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 #define ULITE_CONTROL_RST_TX    0x01
  22 #define ULITE_CONTROL_RST_RX    0x02
  23
  24 struct uartlite {
  25         unsigned int rx_fifo;
  26         unsigned int tx_fifo;
  27         unsigned int status;
  28         unsigned int control;
  29 };
  30
  31 static struct uartlite *userial_ports[4] = {
  32 #ifdef XILINX_UARTLITE_BASEADDR
  33         [0] = (struct uartlite *)XILINX_UARTLITE_BASEADDR,
  34 #endif
  35 #ifdef XILINX_UARTLITE_BASEADDR1
  36         [1] = (struct uartlite *)XILINX_UARTLITE_BASEADDR1,
  37 #endif
  38 #ifdef XILINX_UARTLITE_BASEADDR2
  39         [2] = (struct uartlite *)XILINX_UARTLITE_BASEADDR2,
  40 #endif
  41 #ifdef XILINX_UARTLITE_BASEADDR3
  42         [3] = (struct uartlite *)XILINX_UARTLITE_BASEADDR3
  43 #endif
  44 };
  45
  46 static void uartlite_serial_putc(const char c, const int port)
  47 {
  48         struct uartlite *regs = userial_ports[port];
  49
  50         if (c == '\n')
  51                 uartlite_serial_putc('\r', port);
  52
  53         while (in_be32(&regs->status) & SR_TX_FIFO_FULL)
  54                 ;
  55         out_be32(&regs->tx_fifo, c & 0xff);
  56 }
  57
  58 static void uartlite_serial_puts(const char *s, const int port)
  59 {
  60         while (*s)
  61                 uartlite_serial_putc(*s++, port);
  62 }
  63
  64 static int uartlite_serial_getc(const int port)
  65 {
  66         struct uartlite *regs = userial_ports[port];
  67
  68         while (!(in_be32(&regs->status) & SR_RX_FIFO_VALID_DATA))
  69                 ;
  70         return in_be32(&regs->rx_fifo) & 0xff;
  71 }
  72
  73 static int uartlite_serial_tstc(const int port)
  74 {
  75         struct uartlite *regs = userial_ports[port];
  76
  77         return in_be32(&regs->status) & SR_RX_FIFO_VALID_DATA;
  78 }
  79
  80 static int uartlite_serial_init(const int port)
  81 {
  82         struct uartlite *regs = userial_ports[port];
  83
  84         if (regs) {
  85                 out_be32(&regs->control, 0);
  86                 out_be32(&regs->control,
  87                          ULITE_CONTROL_RST_RX | ULITE_CONTROL_RST_TX);
  88                 in_be32(&regs->control);
  89                 return 0;
  90         }
  91
  92         return -1;
  93 }
  94
  95 /* Multi serial device functions */
  96 #define DECLARE_ESERIAL_FUNCTIONS(port) \
  97         static int userial##port##_init(void) \
  98                                 { return uartlite_serial_init(port); } \
  99         static void userial##port##_setbrg(void) {} \
 100         static int userial##port##_getc(void) \
 101                                 { return uartlite_serial_getc(port); } \
 102         static int userial##port##_tstc(void) \
 103                                 { return uartlite_serial_tstc(port); } \
 104         static void userial##port##_putc(const char c) \
 105                                 { uartlite_serial_putc(c, port); } \
 106         static void userial##port##_puts(const char *s) \
 107                                 { uartlite_serial_puts(s, port); }
 108
 109 /* Serial device descriptor */
 110 #define INIT_ESERIAL_STRUCTURE(port, __name) {  \
 111         .name   = __name,                       \
 112         .start  = userial##port##_init,         \
 113         .stop   = NULL,                         \
 114         .setbrg = userial##port##_setbrg,       \
 115         .getc   = userial##port##_getc,         \
 116         .tstc   = userial##port##_tstc,         \
 117         .putc   = userial##port##_putc,         \
 118         .puts   = userial##port##_puts,         \
 119 }
 120
 121 DECLARE_ESERIAL_FUNCTIONS(0);
 122 struct serial_device uartlite_serial0_device =
 123         INIT_ESERIAL_STRUCTURE(0, "ttyUL0");
 124 DECLARE_ESERIAL_FUNCTIONS(1);
 125 struct serial_device uartlite_serial1_device =
 126         INIT_ESERIAL_STRUCTURE(1, "ttyUL1");
 127 DECLARE_ESERIAL_FUNCTIONS(2);
 128 struct serial_device uartlite_serial2_device =
 129         INIT_ESERIAL_STRUCTURE(2, "ttyUL2");
 130 DECLARE_ESERIAL_FUNCTIONS(3);
 131 struct serial_device uartlite_serial3_device =
 132         INIT_ESERIAL_STRUCTURE(3, "ttyUL3");
 133
 134 __weak struct serial_device *default_serial_console(void)
 135 {
 136         if (userial_ports[0])
 137                 return &uartlite_serial0_device;
 138         if (userial_ports[1])
 139                 return &uartlite_serial1_device;
 140         if (userial_ports[2])
 141                 return &uartlite_serial2_device;
 142         if (userial_ports[3])
 143                 return &uartlite_serial3_device;
 144
 145         return NULL;
 146 }
 147
 148 void uartlite_serial_initialize(void)
 149 {
 150 #ifdef XILINX_UARTLITE_BASEADDR
 151         serial_register(&uartlite_serial0_device);
 152 #endif /* XILINX_UARTLITE_BASEADDR */
 153 #ifdef XILINX_UARTLITE_BASEADDR1
 154         serial_register(&uartlite_serial1_device);
 155 #endif /* XILINX_UARTLITE_BASEADDR1 */
 156 #ifdef XILINX_UARTLITE_BASEADDR2
 157         serial_register(&uartlite_serial2_device);
 158 #endif /* XILINX_UARTLITE_BASEADDR2 */
 159 #ifdef XILINX_UARTLITE_BASEADDR3
 160         serial_register(&uartlite_serial3_device);
 161 #endif /* XILINX_UARTLITE_BASEADDR3 */
 162 }