xref: /openbmc/linux/drivers/s390/char/sclp_pci.c (revision 99a15348)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * PCI I/O adapter configuration related functions.
4  *
5  * Copyright IBM Corp. 2016
6  */
7 #define KMSG_COMPONENT "sclp_cmd"
8 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
9 
10 #include <linux/completion.h>
11 #include <linux/export.h>
12 #include <linux/mutex.h>
13 #include <linux/errno.h>
14 #include <linux/slab.h>
15 #include <linux/init.h>
16 #include <linux/err.h>
17 
18 #include <asm/sclp.h>
19 
20 #include "sclp.h"
21 
22 #define SCLP_CMDW_CONFIGURE_PCI			0x001a0001
23 #define SCLP_CMDW_DECONFIGURE_PCI		0x001b0001
24 
25 #define SCLP_ATYPE_PCI				2
26 
27 #define SCLP_ERRNOTIFY_AQ_RESET			0
28 #define SCLP_ERRNOTIFY_AQ_REPAIR		1
29 #define SCLP_ERRNOTIFY_AQ_INFO_LOG		2
30 
31 static DEFINE_MUTEX(sclp_pci_mutex);
32 static struct sclp_register sclp_pci_event = {
33 	.send_mask = EVTYP_ERRNOTIFY_MASK,
34 };
35 
36 struct err_notify_evbuf {
37 	struct evbuf_header header;
38 	u8 action;
39 	u8 atype;
40 	u32 fh;
41 	u32 fid;
42 	u8 data[];
43 } __packed;
44 
45 struct err_notify_sccb {
46 	struct sccb_header header;
47 	struct err_notify_evbuf evbuf;
48 } __packed;
49 
50 struct pci_cfg_sccb {
51 	struct sccb_header header;
52 	u8 atype;		/* adapter type */
53 	u8 reserved1;
54 	u16 reserved2;
55 	u32 aid;		/* adapter identifier */
56 } __packed;
57 
58 static int do_pci_configure(sclp_cmdw_t cmd, u32 fid)
59 {
60 	struct pci_cfg_sccb *sccb;
61 	int rc;
62 
63 	if (!SCLP_HAS_PCI_RECONFIG)
64 		return -EOPNOTSUPP;
65 
66 	sccb = (struct pci_cfg_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
67 	if (!sccb)
68 		return -ENOMEM;
69 
70 	sccb->header.length = PAGE_SIZE;
71 	sccb->atype = SCLP_ATYPE_PCI;
72 	sccb->aid = fid;
73 	rc = sclp_sync_request(cmd, sccb);
74 	if (rc)
75 		goto out;
76 	switch (sccb->header.response_code) {
77 	case 0x0020:
78 	case 0x0120:
79 		break;
80 	default:
81 		pr_warn("configure PCI I/O adapter failed: cmd=0x%08x  response=0x%04x\n",
82 			cmd, sccb->header.response_code);
83 		rc = -EIO;
84 		break;
85 	}
86 out:
87 	free_page((unsigned long) sccb);
88 	return rc;
89 }
90 
91 int sclp_pci_configure(u32 fid)
92 {
93 	return do_pci_configure(SCLP_CMDW_CONFIGURE_PCI, fid);
94 }
95 EXPORT_SYMBOL(sclp_pci_configure);
96 
97 int sclp_pci_deconfigure(u32 fid)
98 {
99 	return do_pci_configure(SCLP_CMDW_DECONFIGURE_PCI, fid);
100 }
101 EXPORT_SYMBOL(sclp_pci_deconfigure);
102 
103 static void sclp_pci_callback(struct sclp_req *req, void *data)
104 {
105 	struct completion *completion = data;
106 
107 	complete(completion);
108 }
109 
110 static int sclp_pci_check_report(struct zpci_report_error_header *report)
111 {
112 	if (report->version != 1)
113 		return -EINVAL;
114 
115 	switch (report->action) {
116 	case SCLP_ERRNOTIFY_AQ_RESET:
117 	case SCLP_ERRNOTIFY_AQ_REPAIR:
118 	case SCLP_ERRNOTIFY_AQ_INFO_LOG:
119 		break;
120 	default:
121 		return -EINVAL;
122 	}
123 
124 	if (report->length > (PAGE_SIZE - sizeof(struct err_notify_sccb)))
125 		return -EINVAL;
126 
127 	return 0;
128 }
129 
130 int sclp_pci_report(struct zpci_report_error_header *report, u32 fh, u32 fid)
131 {
132 	DECLARE_COMPLETION_ONSTACK(completion);
133 	struct err_notify_sccb *sccb;
134 	struct sclp_req req;
135 	int ret;
136 
137 	ret = sclp_pci_check_report(report);
138 	if (ret)
139 		return ret;
140 
141 	mutex_lock(&sclp_pci_mutex);
142 	ret = sclp_register(&sclp_pci_event);
143 	if (ret)
144 		goto out_unlock;
145 
146 	if (!(sclp_pci_event.sclp_receive_mask & EVTYP_ERRNOTIFY_MASK)) {
147 		ret = -EOPNOTSUPP;
148 		goto out_unregister;
149 	}
150 
151 	sccb = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
152 	if (!sccb) {
153 		ret = -ENOMEM;
154 		goto out_unregister;
155 	}
156 
157 	memset(&req, 0, sizeof(req));
158 	req.callback_data = &completion;
159 	req.callback = sclp_pci_callback;
160 	req.command = SCLP_CMDW_WRITE_EVENT_DATA;
161 	req.status = SCLP_REQ_FILLED;
162 	req.sccb = sccb;
163 
164 	sccb->evbuf.header.length = sizeof(sccb->evbuf) + report->length;
165 	sccb->evbuf.header.type = EVTYP_ERRNOTIFY;
166 	sccb->header.length = sizeof(sccb->header) + sccb->evbuf.header.length;
167 
168 	sccb->evbuf.action = report->action;
169 	sccb->evbuf.atype = SCLP_ATYPE_PCI;
170 	sccb->evbuf.fh = fh;
171 	sccb->evbuf.fid = fid;
172 
173 	memcpy(sccb->evbuf.data, report->data, report->length);
174 
175 	ret = sclp_add_request(&req);
176 	if (ret)
177 		goto out_free_req;
178 
179 	wait_for_completion(&completion);
180 	if (req.status != SCLP_REQ_DONE) {
181 		pr_warn("request failed (status=0x%02x)\n",
182 			req.status);
183 		ret = -EIO;
184 		goto out_free_req;
185 	}
186 
187 	if (sccb->header.response_code != 0x0020) {
188 		pr_warn("request failed with response code 0x%x\n",
189 			sccb->header.response_code);
190 		ret = -EIO;
191 	}
192 
193 out_free_req:
194 	free_page((unsigned long) sccb);
195 out_unregister:
196 	sclp_unregister(&sclp_pci_event);
197 out_unlock:
198 	mutex_unlock(&sclp_pci_mutex);
199 	return ret;
200 }
201