xref: /openbmc/linux/arch/microblaze/kernel/setup.c (revision b2765275)
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/clk-provider.h>
13 #include <linux/clocksource.h>
14 #include <linux/string.h>
15 #include <linux/seq_file.h>
16 #include <linux/cpu.h>
17 #include <linux/initrd.h>
18 #include <linux/console.h>
19 #include <linux/debugfs.h>
20 #include <linux/of_fdt.h>
21 
22 #include <asm/setup.h>
23 #include <asm/sections.h>
24 #include <asm/page.h>
25 #include <linux/io.h>
26 #include <linux/bug.h>
27 #include <linux/param.h>
28 #include <linux/pci.h>
29 #include <linux/cache.h>
30 #include <linux/of.h>
31 #include <linux/dma-mapping.h>
32 #include <asm/cacheflush.h>
33 #include <asm/entry.h>
34 #include <asm/cpuinfo.h>
35 
36 #include <asm/pgtable.h>
37 
38 DEFINE_PER_CPU(unsigned int, KSP);	/* Saved kernel stack pointer */
39 DEFINE_PER_CPU(unsigned int, KM);	/* Kernel/user mode */
40 DEFINE_PER_CPU(unsigned int, ENTRY_SP);	/* Saved SP on kernel entry */
41 DEFINE_PER_CPU(unsigned int, R11_SAVE);	/* Temp variable for entry */
42 DEFINE_PER_CPU(unsigned int, CURRENT_SAVE);	/* Saved current pointer */
43 
44 unsigned int boot_cpuid;
45 /*
46  * Placed cmd_line to .data section because can be initialized from
47  * ASM code. Default position is BSS section which is cleared
48  * in machine_early_init().
49  */
50 char cmd_line[COMMAND_LINE_SIZE] __attribute__ ((section(".data")));
51 
52 void __init setup_arch(char **cmdline_p)
53 {
54 	*cmdline_p = boot_command_line;
55 
56 	setup_memory();
57 	parse_early_param();
58 
59 	console_verbose();
60 
61 	unflatten_device_tree();
62 
63 	setup_cpuinfo();
64 
65 	microblaze_cache_init();
66 
67 	xilinx_pci_init();
68 }
69 
70 #ifdef CONFIG_MTD_UCLINUX
71 /* Handle both romfs and cramfs types, without generating unnecessary
72  code (ie no point checking for CRAMFS if it's not even enabled) */
73 inline unsigned get_romfs_len(unsigned *addr)
74 {
75 #ifdef CONFIG_ROMFS_FS
76 	if (memcmp(&addr[0], "-rom1fs-", 8) == 0) /* romfs */
77 		return be32_to_cpu(addr[2]);
78 #endif
79 
80 #ifdef CONFIG_CRAMFS
81 	if (addr[0] == le32_to_cpu(0x28cd3d45)) /* cramfs */
82 		return le32_to_cpu(addr[1]);
83 #endif
84 	return 0;
85 }
86 #endif	/* CONFIG_MTD_UCLINUX_EBSS */
87 
88 unsigned long kernel_tlb;
89 
90 void __init machine_early_init(const char *cmdline, unsigned int ram,
91 		unsigned int fdt, unsigned int msr, unsigned int tlb0,
92 		unsigned int tlb1)
93 {
94 	unsigned long *src, *dst;
95 	unsigned int offset = 0;
96 
97 	/* If CONFIG_MTD_UCLINUX is defined, assume ROMFS is at the
98 	 * end of kernel. There are two position which we want to check.
99 	 * The first is __init_end and the second __bss_start.
100 	 */
101 #ifdef CONFIG_MTD_UCLINUX
102 	int romfs_size;
103 	unsigned int romfs_base;
104 	char *old_klimit = klimit;
105 
106 	romfs_base = (ram ? ram : (unsigned int)&__init_end);
107 	romfs_size = PAGE_ALIGN(get_romfs_len((unsigned *)romfs_base));
108 	if (!romfs_size) {
109 		romfs_base = (unsigned int)&__bss_start;
110 		romfs_size = PAGE_ALIGN(get_romfs_len((unsigned *)romfs_base));
111 	}
112 
113 	/* Move ROMFS out of BSS before clearing it */
114 	if (romfs_size > 0) {
115 		memmove(&__bss_stop, (int *)romfs_base, romfs_size);
116 		klimit += romfs_size;
117 	}
118 #endif
119 
120 /* clearing bss section */
121 	memset(__bss_start, 0, __bss_stop-__bss_start);
122 	memset(_ssbss, 0, _esbss-_ssbss);
123 
124 /* initialize device tree for usage in early_printk */
125 	early_init_devtree(_fdt_start);
126 
127 	/* setup kernel_tlb after BSS cleaning
128 	 * Maybe worth to move to asm code */
129 	kernel_tlb = tlb0 + tlb1;
130 	/* printk("TLB1 0x%08x, TLB0 0x%08x, tlb 0x%x\n", tlb0,
131 							tlb1, kernel_tlb); */
132 
133 	pr_info("Ramdisk addr 0x%08x, ", ram);
134 	if (fdt)
135 		pr_info("FDT at 0x%08x\n", fdt);
136 	else
137 		pr_info("Compiled-in FDT at %p\n", _fdt_start);
138 
139 #ifdef CONFIG_MTD_UCLINUX
140 	pr_info("Found romfs @ 0x%08x (0x%08x)\n",
141 			romfs_base, romfs_size);
142 	pr_info("#### klimit %p ####\n", old_klimit);
143 	BUG_ON(romfs_size < 0); /* What else can we do? */
144 
145 	pr_info("Moved 0x%08x bytes from 0x%08x to 0x%08x\n",
146 			romfs_size, romfs_base, (unsigned)&__bss_stop);
147 
148 	pr_info("New klimit: 0x%08x\n", (unsigned)klimit);
149 #endif
150 
151 #if CONFIG_XILINX_MICROBLAZE0_USE_MSR_INSTR
152 	if (msr) {
153 		pr_info("!!!Your kernel has setup MSR instruction but ");
154 		pr_cont("CPU don't have it %x\n", msr);
155 	}
156 #else
157 	if (!msr) {
158 		pr_info("!!!Your kernel not setup MSR instruction but ");
159 		pr_cont("CPU have it %x\n", msr);
160 	}
161 #endif
162 
163 	/* Do not copy reset vectors. offset = 0x2 means skip the first
164 	 * two instructions. dst is pointer to MB vectors which are placed
165 	 * in block ram. If you want to copy reset vector setup offset to 0x0 */
166 #if !CONFIG_MANUAL_RESET_VECTOR
167 	offset = 0x2;
168 #endif
169 	dst = (unsigned long *) (offset * sizeof(u32));
170 	for (src = __ivt_start + offset; src < __ivt_end; src++, dst++)
171 		*dst = *src;
172 
173 	/* Initialize global data */
174 	per_cpu(KM, 0) = 0x1;	/* We start in kernel mode */
175 	per_cpu(CURRENT_SAVE, 0) = (unsigned long)current;
176 }
177 
178 void __init time_init(void)
179 {
180 	of_clk_init(NULL);
181 	setup_cpuinfo_clk();
182 	timer_probe();
183 }
184 
185 #ifdef CONFIG_DEBUG_FS
186 struct dentry *of_debugfs_root;
187 
188 static int microblaze_debugfs_init(void)
189 {
190 	of_debugfs_root = debugfs_create_dir("microblaze", NULL);
191 	return 0;
192 }
193 arch_initcall(microblaze_debugfs_init);
194 
195 # ifdef CONFIG_MMU
196 static int __init debugfs_tlb(void)
197 {
198 	debugfs_create_u32("tlb_skip", S_IRUGO, of_debugfs_root, &tlb_skip);
199 	return 0;
200 }
201 device_initcall(debugfs_tlb);
202 # endif
203 #endif
204