xref: /openbmc/linux/arch/microblaze/kernel/setup.c (revision da1d9caf)
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/of_clk.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 #include <linux/pgtable.h>
22 
23 #include <asm/setup.h>
24 #include <asm/sections.h>
25 #include <asm/page.h>
26 #include <linux/io.h>
27 #include <linux/bug.h>
28 #include <linux/param.h>
29 #include <linux/pci.h>
30 #include <linux/cache.h>
31 #include <linux/of.h>
32 #include <linux/dma-mapping.h>
33 #include <asm/cacheflush.h>
34 #include <asm/entry.h>
35 #include <asm/cpuinfo.h>
36 
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 /*
45  * Placed cmd_line to .data section because can be initialized from
46  * ASM code. Default position is BSS section which is cleared
47  * in machine_early_init().
48  */
49 char cmd_line[COMMAND_LINE_SIZE] __section(".data");
50 
51 void __init setup_arch(char **cmdline_p)
52 {
53 	*cmdline_p = boot_command_line;
54 
55 	setup_memory();
56 
57 	console_verbose();
58 
59 	unflatten_device_tree();
60 
61 	setup_cpuinfo();
62 
63 	microblaze_cache_init();
64 
65 	xilinx_pci_init();
66 }
67 
68 #ifdef CONFIG_MTD_UCLINUX
69 /* Handle both romfs and cramfs types, without generating unnecessary
70  code (ie no point checking for CRAMFS if it's not even enabled) */
71 inline unsigned get_romfs_len(unsigned *addr)
72 {
73 #ifdef CONFIG_ROMFS_FS
74 	if (memcmp(&addr[0], "-rom1fs-", 8) == 0) /* romfs */
75 		return be32_to_cpu(addr[2]);
76 #endif
77 
78 #ifdef CONFIG_CRAMFS
79 	if (addr[0] == le32_to_cpu(0x28cd3d45)) /* cramfs */
80 		return le32_to_cpu(addr[1]);
81 #endif
82 	return 0;
83 }
84 #endif	/* CONFIG_MTD_UCLINUX_EBSS */
85 
86 unsigned long kernel_tlb;
87 
88 void __init machine_early_init(const char *cmdline, unsigned int ram,
89 		unsigned int fdt, unsigned int msr, unsigned int tlb0,
90 		unsigned int tlb1)
91 {
92 	unsigned long *src, *dst;
93 	unsigned int offset = 0;
94 
95 	/* If CONFIG_MTD_UCLINUX is defined, assume ROMFS is at the
96 	 * end of kernel. There are two position which we want to check.
97 	 * The first is __init_end and the second __bss_start.
98 	 */
99 #ifdef CONFIG_MTD_UCLINUX
100 	int romfs_size;
101 	unsigned int romfs_base;
102 	char *old_klimit = klimit;
103 
104 	romfs_base = (ram ? ram : (unsigned int)&__init_end);
105 	romfs_size = PAGE_ALIGN(get_romfs_len((unsigned *)romfs_base));
106 	if (!romfs_size) {
107 		romfs_base = (unsigned int)&__bss_start;
108 		romfs_size = PAGE_ALIGN(get_romfs_len((unsigned *)romfs_base));
109 	}
110 
111 	/* Move ROMFS out of BSS before clearing it */
112 	if (romfs_size > 0) {
113 		memmove(&__bss_stop, (int *)romfs_base, romfs_size);
114 		klimit += romfs_size;
115 	}
116 #endif
117 
118 /* clearing bss section */
119 	memset(__bss_start, 0, __bss_stop-__bss_start);
120 	memset(_ssbss, 0, _esbss-_ssbss);
121 
122 /* initialize device tree for usage in early_printk */
123 	early_init_devtree(_fdt_start);
124 
125 	/* setup kernel_tlb after BSS cleaning
126 	 * Maybe worth to move to asm code */
127 	kernel_tlb = tlb0 + tlb1;
128 	/* printk("TLB1 0x%08x, TLB0 0x%08x, tlb 0x%x\n", tlb0,
129 							tlb1, kernel_tlb); */
130 
131 	pr_info("Ramdisk addr 0x%08x, ", ram);
132 	if (fdt)
133 		pr_info("FDT at 0x%08x\n", fdt);
134 	else
135 		pr_info("Compiled-in FDT at %p\n", _fdt_start);
136 
137 #ifdef CONFIG_MTD_UCLINUX
138 	pr_info("Found romfs @ 0x%08x (0x%08x)\n",
139 			romfs_base, romfs_size);
140 	pr_info("#### klimit %p ####\n", old_klimit);
141 	BUG_ON(romfs_size < 0); /* What else can we do? */
142 
143 	pr_info("Moved 0x%08x bytes from 0x%08x to 0x%08x\n",
144 			romfs_size, romfs_base, (unsigned)&__bss_stop);
145 
146 	pr_info("New klimit: 0x%08x\n", (unsigned)klimit);
147 #endif
148 
149 #if CONFIG_XILINX_MICROBLAZE0_USE_MSR_INSTR
150 	if (msr) {
151 		pr_info("!!!Your kernel has setup MSR instruction but ");
152 		pr_cont("CPU don't have it %x\n", msr);
153 	}
154 #else
155 	if (!msr) {
156 		pr_info("!!!Your kernel not setup MSR instruction but ");
157 		pr_cont("CPU have it %x\n", msr);
158 	}
159 #endif
160 
161 	/* Do not copy reset vectors. offset = 0x2 means skip the first
162 	 * two instructions. dst is pointer to MB vectors which are placed
163 	 * in block ram. If you want to copy reset vector setup offset to 0x0 */
164 #if !CONFIG_MANUAL_RESET_VECTOR
165 	offset = 0x2;
166 #endif
167 	dst = (unsigned long *) (offset * sizeof(u32));
168 	for (src = __ivt_start + offset; src < __ivt_end; src++, dst++)
169 		*dst = *src;
170 
171 	/* Initialize global data */
172 	per_cpu(KM, 0) = 0x1;	/* We start in kernel mode */
173 	per_cpu(CURRENT_SAVE, 0) = (unsigned long)current;
174 }
175 
176 void __init time_init(void)
177 {
178 	of_clk_init(NULL);
179 	setup_cpuinfo_clk();
180 	timer_probe();
181 }
182 
183 #ifdef CONFIG_DEBUG_FS
184 struct dentry *of_debugfs_root;
185 
186 static int microblaze_debugfs_init(void)
187 {
188 	of_debugfs_root = debugfs_create_dir("microblaze", NULL);
189 	return 0;
190 }
191 arch_initcall(microblaze_debugfs_init);
192 
193 static int __init debugfs_tlb(void)
194 {
195 	debugfs_create_u32("tlb_skip", S_IRUGO, of_debugfs_root, &tlb_skip);
196 	return 0;
197 }
198 device_initcall(debugfs_tlb);
199 #endif
200