post/cpu/ppc4xx/uart.c

   1 /*
   2  * (C) Copyright 2007
   3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   4  *
   5  * Author: Igor Lisitsin <igor@emcraft.com>
   6  *
   7  * Copyright 2010, Stefan Roese, DENX Software Engineering, sr@denx.de
   8  *
   9  * SPDX-License-Identifier:     GPL-2.0+
  10  */
  11
  12 #include <common.h>
  13 #include <asm/ppc4xx.h>
  14 #include <ns16550.h>
  15 #include <asm/io.h>
  16 #include <serial.h>
  17
  18 /*
  19  * UART test
  20  *
  21  * The controllers are configured to loopback mode and several
  22  * characters are transmitted.
  23  */
  24
  25 #include <post.h>
  26
  27 #if CONFIG_POST & CONFIG_SYS_POST_UART
  28
  29 /*
  30  * This table defines the UART's that should be tested and can
  31  * be overridden in the board config file
  32  */
  33 #ifndef CONFIG_SYS_POST_UART_TABLE
  34 #define CONFIG_SYS_POST_UART_TABLE      { CONFIG_SYS_NS16550_COM1, \
  35                         CONFIG_SYS_NS16550_COM2, CONFIG_SYS_NS16550_COM3, \
  36                         CONFIG_SYS_NS16550_COM4 }
  37 #endif
  38
  39 DECLARE_GLOBAL_DATA_PTR;
  40
  41 static int test_ctlr (struct NS16550 *com_port, int index)
  42 {
  43         int res = -1;
  44         char test_str[] = "*** UART Test String ***\r\n";
  45         int i;
  46         int divisor;
  47
  48         divisor = (get_serial_clock() + (gd->baudrate * (16 / 2))) /
  49                 (16 * gd->baudrate);
  50         NS16550_init(com_port, divisor);
  51
  52         /*
  53          * Set internal loopback mode in UART
  54          */
  55         out_8(&com_port->mcr, in_8(&com_port->mcr) | UART_MCR_LOOP);
  56
  57         /* Reset FIFOs */
  58         out_8(&com_port->fcr, UART_FCR_RXSR | UART_FCR_TXSR);
  59         udelay(100);
  60
  61         /* Flush RX-FIFO */
  62         while (NS16550_tstc(com_port))
  63                 NS16550_getc(com_port);
  64
  65         for (i = 0; i < sizeof (test_str) - 1; i++) {
  66                 NS16550_putc(com_port, test_str[i]);
  67                 if (NS16550_getc(com_port) != test_str[i])
  68                         goto done;
  69         }
  70         res = 0;
  71 done:
  72         if (res)
  73                 post_log ("uart%d test failed\n", index);
  74
  75         return res;
  76 }
  77
  78 int uart_post_test (int flags)
  79 {
  80         int i, res = 0;
  81         static unsigned long base[] = CONFIG_SYS_POST_UART_TABLE;
  82
  83         for (i = 0; i < ARRAY_SIZE(base); i++) {
  84                 if (test_ctlr((struct NS16550 *)base[i], i))
  85                         res = -1;
  86         }
  87         serial_reinit_all ();
  88
  89         return res;
  90 }
  91
  92 #endif /* CONFIG_POST & CONFIG_SYS_POST_UART */