linux/arch/arm/mach-s3c/init.c
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   1// SPDX-License-Identifier: GPL-2.0
   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/*
  10 * NOTE: Code in this file is not used on S3C64xx when booting with
  11 * Device Tree support.
  12 */
  13
  14#include <linux/init.h>
  15#include <linux/module.h>
  16#include <linux/interrupt.h>
  17#include <linux/ioport.h>
  18#include <linux/serial_core.h>
  19#include <linux/serial_s3c.h>
  20#include <linux/platform_device.h>
  21#include <linux/of.h>
  22
  23#include <asm/mach/arch.h>
  24#include <asm/mach/map.h>
  25
  26#include "cpu.h"
  27#include "devs.h"
  28
  29static struct cpu_table *cpu;
  30
  31static struct cpu_table * __init s3c_lookup_cpu(unsigned long idcode,
  32                                                struct cpu_table *tab,
  33                                                unsigned int count)
  34{
  35        for (; count != 0; count--, tab++) {
  36                if ((idcode & tab->idmask) == (tab->idcode & tab->idmask))
  37                        return tab;
  38        }
  39
  40        return NULL;
  41}
  42
  43void __init s3c_init_cpu(unsigned long idcode,
  44                         struct cpu_table *cputab, unsigned int cputab_size)
  45{
  46        cpu = s3c_lookup_cpu(idcode, cputab, cputab_size);
  47
  48        if (cpu == NULL) {
  49                printk(KERN_ERR "Unknown CPU type 0x%08lx\n", idcode);
  50                panic("Unknown S3C24XX CPU");
  51        }
  52
  53        printk("CPU %s (id 0x%08lx)\n", cpu->name, idcode);
  54
  55        if (cpu->init == NULL) {
  56                printk(KERN_ERR "CPU %s support not enabled\n", cpu->name);
  57                panic("Unsupported Samsung CPU");
  58        }
  59
  60        if (cpu->map_io)
  61                cpu->map_io();
  62}
  63
  64/* s3c24xx_init_clocks
  65 *
  66 * Initialise the clock subsystem and associated information from the
  67 * given master crystal value.
  68 *
  69 * xtal  = 0 -> use default PLL crystal value (normally 12MHz)
  70 *      != 0 -> PLL crystal value in Hz
  71*/
  72
  73void __init s3c24xx_init_clocks(int xtal)
  74{
  75        if (xtal == 0)
  76                xtal = 12*1000*1000;
  77
  78        if (cpu == NULL)
  79                panic("s3c24xx_init_clocks: no cpu setup?\n");
  80
  81        if (cpu->init_clocks == NULL)
  82                panic("s3c24xx_init_clocks: cpu has no clock init\n");
  83        else
  84                (cpu->init_clocks)(xtal);
  85}
  86
  87/* uart management */
  88#if IS_ENABLED(CONFIG_SAMSUNG_ATAGS)
  89static int nr_uarts __initdata = 0;
  90
  91#ifdef CONFIG_SERIAL_SAMSUNG_UARTS
  92static struct s3c2410_uartcfg uart_cfgs[CONFIG_SERIAL_SAMSUNG_UARTS];
  93#endif
  94
  95/* s3c24xx_init_uartdevs
  96 *
  97 * copy the specified platform data and configuration into our central
  98 * set of devices, before the data is thrown away after the init process.
  99 *
 100 * This also fills in the array passed to the serial driver for the
 101 * early initialisation of the console.
 102*/
 103
 104void __init s3c24xx_init_uartdevs(char *name,
 105                                  struct s3c24xx_uart_resources *res,
 106                                  struct s3c2410_uartcfg *cfg, int no)
 107{
 108#ifdef CONFIG_SERIAL_SAMSUNG_UARTS
 109        struct platform_device *platdev;
 110        struct s3c2410_uartcfg *cfgptr = uart_cfgs;
 111        struct s3c24xx_uart_resources *resp;
 112        int uart;
 113
 114        memcpy(cfgptr, cfg, sizeof(struct s3c2410_uartcfg) * no);
 115
 116        for (uart = 0; uart < no; uart++, cfg++, cfgptr++) {
 117                platdev = s3c24xx_uart_src[cfgptr->hwport];
 118
 119                resp = res + cfgptr->hwport;
 120
 121                s3c24xx_uart_devs[uart] = platdev;
 122
 123                platdev->name = name;
 124                platdev->resource = resp->resources;
 125                platdev->num_resources = resp->nr_resources;
 126
 127                platdev->dev.platform_data = cfgptr;
 128        }
 129
 130        nr_uarts = no;
 131#endif
 132}
 133
 134void __init s3c24xx_init_uarts(struct s3c2410_uartcfg *cfg, int no)
 135{
 136        if (cpu == NULL)
 137                return;
 138
 139        if (cpu->init_uarts == NULL && IS_ENABLED(CONFIG_SAMSUNG_ATAGS)) {
 140                printk(KERN_ERR "s3c24xx_init_uarts: cpu has no uart init\n");
 141        } else
 142                (cpu->init_uarts)(cfg, no);
 143}
 144#endif
 145
 146static int __init s3c_arch_init(void)
 147{
 148        int ret;
 149
 150        /* init is only needed for ATAGS based platforms */
 151        if (!IS_ENABLED(CONFIG_ATAGS) ||
 152            (!soc_is_s3c24xx() && !soc_is_s3c64xx()))
 153                return 0;
 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
 173arch_initcall(s3c_arch_init);
 174