LXR linux/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
  34static struct cpu_table *cpu;
  35
  36static 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
  48void __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
  78void __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)
  94static int nr_uarts __initdata = 0;
  95
  96#ifdef CONFIG_SERIAL_SAMSUNG_UARTS
  97static 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
 109void __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
 139void __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
 151static 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
 178arch_initcall(s3c_arch_init);
 179