xref: /kvm-unit-tests/lib/s390x/sclp-console.c (revision 97d4fb3041be25375dcfe2536c6c047c3fd9820a)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * SCLP ASCII access driver
4  *
5  * Copyright (c) 2013 Alexander Graf <agraf@suse.de>
6  */
7 
8 #include <libcflat.h>
9 #include <string.h>
10 #include <asm/page.h>
11 #include <asm/arch_def.h>
12 #include <asm/io.h>
13 #include <asm/spinlock.h>
14 #include "hardware.h"
15 #include "sclp.h"
16 
17 /*
18  * ASCII (IBM PC 437) -> EBCDIC 037
19  */
20 static uint8_t _ascebc[256] = {
21  /*00 NUL   SOH   STX   ETX   EOT   ENQ   ACK   BEL */
22      0x00, 0x01, 0x02, 0x03, 0x37, 0x2D, 0x2E, 0x2F,
23  /*08  BS    HT    LF    VT    FF    CR    SO    SI */
24  /*              ->NL                               */
25      0x16, 0x05, 0x15, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F,
26  /*10 DLE   DC1   DC2   DC3   DC4   NAK   SYN   ETB */
27      0x10, 0x11, 0x12, 0x13, 0x3C, 0x3D, 0x32, 0x26,
28  /*18 CAN    EM   SUB   ESC    FS    GS    RS    US */
29  /*                               ->IGS ->IRS ->IUS */
30      0x18, 0x19, 0x3F, 0x27, 0x22, 0x1D, 0x1E, 0x1F,
31  /*20  SP     !     "     #     $     %     &     ' */
32      0x40, 0x5A, 0x7F, 0x7B, 0x5B, 0x6C, 0x50, 0x7D,
33  /*28   (     )     *     +     ,     -    .      / */
34      0x4D, 0x5D, 0x5C, 0x4E, 0x6B, 0x60, 0x4B, 0x61,
35  /*30   0     1     2     3     4     5     6     7 */
36      0xF0, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7,
37  /*38   8     9     :     ;     <     =     >     ? */
38      0xF8, 0xF9, 0x7A, 0x5E, 0x4C, 0x7E, 0x6E, 0x6F,
39  /*40   @     A     B     C     D     E     F     G */
40      0x7C, 0xC1, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7,
41  /*48   H     I     J     K     L     M     N     O */
42      0xC8, 0xC9, 0xD1, 0xD2, 0xD3, 0xD4, 0xD5, 0xD6,
43  /*50   P     Q     R     S     T     U     V     W */
44      0xD7, 0xD8, 0xD9, 0xE2, 0xE3, 0xE4, 0xE5, 0xE6,
45  /*58   X     Y     Z     [     \     ]     ^     _ */
46      0xE7, 0xE8, 0xE9, 0xBA, 0xE0, 0xBB, 0xB0, 0x6D,
47  /*60   `     a     b     c     d     e     f     g */
48      0x79, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
49  /*68   h     i     j     k     l     m     n     o */
50      0x88, 0x89, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96,
51  /*70   p     q     r     s     t     u     v     w */
52      0x97, 0x98, 0x99, 0xA2, 0xA3, 0xA4, 0xA5, 0xA6,
53  /*78   x     y     z     {     |     }     ~    DL */
54      0xA7, 0xA8, 0xA9, 0xC0, 0x4F, 0xD0, 0xA1, 0x07,
55  /*80*/
56      0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
57  /*88*/
58      0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
59  /*90*/
60      0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
61  /*98*/
62      0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
63  /*A0*/
64      0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
65  /*A8*/
66      0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
67  /*B0*/
68      0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
69  /*B8*/
70      0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
71  /*C0*/
72      0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
73  /*C8*/
74      0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
75  /*D0*/
76      0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
77  /*D8*/
78      0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
79  /*E0        sz	*/
80      0x3F, 0x59, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
81  /*E8*/
82      0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
83  /*F0*/
84      0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F, 0x3F,
85  /*F8*/
86      0x90, 0x3F, 0x3F, 0x3F, 0x3F, 0xEA, 0x3F, 0xFF
87 };
88 
89 static bool lpar_ascii_compat;
90 
91 static char lm_buff[120];
92 static unsigned char lm_buff_off;
93 static struct spinlock lm_buff_lock;
94 
95 static char read_buf[4096];
96 static int read_index = sizeof(read_buf) - 1;
97 static int read_buf_length = 0;
98 
99 static void sclp_print_ascii(const char *str)
100 {
101 	int len = strlen(str);
102 	WriteEventData *sccb = (void *)_sccb;
103 	char *str_dest = (char *)&sccb->msg;
104 	int src_ind, dst_ind;
105 
106 	sclp_mark_busy();
107 	memset(sccb, 0, sizeof(*sccb));
108 
109 	for (src_ind = 0, dst_ind = 0;
110 	     src_ind < len && dst_ind < (PAGE_SIZE / 2);
111 	     src_ind++, dst_ind++) {
112 		str_dest[dst_ind] = str[src_ind];
113 		/* Add a \r to the \n for HMC ASCII console */
114 		if (str[src_ind] == '\n' && lpar_ascii_compat) {
115 			dst_ind++;
116 			str_dest[dst_ind] = '\r';
117 		}
118 	}
119 
120 	/* Len might have changed because of the compat behavior */
121 	len = dst_ind;
122 	sccb->h.length = offsetof(WriteEventData, msg) + len;
123 	sccb->h.function_code = SCLP_FC_NORMAL_WRITE;
124 	sccb->ebh.length = sizeof(EventBufferHeader) + len;
125 	sccb->ebh.type = SCLP_EVENT_ASCII_CONSOLE_DATA;
126 
127 	sclp_service_call(SCLP_CMD_WRITE_EVENT_DATA, sccb);
128 }
129 
130 static void lm_print(const char *buff, int len)
131 {
132 	unsigned char *ptr, *end, ch;
133 	unsigned int count, offset;
134 	struct WriteEventData *sccb;
135 	struct mdb *mdb;
136 	struct mto *mto;
137 	struct go *go;
138 
139 	sclp_mark_busy();
140 	sccb = (struct WriteEventData *) _sccb;
141 	end = (unsigned char *) sccb + 4096 - 1;
142 	memset(sccb, 0, sizeof(*sccb));
143 	ptr = (unsigned char *) &sccb->msg.mdb.mto;
144 	offset = 0;
145 	do {
146 		for (count = sizeof(*mto); offset < len; count++) {
147 			ch = buff[offset++];
148 			if (ch == 0x0a || ptr + count > end)
149 				break;
150 			ptr[count] = _ascebc[ch];
151 		}
152 		mto = (struct mto *) ptr;
153 		mto->length = count;
154 		mto->type = 4;
155 		mto->line_type_flags = LNTPFLGS_ENDTEXT;
156 		ptr += count;
157 	} while (offset < len && ptr + sizeof(*mto) <= end);
158 	len = ptr - (unsigned char *) sccb;
159 	sccb->h.length = len - offsetof(struct WriteEventData, h);
160 	sccb->h.function_code = SCLP_FC_NORMAL_WRITE;
161 	sccb->ebh.type = EVTYP_MSG;
162 	sccb->ebh.length = len - offsetof(struct WriteEventData, ebh);
163 	mdb = &sccb->msg.mdb;
164 	mdb->header.type = 1;
165 	mdb->header.tag = 0xD4C4C240;
166 	mdb->header.revision_code = 1;
167 	mdb->header.length = len - offsetof(struct WriteEventData, msg.mdb.header);
168 	go = &mdb->go;
169 	go->length = sizeof(*go);
170 	go->type = 1;
171 	sclp_service_call(SCLP_CMD_WRITE_EVENT_DATA, sccb);
172 }
173 
174 
175 /*
176  * In contrast to the ascii console, linemode produces a new
177  * line with every write of data. The report() function uses
178  * several printf() calls to generate a line of data which
179  * would all end up on different lines.
180  *
181  * Hence we buffer here until we encounter a \n or the buffer
182  * is full. That means that linemode output can look a bit
183  * different from ascii and that it takes a bit longer for
184  * lines to appear.
185  */
186 static void sclp_print_lm(const char *str)
187 {
188 	int i;
189 	const int len = strlen(str);
190 
191 	spin_lock(&lm_buff_lock);
192 
193 	for (i = 0; i < len; i++) {
194 		lm_buff[lm_buff_off++] = str[i];
195 
196 		/* Buffer full or newline? */
197 		if (str[i] == '\n' || lm_buff_off == (ARRAY_SIZE(lm_buff) - 1)) {
198 			lm_print(lm_buff, lm_buff_off);
199 			lm_buff_off = 0;
200 		}
201 	}
202 	spin_unlock(&lm_buff_lock);
203 }
204 
205 /*
206  * SCLP needs to be initialized by setting a send and receive mask,
207  * indicating which messages the control program (we) want(s) to
208  * send/receive.
209  */
210 static void sclp_write_event_mask(int receive_mask, int send_mask)
211 {
212 	WriteEventMask *sccb = (void *)_sccb;
213 
214 	sclp_mark_busy();
215 	memset(_sccb, 0, sizeof(*sccb));
216 	sccb->h.length = sizeof(WriteEventMask);
217 	sccb->h.function_code = SCLP_FC_NORMAL_WRITE;
218 	sccb->mask_length = sizeof(sccb_mask_t);
219 
220 	sccb->cp_receive_mask = receive_mask;
221 	sccb->cp_send_mask = send_mask;
222 
223 	sclp_service_call(SCLP_CMD_WRITE_EVENT_MASK, sccb);
224 	assert(sccb->h.response_code == SCLP_RC_NORMAL_COMPLETION);
225 }
226 
227 static void sclp_console_enable_read(void)
228 {
229 	sclp_write_event_mask(SCLP_EVENT_MASK_MSG_ASCII, SCLP_EVENT_MASK_MSG_ASCII | SCLP_EVENT_MASK_MSG);
230 }
231 
232 static void sclp_console_disable_read(void)
233 {
234 	sclp_write_event_mask(0, SCLP_EVENT_MASK_MSG_ASCII | SCLP_EVENT_MASK_MSG);
235 }
236 
237 void sclp_console_setup(void)
238 {
239 	lpar_ascii_compat = detect_host() == HOST_IS_LPAR;
240 
241 	/* We send ASCII and line mode. */
242 	sclp_write_event_mask(0, SCLP_EVENT_MASK_MSG_ASCII | SCLP_EVENT_MASK_MSG);
243 	/* Hard terminal reset to clear screen for HMC ASCII console */
244 	if (lpar_ascii_compat)
245 		sclp_print_ascii("\ec");
246 }
247 
248 void sclp_print(const char *str)
249 {
250 	/*
251 	 * z/VM advertises a vt220 console which is not functional:
252 	 * (response code 05F0, "not active because of the state of
253 	 * the machine"). Hence testing the masks would only work if
254 	 * we also use stsi data to distinguish z/VM.
255 	 *
256 	 * Let's rather print on all available consoles.
257 	 */
258 	if (strlen(str) > (PAGE_SIZE / 2)) {
259 		sclp_print_ascii("Warning: Printing is limited to 2KB of data.");
260 		sclp_print_lm("Warning: Printing is limited to 2KB of data.");
261 		return;
262 	}
263 	sclp_print_ascii(str);
264 	sclp_print_lm(str);
265 }
266 
267 static int console_refill_read_buffer(void)
268 {
269 	const int max_event_buffer_len = SCCB_SIZE - offsetof(ReadEventDataAsciiConsole, ebh);
270 	ReadEventDataAsciiConsole *sccb = (void *)_sccb;
271 	const int event_buffer_ascii_recv_header_len = sizeof(sccb->ebh) + sizeof(sccb->type);
272 	int ret = -1;
273 
274 	sclp_console_enable_read();
275 
276 	sclp_mark_busy();
277 	memset(sccb, 0, SCCB_SIZE);
278 	sccb->h.length = PAGE_SIZE;
279 	sccb->h.function_code = SCLP_UNCONDITIONAL_READ;
280 	sccb->h.control_mask[2] = SCLP_CM2_VARIABLE_LENGTH_RESPONSE;
281 
282 	sclp_service_call(SCLP_CMD_READ_EVENT_DATA, sccb);
283 
284 	if (sccb->h.response_code == SCLP_RC_NO_EVENT_BUFFERS_STORED ||
285 	    sccb->ebh.type != SCLP_EVENT_ASCII_CONSOLE_DATA ||
286 	    sccb->type != SCLP_EVENT_ASCII_TYPE_DATA_STREAM_FOLLOWS) {
287 		ret = -1;
288 		goto out;
289 	}
290 
291 	assert(sccb->ebh.length <= max_event_buffer_len);
292 	assert(sccb->ebh.length > event_buffer_ascii_recv_header_len);
293 
294 	read_buf_length = sccb->ebh.length - event_buffer_ascii_recv_header_len;
295 
296 	assert(read_buf_length <= sizeof(read_buf));
297 	memcpy(read_buf, sccb->data, read_buf_length);
298 
299 	read_index = 0;
300 	ret = 0;
301 
302 out:
303 	sclp_console_disable_read();
304 
305 	return ret;
306 }
307 
308 int __getchar(void)
309 {
310 	int ret;
311 
312 	if (read_index >= read_buf_length) {
313 		ret = console_refill_read_buffer();
314 		if (ret < 0)
315 			return ret;
316 	}
317 
318 	return read_buf[read_index++];
319 }
320