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 #include <plat/clock.h>
  34
  35 static struct cpu_table *cpu;
  36
  37 static struct cpu_table * __init s3c_lookup_cpu(unsigned long idcode,
  38                                                 struct cpu_table *tab,
  39                                                 unsigned int count)
  40 {
  41         for (; count != 0; count--, tab++) {
  42                 if ((idcode & tab->idmask) == (tab->idcode & tab->idmask))
  43                         return tab;
  44         }
  45
  46         return NULL;
  47 }
  48
  49 void __init s3c_init_cpu(unsigned long idcode,
  50                          struct cpu_table *cputab, unsigned int cputab_size)
  51 {
  52         cpu = s3c_lookup_cpu(idcode, cputab, cputab_size);
  53
  54         if (cpu == NULL) {
  55                 printk(KERN_ERR "Unknown CPU type 0x%08lx\n", idcode);
  56                 panic("Unknown S3C24XX CPU");
  57         }
  58
  59         printk("CPU %s (id 0x%08lx)\n", cpu->name, idcode);
  60
  61         if (cpu->init == NULL) {
  62                 printk(KERN_ERR "CPU %s support not enabled\n", cpu->name);
  63                 panic("Unsupported Samsung CPU");
  64         }
  65
  66         if (cpu->map_io)
  67                 cpu->map_io();
  68 }
  69
  70 /* s3c24xx_init_clocks
  71  *
  72  * Initialise the clock subsystem and associated information from the
  73  * given master crystal value.
  74  *
  75  * xtal  = 0 -> use default PLL crystal value (normally 12MHz)
  76  *      != 0 -> PLL crystal value in Hz
  77 */
  78
  79 void __init s3c24xx_init_clocks(int xtal)
  80 {
  81         if (xtal == 0)
  82                 xtal = 12*1000*1000;
  83
  84         if (cpu == NULL)
  85                 panic("s3c24xx_init_clocks: no cpu setup?\n");
  86
  87         if (cpu->init_clocks == NULL)
  88                 panic("s3c24xx_init_clocks: cpu has no clock init\n");
  89         else
  90                 (cpu->init_clocks)(xtal);
  91 }
  92
  93 /* uart management */
  94 #if IS_ENABLED(CONFIG_SAMSUNG_ATAGS)
  95 static int nr_uarts __initdata = 0;
  96
  97 #ifdef CONFIG_SERIAL_SAMSUNG_UARTS
  98 static struct s3c2410_uartcfg uart_cfgs[CONFIG_SERIAL_SAMSUNG_UARTS];
  99 #endif
 100
 101 /* s3c24xx_init_uartdevs
 102  *
 103  * copy the specified platform data and configuration into our central
 104  * set of devices, before the data is thrown away after the init process.
 105  *
 106  * This also fills in the array passed to the serial driver for the
 107  * early initialisation of the console.
 108 */
 109
 110 void __init s3c24xx_init_uartdevs(char *name,
 111                                   struct s3c24xx_uart_resources *res,
 112                                   struct s3c2410_uartcfg *cfg, int no)
 113 {
 114 #ifdef CONFIG_SERIAL_SAMSUNG_UARTS
 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 #endif
 138 }
 139
 140 void __init s3c24xx_init_uarts(struct s3c2410_uartcfg *cfg, int no)
 141 {
 142         if (cpu == NULL)
 143                 return;
 144
 145         if (cpu->init_uarts == NULL && IS_ENABLED(CONFIG_SAMSUNG_ATAGS)) {
 146                 printk(KERN_ERR "s3c24xx_init_uarts: cpu has no uart init\n");
 147         } else
 148                 (cpu->init_uarts)(cfg, no);
 149 }
 150 #endif
 151
 152 static int __init s3c_arch_init(void)
 153 {
 154         int ret;
 155
 156         // do the correct init for cpu
 157
 158         if (cpu == NULL) {
 159                 /* Not needed when booting with device tree. */
 160                 if (of_have_populated_dt())
 161                         return 0;
 162                 panic("s3c_arch_init: NULL cpu\n");
 163         }
 164
 165         ret = (cpu->init)();
 166         if (ret != 0)
 167                 return ret;
 168 #if IS_ENABLED(CONFIG_SAMSUNG_ATAGS)
 169         ret = platform_add_devices(s3c24xx_uart_devs, nr_uarts);
 170 #endif
 171         return ret;
 172 }
 173
 174 arch_initcall(s3c_arch_init);