linux/linux-5.4.31/arch/arm/plat-samsung/init.c

174 lines
3.9 KiB
C

// SPDX-License-Identifier: GPL-2.0
//
// Copyright (c) 2008 Simtec Electronics
// Ben Dooks <ben@simtec.co.uk>
// http://armlinux.simtec.co.uk/
//
// S3C series CPU initialisation
/*
* NOTE: Code in this file is not used on S3C64xx when booting with
* Device Tree support.
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/serial_core.h>
#include <linux/serial_s3c.h>
#include <linux/platform_device.h>
#include <linux/of.h>
#include <asm/mach/arch.h>
#include <asm/mach/map.h>
#include <plat/cpu.h>
#include <plat/devs.h>
static struct cpu_table *cpu;
static struct cpu_table * __init s3c_lookup_cpu(unsigned long idcode,
struct cpu_table *tab,
unsigned int count)
{
for (; count != 0; count--, tab++) {
if ((idcode & tab->idmask) == (tab->idcode & tab->idmask))
return tab;
}
return NULL;
}
void __init s3c_init_cpu(unsigned long idcode,
struct cpu_table *cputab, unsigned int cputab_size)
{
cpu = s3c_lookup_cpu(idcode, cputab, cputab_size);
if (cpu == NULL) {
printk(KERN_ERR "Unknown CPU type 0x%08lx\n", idcode);
panic("Unknown S3C24XX CPU");
}
printk("CPU %s (id 0x%08lx)\n", cpu->name, idcode);
if (cpu->init == NULL) {
printk(KERN_ERR "CPU %s support not enabled\n", cpu->name);
panic("Unsupported Samsung CPU");
}
if (cpu->map_io)
cpu->map_io();
}
/* s3c24xx_init_clocks
*
* Initialise the clock subsystem and associated information from the
* given master crystal value.
*
* xtal = 0 -> use default PLL crystal value (normally 12MHz)
* != 0 -> PLL crystal value in Hz
*/
void __init s3c24xx_init_clocks(int xtal)
{
if (xtal == 0)
xtal = 12*1000*1000;
if (cpu == NULL)
panic("s3c24xx_init_clocks: no cpu setup?\n");
if (cpu->init_clocks == NULL)
panic("s3c24xx_init_clocks: cpu has no clock init\n");
else
(cpu->init_clocks)(xtal);
}
/* uart management */
#if IS_ENABLED(CONFIG_SAMSUNG_ATAGS)
static int nr_uarts __initdata = 0;
#ifdef CONFIG_SERIAL_SAMSUNG_UARTS
static struct s3c2410_uartcfg uart_cfgs[CONFIG_SERIAL_SAMSUNG_UARTS];
#endif
/* s3c24xx_init_uartdevs
*
* copy the specified platform data and configuration into our central
* set of devices, before the data is thrown away after the init process.
*
* This also fills in the array passed to the serial driver for the
* early initialisation of the console.
*/
void __init s3c24xx_init_uartdevs(char *name,
struct s3c24xx_uart_resources *res,
struct s3c2410_uartcfg *cfg, int no)
{
#ifdef CONFIG_SERIAL_SAMSUNG_UARTS
struct platform_device *platdev;
struct s3c2410_uartcfg *cfgptr = uart_cfgs;
struct s3c24xx_uart_resources *resp;
int uart;
memcpy(cfgptr, cfg, sizeof(struct s3c2410_uartcfg) * no);
for (uart = 0; uart < no; uart++, cfg++, cfgptr++) {
platdev = s3c24xx_uart_src[cfgptr->hwport];
resp = res + cfgptr->hwport;
s3c24xx_uart_devs[uart] = platdev;
platdev->name = name;
platdev->resource = resp->resources;
platdev->num_resources = resp->nr_resources;
platdev->dev.platform_data = cfgptr;
}
nr_uarts = no;
#endif
}
void __init s3c24xx_init_uarts(struct s3c2410_uartcfg *cfg, int no)
{
if (cpu == NULL)
return;
if (cpu->init_uarts == NULL && IS_ENABLED(CONFIG_SAMSUNG_ATAGS)) {
printk(KERN_ERR "s3c24xx_init_uarts: cpu has no uart init\n");
} else
(cpu->init_uarts)(cfg, no);
}
#endif
static int __init s3c_arch_init(void)
{
int ret;
/* init is only needed for ATAGS based platforms */
if (!IS_ENABLED(CONFIG_ATAGS) ||
(!soc_is_s3c24xx() && !soc_is_s3c64xx()))
return 0;
// do the correct init for cpu
if (cpu == NULL) {
/* Not needed when booting with device tree. */
if (of_have_populated_dt())
return 0;
panic("s3c_arch_init: NULL cpu\n");
}
ret = (cpu->init)();
if (ret != 0)
return ret;
#if IS_ENABLED(CONFIG_SAMSUNG_ATAGS)
ret = platform_add_devices(s3c24xx_uart_devs, nr_uarts);
#endif
return ret;
}
arch_initcall(s3c_arch_init);