xref: /openbmc/u-boot/arch/m68k/lib/bootm.c (revision 88dc4099)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2003
4  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5  */
6 
7 #include <common.h>
8 #include <command.h>
9 #include <image.h>
10 #include <u-boot/zlib.h>
11 #include <bzlib.h>
12 #include <watchdog.h>
13 #include <environment.h>
14 #include <asm/byteorder.h>
15 #ifdef CONFIG_SHOW_BOOT_PROGRESS
16 # include <status_led.h>
17 #endif
18 
19 DECLARE_GLOBAL_DATA_PTR;
20 
21 #define PHYSADDR(x) x
22 
23 #define LINUX_MAX_ENVS		256
24 #define LINUX_MAX_ARGS		256
25 
26 static ulong get_sp (void);
27 static void set_clocks_in_mhz (bd_t *kbd);
28 
29 void arch_lmb_reserve(struct lmb *lmb)
30 {
31 	ulong sp;
32 
33 	/*
34 	 * Booting a (Linux) kernel image
35 	 *
36 	 * Allocate space for command line and board info - the
37 	 * address should be as high as possible within the reach of
38 	 * the kernel (see CONFIG_SYS_BOOTMAPSZ settings), but in unused
39 	 * memory, which means far enough below the current stack
40 	 * pointer.
41 	 */
42 	sp = get_sp();
43 	debug ("## Current stack ends at 0x%08lx ", sp);
44 
45 	/* adjust sp by 1K to be safe */
46 	sp -= 1024;
47 	lmb_reserve(lmb, sp, (CONFIG_SYS_SDRAM_BASE + gd->ram_size - sp));
48 }
49 
50 int do_bootm_linux(int flag, int argc, char * const argv[], bootm_headers_t *images)
51 {
52 	int ret;
53 	bd_t  *kbd;
54 	void  (*kernel) (bd_t *, ulong, ulong, ulong, ulong);
55 	struct lmb *lmb = &images->lmb;
56 
57 	/*
58 	 * allow the PREP bootm subcommand, it is required for bootm to work
59 	 */
60 	if (flag & BOOTM_STATE_OS_PREP)
61 		return 0;
62 
63 	if ((flag != 0) && (flag != BOOTM_STATE_OS_GO))
64 		return 1;
65 
66 	/* allocate space for kernel copy of board info */
67 	ret = boot_get_kbd (lmb, &kbd);
68 	if (ret) {
69 		puts("ERROR with allocation of kernel bd\n");
70 		goto error;
71 	}
72 	set_clocks_in_mhz(kbd);
73 
74 	ret = image_setup_linux(images);
75 	if (ret)
76 		goto error;
77 
78 	kernel = (void (*)(bd_t *, ulong, ulong, ulong, ulong))images->ep;
79 
80 	debug("## Transferring control to Linux (at address %08lx) ...\n",
81 	      (ulong) kernel);
82 
83 	bootstage_mark(BOOTSTAGE_ID_RUN_OS);
84 
85 	/*
86 	 * Linux Kernel Parameters (passing board info data):
87 	 *   sp+00: Ignore, side effect of using jsr to jump to kernel
88 	 *   sp+04: ptr to board info data
89 	 *   sp+08: initrd_start or 0 if no initrd
90 	 *   sp+12: initrd_end - unused if initrd_start is 0
91 	 *   sp+16: Start of command line string
92 	 *   sp+20: End   of command line string
93 	 */
94 	(*kernel)(kbd, images->initrd_start, images->initrd_end,
95 		  images->cmdline_start, images->cmdline_end);
96 	/* does not return */
97 error:
98 	return 1;
99 }
100 
101 static ulong get_sp (void)
102 {
103 	ulong sp;
104 
105 	asm("movel %%a7, %%d0\n"
106 	    "movel %%d0, %0\n": "=d"(sp): :"%d0");
107 
108 	return sp;
109 }
110 
111 static void set_clocks_in_mhz (bd_t *kbd)
112 {
113 	char *s;
114 
115 	s = env_get("clocks_in_mhz");
116 	if (s) {
117 		/* convert all clock information to MHz */
118 		kbd->bi_intfreq /= 1000000L;
119 		kbd->bi_busfreq /= 1000000L;
120 	}
121 }
122