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 "sclp.h"
15 #include "sclp_rw.h"
16 
17 static struct read_info_sccb __bootdata(sclp_info_sccb);
18 static int __bootdata(sclp_info_sccb_valid);
19 char sclp_early_sccb[PAGE_SIZE] __aligned(PAGE_SIZE) __section(.data);
20 int sclp_init_state __section(.data) = sclp_init_state_uninitialized;
21 /*
22  * Used to keep track of the size of the event masks. Qemu until version 2.11
23  * only supports 4 and needs a workaround.
24  */
25 bool sclp_mask_compat_mode __section(.data);
26 
27 void sclp_early_wait_irq(void)
28 {
29 	unsigned long psw_mask, addr;
30 	psw_t psw_ext_save, psw_wait;
31 	union ctlreg0 cr0, cr0_new;
32 
33 	__ctl_store(cr0.val, 0, 0);
34 	cr0_new.val = cr0.val & ~CR0_IRQ_SUBCLASS_MASK;
35 	cr0_new.lap = 0;
36 	cr0_new.sssm = 1;
37 	__ctl_load(cr0_new.val, 0, 0);
38 
39 	psw_ext_save = S390_lowcore.external_new_psw;
40 	psw_mask = __extract_psw();
41 	S390_lowcore.external_new_psw.mask = psw_mask;
42 	psw_wait.mask = psw_mask | PSW_MASK_EXT | PSW_MASK_WAIT;
43 	S390_lowcore.ext_int_code = 0;
44 
45 	do {
46 		asm volatile(
47 			"	larl	%[addr],0f\n"
48 			"	stg	%[addr],%[psw_wait_addr]\n"
49 			"	stg	%[addr],%[psw_ext_addr]\n"
50 			"	lpswe	%[psw_wait]\n"
51 			"0:\n"
52 			: [addr] "=&d" (addr),
53 			  [psw_wait_addr] "=Q" (psw_wait.addr),
54 			  [psw_ext_addr] "=Q" (S390_lowcore.external_new_psw.addr)
55 			: [psw_wait] "Q" (psw_wait)
56 			: "cc", "memory");
57 	} while (S390_lowcore.ext_int_code != EXT_IRQ_SERVICE_SIG);
58 
59 	S390_lowcore.external_new_psw = psw_ext_save;
60 	__ctl_load(cr0.val, 0, 0);
61 }
62 
63 int sclp_early_cmd(sclp_cmdw_t cmd, void *sccb)
64 {
65 	unsigned long flags;
66 	int rc;
67 
68 	raw_local_irq_save(flags);
69 	rc = sclp_service_call(cmd, sccb);
70 	if (rc)
71 		goto out;
72 	sclp_early_wait_irq();
73 out:
74 	raw_local_irq_restore(flags);
75 	return rc;
76 }
77 
78 struct write_sccb {
79 	struct sccb_header header;
80 	struct msg_buf msg;
81 } __packed;
82 
83 /* Output multi-line text using SCLP Message interface. */
84 static void sclp_early_print_lm(const char *str, unsigned int len)
85 {
86 	unsigned char *ptr, *end, ch;
87 	unsigned int count, offset;
88 	struct write_sccb *sccb;
89 	struct msg_buf *msg;
90 	struct mdb *mdb;
91 	struct mto *mto;
92 	struct go *go;
93 
94 	sccb = (struct write_sccb *) &sclp_early_sccb;
95 	end = (unsigned char *) sccb + sizeof(sclp_early_sccb) - 1;
96 	memset(sccb, 0, sizeof(*sccb));
97 	ptr = (unsigned char *) &sccb->msg.mdb.mto;
98 	offset = 0;
99 	do {
100 		for (count = sizeof(*mto); offset < len; count++) {
101 			ch = str[offset++];
102 			if ((ch == 0x0a) || (ptr + count > end))
103 				break;
104 			ptr[count] = _ascebc[ch];
105 		}
106 		mto = (struct mto *) ptr;
107 		memset(mto, 0, sizeof(*mto));
108 		mto->length = count;
109 		mto->type = 4;
110 		mto->line_type_flags = LNTPFLGS_ENDTEXT;
111 		ptr += count;
112 	} while ((offset < len) && (ptr + sizeof(*mto) <= end));
113 	len = ptr - (unsigned char *) sccb;
114 	sccb->header.length = len - offsetof(struct write_sccb, header);
115 	msg = &sccb->msg;
116 	msg->header.type = EVTYP_MSG;
117 	msg->header.length = len - offsetof(struct write_sccb, msg.header);
118 	mdb = &msg->mdb;
119 	mdb->header.type = 1;
120 	mdb->header.tag = 0xD4C4C240;
121 	mdb->header.revision_code = 1;
122 	mdb->header.length = len - offsetof(struct write_sccb, msg.mdb.header);
123 	go = &mdb->go;
124 	go->length = sizeof(*go);
125 	go->type = 1;
126 	sclp_early_cmd(SCLP_CMDW_WRITE_EVENT_DATA, sccb);
127 }
128 
129 struct vt220_sccb {
130 	struct sccb_header header;
131 	struct {
132 		struct evbuf_header header;
133 		char data[];
134 	} msg;
135 } __packed;
136 
137 /* Output multi-line text using SCLP VT220 interface. */
138 static void sclp_early_print_vt220(const char *str, unsigned int len)
139 {
140 	struct vt220_sccb *sccb;
141 
142 	sccb = (struct vt220_sccb *) &sclp_early_sccb;
143 	if (sizeof(*sccb) + len >= sizeof(sclp_early_sccb))
144 		len = sizeof(sclp_early_sccb) - sizeof(*sccb);
145 	memset(sccb, 0, sizeof(*sccb));
146 	memcpy(&sccb->msg.data, str, len);
147 	sccb->header.length = sizeof(*sccb) + len;
148 	sccb->msg.header.length = sizeof(sccb->msg) + len;
149 	sccb->msg.header.type = EVTYP_VT220MSG;
150 	sclp_early_cmd(SCLP_CMDW_WRITE_EVENT_DATA, sccb);
151 }
152 
153 int sclp_early_set_event_mask(struct init_sccb *sccb,
154 			      sccb_mask_t receive_mask,
155 			      sccb_mask_t send_mask)
156 {
157 retry:
158 	memset(sccb, 0, sizeof(*sccb));
159 	sccb->header.length = sizeof(*sccb);
160 	if (sclp_mask_compat_mode)
161 		sccb->mask_length = SCLP_MASK_SIZE_COMPAT;
162 	else
163 		sccb->mask_length = sizeof(sccb_mask_t);
164 	sccb_set_recv_mask(sccb, receive_mask);
165 	sccb_set_send_mask(sccb, send_mask);
166 	if (sclp_early_cmd(SCLP_CMDW_WRITE_EVENT_MASK, sccb))
167 		return -EIO;
168 	if ((sccb->header.response_code == 0x74f0) && !sclp_mask_compat_mode) {
169 		sclp_mask_compat_mode = true;
170 		goto retry;
171 	}
172 	if (sccb->header.response_code != 0x20)
173 		return -EIO;
174 	return 0;
175 }
176 
177 unsigned int sclp_early_con_check_linemode(struct init_sccb *sccb)
178 {
179 	if (!(sccb_get_sclp_send_mask(sccb) & EVTYP_OPCMD_MASK))
180 		return 0;
181 	if (!(sccb_get_sclp_recv_mask(sccb) & (EVTYP_MSG_MASK | EVTYP_PMSGCMD_MASK)))
182 		return 0;
183 	return 1;
184 }
185 
186 unsigned int sclp_early_con_check_vt220(struct init_sccb *sccb)
187 {
188 	if (sccb_get_sclp_send_mask(sccb) & EVTYP_VT220MSG_MASK)
189 		return 1;
190 	return 0;
191 }
192 
193 static int sclp_early_setup(int disable, int *have_linemode, int *have_vt220)
194 {
195 	unsigned long receive_mask, send_mask;
196 	struct init_sccb *sccb;
197 	int rc;
198 
199 	BUILD_BUG_ON(sizeof(struct init_sccb) > PAGE_SIZE);
200 
201 	*have_linemode = *have_vt220 = 0;
202 	sccb = (struct init_sccb *) &sclp_early_sccb;
203 	receive_mask = disable ? 0 : EVTYP_OPCMD_MASK;
204 	send_mask = disable ? 0 : EVTYP_VT220MSG_MASK | EVTYP_MSG_MASK;
205 	rc = sclp_early_set_event_mask(sccb, receive_mask, send_mask);
206 	if (rc)
207 		return rc;
208 	*have_linemode = sclp_early_con_check_linemode(sccb);
209 	*have_vt220 = !!(sccb_get_send_mask(sccb) & EVTYP_VT220MSG_MASK);
210 	return rc;
211 }
212 
213 /*
214  * Output one or more lines of text on the SCLP console (VT220 and /
215  * or line-mode).
216  */
217 void __sclp_early_printk(const char *str, unsigned int len, unsigned int force)
218 {
219 	int have_linemode, have_vt220;
220 
221 	if (!force && sclp_init_state != sclp_init_state_uninitialized)
222 		return;
223 	if (sclp_early_setup(0, &have_linemode, &have_vt220) != 0)
224 		return;
225 	if (have_linemode)
226 		sclp_early_print_lm(str, len);
227 	if (have_vt220)
228 		sclp_early_print_vt220(str, len);
229 	sclp_early_setup(1, &have_linemode, &have_vt220);
230 }
231 
232 void sclp_early_printk(const char *str)
233 {
234 	__sclp_early_printk(str, strlen(str), 0);
235 }
236 
237 void sclp_early_printk_force(const char *str)
238 {
239 	__sclp_early_printk(str, strlen(str), 1);
240 }
241 
242 int __init sclp_early_read_info(void)
243 {
244 	int i;
245 	struct read_info_sccb *sccb = &sclp_info_sccb;
246 	sclp_cmdw_t commands[] = {SCLP_CMDW_READ_SCP_INFO_FORCED,
247 				  SCLP_CMDW_READ_SCP_INFO};
248 
249 	for (i = 0; i < ARRAY_SIZE(commands); i++) {
250 		memset(sccb, 0, sizeof(*sccb));
251 		sccb->header.length = sizeof(*sccb);
252 		sccb->header.function_code = 0x80;
253 		sccb->header.control_mask[2] = 0x80;
254 		if (sclp_early_cmd(commands[i], sccb))
255 			break;
256 		if (sccb->header.response_code == 0x10) {
257 			sclp_info_sccb_valid = 1;
258 			return 0;
259 		}
260 		if (sccb->header.response_code != 0x1f0)
261 			break;
262 	}
263 	return -EIO;
264 }
265 
266 int __init sclp_early_get_info(struct read_info_sccb *info)
267 {
268 	if (!sclp_info_sccb_valid)
269 		return -EIO;
270 
271 	*info = sclp_info_sccb;
272 	return 0;
273 }
274 
275 int __init sclp_early_get_memsize(unsigned long *mem)
276 {
277 	unsigned long rnmax;
278 	unsigned long rnsize;
279 	struct read_info_sccb *sccb = &sclp_info_sccb;
280 
281 	if (!sclp_info_sccb_valid)
282 		return -EIO;
283 
284 	rnmax = sccb->rnmax ? sccb->rnmax : sccb->rnmax2;
285 	rnsize = sccb->rnsize ? sccb->rnsize : sccb->rnsize2;
286 	rnsize <<= 20;
287 	*mem = rnsize * rnmax;
288 	return 0;
289 }
290 
291 int __init sclp_early_get_hsa_size(unsigned long *hsa_size)
292 {
293 	if (!sclp_info_sccb_valid)
294 		return -EIO;
295 
296 	*hsa_size = 0;
297 	if (sclp_info_sccb.hsa_size)
298 		*hsa_size = (sclp_info_sccb.hsa_size - 1) * PAGE_SIZE;
299 	return 0;
300 }
301 
302 #define SCLP_STORAGE_INFO_FACILITY     0x0000400000000000UL
303 
304 void __weak __init add_mem_detect_block(u64 start, u64 end) {}
305 int __init sclp_early_read_storage_info(void)
306 {
307 	struct read_storage_sccb *sccb = (struct read_storage_sccb *)&sclp_early_sccb;
308 	int rc, id, max_id = 0;
309 	unsigned long rn, rzm;
310 	sclp_cmdw_t command;
311 	u16 sn;
312 
313 	if (!sclp_info_sccb_valid)
314 		return -EIO;
315 
316 	if (!(sclp_info_sccb.facilities & SCLP_STORAGE_INFO_FACILITY))
317 		return -EOPNOTSUPP;
318 
319 	rzm = sclp_info_sccb.rnsize ?: sclp_info_sccb.rnsize2;
320 	rzm <<= 20;
321 
322 	for (id = 0; id <= max_id; id++) {
323 		memset(sclp_early_sccb, 0, sizeof(sclp_early_sccb));
324 		sccb->header.length = sizeof(sclp_early_sccb);
325 		command = SCLP_CMDW_READ_STORAGE_INFO | (id << 8);
326 		rc = sclp_early_cmd(command, sccb);
327 		if (rc)
328 			goto fail;
329 
330 		max_id = sccb->max_id;
331 		switch (sccb->header.response_code) {
332 		case 0x0010:
333 			for (sn = 0; sn < sccb->assigned; sn++) {
334 				if (!sccb->entries[sn])
335 					continue;
336 				rn = sccb->entries[sn] >> 16;
337 				add_mem_detect_block((rn - 1) * rzm, rn * rzm);
338 			}
339 			break;
340 		case 0x0310:
341 		case 0x0410:
342 			break;
343 		default:
344 			goto fail;
345 		}
346 	}
347 
348 	return 0;
349 fail:
350 	mem_detect.count = 0;
351 	return -EIO;
352 }
353