1 files changed, 260 insertions, 0 deletions
diff --git a/drivers/scsi/ibmvscsi/rpa_vscsi.c b/drivers/scsi/ibmvscsi/rpa_vscsi.c
new file mode 100644
index 0000000..50cb909
--- /dev/null
+++ b/drivers/scsi/ibmvscsi/rpa_vscsi.c
@@ -0,0 +1,260 @@
+/* ------------------------------------------------------------
+ * 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/iommu.h>
+#include <asm/hvcall.h>
+#include <linux/dma-mapping.h>
+#include <linux/interrupt.h>
+#include "ibmvscsi.h"
+
+/* ------------------------------------------------------------
+ * 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
+ * @regs:	pt_regs with registers
+ *
+ * Disables interrupts and schedules srp_task
+ * Always returns IRQ_HANDLED
+ */
+static irqreturn_t ibmvscsi_handle_event(int irq,
+					 void *dev_instance,
+					 struct pt_regs *regs)
+{
+	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_isLongBusy(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;
+		}
+	}
+}
+
+/**
+ * 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;
+	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;
+
+	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 */
+		printk(KERN_WARNING "ibmvscsi: Partner adapter not ready\n");
+	} else if (rc != 0) {
+		printk(KERN_WARNING "ibmvscsi: Error %d opening adapter\n", rc);
+		goto reg_crq_failed;
+	}
+
+	if (request_irq(vdev->irq,
+			ibmvscsi_handle_event,
+			0, "ibmvscsi", (void *)hostdata) != 0) {
+		printk(KERN_ERR "ibmvscsi: couldn't register irq 0x%x\n",
+		       vdev->irq);
+		goto req_irq_failed;
+	}
+
+	rc = vio_enable_interrupts(vdev);
+	if (rc != 0) {
+		printk(KERN_ERR "ibmvscsi:  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 0;
+
+      req_irq_failed:
+	do {
+		rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
+	} while ((rc == H_Busy) || (H_isLongBusy(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;
+}
+
+/**
+ * reset_crq_queue: - resets a crq after a failure
+ * @queue:	crq_queue to initialize and register
+ * @hostdata:	ibmvscsi_host_data of host
+ *
+ */
+void 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_isLongBusy(rc)));
+
+	/* Clean out the queue */
+	memset(queue->msgs, 0x00, PAGE_SIZE);
+	queue->cur = 0;
+
+	/* 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 */
+		printk(KERN_WARNING "ibmvscsi: Partner adapter not ready\n");
+	} else if (rc != 0) {
+		printk(KERN_WARNING
+		       "ibmvscsi: couldn't register crq--rc 0x%x\n", rc);
+	}
+}