xref: /openbmc/u-boot/arch/arc/lib/bootm.c (revision fdef3895)
1 /*
2  * Copyright (C) 2013-2014 Synopsys, Inc. All rights reserved.
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 #include <asm/cache.h>
8 #include <common.h>
9 
10 DECLARE_GLOBAL_DATA_PTR;
11 
12 static ulong get_sp(void)
13 {
14 	ulong ret;
15 
16 	asm("mov %0, sp" : "=r"(ret) : );
17 	return ret;
18 }
19 
20 void arch_lmb_reserve(struct lmb *lmb)
21 {
22 	ulong sp;
23 
24 	/*
25 	 * Booting a (Linux) kernel image
26 	 *
27 	 * Allocate space for command line and board info - the
28 	 * address should be as high as possible within the reach of
29 	 * the kernel (see CONFIG_SYS_BOOTMAPSZ settings), but in unused
30 	 * memory, which means far enough below the current stack
31 	 * pointer.
32 	 */
33 	sp = get_sp();
34 	debug("## Current stack ends at 0x%08lx ", sp);
35 
36 	/* adjust sp by 4K to be safe */
37 	sp -= 4096;
38 	lmb_reserve(lmb, sp, (CONFIG_SYS_SDRAM_BASE + gd->ram_size - sp));
39 }
40 
41 static int cleanup_before_linux(void)
42 {
43 	disable_interrupts();
44 	sync_n_cleanup_cache_all();
45 
46 	return 0;
47 }
48 
49 __weak int board_prep_linux(bootm_headers_t *images) { return 0; }
50 
51 /* Subcommand: PREP */
52 static int boot_prep_linux(bootm_headers_t *images)
53 {
54 	int ret;
55 
56 	ret = image_setup_linux(images);
57 	if (ret)
58 		return ret;
59 
60 	return board_prep_linux(images);
61 }
62 
63 /* Generic implementation for single core CPU */
64 __weak void board_jump_and_run(ulong entry, int zero, int arch, uint params)
65 {
66 	void (*kernel_entry)(int zero, int arch, uint params);
67 
68 	kernel_entry = (void (*)(int, int, uint))entry;
69 
70 	kernel_entry(zero, arch, params);
71 }
72 
73 /* Subcommand: GO */
74 static void boot_jump_linux(bootm_headers_t *images, int flag)
75 {
76 	ulong kernel_entry;
77 	unsigned int r0, r2;
78 	int fake = (flag & BOOTM_STATE_OS_FAKE_GO);
79 
80 	kernel_entry = images->ep;
81 
82 	debug("## Transferring control to Linux (at address %08lx)...\n",
83 	      kernel_entry);
84 	bootstage_mark(BOOTSTAGE_ID_RUN_OS);
85 
86 	printf("\nStarting kernel ...%s\n\n", fake ?
87 	       "(fake run for tracing)" : "");
88 	bootstage_mark_name(BOOTSTAGE_ID_BOOTM_HANDOFF, "start_kernel");
89 
90 	if (IMAGE_ENABLE_OF_LIBFDT && images->ft_len) {
91 		r0 = 2;
92 		r2 = (unsigned int)images->ft_addr;
93 	} else {
94 		r0 = 1;
95 		r2 = (unsigned int)env_get("bootargs");
96 	}
97 
98 	cleanup_before_linux();
99 
100 	if (!fake)
101 		board_jump_and_run(kernel_entry, r0, 0, r2);
102 }
103 
104 int do_bootm_linux(int flag, int argc, char *argv[], bootm_headers_t *images)
105 {
106 	/* No need for those on ARC */
107 	if ((flag & BOOTM_STATE_OS_BD_T) || (flag & BOOTM_STATE_OS_CMDLINE))
108 		return -1;
109 
110 	if (flag & BOOTM_STATE_OS_PREP)
111 		return boot_prep_linux(images);
112 
113 	if (flag & (BOOTM_STATE_OS_GO | BOOTM_STATE_OS_FAKE_GO)) {
114 		boot_jump_linux(images, flag);
115 		return 0;
116 	}
117 
118 	return -1;
119 }
120