xref: /openbmc/linux/arch/microblaze/kernel/setup.c (revision 7dd65feb)
1 /*
2  * Copyright (C) 2007-2009 Michal Simek <monstr@monstr.eu>
3  * Copyright (C) 2007-2009 PetaLogix
4  * Copyright (C) 2006 Atmark Techno, Inc.
5  *
6  * This file is subject to the terms and conditions of the GNU General Public
7  * License. See the file "COPYING" in the main directory of this archive
8  * for more details.
9  */
10 
11 #include <linux/init.h>
12 #include <linux/string.h>
13 #include <linux/seq_file.h>
14 #include <linux/cpu.h>
15 #include <linux/initrd.h>
16 #include <linux/console.h>
17 #include <linux/debugfs.h>
18 
19 #include <asm/setup.h>
20 #include <asm/sections.h>
21 #include <asm/page.h>
22 #include <linux/io.h>
23 #include <linux/bug.h>
24 #include <linux/param.h>
25 #include <linux/cache.h>
26 #include <asm/cacheflush.h>
27 #include <asm/entry.h>
28 #include <asm/cpuinfo.h>
29 
30 #include <asm/system.h>
31 #include <asm/prom.h>
32 #include <asm/pgtable.h>
33 
34 DEFINE_PER_CPU(unsigned int, KSP);	/* Saved kernel stack pointer */
35 DEFINE_PER_CPU(unsigned int, KM);	/* Kernel/user mode */
36 DEFINE_PER_CPU(unsigned int, ENTRY_SP);	/* Saved SP on kernel entry */
37 DEFINE_PER_CPU(unsigned int, R11_SAVE);	/* Temp variable for entry */
38 DEFINE_PER_CPU(unsigned int, CURRENT_SAVE);	/* Saved current pointer */
39 
40 unsigned int boot_cpuid;
41 char cmd_line[COMMAND_LINE_SIZE];
42 
43 void __init setup_arch(char **cmdline_p)
44 {
45 	*cmdline_p = cmd_line;
46 
47 	console_verbose();
48 
49 	unflatten_device_tree();
50 
51 	/* NOTE I think that this function is not necessary to call */
52 	/* irq_early_init(); */
53 	setup_cpuinfo();
54 
55 	microblaze_cache_init();
56 
57 	enable_dcache();
58 
59 	invalidate_icache();
60 	enable_icache();
61 
62 	setup_memory();
63 
64 #if defined(CONFIG_SELFMOD_INTC) || defined(CONFIG_SELFMOD_TIMER)
65 	printk(KERN_NOTICE "Self modified code enable\n");
66 #endif
67 
68 #ifdef CONFIG_VT
69 #if defined(CONFIG_XILINX_CONSOLE)
70 	conswitchp = &xil_con;
71 #elif defined(CONFIG_DUMMY_CONSOLE)
72 	conswitchp = &dummy_con;
73 #endif
74 #endif
75 }
76 
77 #ifdef CONFIG_MTD_UCLINUX
78 /* Handle both romfs and cramfs types, without generating unnecessary
79  code (ie no point checking for CRAMFS if it's not even enabled) */
80 inline unsigned get_romfs_len(unsigned *addr)
81 {
82 #ifdef CONFIG_ROMFS_FS
83 	if (memcmp(&addr[0], "-rom1fs-", 8) == 0) /* romfs */
84 		return be32_to_cpu(addr[2]);
85 #endif
86 
87 #ifdef CONFIG_CRAMFS
88 	if (addr[0] == le32_to_cpu(0x28cd3d45)) /* cramfs */
89 		return le32_to_cpu(addr[1]);
90 #endif
91 	return 0;
92 }
93 #endif	/* CONFIG_MTD_UCLINUX_EBSS */
94 
95 void __init machine_early_init(const char *cmdline, unsigned int ram,
96 		unsigned int fdt, unsigned int msr)
97 {
98 	unsigned long *src, *dst = (unsigned long *)0x0;
99 
100 	/* If CONFIG_MTD_UCLINUX is defined, assume ROMFS is at the
101 	 * end of kernel. There are two position which we want to check.
102 	 * The first is __init_end and the second __bss_start.
103 	 */
104 #ifdef CONFIG_MTD_UCLINUX
105 	int romfs_size;
106 	unsigned int romfs_base;
107 	char *old_klimit = klimit;
108 
109 	romfs_base = (ram ? ram : (unsigned int)&__init_end);
110 	romfs_size = PAGE_ALIGN(get_romfs_len((unsigned *)romfs_base));
111 	if (!romfs_size) {
112 		romfs_base = (unsigned int)&__bss_start;
113 		romfs_size = PAGE_ALIGN(get_romfs_len((unsigned *)romfs_base));
114 	}
115 
116 	/* Move ROMFS out of BSS before clearing it */
117 	if (romfs_size > 0) {
118 		memmove(&_ebss, (int *)romfs_base, romfs_size);
119 		klimit += romfs_size;
120 	}
121 #endif
122 
123 /* clearing bss section */
124 	memset(__bss_start, 0, __bss_stop-__bss_start);
125 	memset(_ssbss, 0, _esbss-_ssbss);
126 
127 	/* Copy command line passed from bootloader */
128 #ifndef CONFIG_CMDLINE_BOOL
129 	if (cmdline && cmdline[0] != '\0')
130 		strlcpy(cmd_line, cmdline, COMMAND_LINE_SIZE);
131 #endif
132 
133 	lockdep_init();
134 
135 /* initialize device tree for usage in early_printk */
136 	early_init_devtree((void *)_fdt_start);
137 
138 #ifdef CONFIG_EARLY_PRINTK
139 	setup_early_printk(NULL);
140 #endif
141 
142 	early_printk("Ramdisk addr 0x%08x, ", ram);
143 	if (fdt)
144 		early_printk("FDT at 0x%08x\n", fdt);
145 	else
146 		early_printk("Compiled-in FDT at 0x%08x\n",
147 					(unsigned int)_fdt_start);
148 
149 #ifdef CONFIG_MTD_UCLINUX
150 	early_printk("Found romfs @ 0x%08x (0x%08x)\n",
151 			romfs_base, romfs_size);
152 	early_printk("#### klimit %p ####\n", old_klimit);
153 	BUG_ON(romfs_size < 0); /* What else can we do? */
154 
155 	early_printk("Moved 0x%08x bytes from 0x%08x to 0x%08x\n",
156 			romfs_size, romfs_base, (unsigned)&_ebss);
157 
158 	early_printk("New klimit: 0x%08x\n", (unsigned)klimit);
159 #endif
160 
161 #if CONFIG_XILINX_MICROBLAZE0_USE_MSR_INSTR
162 	if (msr)
163 		early_printk("!!!Your kernel has setup MSR instruction but "
164 				"CPU don't have it %d\n", msr);
165 #else
166 	if (!msr)
167 		early_printk("!!!Your kernel not setup MSR instruction but "
168 				"CPU have it %d\n", msr);
169 #endif
170 
171 	for (src = __ivt_start; src < __ivt_end; src++, dst++)
172 		*dst = *src;
173 
174 	/* Initialize global data */
175 	per_cpu(KM, 0) = 0x1;	/* We start in kernel mode */
176 	per_cpu(CURRENT_SAVE, 0) = (unsigned long)current;
177 }
178 
179 #ifdef CONFIG_DEBUG_FS
180 struct dentry *of_debugfs_root;
181 
182 static int microblaze_debugfs_init(void)
183 {
184 	of_debugfs_root = debugfs_create_dir("microblaze", NULL);
185 
186 	return of_debugfs_root == NULL;
187 }
188 arch_initcall(microblaze_debugfs_init);
189 #endif
190