xref: /kernel/linux/linux-5.10/arch/arm/mach-s3c/init.c (revision 8c2ecf20)
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