arch/arm/mach-omap2/serial.c

   1 /*
   2  * arch/arm/mach-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 #include <linux/clk.h>
  20 #include <linux/io.h>
  21
  22 #include <mach/common.h>
  23 #include <mach/board.h>
  24
  25 static struct clk * uart1_ick = NULL;
  26 static struct clk * uart1_fck = NULL;
  27 static struct clk * uart2_ick = NULL;
  28 static struct clk * uart2_fck = NULL;
  29 static struct clk * uart3_ick = NULL;
  30 static struct clk * uart3_fck = NULL;
  31
  32 static struct plat_serial8250_port serial_platform_data[] = {
  33         {
  34                 .membase        = (char *)IO_ADDRESS(OMAP_UART1_BASE),
  35                 .mapbase        = (unsigned long)OMAP_UART1_BASE,
  36                 .irq            = 72,
  37                 .flags          = UPF_BOOT_AUTOCONF,
  38                 .iotype         = UPIO_MEM,
  39                 .regshift       = 2,
  40                 .uartclk        = OMAP16XX_BASE_BAUD * 16,
  41         }, {
  42                 .membase        = (char *)IO_ADDRESS(OMAP_UART2_BASE),
  43                 .mapbase        = (unsigned long)OMAP_UART2_BASE,
  44                 .irq            = 73,
  45                 .flags          = UPF_BOOT_AUTOCONF,
  46                 .iotype         = UPIO_MEM,
  47                 .regshift       = 2,
  48                 .uartclk        = OMAP16XX_BASE_BAUD * 16,
  49         }, {
  50                 .membase        = (char *)IO_ADDRESS(OMAP_UART3_BASE),
  51                 .mapbase        = (unsigned long)OMAP_UART3_BASE,
  52                 .irq            = 74,
  53                 .flags          = UPF_BOOT_AUTOCONF,
  54                 .iotype         = UPIO_MEM,
  55                 .regshift       = 2,
  56                 .uartclk        = OMAP16XX_BASE_BAUD * 16,
  57         }, {
  58                 .flags          = 0
  59         }
  60 };
  61
  62 static inline unsigned int serial_read_reg(struct plat_serial8250_port *up,
  63                                            int offset)
  64 {
  65         offset <<= up->regshift;
  66         return (unsigned int)__raw_readb(up->membase + offset);
  67 }
  68
  69 static inline void serial_write_reg(struct plat_serial8250_port *p, int offset,
  70                                     int value)
  71 {
  72         offset <<= p->regshift;
  73         __raw_writeb(value, (unsigned long)(p->membase + offset));
  74 }
  75
  76 /*
  77  * Internal UARTs need to be initialized for the 8250 autoconfig to work
  78  * properly. Note that the TX watermark initialization may not be needed
  79  * once the 8250.c watermark handling code is merged.
  80  */
  81 static inline void __init omap_serial_reset(struct plat_serial8250_port *p)
  82 {
  83         serial_write_reg(p, UART_OMAP_MDR1, 0x07);
  84         serial_write_reg(p, UART_OMAP_SCR, 0x08);
  85         serial_write_reg(p, UART_OMAP_MDR1, 0x00);
  86         serial_write_reg(p, UART_OMAP_SYSC, (0x02 << 3) | (1 << 2) | (1 << 0));
  87 }
  88
  89 void __init omap_serial_init()
  90 {
  91         int i;
  92         const struct omap_uart_config *info;
  93
  94         /*
  95          * Make sure the serial ports are muxed on at this point.
  96          * You have to mux them off in device drivers later on
  97          * if not needed.
  98          */
  99
 100         info = omap_get_config(OMAP_TAG_UART,
 101                                struct omap_uart_config);
 102
 103         if (info == NULL)
 104                 return;
 105
 106         for (i = 0; i < OMAP_MAX_NR_PORTS; i++) {
 107                 struct plat_serial8250_port *p = serial_platform_data + i;
 108
 109                 if (!(info->enabled_uarts & (1 << i))) {
 110                         p->membase = 0;
 111                         p->mapbase = 0;
 112                         continue;
 113                 }
 114
 115                 switch (i) {
 116                 case 0:
 117                         uart1_ick = clk_get(NULL, "uart1_ick");
 118                         if (IS_ERR(uart1_ick))
 119                                 printk("Could not get uart1_ick\n");
 120                         else {
 121                                 clk_enable(uart1_ick);
 122                         }
 123
 124                         uart1_fck = clk_get(NULL, "uart1_fck");
 125                         if (IS_ERR(uart1_fck))
 126                                 printk("Could not get uart1_fck\n");
 127                         else {
 128                                 clk_enable(uart1_fck);
 129                         }
 130                         break;
 131                 case 1:
 132                         uart2_ick = clk_get(NULL, "uart2_ick");
 133                         if (IS_ERR(uart2_ick))
 134                                 printk("Could not get uart2_ick\n");
 135                         else {
 136                                 clk_enable(uart2_ick);
 137                         }
 138
 139                         uart2_fck = clk_get(NULL, "uart2_fck");
 140                         if (IS_ERR(uart2_fck))
 141                                 printk("Could not get uart2_fck\n");
 142                         else {
 143                                 clk_enable(uart2_fck);
 144                         }
 145                         break;
 146                 case 2:
 147                         uart3_ick = clk_get(NULL, "uart3_ick");
 148                         if (IS_ERR(uart3_ick))
 149                                 printk("Could not get uart3_ick\n");
 150                         else {
 151                                 clk_enable(uart3_ick);
 152                         }
 153
 154                         uart3_fck = clk_get(NULL, "uart3_fck");
 155                         if (IS_ERR(uart3_fck))
 156                                 printk("Could not get uart3_fck\n");
 157                         else {
 158                                 clk_enable(uart3_fck);
 159                         }
 160                         break;
 161                 }
 162
 163                 omap_serial_reset(p);
 164         }
 165 }
 166
 167 static struct platform_device serial_device = {
 168         .name                   = "serial8250",
 169         .id                     = PLAT8250_DEV_PLATFORM,
 170         .dev                    = {
 171                 .platform_data  = serial_platform_data,
 172         },
 173 };
 174
 175 static int __init omap_init(void)
 176 {
 177         return platform_device_register(&serial_device);
 178 }
 179 arch_initcall(omap_init);