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
29 static struct cpu_table *cpu;
30
s3c_lookup_cpu(unsigned long idcode,struct cpu_table * tab,unsigned int count)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
s3c_init_cpu(unsigned long idcode,struct cpu_table * cputab,unsigned int cputab_size)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
s3c24xx_init_clocks(int xtal)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
s3c24xx_init_uartdevs(char * name,struct s3c24xx_uart_resources * res,struct s3c2410_uartcfg * cfg,int no)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
s3c24xx_init_uarts(struct s3c2410_uartcfg * cfg,int no)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
s3c_arch_init(void)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);
174