xref: /openbmc/u-boot/arch/arc/lib/bootm.c (revision 78a88f79)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2013-2014 Synopsys, Inc. All rights reserved.
4  */
5 
6 #include <asm/cache.h>
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 	sync_n_cleanup_cache_all();
44 
45 	return 0;
46 }
47 
48 __weak int board_prep_linux(bootm_headers_t *images) { return 0; }
49 
50 /* Subcommand: PREP */
51 static int boot_prep_linux(bootm_headers_t *images)
52 {
53 	int ret;
54 
55 	ret = image_setup_linux(images);
56 	if (ret)
57 		return ret;
58 
59 	return board_prep_linux(images);
60 }
61 
62 /* Generic implementation for single core CPU */
63 __weak void board_jump_and_run(ulong entry, int zero, int arch, uint params)
64 {
65 	void (*kernel_entry)(int zero, int arch, uint params);
66 
67 	kernel_entry = (void (*)(int, int, uint))entry;
68 
69 	kernel_entry(zero, arch, params);
70 }
71 
72 /* Subcommand: GO */
73 static void boot_jump_linux(bootm_headers_t *images, int flag)
74 {
75 	ulong kernel_entry;
76 	unsigned int r0, r2;
77 	int fake = (flag & BOOTM_STATE_OS_FAKE_GO);
78 
79 	kernel_entry = images->ep;
80 
81 	debug("## Transferring control to Linux (at address %08lx)...\n",
82 	      kernel_entry);
83 	bootstage_mark(BOOTSTAGE_ID_RUN_OS);
84 
85 	printf("\nStarting kernel ...%s\n\n", fake ?
86 	       "(fake run for tracing)" : "");
87 	bootstage_mark_name(BOOTSTAGE_ID_BOOTM_HANDOFF, "start_kernel");
88 
89 	if (IMAGE_ENABLE_OF_LIBFDT && images->ft_len) {
90 		r0 = 2;
91 		r2 = (unsigned int)images->ft_addr;
92 	} else {
93 		r0 = 1;
94 		r2 = (unsigned int)env_get("bootargs");
95 	}
96 
97 	cleanup_before_linux();
98 
99 	if (!fake)
100 		board_jump_and_run(kernel_entry, r0, 0, r2);
101 }
102 
103 int do_bootm_linux(int flag, int argc, char *argv[], bootm_headers_t *images)
104 {
105 	/* No need for those on ARC */
106 	if ((flag & BOOTM_STATE_OS_BD_T) || (flag & BOOTM_STATE_OS_CMDLINE))
107 		return -1;
108 
109 	if (flag & BOOTM_STATE_OS_PREP)
110 		return boot_prep_linux(images);
111 
112 	if (flag & (BOOTM_STATE_OS_GO | BOOTM_STATE_OS_FAKE_GO)) {
113 		boot_jump_linux(images, flag);
114 		return 0;
115 	}
116 
117 	return -1;
118 }
119