1 /*
2 * SCLP ASCII access driver
3 *
4 * Copyright (c) 2013 Alexander Graf <agraf@suse.de>
5 *
6 * This work is licensed under the terms of the GNU GPL, version 2 or (at
7 * your option) any later version. See the COPYING file in the top-level
8 * directory.
9 */
10
11 #include <string.h>
12 #include "s390-ccw.h"
13 #include "sclp.h"
14
15 long write(int fd, const void *str, size_t len);
16
17 static char _sccb[PAGE_SIZE] __attribute__((__aligned__(4096)));
18
19 const unsigned char ebc2asc[256] =
20 /* 0123456789abcdef0123456789abcdef */
21 "................................" /* 1F */
22 "................................" /* 3F */
23 " ...........<(+|&.........!$*);." /* 5F first.chr.here.is.real.space */
24 "-/.........,%_>?.........`:#@'=\""/* 7F */
25 ".abcdefghi.......jklmnopqr......" /* 9F */
26 "..stuvwxyz......................" /* BF */
27 ".ABCDEFGHI.......JKLMNOPQR......" /* DF */
28 "..STUVWXYZ......0123456789......";/* FF */
29
30 /* Perform service call. Return 0 on success, non-zero otherwise. */
sclp_service_call(unsigned int command,void * sccb)31 static int sclp_service_call(unsigned int command, void *sccb)
32 {
33 int cc;
34
35 asm volatile(
36 " .insn rre,0xb2200000,%1,%2\n" /* servc %1,%2 */
37 " ipm %0\n"
38 " srl %0,28"
39 : "=&d" (cc) : "d" (command), "a" (__pa(sccb))
40 : "cc", "memory");
41 consume_sclp_int();
42 if (cc == 3)
43 return -EIO;
44 if (cc == 2)
45 return -EBUSY;
46 return 0;
47 }
48
sclp_set_write_mask(uint32_t receive_mask,uint32_t send_mask)49 void sclp_set_write_mask(uint32_t receive_mask, uint32_t send_mask)
50 {
51 WriteEventMask *sccb = (void *)_sccb;
52
53 sccb->h.length = sizeof(WriteEventMask);
54 sccb->mask_length = sizeof(unsigned int);
55 sccb->cp_receive_mask = receive_mask;
56 sccb->cp_send_mask = send_mask;
57
58 sclp_service_call(SCLP_CMD_WRITE_EVENT_MASK, sccb);
59 }
60
sclp_setup(void)61 void sclp_setup(void)
62 {
63 sclp_set_write_mask(0, SCLP_EVENT_MASK_MSG_ASCII);
64 }
65
write(int fd,const void * str,size_t len)66 long write(int fd, const void *str, size_t len)
67 {
68 WriteEventData *sccb = (void *)_sccb;
69 const char *p = str;
70 size_t data_len = 0;
71 size_t i;
72
73 if (fd != 1 && fd != 2) {
74 return -EIO;
75 }
76
77 for (i = 0; i < len; i++) {
78 if ((data_len + 1) >= SCCB_DATA_LEN) {
79 /* We would overflow the sccb buffer, abort early */
80 len = i;
81 break;
82 }
83
84 if (*p == '\n') {
85 /* Terminal emulators might need \r\n, so generate it */
86 sccb->data[data_len++] = '\r';
87 }
88
89 sccb->data[data_len++] = *p;
90 p++;
91 }
92
93 sccb->h.length = sizeof(WriteEventData) + data_len;
94 sccb->h.function_code = SCLP_FC_NORMAL_WRITE;
95 sccb->ebh.length = sizeof(EventBufferHeader) + data_len;
96 sccb->ebh.type = SCLP_EVENT_ASCII_CONSOLE_DATA;
97 sccb->ebh.flags = 0;
98
99 sclp_service_call(SCLP_CMD_WRITE_EVENT_DATA, sccb);
100
101 return len;
102 }
103
sclp_get_loadparm_ascii(char * loadparm)104 void sclp_get_loadparm_ascii(char *loadparm)
105 {
106
107 ReadInfo *sccb = (void *)_sccb;
108
109 memset((char *)_sccb, 0, sizeof(ReadInfo));
110 sccb->h.length = SCCB_SIZE;
111 if (!sclp_service_call(SCLP_CMDW_READ_SCP_INFO, sccb)) {
112 ebcdic_to_ascii((char *) sccb->loadparm, loadparm, LOADPARM_LEN);
113 }
114 }
115
sclp_read(char * str,size_t count)116 int sclp_read(char *str, size_t count)
117 {
118 ReadEventData *sccb = (void *)_sccb;
119 char *buf = (char *)(&sccb->ebh) + 7;
120
121 /* If count exceeds max buffer size, then restrict it to the max size */
122 if (count > SCCB_SIZE - 8) {
123 count = SCCB_SIZE - 8;
124 }
125
126 sccb->h.length = SCCB_SIZE;
127 sccb->h.function_code = SCLP_UNCONDITIONAL_READ;
128
129 sclp_service_call(SCLP_CMD_READ_EVENT_DATA, sccb);
130 memcpy(str, buf, count);
131
132 return sccb->ebh.length - 7;
133 }
134