1 /* arch/arm/plat-samsung/include/plat/uncompress.h
2 *
3 * Copyright 2003, 2007 Simtec Electronics
4 * http://armlinux.simtec.co.uk/
5 * Ben Dooks <ben@simtec.co.uk>
6 *
7 * S3C - uncompress code
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
12 */
13
14 #ifndef __ASM_PLAT_UNCOMPRESS_H
15 #define __ASM_PLAT_UNCOMPRESS_H
16
17 typedef unsigned int upf_t; /* cannot include linux/serial_core.h */
18
19 /* uart setup */
20
21 unsigned int fifo_mask;
22 unsigned int fifo_max;
23
24 /* forward declerations */
25
26 static void arch_detect_cpu(void);
27
28 /* defines for UART registers */
29
30 #include <plat/regs-serial.h>
31 #include <plat/regs-watchdog.h>
32
33 /* working in physical space... */
34 #undef S3C2410_WDOGREG
35 #define S3C2410_WDOGREG(x) ((S3C24XX_PA_WATCHDOG + (x)))
36
37 /* how many bytes we allow into the FIFO at a time in FIFO mode */
38 #define FIFO_MAX (14)
39
40 #define uart_base S3C_PA_UART + (S3C_UART_OFFSET * CONFIG_S3C_LOWLEVEL_UART_PORT)
41
42 static __inline__ void
uart_wr(unsigned int reg,unsigned int val)43 uart_wr(unsigned int reg, unsigned int val)
44 {
45 volatile unsigned int *ptr;
46
47 ptr = (volatile unsigned int *)(reg + uart_base);
48 *ptr = val;
49 }
50
51 static __inline__ unsigned int
uart_rd(unsigned int reg)52 uart_rd(unsigned int reg)
53 {
54 volatile unsigned int *ptr;
55
56 ptr = (volatile unsigned int *)(reg + uart_base);
57 return *ptr;
58 }
59
60 /* we can deal with the case the UARTs are being run
61 * in FIFO mode, so that we don't hold up our execution
62 * waiting for tx to happen...
63 */
64
putc(int ch)65 static void putc(int ch)
66 {
67 if (uart_rd(S3C2410_UFCON) & S3C2410_UFCON_FIFOMODE) {
68 int level;
69
70 while (1) {
71 level = uart_rd(S3C2410_UFSTAT);
72 level &= fifo_mask;
73
74 if (level < fifo_max)
75 break;
76 }
77
78 } else {
79 /* not using fifos */
80
81 while ((uart_rd(S3C2410_UTRSTAT) & S3C2410_UTRSTAT_TXE) != S3C2410_UTRSTAT_TXE)
82 barrier();
83 }
84
85 /* write byte to transmission register */
86 uart_wr(S3C2410_UTXH, ch);
87 }
88
flush(void)89 static inline void flush(void)
90 {
91 }
92
93 #define __raw_writel(d, ad) \
94 do { \
95 *((volatile unsigned int __force *)(ad)) = (d); \
96 } while (0)
97
98 /* CONFIG_S3C_BOOT_WATCHDOG
99 *
100 * Simple boot-time watchdog setup, to reboot the system if there is
101 * any problem with the boot process
102 */
103
104 #ifdef CONFIG_S3C_BOOT_WATCHDOG
105
106 #define WDOG_COUNT (0xff00)
107
arch_decomp_wdog(void)108 static inline void arch_decomp_wdog(void)
109 {
110 __raw_writel(WDOG_COUNT, S3C2410_WTCNT);
111 }
112
arch_decomp_wdog_start(void)113 static void arch_decomp_wdog_start(void)
114 {
115 __raw_writel(WDOG_COUNT, S3C2410_WTDAT);
116 __raw_writel(WDOG_COUNT, S3C2410_WTCNT);
117 __raw_writel(S3C2410_WTCON_ENABLE | S3C2410_WTCON_DIV128 | S3C2410_WTCON_RSTEN | S3C2410_WTCON_PRESCALE(0x80), S3C2410_WTCON);
118 }
119
120 #else
121 #define arch_decomp_wdog_start()
122 #define arch_decomp_wdog()
123 #endif
124
125 #ifdef CONFIG_S3C_BOOT_ERROR_RESET
126
arch_decomp_error(const char * x)127 static void arch_decomp_error(const char *x)
128 {
129 putstr("\n\n");
130 putstr(x);
131 putstr("\n\n -- System resetting\n");
132
133 __raw_writel(0x4000, S3C2410_WTDAT);
134 __raw_writel(0x4000, S3C2410_WTCNT);
135 __raw_writel(S3C2410_WTCON_ENABLE | S3C2410_WTCON_DIV128 | S3C2410_WTCON_RSTEN | S3C2410_WTCON_PRESCALE(0x40), S3C2410_WTCON);
136
137 while(1);
138 }
139
140 #define arch_error arch_decomp_error
141 #endif
142
143 #ifdef CONFIG_S3C_BOOT_UART_FORCE_FIFO
arch_enable_uart_fifo(void)144 static inline void arch_enable_uart_fifo(void)
145 {
146 u32 fifocon = uart_rd(S3C2410_UFCON);
147
148 if (!(fifocon & S3C2410_UFCON_FIFOMODE)) {
149 fifocon |= S3C2410_UFCON_RESETBOTH;
150 uart_wr(S3C2410_UFCON, fifocon);
151
152 /* wait for fifo reset to complete */
153 while (1) {
154 fifocon = uart_rd(S3C2410_UFCON);
155 if (!(fifocon & S3C2410_UFCON_RESETBOTH))
156 break;
157 }
158 }
159 }
160 #else
161 #define arch_enable_uart_fifo() do { } while(0)
162 #endif
163
164
165 static void
arch_decomp_setup(void)166 arch_decomp_setup(void)
167 {
168 /* we may need to setup the uart(s) here if we are not running
169 * on an BAST... the BAST will have left the uarts configured
170 * after calling linux.
171 */
172
173 arch_detect_cpu();
174 arch_decomp_wdog_start();
175
176 /* Enable the UART FIFOs if they where not enabled and our
177 * configuration says we should turn them on.
178 */
179
180 arch_enable_uart_fifo();
181 }
182
183
184 #endif /* __ASM_PLAT_UNCOMPRESS_H */
185