1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright IBM Corp. 2015
4 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
5 */
6
7 #include <linux/kernel.h>
8 #include <asm/processor.h>
9 #include <asm/lowcore.h>
10 #include <asm/ebcdic.h>
11 #include <asm/irq.h>
12 #include <asm/sections.h>
13 #include <asm/physmem_info.h>
14 #include <asm/facility.h>
15 #include "sclp.h"
16 #include "sclp_rw.h"
17
18 static struct read_info_sccb __bootdata(sclp_info_sccb);
19 static int __bootdata(sclp_info_sccb_valid);
20 char *__bootdata_preserved(sclp_early_sccb);
21 int sclp_init_state = sclp_init_state_uninitialized;
22 /*
23 * Used to keep track of the size of the event masks. Qemu until version 2.11
24 * only supports 4 and needs a workaround.
25 */
26 bool sclp_mask_compat_mode;
27
sclp_early_wait_irq(void)28 void sclp_early_wait_irq(void)
29 {
30 unsigned long psw_mask, addr;
31 psw_t psw_ext_save, psw_wait;
32 union ctlreg0 cr0, cr0_new;
33
34 __ctl_store(cr0.val, 0, 0);
35 cr0_new.val = cr0.val & ~CR0_IRQ_SUBCLASS_MASK;
36 cr0_new.lap = 0;
37 cr0_new.sssm = 1;
38 __ctl_load(cr0_new.val, 0, 0);
39
40 psw_ext_save = S390_lowcore.external_new_psw;
41 psw_mask = __extract_psw();
42 S390_lowcore.external_new_psw.mask = psw_mask;
43 psw_wait.mask = psw_mask | PSW_MASK_EXT | PSW_MASK_WAIT;
44 S390_lowcore.ext_int_code = 0;
45
46 do {
47 asm volatile(
48 " larl %[addr],0f\n"
49 " stg %[addr],%[psw_wait_addr]\n"
50 " stg %[addr],%[psw_ext_addr]\n"
51 " lpswe %[psw_wait]\n"
52 "0:\n"
53 : [addr] "=&d" (addr),
54 [psw_wait_addr] "=Q" (psw_wait.addr),
55 [psw_ext_addr] "=Q" (S390_lowcore.external_new_psw.addr)
56 : [psw_wait] "Q" (psw_wait)
57 : "cc", "memory");
58 } while (S390_lowcore.ext_int_code != EXT_IRQ_SERVICE_SIG);
59
60 S390_lowcore.external_new_psw = psw_ext_save;
61 __ctl_load(cr0.val, 0, 0);
62 }
63
sclp_early_cmd(sclp_cmdw_t cmd,void * sccb)64 int sclp_early_cmd(sclp_cmdw_t cmd, void *sccb)
65 {
66 unsigned long flags;
67 int rc;
68
69 flags = arch_local_irq_save();
70 rc = sclp_service_call(cmd, sccb);
71 if (rc)
72 goto out;
73 sclp_early_wait_irq();
74 out:
75 arch_local_irq_restore(flags);
76 return rc;
77 }
78
79 struct write_sccb {
80 struct sccb_header header;
81 struct msg_buf msg;
82 } __packed;
83
84 /* Output multi-line text using SCLP Message interface. */
sclp_early_print_lm(const char * str,unsigned int len)85 static void sclp_early_print_lm(const char *str, unsigned int len)
86 {
87 unsigned char *ptr, *end, ch;
88 unsigned int count, offset;
89 struct write_sccb *sccb;
90 struct msg_buf *msg;
91 struct mdb *mdb;
92 struct mto *mto;
93 struct go *go;
94
95 sccb = (struct write_sccb *) sclp_early_sccb;
96 end = (unsigned char *) sccb + EARLY_SCCB_SIZE - 1;
97 memset(sccb, 0, sizeof(*sccb));
98 ptr = (unsigned char *) &sccb->msg.mdb.mto;
99 offset = 0;
100 do {
101 for (count = sizeof(*mto); offset < len; count++) {
102 ch = str[offset++];
103 if ((ch == 0x0a) || (ptr + count > end))
104 break;
105 ptr[count] = _ascebc[ch];
106 }
107 mto = (struct mto *) ptr;
108 memset(mto, 0, sizeof(*mto));
109 mto->length = count;
110 mto->type = 4;
111 mto->line_type_flags = LNTPFLGS_ENDTEXT;
112 ptr += count;
113 } while ((offset < len) && (ptr + sizeof(*mto) <= end));
114 len = ptr - (unsigned char *) sccb;
115 sccb->header.length = len - offsetof(struct write_sccb, header);
116 msg = &sccb->msg;
117 msg->header.type = EVTYP_MSG;
118 msg->header.length = len - offsetof(struct write_sccb, msg.header);
119 mdb = &msg->mdb;
120 mdb->header.type = 1;
121 mdb->header.tag = 0xD4C4C240;
122 mdb->header.revision_code = 1;
123 mdb->header.length = len - offsetof(struct write_sccb, msg.mdb.header);
124 go = &mdb->go;
125 go->length = sizeof(*go);
126 go->type = 1;
127 sclp_early_cmd(SCLP_CMDW_WRITE_EVENT_DATA, sccb);
128 }
129
130 struct vt220_sccb {
131 struct sccb_header header;
132 struct {
133 struct evbuf_header header;
134 char data[];
135 } msg;
136 } __packed;
137
138 /* Output multi-line text using SCLP VT220 interface. */
sclp_early_print_vt220(const char * str,unsigned int len)139 static void sclp_early_print_vt220(const char *str, unsigned int len)
140 {
141 struct vt220_sccb *sccb;
142
143 sccb = (struct vt220_sccb *) sclp_early_sccb;
144 if (sizeof(*sccb) + len >= EARLY_SCCB_SIZE)
145 len = EARLY_SCCB_SIZE - sizeof(*sccb);
146 memset(sccb, 0, sizeof(*sccb));
147 memcpy(&sccb->msg.data, str, len);
148 sccb->header.length = sizeof(*sccb) + len;
149 sccb->msg.header.length = sizeof(sccb->msg) + len;
150 sccb->msg.header.type = EVTYP_VT220MSG;
151 sclp_early_cmd(SCLP_CMDW_WRITE_EVENT_DATA, sccb);
152 }
153
sclp_early_set_event_mask(struct init_sccb * sccb,sccb_mask_t receive_mask,sccb_mask_t send_mask)154 int sclp_early_set_event_mask(struct init_sccb *sccb,
155 sccb_mask_t receive_mask,
156 sccb_mask_t send_mask)
157 {
158 retry:
159 memset(sccb, 0, sizeof(*sccb));
160 sccb->header.length = sizeof(*sccb);
161 if (sclp_mask_compat_mode)
162 sccb->mask_length = SCLP_MASK_SIZE_COMPAT;
163 else
164 sccb->mask_length = sizeof(sccb_mask_t);
165 sccb_set_recv_mask(sccb, receive_mask);
166 sccb_set_send_mask(sccb, send_mask);
167 if (sclp_early_cmd(SCLP_CMDW_WRITE_EVENT_MASK, sccb))
168 return -EIO;
169 if ((sccb->header.response_code == 0x74f0) && !sclp_mask_compat_mode) {
170 sclp_mask_compat_mode = true;
171 goto retry;
172 }
173 if (sccb->header.response_code != 0x20)
174 return -EIO;
175 return 0;
176 }
177
sclp_early_con_check_linemode(struct init_sccb * sccb)178 unsigned int sclp_early_con_check_linemode(struct init_sccb *sccb)
179 {
180 if (!(sccb_get_sclp_send_mask(sccb) & EVTYP_OPCMD_MASK))
181 return 0;
182 if (!(sccb_get_sclp_recv_mask(sccb) & (EVTYP_MSG_MASK | EVTYP_PMSGCMD_MASK)))
183 return 0;
184 return 1;
185 }
186
sclp_early_con_check_vt220(struct init_sccb * sccb)187 unsigned int sclp_early_con_check_vt220(struct init_sccb *sccb)
188 {
189 if (sccb_get_sclp_send_mask(sccb) & EVTYP_VT220MSG_MASK)
190 return 1;
191 return 0;
192 }
193
sclp_early_setup(int disable,int * have_linemode,int * have_vt220)194 static int sclp_early_setup(int disable, int *have_linemode, int *have_vt220)
195 {
196 unsigned long receive_mask, send_mask;
197 struct init_sccb *sccb;
198 int rc;
199
200 BUILD_BUG_ON(sizeof(struct init_sccb) > PAGE_SIZE);
201
202 *have_linemode = *have_vt220 = 0;
203 sccb = (struct init_sccb *) sclp_early_sccb;
204 receive_mask = disable ? 0 : EVTYP_OPCMD_MASK;
205 send_mask = disable ? 0 : EVTYP_VT220MSG_MASK | EVTYP_MSG_MASK;
206 rc = sclp_early_set_event_mask(sccb, receive_mask, send_mask);
207 if (rc)
208 return rc;
209 *have_linemode = sclp_early_con_check_linemode(sccb);
210 *have_vt220 = !!(sccb_get_send_mask(sccb) & EVTYP_VT220MSG_MASK);
211 return rc;
212 }
213
sclp_early_set_buffer(void * sccb)214 void sclp_early_set_buffer(void *sccb)
215 {
216 sclp_early_sccb = sccb;
217 }
218
219 /*
220 * Output one or more lines of text on the SCLP console (VT220 and /
221 * or line-mode).
222 */
__sclp_early_printk(const char * str,unsigned int len)223 void __sclp_early_printk(const char *str, unsigned int len)
224 {
225 int have_linemode, have_vt220;
226
227 if (sclp_init_state != sclp_init_state_uninitialized)
228 return;
229 if (sclp_early_setup(0, &have_linemode, &have_vt220) != 0)
230 return;
231 if (have_linemode)
232 sclp_early_print_lm(str, len);
233 if (have_vt220)
234 sclp_early_print_vt220(str, len);
235 sclp_early_setup(1, &have_linemode, &have_vt220);
236 }
237
sclp_early_printk(const char * str)238 void sclp_early_printk(const char *str)
239 {
240 __sclp_early_printk(str, strlen(str));
241 }
242
243 /*
244 * Use sclp_emergency_printk() to print a string when the system is in a
245 * state where regular console drivers cannot be assumed to work anymore.
246 *
247 * Callers must make sure that no concurrent SCLP requests are outstanding
248 * and all other CPUs are stopped, or at least disabled for external
249 * interrupts.
250 */
sclp_emergency_printk(const char * str)251 void sclp_emergency_printk(const char *str)
252 {
253 int have_linemode, have_vt220;
254 unsigned int len;
255
256 len = strlen(str);
257 /*
258 * Don't care about return values; if requests fail, just ignore and
259 * continue to have a rather high chance that anything is printed.
260 */
261 sclp_early_setup(0, &have_linemode, &have_vt220);
262 sclp_early_print_lm(str, len);
263 sclp_early_print_vt220(str, len);
264 sclp_early_setup(1, &have_linemode, &have_vt220);
265 }
266
267 /*
268 * We can't pass sclp_info_sccb to sclp_early_cmd() here directly,
269 * because it might not fulfil the requiremets for a SCLP communication buffer:
270 * - lie below 2G in memory
271 * - be page-aligned
272 * Therefore, we use the buffer sclp_early_sccb (which fulfils all those
273 * requirements) temporarily for communication and copy a received response
274 * back into the buffer sclp_info_sccb upon successful completion.
275 */
sclp_early_read_info(void)276 int __init sclp_early_read_info(void)
277 {
278 int i;
279 int length = test_facility(140) ? EXT_SCCB_READ_SCP : PAGE_SIZE;
280 struct read_info_sccb *sccb = (struct read_info_sccb *)sclp_early_sccb;
281 sclp_cmdw_t commands[] = {SCLP_CMDW_READ_SCP_INFO_FORCED,
282 SCLP_CMDW_READ_SCP_INFO};
283
284 for (i = 0; i < ARRAY_SIZE(commands); i++) {
285 memset(sccb, 0, length);
286 sccb->header.length = length;
287 sccb->header.function_code = 0x80;
288 sccb->header.control_mask[2] = 0x80;
289 if (sclp_early_cmd(commands[i], sccb))
290 break;
291 if (sccb->header.response_code == 0x10) {
292 memcpy(&sclp_info_sccb, sccb, length);
293 sclp_info_sccb_valid = 1;
294 return 0;
295 }
296 if (sccb->header.response_code != 0x1f0)
297 break;
298 }
299 return -EIO;
300 }
301
sclp_early_get_info(void)302 struct read_info_sccb * __init sclp_early_get_info(void)
303 {
304 if (!sclp_info_sccb_valid)
305 return NULL;
306
307 return &sclp_info_sccb;
308 }
309
sclp_early_get_memsize(unsigned long * mem)310 int __init sclp_early_get_memsize(unsigned long *mem)
311 {
312 unsigned long rnmax;
313 unsigned long rnsize;
314 struct read_info_sccb *sccb = &sclp_info_sccb;
315
316 if (!sclp_info_sccb_valid)
317 return -EIO;
318
319 rnmax = sccb->rnmax ? sccb->rnmax : sccb->rnmax2;
320 rnsize = sccb->rnsize ? sccb->rnsize : sccb->rnsize2;
321 rnsize <<= 20;
322 *mem = rnsize * rnmax;
323 return 0;
324 }
325
sclp_early_get_hsa_size(unsigned long * hsa_size)326 int __init sclp_early_get_hsa_size(unsigned long *hsa_size)
327 {
328 if (!sclp_info_sccb_valid)
329 return -EIO;
330
331 *hsa_size = 0;
332 if (sclp_info_sccb.hsa_size)
333 *hsa_size = (sclp_info_sccb.hsa_size - 1) * PAGE_SIZE;
334 return 0;
335 }
336
337 #define SCLP_STORAGE_INFO_FACILITY 0x0000400000000000UL
338
add_physmem_online_range(u64 start,u64 end)339 void __weak __init add_physmem_online_range(u64 start, u64 end) {}
sclp_early_read_storage_info(void)340 int __init sclp_early_read_storage_info(void)
341 {
342 struct read_storage_sccb *sccb = (struct read_storage_sccb *)sclp_early_sccb;
343 int rc, id, max_id = 0;
344 unsigned long rn, rzm;
345 sclp_cmdw_t command;
346 u16 sn;
347
348 if (!sclp_info_sccb_valid)
349 return -EIO;
350
351 if (!(sclp_info_sccb.facilities & SCLP_STORAGE_INFO_FACILITY))
352 return -EOPNOTSUPP;
353
354 rzm = sclp_info_sccb.rnsize ?: sclp_info_sccb.rnsize2;
355 rzm <<= 20;
356
357 for (id = 0; id <= max_id; id++) {
358 memset(sclp_early_sccb, 0, EARLY_SCCB_SIZE);
359 sccb->header.length = EARLY_SCCB_SIZE;
360 command = SCLP_CMDW_READ_STORAGE_INFO | (id << 8);
361 rc = sclp_early_cmd(command, sccb);
362 if (rc)
363 goto fail;
364
365 max_id = sccb->max_id;
366 switch (sccb->header.response_code) {
367 case 0x0010:
368 for (sn = 0; sn < sccb->assigned; sn++) {
369 if (!sccb->entries[sn])
370 continue;
371 rn = sccb->entries[sn] >> 16;
372 add_physmem_online_range((rn - 1) * rzm, rn * rzm);
373 }
374 break;
375 case 0x0310:
376 case 0x0410:
377 break;
378 default:
379 goto fail;
380 }
381 }
382
383 return 0;
384 fail:
385 physmem_info.range_count = 0;
386 return -EIO;
387 }
388