xref: /openbmc/linux/arch/microblaze/kernel/setup.c (revision 9cfc5c90)
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_platform.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/prom.h>
37 #include <asm/pgtable.h>
38 
39 DEFINE_PER_CPU(unsigned int, KSP);	/* Saved kernel stack pointer */
40 DEFINE_PER_CPU(unsigned int, KM);	/* Kernel/user mode */
41 DEFINE_PER_CPU(unsigned int, ENTRY_SP);	/* Saved SP on kernel entry */
42 DEFINE_PER_CPU(unsigned int, R11_SAVE);	/* Temp variable for entry */
43 DEFINE_PER_CPU(unsigned int, CURRENT_SAVE);	/* Saved current pointer */
44 
45 unsigned int boot_cpuid;
46 /*
47  * Placed cmd_line to .data section because can be initialized from
48  * ASM code. Default position is BSS section which is cleared
49  * in machine_early_init().
50  */
51 char cmd_line[COMMAND_LINE_SIZE] __attribute__ ((section(".data")));
52 
53 void __init setup_arch(char **cmdline_p)
54 {
55 	*cmdline_p = boot_command_line;
56 
57 	console_verbose();
58 
59 	unflatten_device_tree();
60 
61 	setup_cpuinfo();
62 
63 	microblaze_cache_init();
64 
65 	setup_memory();
66 
67 #ifdef CONFIG_EARLY_PRINTK
68 	/* remap early console to virtual address */
69 	remap_early_printk();
70 #endif
71 
72 	xilinx_pci_init();
73 
74 #if defined(CONFIG_DUMMY_CONSOLE)
75 	conswitchp = &dummy_con;
76 #endif
77 }
78 
79 #ifdef CONFIG_MTD_UCLINUX
80 /* Handle both romfs and cramfs types, without generating unnecessary
81  code (ie no point checking for CRAMFS if it's not even enabled) */
82 inline unsigned get_romfs_len(unsigned *addr)
83 {
84 #ifdef CONFIG_ROMFS_FS
85 	if (memcmp(&addr[0], "-rom1fs-", 8) == 0) /* romfs */
86 		return be32_to_cpu(addr[2]);
87 #endif
88 
89 #ifdef CONFIG_CRAMFS
90 	if (addr[0] == le32_to_cpu(0x28cd3d45)) /* cramfs */
91 		return le32_to_cpu(addr[1]);
92 #endif
93 	return 0;
94 }
95 #endif	/* CONFIG_MTD_UCLINUX_EBSS */
96 
97 unsigned long kernel_tlb;
98 
99 void __init machine_early_init(const char *cmdline, unsigned int ram,
100 		unsigned int fdt, unsigned int msr, unsigned int tlb0,
101 		unsigned int tlb1)
102 {
103 	unsigned long *src, *dst;
104 	unsigned int offset = 0;
105 
106 	/* If CONFIG_MTD_UCLINUX is defined, assume ROMFS is at the
107 	 * end of kernel. There are two position which we want to check.
108 	 * The first is __init_end and the second __bss_start.
109 	 */
110 #ifdef CONFIG_MTD_UCLINUX
111 	int romfs_size;
112 	unsigned int romfs_base;
113 	char *old_klimit = klimit;
114 
115 	romfs_base = (ram ? ram : (unsigned int)&__init_end);
116 	romfs_size = PAGE_ALIGN(get_romfs_len((unsigned *)romfs_base));
117 	if (!romfs_size) {
118 		romfs_base = (unsigned int)&__bss_start;
119 		romfs_size = PAGE_ALIGN(get_romfs_len((unsigned *)romfs_base));
120 	}
121 
122 	/* Move ROMFS out of BSS before clearing it */
123 	if (romfs_size > 0) {
124 		memmove(&__bss_stop, (int *)romfs_base, romfs_size);
125 		klimit += romfs_size;
126 	}
127 #endif
128 
129 /* clearing bss section */
130 	memset(__bss_start, 0, __bss_stop-__bss_start);
131 	memset(_ssbss, 0, _esbss-_ssbss);
132 
133 	lockdep_init();
134 
135 /* initialize device tree for usage in early_printk */
136 	early_init_devtree(_fdt_start);
137 
138 #ifdef CONFIG_EARLY_PRINTK
139 	setup_early_printk(NULL);
140 #endif
141 
142 	/* setup kernel_tlb after BSS cleaning
143 	 * Maybe worth to move to asm code */
144 	kernel_tlb = tlb0 + tlb1;
145 	/* printk("TLB1 0x%08x, TLB0 0x%08x, tlb 0x%x\n", tlb0,
146 							tlb1, kernel_tlb); */
147 
148 	pr_info("Ramdisk addr 0x%08x, ", ram);
149 	if (fdt)
150 		pr_info("FDT at 0x%08x\n", fdt);
151 	else
152 		pr_info("Compiled-in FDT at %p\n", _fdt_start);
153 
154 #ifdef CONFIG_MTD_UCLINUX
155 	pr_info("Found romfs @ 0x%08x (0x%08x)\n",
156 			romfs_base, romfs_size);
157 	pr_info("#### klimit %p ####\n", old_klimit);
158 	BUG_ON(romfs_size < 0); /* What else can we do? */
159 
160 	pr_info("Moved 0x%08x bytes from 0x%08x to 0x%08x\n",
161 			romfs_size, romfs_base, (unsigned)&__bss_stop);
162 
163 	pr_info("New klimit: 0x%08x\n", (unsigned)klimit);
164 #endif
165 
166 #if CONFIG_XILINX_MICROBLAZE0_USE_MSR_INSTR
167 	if (msr) {
168 		pr_info("!!!Your kernel has setup MSR instruction but ");
169 		pr_cont("CPU don't have it %x\n", msr);
170 	}
171 #else
172 	if (!msr) {
173 		pr_info("!!!Your kernel not setup MSR instruction but ");
174 		pr_cont("CPU have it %x\n", msr);
175 	}
176 #endif
177 
178 	/* Do not copy reset vectors. offset = 0x2 means skip the first
179 	 * two instructions. dst is pointer to MB vectors which are placed
180 	 * in block ram. If you want to copy reset vector setup offset to 0x0 */
181 #if !CONFIG_MANUAL_RESET_VECTOR
182 	offset = 0x2;
183 #endif
184 	dst = (unsigned long *) (offset * sizeof(u32));
185 	for (src = __ivt_start + offset; src < __ivt_end; src++, dst++)
186 		*dst = *src;
187 
188 	/* Initialize global data */
189 	per_cpu(KM, 0) = 0x1;	/* We start in kernel mode */
190 	per_cpu(CURRENT_SAVE, 0) = (unsigned long)current;
191 }
192 
193 void __init time_init(void)
194 {
195 	of_clk_init(NULL);
196 	setup_cpuinfo_clk();
197 	clocksource_probe();
198 }
199 
200 #ifdef CONFIG_DEBUG_FS
201 struct dentry *of_debugfs_root;
202 
203 static int microblaze_debugfs_init(void)
204 {
205 	of_debugfs_root = debugfs_create_dir("microblaze", NULL);
206 
207 	return of_debugfs_root == NULL;
208 }
209 arch_initcall(microblaze_debugfs_init);
210 
211 # ifdef CONFIG_MMU
212 static int __init debugfs_tlb(void)
213 {
214 	struct dentry *d;
215 
216 	if (!of_debugfs_root)
217 		return -ENODEV;
218 
219 	d = debugfs_create_u32("tlb_skip", S_IRUGO, of_debugfs_root, &tlb_skip);
220 	if (!d)
221 		return -ENOMEM;
222 
223 	return 0;
224 }
225 device_initcall(debugfs_tlb);
226 # endif
227 #endif
228