;
	int rc, portnum;
	struct rio_pwrite *pwrite;

#ifdef DEBUG_PW
	{
		u32 i;

		pr_debug("%s: PW to mport_%d:\n", __func__, mport->id);
		for (i = 0; i < RIO_PW_MSG_SIZE / sizeof(u32); i = i + 4) {
			pr_debug("0x%02x: %08x %08x %08x %08x\n",
				i * 4, pw_msg->raw[i], pw_msg->raw[i + 1],
				pw_msg->raw[i + 2], pw_msg->raw[i + 3]);
		}
	}
#endif

	rdev = rio_get_comptag((pw_msg->em.comptag & RIO_CTAG_UDEVID), NULL);
	if (rdev) {
		pr_debug("RIO: Port-Write message from %s\n", rio_name(rdev));
	} else {
		pr_debug("RIO: %s No matching device for CTag 0x%08x\n",
			__func__, pw_msg->em.comptag);
	}

	/* Call a device-specific handler (if it is registered for the device).
	 * This may be the service for endpoints that send device-specific
	 * port-write messages. End-point messages expected to be handled
	 * completely by EP specific device driver.
	 * For switches rc==0 signals that no standard processing required.
	 */
	if (rdev && rdev->pwcback) {
		rc = rdev->pwcback(rdev, pw_msg, 0);
		if (rc == 0)
			return 0;
	}

	mutex_lock(&mport->lock);
	list_for_each_entry(pwrite, &mport->pwrites, node)
		pwrite->pwcback(mport, pwrite->context, pw_msg, 0);
	mutex_unlock(&mport->lock);

	if (!rdev)
		return 0;

	/*
	 * FIXME: The code below stays as it was before for now until we decide
	 * how to do default PW handling in combination with per-mport callbacks
	 */

	portnum = pw_msg->em.is_port & 0xFF;

	/* Check if device and route to it are functional:
	 * Sometimes devices may send PW message(s) just before being
	 * powered down (or link being lost).
	 */
	if (rio_chk_dev_access(rdev)) {
		pr_debug("RIO: device access failed - get link partner\n");
		/* Scan route to the device and identify failed link.
		 * This will replace device and port reported in PW message.
		 * PW message should not be used after this point.
		 */
		if (rio_chk_dev_route(rdev, &rdev, &portnum)) {
			pr_err("RIO: Route trace for %s failed\n",
				rio_name(rdev));
			return -EIO;
		}
		pw_msg = NULL;
	}

	/* For End-point devices processing stops here */
	if (!(rdev->pef & RIO_PEF_SWITCH))
		return 0;

	if (rdev->phys_efptr == 0) {
		pr_err("RIO_PW: Bad switch initialization for %s\n",
			rio_name(rdev));
		return 0;
	}

	/*
	 * Process the port-write notification from switch
	 */
	if (rdev->rswitch->ops && rdev->rswitch->ops->em_handle)
		rdev->rswitch->ops->em_handle(rdev, portnum);

	rio_read_config_32(rdev, RIO_DEV_PORT_N_ERR_STS_CSR(rdev, portnum),
			   &err_status);
	pr_debug("RIO_PW: SP%d_ERR_STS_CSR=0x%08x\n", portnum, err_status);

	if (err_status & RIO_PORT_N_ERR_STS_PORT_OK) {

		if (!(rdev->rswitch->port_ok & (1 << portnum))) {
			rdev->rswitch->port_ok |= (1 << portnum);
			rio_set_port_lockout(rdev, portnum, 0);
			/* Schedule Insertion Service */
			pr_debug("RIO_PW: Device Insertion on [%s]-P%d\n",
			       rio_name(rdev), portnum);
		}

		/* Clear error-stopped states (if reported).
		 * Depending on the link partner state, two attempts
		 * may be needed for successful recovery.
		 */
		if (err_status & (RIO_PORT_N_ERR_STS_OUT_ES |
				  RIO_PORT_N_ERR_STS_INP_ES)) {
			if (rio_clr_err_stopped(rdev, portnum, err_status))
				rio_clr_err_stopped(rdev, portnum, 0);
		}
	}  else { /* if (err_status & RIO_PORT_N_ERR_STS_PORT_UNINIT) */

		if (rdev->rswitch->port_ok & (1 << portnum)) {
			rdev->rswitch->port_ok &= ~(1 << portnum);
			rio_set_port_lockout(rdev, portnum, 1);

			if (rdev->phys_rmap == 1) {
			rio_write_config_32(rdev,
				RIO_DEV_PORT_N_ACK_STS_CSR(rdev, portnum),
				RIO_PORT_N_ACK_CLEAR);
			} else {
				rio_write_config_32(rdev,
					RIO_DEV_PORT_N_OB_ACK_CSR(rdev, portnum),
					RIO_PORT_N_OB_ACK_CLEAR);
				rio_write_config_32(rdev,
					RIO_DEV_PORT_N_IB_ACK_CSR(rdev, portnum),
					0);
			}

			/* Schedule Extraction Service */
			pr_debug("RIO_PW: Device Extraction on [%s]-P%d\n",
			       rio_name(rdev), portnum);
		}
	}

	rio_read_config_32(rdev,
		rdev->em_efptr + RIO_EM_PN_ERR_DETECT(portnum), &em_perrdet);
	if (em_perrdet) {
		pr_debug("RIO_PW: RIO_EM_P%d_ERR_DETECT=0x%08x\n",
			 portnum, em_perrdet);
		/* Clear EM Port N Error Detect CSR */
		rio_write_config_32(rdev,
			rdev->em_efptr + RIO_EM_PN_ERR_DETECT(portnum), 0);
	}

	rio_read_config_32(rdev,
		rdev->em_efptr + RIO_EM_LTL_ERR_DETECT, &em_ltlerrdet);
	if (em_ltlerrdet) {
		pr_debug("RIO_PW: RIO_EM_LTL_ERR_DETECT=0x%08x\n",
			 em_ltlerrdet);
		/* Clear EM L/T Layer Error Detect CSR */
		rio_write_config_32(rdev,
			rdev->em_efptr + RIO_EM_LTL_ERR_DETECT, 0);
	}

	/* Clear remaining error bits and Port-Write Pending bit */
	rio_write_config_32(rdev, RIO_DEV_PORT_N_ERR_STS_CSR(rdev, portnum),
			    err_status);

	return 0;
}