pc-bios/s390-ccw/sclp.c

   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 "libc.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. */
  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
  49 static void sclp_set_write_mask(void)
  50 {
  51     WriteEventMask *sccb = (void *)_sccb;
  52
  53     sccb->h.length = sizeof(WriteEventMask);
  54     sccb->mask_length = sizeof(unsigned int);
  55     sccb->receive_mask = SCLP_EVENT_MASK_MSG_ASCII;
  56     sccb->cp_receive_mask = SCLP_EVENT_MASK_MSG_ASCII;
  57     sccb->send_mask = SCLP_EVENT_MASK_MSG_ASCII;
  58     sccb->cp_send_mask = SCLP_EVENT_MASK_MSG_ASCII;
  59
  60     sclp_service_call(SCLP_CMD_WRITE_EVENT_MASK, sccb);
  61 }
  62
  63 void sclp_setup(void)
  64 {
  65     sclp_set_write_mask();
  66 }
  67
  68 static int _strlen(const char *str)
  69 {
  70     int i;
  71     for (i = 0; *str; i++)
  72         str++;
  73     return i;
  74 }
  75
  76 long write(int fd, const void *str, size_t len)
  77 {
  78     WriteEventData *sccb = (void *)_sccb;
  79     const char *p = str;
  80     size_t data_len = 0;
  81     size_t i;
  82
  83     if (fd != 1 && fd != 2) {
  84         return -EIO;
  85     }
  86
  87     for (i = 0; i < len; i++) {
  88         if ((data_len + 1) >= SCCB_DATA_LEN) {
  89             /* We would overflow the sccb buffer, abort early */
  90             len = i;
  91             break;
  92         }
  93
  94         if (*p == '\n') {
  95             /* Terminal emulators might need \r\n, so generate it */
  96             sccb->data[data_len++] = '\r';
  97         }
  98
  99         sccb->data[data_len++] = *p;
 100         p++;
 101     }
 102
 103     sccb->h.length = sizeof(WriteEventData) + data_len;
 104     sccb->h.function_code = SCLP_FC_NORMAL_WRITE;
 105     sccb->ebh.length = sizeof(EventBufferHeader) + data_len;
 106     sccb->ebh.type = SCLP_EVENT_ASCII_CONSOLE_DATA;
 107     sccb->ebh.flags = 0;
 108
 109     sclp_service_call(SCLP_CMD_WRITE_EVENT_DATA, sccb);
 110
 111     return len;
 112 }
 113
 114 void sclp_print(const char *str)
 115 {
 116     write(1, str, _strlen(str));
 117 }
 118
 119 void sclp_get_loadparm_ascii(char *loadparm)
 120 {
 121
 122     ReadInfo *sccb = (void *)_sccb;
 123
 124     memset((char *)_sccb, 0, sizeof(ReadInfo));
 125     sccb->h.length = sizeof(ReadInfo);
 126     if (!sclp_service_call(SCLP_CMDW_READ_SCP_INFO, sccb)) {
 127         ebcdic_to_ascii((char *) sccb->loadparm, loadparm, 8);
 128     }
 129 }