arch/arm/mach-omap2/serial.c

   1 /*
   2  * arch/arm/mach-omap/omap2/serial.c
   3  *
   4  * OMAP2 serial support.
   5  *
   6  * Copyright (C) 2005 Nokia Corporation
   7  * Author: Paul Mundt <paul.mundt@nokia.com>
   8  *
   9  * Based off of arch/arm/mach-omap/omap1/serial.c
  10  *
  11  * This file is subject to the terms and conditions of the GNU General Public
  12  * License. See the file "COPYING" in the main directory of this archive
  13  * for more details.
  14  */
  15 #include <linux/kernel.h>
  16 #include <linux/init.h>
  17 #include <linux/serial_8250.h>
  18 #include <linux/serial_reg.h>
  19
  20 #include <asm/io.h>
  21
  22 #include <asm/arch/common.h>
  23 #include <asm/arch/board.h>
  24
  25 static struct plat_serial8250_port serial_platform_data[] = {
  26         {
  27                 .membase        = (char *)IO_ADDRESS(OMAP_UART1_BASE),
  28                 .mapbase        = (unsigned long)OMAP_UART1_BASE,
  29                 .irq            = 72,
  30                 .flags          = UPF_BOOT_AUTOCONF,
  31                 .iotype         = UPIO_MEM,
  32                 .regshift       = 2,
  33                 .uartclk        = OMAP16XX_BASE_BAUD * 16,
  34         }, {
  35                 .membase        = (char *)IO_ADDRESS(OMAP_UART2_BASE),
  36                 .mapbase        = (unsigned long)OMAP_UART2_BASE,
  37                 .irq            = 73,
  38                 .flags          = UPF_BOOT_AUTOCONF,
  39                 .iotype         = UPIO_MEM,
  40                 .regshift       = 2,
  41                 .uartclk        = OMAP16XX_BASE_BAUD * 16,
  42         }, {
  43                 .membase        = (char *)IO_ADDRESS(OMAP_UART3_BASE),
  44                 .mapbase        = (unsigned long)OMAP_UART3_BASE,
  45                 .irq            = 74,
  46                 .flags          = UPF_BOOT_AUTOCONF,
  47                 .iotype         = UPIO_MEM,
  48                 .regshift       = 2,
  49                 .uartclk        = OMAP16XX_BASE_BAUD * 16,
  50         }, {
  51                 .flags          = 0
  52         }
  53 };
  54
  55 static inline unsigned int serial_read_reg(struct plat_serial8250_port *up,
  56                                            int offset)
  57 {
  58         offset <<= up->regshift;
  59         return (unsigned int)__raw_readb(up->membase + offset);
  60 }
  61
  62 static inline void serial_write_reg(struct plat_serial8250_port *p, int offset,
  63                                     int value)
  64 {
  65         offset <<= p->regshift;
  66         __raw_writeb(value, (unsigned long)(p->membase + offset));
  67 }
  68
  69 /*
  70  * Internal UARTs need to be initialized for the 8250 autoconfig to work
  71  * properly. Note that the TX watermark initialization may not be needed
  72  * once the 8250.c watermark handling code is merged.
  73  */
  74 static inline void __init omap_serial_reset(struct plat_serial8250_port *p)
  75 {
  76         serial_write_reg(p, UART_OMAP_MDR1, 0x07);
  77         serial_write_reg(p, UART_OMAP_SCR, 0x08);
  78         serial_write_reg(p, UART_OMAP_MDR1, 0x00);
  79         serial_write_reg(p, UART_OMAP_SYSC, 0x01);
  80 }
  81
  82 void __init omap_serial_init()
  83 {
  84         int i;
  85         const struct omap_uart_config *info;
  86
  87         /*
  88          * Make sure the serial ports are muxed on at this point.
  89          * You have to mux them off in device drivers later on
  90          * if not needed.
  91          */
  92
  93         info = omap_get_config(OMAP_TAG_UART,
  94                                struct omap_uart_config);
  95
  96         if (info == NULL)
  97                 return;
  98
  99         for (i = 0; i < OMAP_MAX_NR_PORTS; i++) {
 100                 struct plat_serial8250_port *p = serial_platform_data + i;
 101
 102                 if (!(info->enabled_uarts & (1 << i))) {
 103                         p->membase = 0;
 104                         p->mapbase = 0;
 105                         continue;
 106                 }
 107
 108                 omap_serial_reset(p);
 109         }
 110 }
 111
 112 static struct platform_device serial_device = {
 113         .name                   = "serial8250",
 114         .id                     = 0,
 115         .dev                    = {
 116                 .platform_data  = serial_platform_data,
 117         },
 118 };
 119
 120 static int __init omap_init(void)
 121 {
 122         return platform_device_register(&serial_device);
 123 }
 124 arch_initcall(omap_init);