xref: /openbmc/u-boot/arch/nios2/lib/bootm.c (revision e9c847c3)
1 /*
2  * (C) Copyright 2003, Psyent Corporation <www.psyent.com>
3  * Scott McNutt <smcnutt@psyent.com>
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 #include <common.h>
9 
10 #define NIOS_MAGIC 0x534f494e /* enable command line and initrd passing */
11 
12 int do_bootm_linux(int flag, int argc, char * const argv[], bootm_headers_t *images)
13 {
14 	void (*kernel)(int, int, int, char *) = (void *)images->ep;
15 	char *commandline = getenv("bootargs");
16 	ulong initrd_start = images->rd_start;
17 	ulong initrd_end = images->rd_end;
18 	char *of_flat_tree = NULL;
19 #if defined(CONFIG_OF_LIBFDT)
20 	/* did generic code already find a device tree? */
21 	if (images->ft_len)
22 		of_flat_tree = images->ft_addr;
23 #endif
24 	if (!of_flat_tree && argc > 1)
25 		of_flat_tree = (char *)simple_strtoul(argv[1], NULL, 16);
26 	if (of_flat_tree)
27 		initrd_end = (ulong)of_flat_tree;
28 
29 	/*
30 	 * allow the PREP bootm subcommand, it is required for bootm to work
31 	 */
32 	if (flag & BOOTM_STATE_OS_PREP)
33 		return 0;
34 
35 	if ((flag != 0) && (flag != BOOTM_STATE_OS_GO))
36 		return 1;
37 
38 	/* flushes data and instruction caches before calling the kernel */
39 	disable_interrupts();
40 	flush_dcache_all();
41 
42 	debug("bootargs=%s @ 0x%lx\n", commandline, (ulong)&commandline);
43 	debug("initrd=0x%lx-0x%lx\n", (ulong)initrd_start, (ulong)initrd_end);
44 	/* kernel parameters passing
45 	 * r4 : NIOS magic
46 	 * r5 : initrd start
47 	 * r6 : initrd end or fdt
48 	 * r7 : kernel command line
49 	 * fdt is passed to kernel via r6, the same as initrd_end. fdt will be
50 	 * verified with fdt magic. when both initrd and fdt are used at the
51 	 * same time, fdt must follow immediately after initrd.
52 	 */
53 	kernel(NIOS_MAGIC, initrd_start, initrd_end, commandline);
54 	/* does not return */
55 
56 	return 1;
57 }
58