arch/microblaze/kernel/setup.c

   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