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 */
40static struct ibmvscsi_host_data *single_host_data;
41
42/* ------------------------------------------------------------
43 * Routines for direct interpartition interaction
44 */
45struct 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 */
56static void ibmvscsi_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 */
77int ibmvscsi_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, ibmvscsi_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
105void ibmvscsi_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 */
120int ibmvscsi_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 */
133int ibmvscsi_reenable_crq_queue(struct crq_queue *queue,
134				struct ibmvscsi_host_data *hostdata)
135{
136	return 0;
137}
138
139/**
140 * ibmvscsi_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 */
145int ibmvscsi_send_crq(struct ibmvscsi_host_data *hostdata, u64 word1, u64 word2)
146{
147	single_host_data = hostdata;
148	return HvCallEvent_signalLpEventFast(viopath_hostLp,
149					     HvLpEvent_Type_VirtualIo,
150					     viomajorsubtype_scsi,
151					     HvLpEvent_AckInd_NoAck,
152					     HvLpEvent_AckType_ImmediateAck,
153					     viopath_sourceinst(viopath_hostLp),
154					     viopath_targetinst(viopath_hostLp),
155					     0,
156					     VIOVERSION << 16, word1, word2, 0,
157					     0);
158}
159