drivers/serial/serial_xuartlite.c

   1 /*
   2  * (C) Copyright 2008-2011 Michal Simek <monstr@monstr.eu>
   3  * Clean driver and add xilinx constant from header file
   4  *
   5  * (C) Copyright 2004 Atmark Techno, Inc.
   6  * Yasushi SHOJI <yashi@atmark-techno.com>
   7  *
   8  * SPDX-License-Identifier:     GPL-2.0+
   9  */
  10
  11 #include <config.h>
  12 #include <common.h>
  13 #include <asm/io.h>
  14 #include <linux/compiler.h>
  15 #include <serial.h>
  16
  17 #define SR_TX_FIFO_FULL         0x08 /* transmit FIFO full */
  18 #define SR_RX_FIFO_VALID_DATA   0x01 /* data in receive FIFO */
  19 #define SR_RX_FIFO_FULL         0x02 /* receive FIFO full */
  20
  21 struct uartlite {
  22         unsigned int rx_fifo;
  23         unsigned int tx_fifo;
  24         unsigned int status;
  25 };
  26
  27 static struct uartlite *userial_ports[4] = {
  28 #ifdef XILINX_UARTLITE_BASEADDR
  29         [0] = (struct uartlite *)XILINX_UARTLITE_BASEADDR,
  30 #endif
  31 #ifdef XILINX_UARTLITE_BASEADDR1
  32         [1] = (struct uartlite *)XILINX_UARTLITE_BASEADDR1,
  33 #endif
  34 #ifdef XILINX_UARTLITE_BASEADDR2
  35         [2] = (struct uartlite *)XILINX_UARTLITE_BASEADDR2,
  36 #endif
  37 #ifdef XILINX_UARTLITE_BASEADDR3
  38         [3] = (struct uartlite *)XILINX_UARTLITE_BASEADDR3
  39 #endif
  40 };
  41
  42 static void uartlite_serial_putc(const char c, const int port)
  43 {
  44         struct uartlite *regs = userial_ports[port];
  45
  46         if (c == '\n')
  47                 uartlite_serial_putc('\r', port);
  48
  49         while (in_be32(&regs->status) & SR_TX_FIFO_FULL)
  50                 ;
  51         out_be32(&regs->tx_fifo, c & 0xff);
  52 }
  53
  54 static void uartlite_serial_puts(const char *s, const int port)
  55 {
  56         while (*s)
  57                 uartlite_serial_putc(*s++, port);
  58 }
  59
  60 static int uartlite_serial_getc(const int port)
  61 {
  62         struct uartlite *regs = userial_ports[port];
  63
  64         while (!(in_be32(&regs->status) & SR_RX_FIFO_VALID_DATA))
  65                 ;
  66         return in_be32(&regs->rx_fifo) & 0xff;
  67 }
  68
  69 static int uartlite_serial_tstc(const int port)
  70 {
  71         struct uartlite *regs = userial_ports[port];
  72
  73         return in_be32(&regs->status) & SR_RX_FIFO_VALID_DATA;
  74 }
  75
  76 static int uartlite_serial_init(const int port)
  77 {
  78         if (userial_ports[port])
  79                 return 0;
  80         return -1;
  81 }
  82
  83 /* Multi serial device functions */
  84 #define DECLARE_ESERIAL_FUNCTIONS(port) \
  85         static int userial##port##_init(void) \
  86                                 { return uartlite_serial_init(port); } \
  87         static void userial##port##_setbrg(void) {} \
  88         static int userial##port##_getc(void) \
  89                                 { return uartlite_serial_getc(port); } \
  90         static int userial##port##_tstc(void) \
  91                                 { return uartlite_serial_tstc(port); } \
  92         static void userial##port##_putc(const char c) \
  93                                 { uartlite_serial_putc(c, port); } \
  94         static void userial##port##_puts(const char *s) \
  95                                 { uartlite_serial_puts(s, port); }
  96
  97 /* Serial device descriptor */
  98 #define INIT_ESERIAL_STRUCTURE(port, __name) {  \
  99         .name   = __name,                       \
 100         .start  = userial##port##_init,         \
 101         .stop   = NULL,                         \
 102         .setbrg = userial##port##_setbrg,       \
 103         .getc   = userial##port##_getc,         \
 104         .tstc   = userial##port##_tstc,         \
 105         .putc   = userial##port##_putc,         \
 106         .puts   = userial##port##_puts,         \
 107 }
 108
 109 DECLARE_ESERIAL_FUNCTIONS(0);
 110 struct serial_device uartlite_serial0_device =
 111         INIT_ESERIAL_STRUCTURE(0, "ttyUL0");
 112 DECLARE_ESERIAL_FUNCTIONS(1);
 113 struct serial_device uartlite_serial1_device =
 114         INIT_ESERIAL_STRUCTURE(1, "ttyUL1");
 115 DECLARE_ESERIAL_FUNCTIONS(2);
 116 struct serial_device uartlite_serial2_device =
 117         INIT_ESERIAL_STRUCTURE(2, "ttyUL2");
 118 DECLARE_ESERIAL_FUNCTIONS(3);
 119 struct serial_device uartlite_serial3_device =
 120         INIT_ESERIAL_STRUCTURE(3, "ttyUL3");
 121
 122 __weak struct serial_device *default_serial_console(void)
 123 {
 124         if (userial_ports[0])
 125                 return &uartlite_serial0_device;
 126         if (userial_ports[1])
 127                 return &uartlite_serial1_device;
 128         if (userial_ports[2])
 129                 return &uartlite_serial2_device;
 130         if (userial_ports[3])
 131                 return &uartlite_serial3_device;
 132
 133         return NULL;
 134 }
 135
 136 void uartlite_serial_initialize(void)
 137 {
 138 #ifdef XILINX_UARTLITE_BASEADDR
 139         serial_register(&uartlite_serial0_device);
 140 #endif /* XILINX_UARTLITE_BASEADDR */
 141 #ifdef XILINX_UARTLITE_BASEADDR1
 142         serial_register(&uartlite_serial1_device);
 143 #endif /* XILINX_UARTLITE_BASEADDR1 */
 144 #ifdef XILINX_UARTLITE_BASEADDR2
 145         serial_register(&uartlite_serial2_device);
 146 #endif /* XILINX_UARTLITE_BASEADDR2 */
 147 #ifdef XILINX_UARTLITE_BASEADDR3
 148         serial_register(&uartlite_serial3_device);
 149 #endif /* XILINX_UARTLITE_BASEADDR3 */
 150 }