xref: /openbmc/linux/drivers/s390/char/sclp_early.c (revision 3d3337de)
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 <asm/ctl_reg.h>
11 #include <asm/sclp.h>
12 #include <asm/ipl.h>
13 #include "sclp_sdias.h"
14 #include "sclp.h"
15 
16 #define SCLP_CMDW_READ_SCP_INFO		0x00020001
17 #define SCLP_CMDW_READ_SCP_INFO_FORCED	0x00120001
18 
19 struct read_info_sccb {
20 	struct	sccb_header header;	/* 0-7 */
21 	u16	rnmax;			/* 8-9 */
22 	u8	rnsize;			/* 10 */
23 	u8	_pad_11[16 - 11];	/* 11-15 */
24 	u16	ncpurl;			/* 16-17 */
25 	u16	cpuoff;			/* 18-19 */
26 	u8	_pad_20[24 - 20];	/* 20-23 */
27 	u8	loadparm[8];		/* 24-31 */
28 	u8	_pad_32[42 - 32];	/* 32-41 */
29 	u8	fac42;			/* 42 */
30 	u8	fac43;			/* 43 */
31 	u8	_pad_44[48 - 44];	/* 44-47 */
32 	u64	facilities;		/* 48-55 */
33 	u8	_pad_56[66 - 56];	/* 56-65 */
34 	u8	fac66;			/* 66 */
35 	u8	_pad_67[76 - 67];	/* 67-83 */
36 	u32	ibc;			/* 76-79 */
37 	u8	_pad80[84 - 80];	/* 80-83 */
38 	u8	fac84;			/* 84 */
39 	u8	fac85;			/* 85 */
40 	u8	_pad_86[91 - 86];	/* 86-90 */
41 	u8	flags;			/* 91 */
42 	u8	_pad_92[100 - 92];	/* 92-99 */
43 	u32	rnsize2;		/* 100-103 */
44 	u64	rnmax2;			/* 104-111 */
45 	u8	_pad_112[120 - 112];	/* 112-119 */
46 	u16	hcpua;			/* 120-121 */
47 	u8	_pad_122[4096 - 122];	/* 122-4095 */
48 } __packed __aligned(PAGE_SIZE);
49 
50 static char sccb_early[PAGE_SIZE] __aligned(PAGE_SIZE) __initdata;
51 static unsigned int sclp_con_has_vt220 __initdata;
52 static unsigned int sclp_con_has_linemode __initdata;
53 static unsigned long sclp_hsa_size;
54 static unsigned int sclp_max_cpu;
55 static struct sclp_ipl_info sclp_ipl_info;
56 static unsigned char sclp_siif;
57 static unsigned char sclp_sigpif;
58 static u32 sclp_ibc;
59 static unsigned int sclp_mtid;
60 static unsigned int sclp_mtid_cp;
61 static unsigned int sclp_mtid_max;
62 static unsigned int sclp_mtid_prev;
63 
64 u64 sclp_facilities;
65 u8 sclp_fac84;
66 unsigned long long sclp_rzm;
67 unsigned long long sclp_rnmax;
68 
69 static int __init sclp_cmd_sync_early(sclp_cmdw_t cmd, void *sccb)
70 {
71 	int rc;
72 
73 	__ctl_set_bit(0, 9);
74 	rc = sclp_service_call(cmd, sccb);
75 	if (rc)
76 		goto out;
77 	__load_psw_mask(PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_MASK_EA |
78 			PSW_MASK_BA | PSW_MASK_EXT | PSW_MASK_WAIT);
79 	local_irq_disable();
80 out:
81 	/* Contents of the sccb might have changed. */
82 	barrier();
83 	__ctl_clear_bit(0, 9);
84 	return rc;
85 }
86 
87 static int __init sclp_read_info_early(struct read_info_sccb *sccb)
88 {
89 	int rc, i;
90 	sclp_cmdw_t commands[] = {SCLP_CMDW_READ_SCP_INFO_FORCED,
91 				  SCLP_CMDW_READ_SCP_INFO};
92 
93 	for (i = 0; i < ARRAY_SIZE(commands); i++) {
94 		do {
95 			memset(sccb, 0, sizeof(*sccb));
96 			sccb->header.length = sizeof(*sccb);
97 			sccb->header.function_code = 0x80;
98 			sccb->header.control_mask[2] = 0x80;
99 			rc = sclp_cmd_sync_early(commands[i], sccb);
100 		} while (rc == -EBUSY);
101 
102 		if (rc)
103 			break;
104 		if (sccb->header.response_code == 0x10)
105 			return 0;
106 		if (sccb->header.response_code != 0x1f0)
107 			break;
108 	}
109 	return -EIO;
110 }
111 
112 static void __init sclp_facilities_detect(struct read_info_sccb *sccb)
113 {
114 	struct sclp_cpu_entry *cpue;
115 	u16 boot_cpu_address, cpu;
116 
117 	if (sclp_read_info_early(sccb))
118 		return;
119 
120 	sclp_facilities = sccb->facilities;
121 	sclp_fac84 = sccb->fac84;
122 	if (sccb->fac85 & 0x02)
123 		S390_lowcore.machine_flags |= MACHINE_FLAG_ESOP;
124 	sclp_rnmax = sccb->rnmax ? sccb->rnmax : sccb->rnmax2;
125 	sclp_rzm = sccb->rnsize ? sccb->rnsize : sccb->rnsize2;
126 	sclp_rzm <<= 20;
127 	sclp_ibc = sccb->ibc;
128 
129 	if (!sccb->hcpua) {
130 		if (MACHINE_IS_VM)
131 			sclp_max_cpu = 64;
132 		else
133 			sclp_max_cpu = sccb->ncpurl;
134 	} else {
135 		sclp_max_cpu = sccb->hcpua + 1;
136 	}
137 
138 	boot_cpu_address = stap();
139 	cpue = (void *)sccb + sccb->cpuoff;
140 	for (cpu = 0; cpu < sccb->ncpurl; cpue++, cpu++) {
141 		if (boot_cpu_address != cpue->core_id)
142 			continue;
143 		sclp_siif = cpue->siif;
144 		sclp_sigpif = cpue->sigpif;
145 		break;
146 	}
147 
148 	/* Save IPL information */
149 	sclp_ipl_info.is_valid = 1;
150 	if (sccb->flags & 0x2)
151 		sclp_ipl_info.has_dump = 1;
152 	memcpy(&sclp_ipl_info.loadparm, &sccb->loadparm, LOADPARM_LEN);
153 
154 	sclp_mtid = (sccb->fac42 & 0x80) ? (sccb->fac42 & 31) : 0;
155 	sclp_mtid_cp = (sccb->fac42 & 0x80) ? (sccb->fac43 & 31) : 0;
156 	sclp_mtid_max = max(sclp_mtid, sclp_mtid_cp);
157 	sclp_mtid_prev = (sccb->fac42 & 0x80) ? (sccb->fac66 & 31) : 0;
158 }
159 
160 bool __init sclp_has_linemode(void)
161 {
162 	return !!sclp_con_has_linemode;
163 }
164 
165 bool __init sclp_has_vt220(void)
166 {
167 	return !!sclp_con_has_vt220;
168 }
169 
170 unsigned long long sclp_get_rnmax(void)
171 {
172 	return sclp_rnmax;
173 }
174 
175 unsigned long long sclp_get_rzm(void)
176 {
177 	return sclp_rzm;
178 }
179 
180 unsigned int sclp_get_max_cpu(void)
181 {
182 	return sclp_max_cpu;
183 }
184 
185 int sclp_has_siif(void)
186 {
187 	return sclp_siif;
188 }
189 EXPORT_SYMBOL(sclp_has_siif);
190 
191 int sclp_has_sigpif(void)
192 {
193 	return sclp_sigpif;
194 }
195 EXPORT_SYMBOL(sclp_has_sigpif);
196 
197 unsigned int sclp_get_ibc(void)
198 {
199 	return sclp_ibc;
200 }
201 EXPORT_SYMBOL(sclp_get_ibc);
202 
203 unsigned int sclp_get_mtid(u8 cpu_type)
204 {
205 	return cpu_type ? sclp_mtid : sclp_mtid_cp;
206 }
207 
208 unsigned int sclp_get_mtid_max(void)
209 {
210 	return sclp_mtid_max;
211 }
212 
213 unsigned int sclp_get_mtid_prev(void)
214 {
215 	return sclp_mtid_prev;
216 }
217 
218 /*
219  * This function will be called after sclp_facilities_detect(), which gets
220  * called from early.c code. The sclp_facilities_detect() function retrieves
221  * and saves the IPL information.
222  */
223 void __init sclp_get_ipl_info(struct sclp_ipl_info *info)
224 {
225 	*info = sclp_ipl_info;
226 }
227 
228 static int __init sclp_cmd_early(sclp_cmdw_t cmd, void *sccb)
229 {
230 	int rc;
231 
232 	do {
233 		rc = sclp_cmd_sync_early(cmd, sccb);
234 	} while (rc == -EBUSY);
235 
236 	if (rc)
237 		return -EIO;
238 	if (((struct sccb_header *) sccb)->response_code != 0x0020)
239 		return -EIO;
240 	return 0;
241 }
242 
243 static void __init sccb_init_eq_size(struct sdias_sccb *sccb)
244 {
245 	memset(sccb, 0, sizeof(*sccb));
246 
247 	sccb->hdr.length = sizeof(*sccb);
248 	sccb->evbuf.hdr.length = sizeof(struct sdias_evbuf);
249 	sccb->evbuf.hdr.type = EVTYP_SDIAS;
250 	sccb->evbuf.event_qual = SDIAS_EQ_SIZE;
251 	sccb->evbuf.data_id = SDIAS_DI_FCP_DUMP;
252 	sccb->evbuf.event_id = 4712;
253 	sccb->evbuf.dbs = 1;
254 }
255 
256 static int __init sclp_set_event_mask(struct init_sccb *sccb,
257 				      unsigned long receive_mask,
258 				      unsigned long send_mask)
259 {
260 	memset(sccb, 0, sizeof(*sccb));
261 	sccb->header.length = sizeof(*sccb);
262 	sccb->mask_length = sizeof(sccb_mask_t);
263 	sccb->receive_mask = receive_mask;
264 	sccb->send_mask = send_mask;
265 	return sclp_cmd_early(SCLP_CMDW_WRITE_EVENT_MASK, sccb);
266 }
267 
268 static long __init sclp_hsa_size_init(struct sdias_sccb *sccb)
269 {
270 	sccb_init_eq_size(sccb);
271 	if (sclp_cmd_early(SCLP_CMDW_WRITE_EVENT_DATA, sccb))
272 		return -EIO;
273 	if (sccb->evbuf.blk_cnt == 0)
274 		return 0;
275 	return (sccb->evbuf.blk_cnt - 1) * PAGE_SIZE;
276 }
277 
278 static long __init sclp_hsa_copy_wait(struct sccb_header *sccb)
279 {
280 	memset(sccb, 0, PAGE_SIZE);
281 	sccb->length = PAGE_SIZE;
282 	if (sclp_cmd_early(SCLP_CMDW_READ_EVENT_DATA, sccb))
283 		return -EIO;
284 	if (((struct sdias_sccb *) sccb)->evbuf.blk_cnt == 0)
285 		return 0;
286 	return (((struct sdias_sccb *) sccb)->evbuf.blk_cnt - 1) * PAGE_SIZE;
287 }
288 
289 unsigned long sclp_get_hsa_size(void)
290 {
291 	return sclp_hsa_size;
292 }
293 
294 static void __init sclp_hsa_size_detect(void *sccb)
295 {
296 	long size;
297 
298 	/* First try synchronous interface (LPAR) */
299 	if (sclp_set_event_mask(sccb, 0, 0x40000010))
300 		return;
301 	size = sclp_hsa_size_init(sccb);
302 	if (size < 0)
303 		return;
304 	if (size != 0)
305 		goto out;
306 	/* Then try asynchronous interface (z/VM) */
307 	if (sclp_set_event_mask(sccb, 0x00000010, 0x40000010))
308 		return;
309 	size = sclp_hsa_size_init(sccb);
310 	if (size < 0)
311 		return;
312 	size = sclp_hsa_copy_wait(sccb);
313 	if (size < 0)
314 		return;
315 out:
316 	sclp_hsa_size = size;
317 }
318 
319 static unsigned int __init sclp_con_check_linemode(struct init_sccb *sccb)
320 {
321 	if (!(sccb->sclp_send_mask & EVTYP_OPCMD_MASK))
322 		return 0;
323 	if (!(sccb->sclp_receive_mask & (EVTYP_MSG_MASK | EVTYP_PMSGCMD_MASK)))
324 		return 0;
325 	return 1;
326 }
327 
328 static void __init sclp_console_detect(struct init_sccb *sccb)
329 {
330 	if (sccb->header.response_code != 0x20)
331 		return;
332 
333 	if (sccb->sclp_send_mask & EVTYP_VT220MSG_MASK)
334 		sclp_con_has_vt220 = 1;
335 
336 	if (sclp_con_check_linemode(sccb))
337 		sclp_con_has_linemode = 1;
338 }
339 
340 void __init sclp_early_detect(void)
341 {
342 	void *sccb = &sccb_early;
343 
344 	sclp_facilities_detect(sccb);
345 	sclp_hsa_size_detect(sccb);
346 
347 	/* Turn off SCLP event notifications.  Also save remote masks in the
348 	 * sccb.  These are sufficient to detect sclp console capabilities.
349 	 */
350 	sclp_set_event_mask(sccb, 0, 0);
351 	sclp_console_detect(sccb);
352 }
353