/* ------------------------------------------------------------ * rpa_vscsi.c * (C) Copyright IBM Corporation 1994, 2003 * Authors: Colin DeVilbiss (devilbis@us.ibm.com) * Santiago Leon (santil@us.ibm.com) * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 * USA * * ------------------------------------------------------------ * RPA-specific functions of the SCSI host adapter for Virtual I/O devices * * This driver allows the Linux SCSI peripheral drivers to directly * access devices in the hosting partition, either on an iSeries * hypervisor system or a converged hypervisor system. */ #include <asm/vio.h> #include <asm/prom.h> #include <asm/iommu.h> #include <asm/hvcall.h> #include <linux/dma-mapping.h> #include <linux/interrupt.h> #include "ibmvscsi.h" static char partition_name[97] = "UNKNOWN"; static unsigned int partition_number = -1; /* ------------------------------------------------------------ * Routines for managing the command/response queue */ /** * ibmvscsi_handle_event: - Interrupt handler for crq events * @irq: number of irq to handle, not used * @dev_instance: ibmvscsi_host_data of host that received interrupt * * Disables interrupts and schedules srp_task * Always returns IRQ_HANDLED */ static irqreturn_t ibmvscsi_handle_event(int irq, void *dev_instance) { struct ibmvscsi_host_data *hostdata = (struct ibmvscsi_host_data *)dev_instance; vio_disable_interrupts(to_vio_dev(hostdata->dev)); tasklet_schedule(&hostdata->srp_task); return IRQ_HANDLED; } /** * release_crq_queue: - Deallocates data and unregisters CRQ * @queue: crq_queue to initialize and register * @host_data: ibmvscsi_host_data of host * * Frees irq, deallocates a page for messages, unmaps dma, and unregisters * the crq with the hypervisor. */ void ibmvscsi_release_crq_queue(struct crq_queue *queue, struct ibmvscsi_host_data *hostdata, int max_requests) { long rc; struct vio_dev *vdev = to_vio_dev(hostdata->dev); free_irq(vdev->irq, (void *)hostdata); tasklet_kill(&hostdata->srp_task); do { rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address); } while ((rc == H_BUSY) || (H_IS_LONG_BUSY(rc))); dma_unmap_single(hostdata->dev, queue->msg_token, queue->size * sizeof(*queue->msgs), DMA_BIDIRECTIONAL); free_page((unsigned long)queue->msgs); } /** * crq_queue_next_crq: - Returns the next entry in message queue * @queue: crq_queue to use * * Returns pointer to next entry in queue, or NULL if there are no new * entried in the CRQ. */ static struct viosrp_crq *crq_queue_next_crq(struct crq_queue *queue) { struct viosrp_crq *crq; unsigned long flags; spin_lock_irqsave(&queue->lock, flags); crq = &queue->msgs[queue->cur]; if (crq->valid & 0x80) { if (++queue->cur == queue->size) queue->cur = 0; } else crq = NULL; spin_unlock_irqrestore(&queue->lock, flags); return crq; } /** * ibmvscsi_send_crq: - Send a CRQ * @hostdata: the adapter * @word1: the first 64 bits of the data * @word2: the second 64 bits of the data */ int ibmvscsi_send_crq(struct ibmvscsi_host_data *hostdata, u64 word1, u64 word2) { struct vio_dev *vdev = to_vio_dev(hostdata->dev); return plpar_hcall_norets(H_SEND_CRQ, vdev->unit_address, word1, word2); } /** * ibmvscsi_task: - Process srps asynchronously * @data: ibmvscsi_host_data of host */ static void ibmvscsi_task(void *data) { struct ibmvscsi_host_data *hostdata = (struct ibmvscsi_host_data *)data; struct vio_dev *vdev = to_vio_dev(hostdata->dev); struct viosrp_crq *crq; int done = 0; while (!done) { /* Pull all the valid messages off the CRQ */ while ((crq = crq_queue_next_crq(&hostdata->queue)) != NULL) { ibmvscsi_handle_crq(crq, hostdata); crq->valid = 0x00; } vio_enable_interrupts(vdev); if ((crq = crq_queue_next_crq(&hostdata->queue)) != NULL) { vio_disable_interrupts(vdev); ibmvscsi_handle_crq(crq, hostdata); crq->valid = 0x00; } else { done = 1; } } } static void gather_partition_info(void) { struct device_node *rootdn; const char *ppartition_name; const unsigned int *p_number_ptr; /* Retrieve information about this partition */ rootdn = of_find_node_by_path("/"); if (!rootdn) { return; } ppartition_name = of_get_property(rootdn, "ibm,partition-name", NULL); if (ppartition_name) strncpy(partition_name, ppartition_name, sizeof(partition_name)); p_number_ptr = of_get_property(rootdn, "ibm,partition-no", NULL); if (p_number_ptr) partition_number = *p_number_ptr; of_node_put(rootdn); } static void set_adapter_info(struct ibmvscsi_host_data *hostdata) { memset(&hostdata->madapter_info, 0x00, sizeof(hostdata->madapter_info)); dev_info(hostdata->dev, "SRP_VERSION: %s\n", SRP_VERSION); strcpy(hostdata->madapter_info.srp_version, SRP_VERSION); strncpy(hostdata->madapter_info.partition_name, partition_name, sizeof(hostdata->madapter_info.partition_name)); hostdata->madapter_info.partition_number = partition_number; hostdata->madapter_info.mad_version = 1; hostdata->madapter_info.os_type = 2; } /** * initialize_crq_queue: - Initializes and registers CRQ with hypervisor * @queue: crq_queue to initialize and register * @hostdata: ibmvscsi_host_data of host * * Allocates a page for messages, maps it for dma, and registers * the crq with the hypervisor. * Returns zero on success. */ int ibmvscsi_init_crq_queue(struct crq_queue *queue, struct ibmvscsi_host_data *hostdata, int max_requests) { int rc; int retrc; struct vio_dev *vdev = to_vio_dev(hostdata->dev); queue->msgs = (struct viosrp_crq *)get_zeroed_page(GFP_KERNEL); if (!queue->msgs) goto malloc_failed; queue->size = PAGE_SIZE / sizeof(*queue->msgs); queue->msg_token = dma_map_single(hostdata->dev, queue->msgs, queue->size * sizeof(*queue->msgs), DMA_BIDIRECTIONAL); if (dma_mapping_error(queue->msg_token)) goto map_failed; gather_partition_info(); set_adapter_info(hostdata); retrc = rc = plpar_hcall_norets(H_REG_CRQ, vdev->unit_address, queue->msg_token, PAGE_SIZE); if (rc == H_RESOURCE) /* maybe kexecing and resource is busy. try a reset */ rc = ibmvscsi_reset_crq_queue(queue, hostdata); if (rc == 2) { /* Adapter is good, but other end is not ready */ dev_warn(hostdata->dev, "Partner adapter not ready\n"); retrc = 0; } else if (rc != 0) { dev_warn(hostdata->dev, "Error %d opening adapter\n", rc); goto reg_crq_failed; } if (request_irq(vdev->irq, ibmvscsi_handle_event, 0, "ibmvscsi", (void *)hostdata) != 0) { dev_err(hostdata->dev, "couldn't register irq 0x%x\n", vdev->irq); goto req_irq_failed; } rc = vio_enable_interrupts(vdev); if (rc != 0) { dev_err(hostdata->dev, "Error %d enabling interrupts!!!\n", rc); goto req_irq_failed; } queue->cur = 0; spin_lock_init(&queue->lock); tasklet_init(&hostdata->srp_task, (void *)ibmvscsi_task, (unsigned long)hostdata); return retrc; req_irq_failed: do { rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address); } while ((rc == H_BUSY) || (H_IS_LONG_BUSY(rc))); reg_crq_failed: dma_unmap_single(hostdata->dev, queue->msg_token, queue->size * sizeof(*queue->msgs), DMA_BIDIRECTIONAL); map_failed: free_page((unsigned long)queue->msgs); malloc_failed: return -1; } /** * reenable_crq_queue: - reenables a crq after * @queue: crq_queue to initialize and register * @hostdata: ibmvscsi_host_data of host * */ int ibmvscsi_reenable_crq_queue(struct crq_queue *queue, struct ibmvscsi_host_data *hostdata) { int rc; struct vio_dev *vdev = to_vio_dev(hostdata->dev); /* Re-enable the CRQ */ do { rc = plpar_hcall_norets(H_ENABLE_CRQ, vdev->unit_address); } while ((rc == H_IN_PROGRESS) || (rc == H_BUSY) || (H_IS_LONG_BUSY(rc))); if (rc) dev_err(hostdata->dev, "Error %d enabling adapter\n", rc); return rc; } /** * reset_crq_queue: - resets a crq after a failure * @queue: crq_queue to initialize and register * @hostdata: ibmvscsi_host_data of host * */ int ibmvscsi_reset_crq_queue(struct crq_queue *queue, struct ibmvscsi_host_data *hostdata) { int rc; struct vio_dev *vdev = to_vio_dev(hostdata->dev); /* Close the CRQ */ do { rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address); } while ((rc == H_BUSY) || (H_IS_LONG_BUSY(rc))); /* Clean out the queue */ memset(queue->msgs, 0x00, PAGE_SIZE); queue->cur = 0; set_adapter_info(hostdata); /* And re-open it again */ rc = plpar_hcall_norets(H_REG_CRQ, vdev->unit_address, queue->msg_token, PAGE_SIZE); if (rc == 2) { /* Adapter is good, but other end is not ready */ dev_warn(hostdata->dev, "Partner adapter not ready\n"); } else if (rc != 0) { dev_warn(hostdata->dev, "couldn't register crq--rc 0x%x\n", rc); } return rc; }