xref: /openbmc/u-boot/arch/arc/lib/bootm.c (revision 752a0b08)
1 /*
2  * Copyright (C) 2013-2014 Synopsys, Inc. All rights reserved.
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 #include <common.h>
8 
9 DECLARE_GLOBAL_DATA_PTR;
10 
11 static ulong get_sp(void)
12 {
13 	ulong ret;
14 
15 	asm("mov %0, sp" : "=r"(ret) : );
16 	return ret;
17 }
18 
19 void arch_lmb_reserve(struct lmb *lmb)
20 {
21 	ulong sp;
22 
23 	/*
24 	 * Booting a (Linux) kernel image
25 	 *
26 	 * Allocate space for command line and board info - the
27 	 * address should be as high as possible within the reach of
28 	 * the kernel (see CONFIG_SYS_BOOTMAPSZ settings), but in unused
29 	 * memory, which means far enough below the current stack
30 	 * pointer.
31 	 */
32 	sp = get_sp();
33 	debug("## Current stack ends at 0x%08lx ", sp);
34 
35 	/* adjust sp by 4K to be safe */
36 	sp -= 4096;
37 	lmb_reserve(lmb, sp, (CONFIG_SYS_SDRAM_BASE + gd->ram_size - sp));
38 }
39 
40 static int cleanup_before_linux(void)
41 {
42 	disable_interrupts();
43 	flush_dcache_all();
44 	invalidate_icache_all();
45 
46 	return 0;
47 }
48 
49 /* Subcommand: PREP */
50 static void boot_prep_linux(bootm_headers_t *images)
51 {
52 	if (image_setup_linux(images))
53 		hang();
54 }
55 
56 /* Subcommand: GO */
57 static void boot_jump_linux(bootm_headers_t *images, int flag)
58 {
59 	void (*kernel_entry)(int zero, int arch, uint params);
60 	unsigned int r0, r2;
61 	int fake = (flag & BOOTM_STATE_OS_FAKE_GO);
62 
63 	kernel_entry = (void (*)(int, int, uint))images->ep;
64 
65 	debug("## Transferring control to Linux (at address %08lx)...\n",
66 	      (ulong) kernel_entry);
67 	bootstage_mark(BOOTSTAGE_ID_RUN_OS);
68 
69 	printf("\nStarting kernel ...%s\n\n", fake ?
70 	       "(fake run for tracing)" : "");
71 	bootstage_mark_name(BOOTSTAGE_ID_BOOTM_HANDOFF, "start_kernel");
72 
73 	cleanup_before_linux();
74 
75 	if (IMAGE_ENABLE_OF_LIBFDT && images->ft_len) {
76 		r0 = 2;
77 		r2 = (unsigned int)images->ft_addr;
78 	} else {
79 		r0 = 1;
80 		r2 = (unsigned int)getenv("bootargs");
81 	}
82 
83 	if (!fake)
84 		kernel_entry(r0, 0, r2);
85 }
86 
87 int do_bootm_linux(int flag, int argc, char *argv[], bootm_headers_t *images)
88 {
89 	/* No need for those on ARC */
90 	if ((flag & BOOTM_STATE_OS_BD_T) || (flag & BOOTM_STATE_OS_CMDLINE))
91 		return -1;
92 
93 	if (flag & BOOTM_STATE_OS_PREP) {
94 		boot_prep_linux(images);
95 		return 0;
96 	}
97 
98 	if (flag & (BOOTM_STATE_OS_GO | BOOTM_STATE_OS_FAKE_GO)) {
99 		boot_jump_linux(images, flag);
100 		return 0;
101 	}
102 
103 	boot_prep_linux(images);
104 	boot_jump_linux(images, flag);
105 	return 0;
106 }
107