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/mem_detect.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 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 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. */ 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. */ 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 } 153 154 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 } 177 178 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 } 186 187 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 } 193 194 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 } 213 214 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 */ 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 } 237 238 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 */ 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 */ 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 } 301 302 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 } 309 310 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 } 325 326 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 338 339 void __weak __init add_mem_detect_block(u64 start, u64 end) {} 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_mem_detect_block((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 mem_detect.count = 0; 386 return -EIO; 387 } 388