xref: /openbmc/linux/drivers/s390/char/sclp_early.c (revision 293d5b43)
1 /*
2  * SCLP early driver
3  *
4  * Copyright IBM Corp. 2013
5  */
6 
7 #define KMSG_COMPONENT "sclp_early"
8 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
9 
10 #include <linux/errno.h>
11 #include <asm/ctl_reg.h>
12 #include <asm/sclp.h>
13 #include <asm/ipl.h>
14 #include "sclp_sdias.h"
15 #include "sclp.h"
16 
17 #define SCLP_CMDW_READ_SCP_INFO		0x00020001
18 #define SCLP_CMDW_READ_SCP_INFO_FORCED	0x00120001
19 
20 struct read_info_sccb {
21 	struct	sccb_header header;	/* 0-7 */
22 	u16	rnmax;			/* 8-9 */
23 	u8	rnsize;			/* 10 */
24 	u8	_pad_11[16 - 11];	/* 11-15 */
25 	u16	ncpurl;			/* 16-17 */
26 	u16	cpuoff;			/* 18-19 */
27 	u8	_pad_20[24 - 20];	/* 20-23 */
28 	u8	loadparm[8];		/* 24-31 */
29 	u8	_pad_32[42 - 32];	/* 32-41 */
30 	u8	fac42;			/* 42 */
31 	u8	fac43;			/* 43 */
32 	u8	_pad_44[48 - 44];	/* 44-47 */
33 	u64	facilities;		/* 48-55 */
34 	u8	_pad_56[66 - 56];	/* 56-65 */
35 	u8	fac66;			/* 66 */
36 	u8	_pad_67[76 - 67];	/* 67-83 */
37 	u32	ibc;			/* 76-79 */
38 	u8	_pad80[84 - 80];	/* 80-83 */
39 	u8	fac84;			/* 84 */
40 	u8	fac85;			/* 85 */
41 	u8	_pad_86[91 - 86];	/* 86-90 */
42 	u8	flags;			/* 91 */
43 	u8	_pad_92[99 - 92];	/* 92-98 */
44 	u8	hamaxpow;		/* 99 */
45 	u32	rnsize2;		/* 100-103 */
46 	u64	rnmax2;			/* 104-111 */
47 	u8	_pad_112[116 - 112];	/* 112-115 */
48 	u8	fac116;			/* 116 */
49 	u8	fac117;			/* 117 */
50 	u8	_pad_118;		/* 118 */
51 	u8	fac119;			/* 119 */
52 	u16	hcpua;			/* 120-121 */
53 	u8	_pad_122[124 - 122];	/* 122-123 */
54 	u32	hmfai;			/* 124-127 */
55 	u8	_pad_128[4096 - 128];	/* 128-4095 */
56 } __packed __aligned(PAGE_SIZE);
57 
58 static char sccb_early[PAGE_SIZE] __aligned(PAGE_SIZE) __initdata;
59 static struct sclp_ipl_info sclp_ipl_info;
60 
61 struct sclp_info sclp;
62 EXPORT_SYMBOL(sclp);
63 
64 static int __init sclp_cmd_sync_early(sclp_cmdw_t cmd, void *sccb)
65 {
66 	int rc;
67 
68 	__ctl_set_bit(0, 9);
69 	rc = sclp_service_call(cmd, sccb);
70 	if (rc)
71 		goto out;
72 	__load_psw_mask(PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_MASK_EA |
73 			PSW_MASK_BA | PSW_MASK_EXT | PSW_MASK_WAIT);
74 	local_irq_disable();
75 out:
76 	/* Contents of the sccb might have changed. */
77 	barrier();
78 	__ctl_clear_bit(0, 9);
79 	return rc;
80 }
81 
82 static int __init sclp_read_info_early(struct read_info_sccb *sccb)
83 {
84 	int rc, i;
85 	sclp_cmdw_t commands[] = {SCLP_CMDW_READ_SCP_INFO_FORCED,
86 				  SCLP_CMDW_READ_SCP_INFO};
87 
88 	for (i = 0; i < ARRAY_SIZE(commands); i++) {
89 		do {
90 			memset(sccb, 0, sizeof(*sccb));
91 			sccb->header.length = sizeof(*sccb);
92 			sccb->header.function_code = 0x80;
93 			sccb->header.control_mask[2] = 0x80;
94 			rc = sclp_cmd_sync_early(commands[i], sccb);
95 		} while (rc == -EBUSY);
96 
97 		if (rc)
98 			break;
99 		if (sccb->header.response_code == 0x10)
100 			return 0;
101 		if (sccb->header.response_code != 0x1f0)
102 			break;
103 	}
104 	return -EIO;
105 }
106 
107 static void __init sclp_facilities_detect(struct read_info_sccb *sccb)
108 {
109 	struct sclp_core_entry *cpue;
110 	u16 boot_cpu_address, cpu;
111 
112 	if (sclp_read_info_early(sccb))
113 		return;
114 
115 	sclp.facilities = sccb->facilities;
116 	sclp.has_sprp = !!(sccb->fac84 & 0x02);
117 	sclp.has_core_type = !!(sccb->fac84 & 0x01);
118 	sclp.has_gsls = !!(sccb->fac85 & 0x80);
119 	sclp.has_64bscao = !!(sccb->fac116 & 0x80);
120 	sclp.has_cmma = !!(sccb->fac116 & 0x40);
121 	sclp.has_esca = !!(sccb->fac116 & 0x08);
122 	sclp.has_pfmfi = !!(sccb->fac117 & 0x40);
123 	sclp.has_ibs = !!(sccb->fac117 & 0x20);
124 	sclp.has_hvs = !!(sccb->fac119 & 0x80);
125 	if (sccb->fac85 & 0x02)
126 		S390_lowcore.machine_flags |= MACHINE_FLAG_ESOP;
127 	sclp.rnmax = sccb->rnmax ? sccb->rnmax : sccb->rnmax2;
128 	sclp.rzm = sccb->rnsize ? sccb->rnsize : sccb->rnsize2;
129 	sclp.rzm <<= 20;
130 	sclp.ibc = sccb->ibc;
131 
132 	if (sccb->hamaxpow && sccb->hamaxpow < 64)
133 		sclp.hamax = (1UL << sccb->hamaxpow) - 1;
134 	else
135 		sclp.hamax = U64_MAX;
136 
137 	if (!sccb->hcpua) {
138 		if (MACHINE_IS_VM)
139 			sclp.max_cores = 64;
140 		else
141 			sclp.max_cores = sccb->ncpurl;
142 	} else {
143 		sclp.max_cores = sccb->hcpua + 1;
144 	}
145 
146 	boot_cpu_address = stap();
147 	cpue = (void *)sccb + sccb->cpuoff;
148 	for (cpu = 0; cpu < sccb->ncpurl; cpue++, cpu++) {
149 		if (boot_cpu_address != cpue->core_id)
150 			continue;
151 		sclp.has_siif = cpue->siif;
152 		sclp.has_sigpif = cpue->sigpif;
153 		sclp.has_sief2 = cpue->sief2;
154 		sclp.has_gpere = cpue->gpere;
155 		sclp.has_ib = cpue->ib;
156 		sclp.has_cei = cpue->cei;
157 		sclp.has_skey = cpue->skey;
158 		break;
159 	}
160 
161 	/* Save IPL information */
162 	sclp_ipl_info.is_valid = 1;
163 	if (sccb->flags & 0x2)
164 		sclp_ipl_info.has_dump = 1;
165 	memcpy(&sclp_ipl_info.loadparm, &sccb->loadparm, LOADPARM_LEN);
166 
167 	sclp.mtid = (sccb->fac42 & 0x80) ? (sccb->fac42 & 31) : 0;
168 	sclp.mtid_cp = (sccb->fac42 & 0x80) ? (sccb->fac43 & 31) : 0;
169 	sclp.mtid_prev = (sccb->fac42 & 0x80) ? (sccb->fac66 & 31) : 0;
170 
171 	sclp.hmfai = sccb->hmfai;
172 }
173 
174 /*
175  * This function will be called after sclp_facilities_detect(), which gets
176  * called from early.c code. The sclp_facilities_detect() function retrieves
177  * and saves the IPL information.
178  */
179 void __init sclp_get_ipl_info(struct sclp_ipl_info *info)
180 {
181 	*info = sclp_ipl_info;
182 }
183 
184 static int __init sclp_cmd_early(sclp_cmdw_t cmd, void *sccb)
185 {
186 	int rc;
187 
188 	do {
189 		rc = sclp_cmd_sync_early(cmd, sccb);
190 	} while (rc == -EBUSY);
191 
192 	if (rc)
193 		return -EIO;
194 	if (((struct sccb_header *) sccb)->response_code != 0x0020)
195 		return -EIO;
196 	return 0;
197 }
198 
199 static void __init sccb_init_eq_size(struct sdias_sccb *sccb)
200 {
201 	memset(sccb, 0, sizeof(*sccb));
202 
203 	sccb->hdr.length = sizeof(*sccb);
204 	sccb->evbuf.hdr.length = sizeof(struct sdias_evbuf);
205 	sccb->evbuf.hdr.type = EVTYP_SDIAS;
206 	sccb->evbuf.event_qual = SDIAS_EQ_SIZE;
207 	sccb->evbuf.data_id = SDIAS_DI_FCP_DUMP;
208 	sccb->evbuf.event_id = 4712;
209 	sccb->evbuf.dbs = 1;
210 }
211 
212 static int __init sclp_set_event_mask(struct init_sccb *sccb,
213 				      unsigned long receive_mask,
214 				      unsigned long send_mask)
215 {
216 	memset(sccb, 0, sizeof(*sccb));
217 	sccb->header.length = sizeof(*sccb);
218 	sccb->mask_length = sizeof(sccb_mask_t);
219 	sccb->receive_mask = receive_mask;
220 	sccb->send_mask = send_mask;
221 	return sclp_cmd_early(SCLP_CMDW_WRITE_EVENT_MASK, sccb);
222 }
223 
224 static long __init sclp_hsa_size_init(struct sdias_sccb *sccb)
225 {
226 	sccb_init_eq_size(sccb);
227 	if (sclp_cmd_early(SCLP_CMDW_WRITE_EVENT_DATA, sccb))
228 		return -EIO;
229 	if (sccb->evbuf.blk_cnt == 0)
230 		return 0;
231 	return (sccb->evbuf.blk_cnt - 1) * PAGE_SIZE;
232 }
233 
234 static long __init sclp_hsa_copy_wait(struct sccb_header *sccb)
235 {
236 	memset(sccb, 0, PAGE_SIZE);
237 	sccb->length = PAGE_SIZE;
238 	if (sclp_cmd_early(SCLP_CMDW_READ_EVENT_DATA, sccb))
239 		return -EIO;
240 	if (((struct sdias_sccb *) sccb)->evbuf.blk_cnt == 0)
241 		return 0;
242 	return (((struct sdias_sccb *) sccb)->evbuf.blk_cnt - 1) * PAGE_SIZE;
243 }
244 
245 static void __init sclp_hsa_size_detect(void *sccb)
246 {
247 	long size;
248 
249 	/* First try synchronous interface (LPAR) */
250 	if (sclp_set_event_mask(sccb, 0, 0x40000010))
251 		return;
252 	size = sclp_hsa_size_init(sccb);
253 	if (size < 0)
254 		return;
255 	if (size != 0)
256 		goto out;
257 	/* Then try asynchronous interface (z/VM) */
258 	if (sclp_set_event_mask(sccb, 0x00000010, 0x40000010))
259 		return;
260 	size = sclp_hsa_size_init(sccb);
261 	if (size < 0)
262 		return;
263 	size = sclp_hsa_copy_wait(sccb);
264 	if (size < 0)
265 		return;
266 out:
267 	sclp.hsa_size = size;
268 }
269 
270 static unsigned int __init sclp_con_check_linemode(struct init_sccb *sccb)
271 {
272 	if (!(sccb->sclp_send_mask & EVTYP_OPCMD_MASK))
273 		return 0;
274 	if (!(sccb->sclp_receive_mask & (EVTYP_MSG_MASK | EVTYP_PMSGCMD_MASK)))
275 		return 0;
276 	return 1;
277 }
278 
279 static void __init sclp_console_detect(struct init_sccb *sccb)
280 {
281 	if (sccb->header.response_code != 0x20)
282 		return;
283 
284 	if (sccb->sclp_send_mask & EVTYP_VT220MSG_MASK)
285 		sclp.has_vt220 = 1;
286 
287 	if (sclp_con_check_linemode(sccb))
288 		sclp.has_linemode = 1;
289 }
290 
291 void __init sclp_early_detect(void)
292 {
293 	void *sccb = &sccb_early;
294 
295 	sclp_facilities_detect(sccb);
296 	sclp_hsa_size_detect(sccb);
297 
298 	/* Turn off SCLP event notifications.  Also save remote masks in the
299 	 * sccb.  These are sufficient to detect sclp console capabilities.
300 	 */
301 	sclp_set_event_mask(sccb, 0, 0);
302 	sclp_console_detect(sccb);
303 }
304