ibmvscsi: driver enablement for CMO
[linux-2.6.git] / drivers / scsi / ibmvscsi / iseries_vscsi.c
1 /* ------------------------------------------------------------
2  * iSeries_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  *          Dave Boutcher (sleddog@us.ibm.com)
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
21  * USA
22  *
23  * ------------------------------------------------------------
24  * iSeries-specific functions of the SCSI host adapter for Virtual I/O devices
25  *
26  * This driver allows the Linux SCSI peripheral drivers to directly
27  * access devices in the hosting partition, either on an iSeries
28  * hypervisor system or a converged hypervisor system.
29  */
30
31 #include <asm/iseries/vio.h>
32 #include <asm/iseries/hv_lp_event.h>
33 #include <asm/iseries/hv_types.h>
34 #include <asm/iseries/hv_lp_config.h>
35 #include <asm/vio.h>
36 #include <linux/device.h>
37 #include "ibmvscsi.h"
38
39 /* global variables */
40 static struct ibmvscsi_host_data *single_host_data;
41
42 /* ------------------------------------------------------------
43  * Routines for direct interpartition interaction
44  */
45 struct srp_lp_event {
46         struct HvLpEvent lpevt; /* 0x00-0x17          */
47         u32 reserved1;          /* 0x18-0x1B; unused  */
48         u16 version;            /* 0x1C-0x1D; unused  */
49         u16 subtype_rc;         /* 0x1E-0x1F; unused  */
50         struct viosrp_crq crq;  /* 0x20-0x3F          */
51 };
52
53 /** 
54  * standard interface for handling logical partition events.
55  */
56 static void iseriesvscsi_handle_event(struct HvLpEvent *lpevt)
57 {
58         struct srp_lp_event *evt = (struct srp_lp_event *)lpevt;
59
60         if (!evt) {
61                 printk(KERN_ERR "ibmvscsi: received null event\n");
62                 return;
63         }
64
65         if (single_host_data == NULL) {
66                 printk(KERN_ERR
67                        "ibmvscsi: received event, no adapter present\n");
68                 return;
69         }
70
71         ibmvscsi_handle_crq(&evt->crq, single_host_data);
72 }
73
74 /* ------------------------------------------------------------
75  * Routines for driver initialization
76  */
77 static int iseriesvscsi_init_crq_queue(struct crq_queue *queue,
78                                        struct ibmvscsi_host_data *hostdata,
79                                        int max_requests)
80 {
81         int rc;
82
83         single_host_data = hostdata;
84         rc = viopath_open(viopath_hostLp, viomajorsubtype_scsi, max_requests);
85         if (rc < 0) {
86                 printk("viopath_open failed with rc %d in open_event_path\n",
87                        rc);
88                 goto viopath_open_failed;
89         }
90
91         rc = vio_setHandler(viomajorsubtype_scsi, iseriesvscsi_handle_event);
92         if (rc < 0) {
93                 printk("vio_setHandler failed with rc %d in open_event_path\n",
94                        rc);
95                 goto vio_setHandler_failed;
96         }
97         return 0;
98
99       vio_setHandler_failed:
100         viopath_close(viopath_hostLp, viomajorsubtype_scsi, max_requests);
101       viopath_open_failed:
102         return -1;
103 }
104
105 static void iseriesvscsi_release_crq_queue(struct crq_queue *queue,
106                                            struct ibmvscsi_host_data *hostdata,
107                                            int max_requests)
108 {
109         vio_clearHandler(viomajorsubtype_scsi);
110         viopath_close(viopath_hostLp, viomajorsubtype_scsi, max_requests);
111 }
112
113 /**
114  * reset_crq_queue: - resets a crq after a failure
115  * @queue:      crq_queue to initialize and register
116  * @hostdata:   ibmvscsi_host_data of host
117  *
118  * no-op for iSeries
119  */
120 static int iseriesvscsi_reset_crq_queue(struct crq_queue *queue,
121                                         struct ibmvscsi_host_data *hostdata)
122 {
123         return 0;
124 }
125
126 /**
127  * reenable_crq_queue: - reenables a crq after a failure
128  * @queue:      crq_queue to initialize and register
129  * @hostdata:   ibmvscsi_host_data of host
130  *
131  * no-op for iSeries
132  */
133 static int iseriesvscsi_reenable_crq_queue(struct crq_queue *queue,
134                                            struct ibmvscsi_host_data *hostdata)
135 {
136         return 0;
137 }
138
139 /**
140  * iseriesvscsi_send_crq: - Send a CRQ
141  * @hostdata:   the adapter
142  * @word1:      the first 64 bits of the data
143  * @word2:      the second 64 bits of the data
144  */
145 static int iseriesvscsi_send_crq(struct ibmvscsi_host_data *hostdata,
146                                  u64 word1, u64 word2)
147 {
148         single_host_data = hostdata;
149         return HvCallEvent_signalLpEventFast(viopath_hostLp,
150                                              HvLpEvent_Type_VirtualIo,
151                                              viomajorsubtype_scsi,
152                                              HvLpEvent_AckInd_NoAck,
153                                              HvLpEvent_AckType_ImmediateAck,
154                                              viopath_sourceinst(viopath_hostLp),
155                                              viopath_targetinst(viopath_hostLp),
156                                              0,
157                                              VIOVERSION << 16, word1, word2, 0,
158                                              0);
159 }
160
161 struct ibmvscsi_ops iseriesvscsi_ops = {
162         .init_crq_queue = iseriesvscsi_init_crq_queue,
163         .release_crq_queue = iseriesvscsi_release_crq_queue,
164         .reset_crq_queue = iseriesvscsi_reset_crq_queue,
165         .reenable_crq_queue = iseriesvscsi_reenable_crq_queue,
166         .send_crq = iseriesvscsi_send_crq,
167 };