merge filename and modify references to iseries/hv_lp_event.h
[linux-2.6.git] / drivers / scsi / ibmvscsi / rpa_vscsi.c
1 /* ------------------------------------------------------------
2  * rpa_vscsi.c
3  * (C) Copyright IBM Corporation 1994, 2003
4  * Authors: Colin DeVilbiss (devilbis@us.ibm.com)
5  *          Santiago Leon (santil@us.ibm.com)
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
20  * USA
21  *
22  * ------------------------------------------------------------
23  * RPA-specific functions of the SCSI host adapter for Virtual I/O devices
24  *
25  * This driver allows the Linux SCSI peripheral drivers to directly
26  * access devices in the hosting partition, either on an iSeries
27  * hypervisor system or a converged hypervisor system.
28  */
29
30 #include <asm/vio.h>
31 #include <asm/prom.h>
32 #include <asm/iommu.h>
33 #include <asm/hvcall.h>
34 #include <linux/dma-mapping.h>
35 #include <linux/interrupt.h>
36 #include "ibmvscsi.h"
37 #include "srp.h"
38
39 static char partition_name[97] = "UNKNOWN";
40 static unsigned int partition_number = -1;
41
42 /* ------------------------------------------------------------
43  * Routines for managing the command/response queue
44  */
45 /**
46  * ibmvscsi_handle_event: - Interrupt handler for crq events
47  * @irq:        number of irq to handle, not used
48  * @dev_instance: ibmvscsi_host_data of host that received interrupt
49  * @regs:       pt_regs with registers
50  *
51  * Disables interrupts and schedules srp_task
52  * Always returns IRQ_HANDLED
53  */
54 static irqreturn_t ibmvscsi_handle_event(int irq,
55                                          void *dev_instance,
56                                          struct pt_regs *regs)
57 {
58         struct ibmvscsi_host_data *hostdata =
59             (struct ibmvscsi_host_data *)dev_instance;
60         vio_disable_interrupts(to_vio_dev(hostdata->dev));
61         tasklet_schedule(&hostdata->srp_task);
62         return IRQ_HANDLED;
63 }
64
65 /**
66  * release_crq_queue: - Deallocates data and unregisters CRQ
67  * @queue:      crq_queue to initialize and register
68  * @host_data:  ibmvscsi_host_data of host
69  *
70  * Frees irq, deallocates a page for messages, unmaps dma, and unregisters
71  * the crq with the hypervisor.
72  */
73 void ibmvscsi_release_crq_queue(struct crq_queue *queue,
74                                 struct ibmvscsi_host_data *hostdata,
75                                 int max_requests)
76 {
77         long rc;
78         struct vio_dev *vdev = to_vio_dev(hostdata->dev);
79         free_irq(vdev->irq, (void *)hostdata);
80         tasklet_kill(&hostdata->srp_task);
81         do {
82                 rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
83         } while ((rc == H_Busy) || (H_isLongBusy(rc)));
84         dma_unmap_single(hostdata->dev,
85                          queue->msg_token,
86                          queue->size * sizeof(*queue->msgs), DMA_BIDIRECTIONAL);
87         free_page((unsigned long)queue->msgs);
88 }
89
90 /**
91  * crq_queue_next_crq: - Returns the next entry in message queue
92  * @queue:      crq_queue to use
93  *
94  * Returns pointer to next entry in queue, or NULL if there are no new 
95  * entried in the CRQ.
96  */
97 static struct viosrp_crq *crq_queue_next_crq(struct crq_queue *queue)
98 {
99         struct viosrp_crq *crq;
100         unsigned long flags;
101
102         spin_lock_irqsave(&queue->lock, flags);
103         crq = &queue->msgs[queue->cur];
104         if (crq->valid & 0x80) {
105                 if (++queue->cur == queue->size)
106                         queue->cur = 0;
107         } else
108                 crq = NULL;
109         spin_unlock_irqrestore(&queue->lock, flags);
110
111         return crq;
112 }
113
114 /**
115  * ibmvscsi_send_crq: - Send a CRQ
116  * @hostdata:   the adapter
117  * @word1:      the first 64 bits of the data
118  * @word2:      the second 64 bits of the data
119  */
120 int ibmvscsi_send_crq(struct ibmvscsi_host_data *hostdata, u64 word1, u64 word2)
121 {
122         struct vio_dev *vdev = to_vio_dev(hostdata->dev);
123
124         return plpar_hcall_norets(H_SEND_CRQ, vdev->unit_address, word1, word2);
125 }
126
127 /**
128  * ibmvscsi_task: - Process srps asynchronously
129  * @data:       ibmvscsi_host_data of host
130  */
131 static void ibmvscsi_task(void *data)
132 {
133         struct ibmvscsi_host_data *hostdata = (struct ibmvscsi_host_data *)data;
134         struct vio_dev *vdev = to_vio_dev(hostdata->dev);
135         struct viosrp_crq *crq;
136         int done = 0;
137
138         while (!done) {
139                 /* Pull all the valid messages off the CRQ */
140                 while ((crq = crq_queue_next_crq(&hostdata->queue)) != NULL) {
141                         ibmvscsi_handle_crq(crq, hostdata);
142                         crq->valid = 0x00;
143                 }
144
145                 vio_enable_interrupts(vdev);
146                 if ((crq = crq_queue_next_crq(&hostdata->queue)) != NULL) {
147                         vio_disable_interrupts(vdev);
148                         ibmvscsi_handle_crq(crq, hostdata);
149                         crq->valid = 0x00;
150                 } else {
151                         done = 1;
152                 }
153         }
154 }
155
156 static void gather_partition_info(void)
157 {
158         struct device_node *rootdn;
159
160         char *ppartition_name;
161         unsigned int *p_number_ptr;
162
163         /* Retrieve information about this partition */
164         rootdn = find_path_device("/");
165         if (!rootdn) {
166                 return;
167         }
168
169         ppartition_name =
170                 get_property(rootdn, "ibm,partition-name", NULL);
171         if (ppartition_name)
172                 strncpy(partition_name, ppartition_name,
173                                 sizeof(partition_name));
174         p_number_ptr =
175                 (unsigned int *)get_property(rootdn, "ibm,partition-no",
176                                              NULL);
177         if (p_number_ptr)
178                 partition_number = *p_number_ptr;
179 }
180
181 static void set_adapter_info(struct ibmvscsi_host_data *hostdata)
182 {
183         memset(&hostdata->madapter_info, 0x00,
184                         sizeof(hostdata->madapter_info));
185
186         printk(KERN_INFO "rpa_vscsi: SPR_VERSION: %s\n", SRP_VERSION);
187         strcpy(hostdata->madapter_info.srp_version, SRP_VERSION);
188
189         strncpy(hostdata->madapter_info.partition_name, partition_name,
190                         sizeof(hostdata->madapter_info.partition_name));
191
192         hostdata->madapter_info.partition_number = partition_number;
193
194         hostdata->madapter_info.mad_version = 1;
195         hostdata->madapter_info.os_type = 2;
196 }
197
198 /**
199  * initialize_crq_queue: - Initializes and registers CRQ with hypervisor
200  * @queue:      crq_queue to initialize and register
201  * @hostdata:   ibmvscsi_host_data of host
202  *
203  * Allocates a page for messages, maps it for dma, and registers
204  * the crq with the hypervisor.
205  * Returns zero on success.
206  */
207 int ibmvscsi_init_crq_queue(struct crq_queue *queue,
208                             struct ibmvscsi_host_data *hostdata,
209                             int max_requests)
210 {
211         int rc;
212         struct vio_dev *vdev = to_vio_dev(hostdata->dev);
213
214         queue->msgs = (struct viosrp_crq *)get_zeroed_page(GFP_KERNEL);
215
216         if (!queue->msgs)
217                 goto malloc_failed;
218         queue->size = PAGE_SIZE / sizeof(*queue->msgs);
219
220         queue->msg_token = dma_map_single(hostdata->dev, queue->msgs,
221                                           queue->size * sizeof(*queue->msgs),
222                                           DMA_BIDIRECTIONAL);
223
224         if (dma_mapping_error(queue->msg_token))
225                 goto map_failed;
226
227         gather_partition_info();
228         set_adapter_info(hostdata);
229
230         rc = plpar_hcall_norets(H_REG_CRQ,
231                                 vdev->unit_address,
232                                 queue->msg_token, PAGE_SIZE);
233         if (rc == 2) {
234                 /* Adapter is good, but other end is not ready */
235                 printk(KERN_WARNING "ibmvscsi: Partner adapter not ready\n");
236         } else if (rc != 0) {
237                 printk(KERN_WARNING "ibmvscsi: Error %d opening adapter\n", rc);
238                 goto reg_crq_failed;
239         }
240
241         if (request_irq(vdev->irq,
242                         ibmvscsi_handle_event,
243                         0, "ibmvscsi", (void *)hostdata) != 0) {
244                 printk(KERN_ERR "ibmvscsi: couldn't register irq 0x%x\n",
245                        vdev->irq);
246                 goto req_irq_failed;
247         }
248
249         rc = vio_enable_interrupts(vdev);
250         if (rc != 0) {
251                 printk(KERN_ERR "ibmvscsi:  Error %d enabling interrupts!!!\n",
252                        rc);
253                 goto req_irq_failed;
254         }
255
256         queue->cur = 0;
257         spin_lock_init(&queue->lock);
258
259         tasklet_init(&hostdata->srp_task, (void *)ibmvscsi_task,
260                      (unsigned long)hostdata);
261
262         return 0;
263
264       req_irq_failed:
265         do {
266                 rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
267         } while ((rc == H_Busy) || (H_isLongBusy(rc)));
268       reg_crq_failed:
269         dma_unmap_single(hostdata->dev,
270                          queue->msg_token,
271                          queue->size * sizeof(*queue->msgs), DMA_BIDIRECTIONAL);
272       map_failed:
273         free_page((unsigned long)queue->msgs);
274       malloc_failed:
275         return -1;
276 }
277
278 /**
279  * reset_crq_queue: - resets a crq after a failure
280  * @queue:      crq_queue to initialize and register
281  * @hostdata:   ibmvscsi_host_data of host
282  *
283  */
284 void ibmvscsi_reset_crq_queue(struct crq_queue *queue,
285                               struct ibmvscsi_host_data *hostdata)
286 {
287         int rc;
288         struct vio_dev *vdev = to_vio_dev(hostdata->dev);
289
290         /* Close the CRQ */
291         do {
292                 rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
293         } while ((rc == H_Busy) || (H_isLongBusy(rc)));
294
295         /* Clean out the queue */
296         memset(queue->msgs, 0x00, PAGE_SIZE);
297         queue->cur = 0;
298
299         set_adapter_info(hostdata);
300
301         /* And re-open it again */
302         rc = plpar_hcall_norets(H_REG_CRQ,
303                                 vdev->unit_address,
304                                 queue->msg_token, PAGE_SIZE);
305         if (rc == 2) {
306                 /* Adapter is good, but other end is not ready */
307                 printk(KERN_WARNING "ibmvscsi: Partner adapter not ready\n");
308         } else if (rc != 0) {
309                 printk(KERN_WARNING
310                        "ibmvscsi: couldn't register crq--rc 0x%x\n", rc);
311         }
312 }