arch/powerpc/cpu/mpc5xx/serial.c

   1 /*
   2  * (C) Copyright 2003
   3  * Martin Winistoerfer, martinwinistoerfer@gmx.ch.
   4  *
   5  * See file CREDITS for list of people who contributed to this
   6  * project.
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as
  10  * published by the Free Software Foundation; either version 2 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation,
  21  */
  22
  23 /*
  24  * File:                serial.c
  25  *
  26  * Discription:         Serial interface driver for SCI1 and SCI2.
  27  *                      Since this code will be called from ROM use
  28  *                      only non-static local variables.
  29  *
  30  */
  31
  32 #include <common.h>
  33 #include <watchdog.h>
  34 #include <command.h>
  35 #include <mpc5xx.h>
  36 #include <serial.h>
  37 #include <linux/compiler.h>
  38
  39 DECLARE_GLOBAL_DATA_PTR;
  40
  41 /*
  42  * Local functions
  43  */
  44
  45 static int ready_to_send(void)
  46 {
  47         volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
  48         volatile short status;
  49
  50         do {
  51 #if defined(CONFIG_5xx_CONS_SCI1)
  52                 status = immr->im_qsmcm.qsmcm_sc1sr;
  53 #else
  54                 status = immr->im_qsmcm.qsmcm_sc2sr;
  55 #endif
  56
  57 #if defined(CONFIG_WATCHDOG)
  58                 reset_5xx_watchdog (immr);
  59 #endif
  60         } while ((status & SCI_TDRE) == 0);
  61         return 1;
  62
  63 }
  64
  65 /*
  66  * Minimal global serial functions needed to use one of the SCI modules.
  67  */
  68
  69 static int mpc5xx_serial_init(void)
  70 {
  71         volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
  72
  73         serial_setbrg();
  74
  75 #if defined(CONFIG_5xx_CONS_SCI1)
  76         /* 10-Bit, 1 start bit, 8 data bit, no parity, 1 stop bit */
  77         immr->im_qsmcm.qsmcm_scc1r1 = SCI_M_10;
  78         immr->im_qsmcm.qsmcm_scc1r1 = SCI_TE | SCI_RE;
  79 #else
  80         immr->im_qsmcm.qsmcm_scc2r1 = SCI_M_10;
  81         immr->im_qsmcm.qsmcm_scc2r1 = SCI_TE | SCI_RE;
  82 #endif
  83         return 0;
  84 }
  85
  86 static void mpc5xx_serial_putc(const char c)
  87 {
  88         volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
  89
  90         /* Test for completition */
  91         if(ready_to_send()) {
  92 #if defined(CONFIG_5xx_CONS_SCI1)
  93                 immr->im_qsmcm.qsmcm_sc1dr = (short)c;
  94 #else
  95                 immr->im_qsmcm.qsmcm_sc2dr = (short)c;
  96 #endif
  97                 if(c == '\n') {
  98                         if(ready_to_send());
  99 #if defined(CONFIG_5xx_CONS_SCI1)
 100                         immr->im_qsmcm.qsmcm_sc1dr = (short)'\r';
 101 #else
 102                         immr->im_qsmcm.qsmcm_sc2dr = (short)'\r';
 103 #endif
 104                 }
 105         }
 106 }
 107
 108 static int mpc5xx_serial_getc(void)
 109 {
 110         volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
 111         volatile short status;
 112         unsigned char tmp;
 113
 114         /* New data ? */
 115         do {
 116 #if defined(CONFIG_5xx_CONS_SCI1)
 117                 status = immr->im_qsmcm.qsmcm_sc1sr;
 118 #else
 119                 status = immr->im_qsmcm.qsmcm_sc2sr;
 120 #endif
 121
 122 #if defined(CONFIG_WATCHDOG)
 123                 reset_5xx_watchdog (immr);
 124 #endif
 125         } while ((status & SCI_RDRF) == 0);
 126
 127         /* Read data */
 128 #if defined(CONFIG_5xx_CONS_SCI1)
 129         tmp = (unsigned char)(immr->im_qsmcm.qsmcm_sc1dr & SCI_SCXDR_MK);
 130 #else
 131         tmp = (unsigned char)( immr->im_qsmcm.qsmcm_sc2dr & SCI_SCXDR_MK);
 132 #endif
 133         return  tmp;
 134 }
 135
 136 static int mpc5xx_serial_tstc(void)
 137 {
 138         volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
 139         short status;
 140
 141         /* New data character ? */
 142 #if defined(CONFIG_5xx_CONS_SCI1)
 143         status = immr->im_qsmcm.qsmcm_sc1sr;
 144 #else
 145         status = immr->im_qsmcm.qsmcm_sc2sr;
 146 #endif
 147         return (status & SCI_RDRF);
 148 }
 149
 150 static void mpc5xx_serial_setbrg(void)
 151 {
 152         volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
 153         short scxbr;
 154
 155         /* Set baudrate */
 156         scxbr = (gd->cpu_clk / (32 * gd->baudrate));
 157 #if defined(CONFIG_5xx_CONS_SCI1)
 158         immr->im_qsmcm.qsmcm_scc1r0 = (scxbr & SCI_SCXBR_MK);
 159 #else
 160         immr->im_qsmcm.qsmcm_scc2r0 = (scxbr & SCI_SCXBR_MK);
 161 #endif
 162 }
 163
 164 static struct serial_device mpc5xx_serial_drv = {
 165         .name   = "mpc5xx_serial",
 166         .start  = mpc5xx_serial_init,
 167         .stop   = NULL,
 168         .setbrg = mpc5xx_serial_setbrg,
 169         .putc   = mpc5xx_serial_putc,
 170         .puts   = default_serial_puts,
 171         .getc   = mpc5xx_serial_getc,
 172         .tstc   = mpc5xx_serial_tstc,
 173 };
 174
 175 void mpc5xx_serial_initialize(void)
 176 {
 177         serial_register(&mpc5xx_serial_drv);
 178 }
 179
 180 __weak struct serial_device *default_serial_console(void)
 181 {
 182         return &mpc5xx_serial_drv;
 183 }