xref: /openbmc/linux/drivers/s390/char/sclp_pci.c (revision 7587eb18)
1 /*
2  * PCI I/O adapter configuration related functions.
3  *
4  * Copyright IBM Corp. 2016
5  */
6 #define KMSG_COMPONENT "sclp_cmd"
7 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
8 
9 #include <linux/completion.h>
10 #include <linux/export.h>
11 #include <linux/mutex.h>
12 #include <linux/errno.h>
13 #include <linux/slab.h>
14 #include <linux/init.h>
15 #include <linux/err.h>
16 
17 #include <asm/sclp.h>
18 
19 #include "sclp.h"
20 
21 #define SCLP_CMDW_CONFIGURE_PCI			0x001a0001
22 #define SCLP_CMDW_DECONFIGURE_PCI		0x001b0001
23 
24 #define SCLP_ATYPE_PCI				2
25 
26 #define SCLP_ERRNOTIFY_AQ_REPAIR		1
27 #define SCLP_ERRNOTIFY_AQ_INFO_LOG		2
28 
29 static DEFINE_MUTEX(sclp_pci_mutex);
30 static struct sclp_register sclp_pci_event = {
31 	.send_mask = EVTYP_ERRNOTIFY_MASK,
32 };
33 
34 struct err_notify_evbuf {
35 	struct evbuf_header header;
36 	u8 action;
37 	u8 atype;
38 	u32 fh;
39 	u32 fid;
40 	u8 data[0];
41 } __packed;
42 
43 struct err_notify_sccb {
44 	struct sccb_header header;
45 	struct err_notify_evbuf evbuf;
46 } __packed;
47 
48 struct pci_cfg_sccb {
49 	struct sccb_header header;
50 	u8 atype;		/* adapter type */
51 	u8 reserved1;
52 	u16 reserved2;
53 	u32 aid;		/* adapter identifier */
54 } __packed;
55 
56 static int do_pci_configure(sclp_cmdw_t cmd, u32 fid)
57 {
58 	struct pci_cfg_sccb *sccb;
59 	int rc;
60 
61 	if (!SCLP_HAS_PCI_RECONFIG)
62 		return -EOPNOTSUPP;
63 
64 	sccb = (struct pci_cfg_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
65 	if (!sccb)
66 		return -ENOMEM;
67 
68 	sccb->header.length = PAGE_SIZE;
69 	sccb->atype = SCLP_ATYPE_PCI;
70 	sccb->aid = fid;
71 	rc = sclp_sync_request(cmd, sccb);
72 	if (rc)
73 		goto out;
74 	switch (sccb->header.response_code) {
75 	case 0x0020:
76 	case 0x0120:
77 		break;
78 	default:
79 		pr_warn("configure PCI I/O adapter failed: cmd=0x%08x  response=0x%04x\n",
80 			cmd, sccb->header.response_code);
81 		rc = -EIO;
82 		break;
83 	}
84 out:
85 	free_page((unsigned long) sccb);
86 	return rc;
87 }
88 
89 int sclp_pci_configure(u32 fid)
90 {
91 	return do_pci_configure(SCLP_CMDW_CONFIGURE_PCI, fid);
92 }
93 EXPORT_SYMBOL(sclp_pci_configure);
94 
95 int sclp_pci_deconfigure(u32 fid)
96 {
97 	return do_pci_configure(SCLP_CMDW_DECONFIGURE_PCI, fid);
98 }
99 EXPORT_SYMBOL(sclp_pci_deconfigure);
100 
101 static void sclp_pci_callback(struct sclp_req *req, void *data)
102 {
103 	struct completion *completion = data;
104 
105 	complete(completion);
106 }
107 
108 static int sclp_pci_check_report(struct zpci_report_error_header *report)
109 {
110 	if (report->version != 1)
111 		return -EINVAL;
112 
113 	if (report->action != SCLP_ERRNOTIFY_AQ_REPAIR &&
114 	    report->action != SCLP_ERRNOTIFY_AQ_INFO_LOG)
115 		return -EINVAL;
116 
117 	if (report->length > (PAGE_SIZE - sizeof(struct err_notify_sccb)))
118 		return -EINVAL;
119 
120 	return 0;
121 }
122 
123 int sclp_pci_report(struct zpci_report_error_header *report, u32 fh, u32 fid)
124 {
125 	DECLARE_COMPLETION_ONSTACK(completion);
126 	struct err_notify_sccb *sccb;
127 	struct sclp_req req;
128 	int ret;
129 
130 	ret = sclp_pci_check_report(report);
131 	if (ret)
132 		return ret;
133 
134 	mutex_lock(&sclp_pci_mutex);
135 	ret = sclp_register(&sclp_pci_event);
136 	if (ret)
137 		goto out_unlock;
138 
139 	if (!(sclp_pci_event.sclp_receive_mask & EVTYP_ERRNOTIFY_MASK)) {
140 		ret = -EOPNOTSUPP;
141 		goto out_unregister;
142 	}
143 
144 	sccb = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
145 	if (!sccb) {
146 		ret = -ENOMEM;
147 		goto out_unregister;
148 	}
149 
150 	memset(&req, 0, sizeof(req));
151 	req.callback_data = &completion;
152 	req.callback = sclp_pci_callback;
153 	req.command = SCLP_CMDW_WRITE_EVENT_DATA;
154 	req.status = SCLP_REQ_FILLED;
155 	req.sccb = sccb;
156 
157 	sccb->evbuf.header.length = sizeof(sccb->evbuf) + report->length;
158 	sccb->evbuf.header.type = EVTYP_ERRNOTIFY;
159 	sccb->header.length = sizeof(sccb->header) + sccb->evbuf.header.length;
160 
161 	sccb->evbuf.action = report->action;
162 	sccb->evbuf.atype = SCLP_ATYPE_PCI;
163 	sccb->evbuf.fh = fh;
164 	sccb->evbuf.fid = fid;
165 
166 	memcpy(sccb->evbuf.data, report->data, report->length);
167 
168 	ret = sclp_add_request(&req);
169 	if (ret)
170 		goto out_free_req;
171 
172 	wait_for_completion(&completion);
173 	if (req.status != SCLP_REQ_DONE) {
174 		pr_warn("request failed (status=0x%02x)\n",
175 			req.status);
176 		ret = -EIO;
177 		goto out_free_req;
178 	}
179 
180 	if (sccb->header.response_code != 0x0020) {
181 		pr_warn("request failed with response code 0x%x\n",
182 			sccb->header.response_code);
183 		ret = -EIO;
184 	}
185 
186 out_free_req:
187 	free_page((unsigned long) sccb);
188 out_unregister:
189 	sclp_unregister(&sclp_pci_event);
190 out_unlock:
191 	mutex_unlock(&sclp_pci_mutex);
192 	return ret;
193 }
194