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/serial_s3c.h>
  25 #include <linux/platform_device.h>
  26 #include <linux/of.h>
  27
  28 #include <asm/mach/arch.h>
  29 #include <asm/mach/map.h>
  30
  31 #include <plat/cpu.h>
  32 #include <plat/devs.h>
  33
  34 static struct cpu_table *cpu;
  35
  36 static struct cpu_table * __init s3c_lookup_cpu(unsigned long idcode,
  37                                                 struct cpu_table *tab,
  38                                                 unsigned int count)
  39 {
  40         for (; count != 0; count--, tab++) {
  41                 if ((idcode & tab->idmask) == (tab->idcode & tab->idmask))
  42                         return tab;
  43         }
  44
  45         return NULL;
  46 }
  47
  48 void __init s3c_init_cpu(unsigned long idcode,
  49                          struct cpu_table *cputab, unsigned int cputab_size)
  50 {
  51         cpu = s3c_lookup_cpu(idcode, cputab, cputab_size);
  52
  53         if (cpu == NULL) {
  54                 printk(KERN_ERR "Unknown CPU type 0x%08lx\n", idcode);
  55                 panic("Unknown S3C24XX CPU");
  56         }
  57
  58         printk("CPU %s (id 0x%08lx)\n", cpu->name, idcode);
  59
  60         if (cpu->init == NULL) {
  61                 printk(KERN_ERR "CPU %s support not enabled\n", cpu->name);
  62                 panic("Unsupported Samsung CPU");
  63         }
  64
  65         if (cpu->map_io)
  66                 cpu->map_io();
  67 }
  68
  69 /* s3c24xx_init_clocks
  70  *
  71  * Initialise the clock subsystem and associated information from the
  72  * given master crystal value.
  73  *
  74  * xtal  = 0 -> use default PLL crystal value (normally 12MHz)
  75  *      != 0 -> PLL crystal value in Hz
  76 */
  77
  78 void __init s3c24xx_init_clocks(int xtal)
  79 {
  80         if (xtal == 0)
  81                 xtal = 12*1000*1000;
  82
  83         if (cpu == NULL)
  84                 panic("s3c24xx_init_clocks: no cpu setup?\n");
  85
  86         if (cpu->init_clocks == NULL)
  87                 panic("s3c24xx_init_clocks: cpu has no clock init\n");
  88         else
  89                 (cpu->init_clocks)(xtal);
  90 }
  91
  92 /* uart management */
  93 #if IS_ENABLED(CONFIG_SAMSUNG_ATAGS)
  94 static int nr_uarts __initdata = 0;
  95
  96 #ifdef CONFIG_SERIAL_SAMSUNG_UARTS
  97 static struct s3c2410_uartcfg uart_cfgs[CONFIG_SERIAL_SAMSUNG_UARTS];
  98 #endif
  99
 100 /* s3c24xx_init_uartdevs
 101  *
 102  * copy the specified platform data and configuration into our central
 103  * set of devices, before the data is thrown away after the init process.
 104  *
 105  * This also fills in the array passed to the serial driver for the
 106  * early initialisation of the console.
 107 */
 108
 109 void __init s3c24xx_init_uartdevs(char *name,
 110                                   struct s3c24xx_uart_resources *res,
 111                                   struct s3c2410_uartcfg *cfg, int no)
 112 {
 113 #ifdef CONFIG_SERIAL_SAMSUNG_UARTS
 114         struct platform_device *platdev;
 115         struct s3c2410_uartcfg *cfgptr = uart_cfgs;
 116         struct s3c24xx_uart_resources *resp;
 117         int uart;
 118
 119         memcpy(cfgptr, cfg, sizeof(struct s3c2410_uartcfg) * no);
 120
 121         for (uart = 0; uart < no; uart++, cfg++, cfgptr++) {
 122                 platdev = s3c24xx_uart_src[cfgptr->hwport];
 123
 124                 resp = res + cfgptr->hwport;
 125
 126                 s3c24xx_uart_devs[uart] = platdev;
 127
 128                 platdev->name = name;
 129                 platdev->resource = resp->resources;
 130                 platdev->num_resources = resp->nr_resources;
 131
 132                 platdev->dev.platform_data = cfgptr;
 133         }
 134
 135         nr_uarts = no;
 136 #endif
 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         /* init is only needed for ATAGS based platforms */
 156         if (!IS_ENABLED(CONFIG_ATAGS) ||
 157             (!soc_is_s3c24xx() && !soc_is_s3c64xx()))
 158                 return 0;
 159
 160         // do the correct init for cpu
 161
 162         if (cpu == NULL) {
 163                 /* Not needed when booting with device tree. */
 164                 if (of_have_populated_dt())
 165                         return 0;
 166                 panic("s3c_arch_init: NULL cpu\n");
 167         }
 168
 169         ret = (cpu->init)();
 170         if (ret != 0)
 171                 return ret;
 172 #if IS_ENABLED(CONFIG_SAMSUNG_ATAGS)
 173         ret = platform_add_devices(s3c24xx_uart_devs, nr_uarts);
 174 #endif
 175         return ret;
 176 }
 177
 178 arch_initcall(s3c_arch_init);