root/arch/arm/plat-samsung/init.c

DEFINITIONS

1. s3c_lookup_cpu
2. s3c_init_cpu
3. s3c24xx_init_clocks
4. s3c24xx_init_uartdevs
5. s3c24xx_init_uarts
6. s3c_arch_init

   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 <plat/cpu.h>
  27 #include <plat/devs.h>
  28 
  29 static struct cpu_table *cpu;
  30 
  31 static 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 
  43 void __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 
  73 void __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)
  89 static int nr_uarts __initdata = 0;
  90 
  91 #ifdef CONFIG_SERIAL_SAMSUNG_UARTS
  92 static 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 
 104 void __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 
 134 void __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 
 146 static 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 
 173 arch_initcall(s3c_arch_init);