arch/arm/plat-samsung/init.c

   1 /* linux/arch/arm/plat-s3c/init.c
   2  *
   3  * Copyright (c) 2008 Simtec Electronics
   4  *      Ben Dooks <ben@simtec.co.uk>
   5  *      http://armlinux.simtec.co.uk/
   6  *
   7  * S3C series CPU initialisation
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12 */
  13
  14 /*
  15  * NOTE: Code in this file is not used on S3C64xx when booting with
  16  * Device Tree support.
  17  */
  18
  19 #include <linux/init.h>
  20 #include <linux/module.h>
  21 #include <linux/interrupt.h>
  22 #include <linux/ioport.h>
  23 #include <linux/serial_core.h>
  24 #include <linux/platform_device.h>
  25 #include <linux/of.h>
  26
  27 #include <mach/hardware.h>
  28
  29 #include <asm/mach/arch.h>
  30 #include <asm/mach/map.h>
  31
  32 #include <plat/cpu.h>
  33 #include <plat/devs.h>
  34 #include <plat/clock.h>
  35
  36 #include <plat/regs-serial.h>
  37
  38 static struct cpu_table *cpu;
  39
  40 static struct cpu_table * __init s3c_lookup_cpu(unsigned long idcode,
  41                                                 struct cpu_table *tab,
  42                                                 unsigned int count)
  43 {
  44         for (; count != 0; count--, tab++) {
  45                 if ((idcode & tab->idmask) == (tab->idcode & tab->idmask))
  46                         return tab;
  47         }
  48
  49         return NULL;
  50 }
  51
  52 void __init s3c_init_cpu(unsigned long idcode,
  53                          struct cpu_table *cputab, unsigned int cputab_size)
  54 {
  55         cpu = s3c_lookup_cpu(idcode, cputab, cputab_size);
  56
  57         if (cpu == NULL) {
  58                 printk(KERN_ERR "Unknown CPU type 0x%08lx\n", idcode);
  59                 panic("Unknown S3C24XX CPU");
  60         }
  61
  62         printk("CPU %s (id 0x%08lx)\n", cpu->name, idcode);
  63
  64         if (cpu->init == NULL) {
  65                 printk(KERN_ERR "CPU %s support not enabled\n", cpu->name);
  66                 panic("Unsupported Samsung CPU");
  67         }
  68
  69         if (cpu->map_io)
  70                 cpu->map_io();
  71 }
  72
  73 /* s3c24xx_init_clocks
  74  *
  75  * Initialise the clock subsystem and associated information from the
  76  * given master crystal value.
  77  *
  78  * xtal  = 0 -> use default PLL crystal value (normally 12MHz)
  79  *      != 0 -> PLL crystal value in Hz
  80 */
  81
  82 void __init s3c24xx_init_clocks(int xtal)
  83 {
  84         if (xtal == 0)
  85                 xtal = 12*1000*1000;
  86
  87         if (cpu == NULL)
  88                 panic("s3c24xx_init_clocks: no cpu setup?\n");
  89
  90         if (cpu->init_clocks == NULL)
  91                 panic("s3c24xx_init_clocks: cpu has no clock init\n");
  92         else
  93                 (cpu->init_clocks)(xtal);
  94 }
  95
  96 /* uart management */
  97 #if IS_ENABLED(CONFIG_SAMSUNG_ATAGS)
  98 static int nr_uarts __initdata = 0;
  99
 100 static struct s3c2410_uartcfg uart_cfgs[CONFIG_SERIAL_SAMSUNG_UARTS];
 101
 102 /* s3c24xx_init_uartdevs
 103  *
 104  * copy the specified platform data and configuration into our central
 105  * set of devices, before the data is thrown away after the init process.
 106  *
 107  * This also fills in the array passed to the serial driver for the
 108  * early initialisation of the console.
 109 */
 110
 111 void __init s3c24xx_init_uartdevs(char *name,
 112                                   struct s3c24xx_uart_resources *res,
 113                                   struct s3c2410_uartcfg *cfg, int no)
 114 {
 115         struct platform_device *platdev;
 116         struct s3c2410_uartcfg *cfgptr = uart_cfgs;
 117         struct s3c24xx_uart_resources *resp;
 118         int uart;
 119
 120         memcpy(cfgptr, cfg, sizeof(struct s3c2410_uartcfg) * no);
 121
 122         for (uart = 0; uart < no; uart++, cfg++, cfgptr++) {
 123                 platdev = s3c24xx_uart_src[cfgptr->hwport];
 124
 125                 resp = res + cfgptr->hwport;
 126
 127                 s3c24xx_uart_devs[uart] = platdev;
 128
 129                 platdev->name = name;
 130                 platdev->resource = resp->resources;
 131                 platdev->num_resources = resp->nr_resources;
 132
 133                 platdev->dev.platform_data = cfgptr;
 134         }
 135
 136         nr_uarts = no;
 137 }
 138
 139 void __init s3c24xx_init_uarts(struct s3c2410_uartcfg *cfg, int no)
 140 {
 141         if (cpu == NULL)
 142                 return;
 143
 144         if (cpu->init_uarts == NULL && IS_ENABLED(CONFIG_SAMSUNG_ATAGS)) {
 145                 printk(KERN_ERR "s3c24xx_init_uarts: cpu has no uart init\n");
 146         } else
 147                 (cpu->init_uarts)(cfg, no);
 148 }
 149 #endif
 150
 151 static int __init s3c_arch_init(void)
 152 {
 153         int ret;
 154
 155         // do the correct init for cpu
 156
 157         if (cpu == NULL) {
 158                 /* Not needed when booting with device tree. */
 159                 if (of_have_populated_dt())
 160                         return 0;
 161                 panic("s3c_arch_init: NULL cpu\n");
 162         }
 163
 164         ret = (cpu->init)();
 165         if (ret != 0)
 166                 return ret;
 167 #if IS_ENABLED(CONFIG_SAMSUNG_ATAGS)
 168         ret = platform_add_devices(s3c24xx_uart_devs, nr_uarts);
 169 #endif
 170         return ret;
 171 }
 172
 173 arch_initcall(s3c_arch_init);