1 /*
2  *  Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
3  *  JZ4740 SoC prom code
4  *
5  *  This program is free software; you can redistribute it and/or modify it
6  *  under  the terms of the GNU General  Public License as published by the
7  *  Free Software Foundation;  either version 2 of the License, or (at your
8  *  option) any later version.
9  *
10  *  You should have received a copy of the GNU General Public License along
11  *  with this program; if not, write to the Free Software Foundation, Inc.,
12  *  675 Mass Ave, Cambridge, MA 02139, USA.
13  *
14  */
15 
16 #include <linux/module.h>
17 #include <linux/kernel.h>
18 #include <linux/init.h>
19 #include <linux/string.h>
20 
21 #include <linux/serial_reg.h>
22 
23 #include <asm/bootinfo.h>
24 #include <asm/mach-jz4740/base.h>
25 
jz4740_init_cmdline(int argc,char * argv[])26 static __init void jz4740_init_cmdline(int argc, char *argv[])
27 {
28 	unsigned int count = COMMAND_LINE_SIZE - 1;
29 	int i;
30 	char *dst = &(arcs_cmdline[0]);
31 	char *src;
32 
33 	for (i = 1; i < argc && count; ++i) {
34 		src = argv[i];
35 		while (*src && count) {
36 			*dst++ = *src++;
37 			--count;
38 		}
39 		*dst++ = ' ';
40 	}
41 	if (i > 1)
42 		--dst;
43 
44 	*dst = 0;
45 }
46 
prom_init(void)47 void __init prom_init(void)
48 {
49 	jz4740_init_cmdline((int)fw_arg0, (char **)fw_arg1);
50 	mips_machtype = MACH_INGENIC_JZ4740;
51 }
52 
prom_free_prom_memory(void)53 void __init prom_free_prom_memory(void)
54 {
55 }
56 
57 #define UART_REG(_reg) ((void __iomem *)CKSEG1ADDR(JZ4740_UART0_BASE_ADDR + (_reg << 2)))
58 
prom_putchar(char c)59 void prom_putchar(char c)
60 {
61 	uint8_t lsr;
62 
63 	do {
64 		lsr = readb(UART_REG(UART_LSR));
65 	} while ((lsr & UART_LSR_TEMT) == 0);
66 
67 	writeb(c, UART_REG(UART_TX));
68 }
69