/* * * linux/arch/cris/kernel/setup.c * * Copyright (C) 1995 Linus Torvalds * Copyright (c) 2001 Axis Communications AB */ /* * This file handles the architecture-dependent parts of initialization */ #include <linux/init.h> #include <linux/mm.h> #include <linux/bootmem.h> #include <asm/pgtable.h> #include <linux/seq_file.h> #include <linux/screen_info.h> #include <linux/utsname.h> #include <linux/pfn.h> #include <linux/cpu.h> #include <asm/setup.h> #include <arch/system.h> /* * Setup options */ struct screen_info screen_info; extern int root_mountflags; extern char _etext, _edata, _end; char __initdata cris_command_line[COMMAND_LINE_SIZE] = { 0, }; extern const unsigned long text_start, edata; /* set by the linker script */ extern unsigned long dram_start, dram_end; extern unsigned long romfs_start, romfs_length, romfs_in_flash; /* from head.S */ static struct cpu cpu_devices[NR_CPUS]; extern void show_etrax_copyright(void); /* arch-vX/kernel/setup.c */ /* This mainly sets up the memory area, and can be really confusing. * * The physical DRAM is virtually mapped into dram_start to dram_end * (usually c0000000 to c0000000 + DRAM size). The physical address is * given by the macro __pa(). * * In this DRAM, the kernel code and data is loaded, in the beginning. * It really starts at c0004000 to make room for some special pages - * the start address is text_start. The kernel data ends at _end. After * this the ROM filesystem is appended (if there is any). * * Between this address and dram_end, we have RAM pages usable to the * boot code and the system. * */ void __init setup_arch(char **cmdline_p) { extern void init_etrax_debug(void); unsigned long bootmap_size; unsigned long start_pfn, max_pfn; unsigned long memory_start; /* register an initial console printing routine for printk's */ init_etrax_debug(); /* we should really poll for DRAM size! */ high_memory = &dram_end; if(romfs_in_flash || !romfs_length) { /* if we have the romfs in flash, or if there is no rom filesystem, * our free area starts directly after the BSS */ memory_start = (unsigned long) &_end; } else { /* otherwise the free area starts after the ROM filesystem */ printk("ROM fs in RAM, size %lu bytes\n", romfs_length); memory_start = romfs_start + romfs_length; } /* process 1's initial memory region is the kernel code/data */ init_mm.start_code = (unsigned long) &text_start; init_mm.end_code = (unsigned long) &_etext; init_mm.end_data = (unsigned long) &_edata; init_mm.brk = (unsigned long) &_end; /* min_low_pfn points to the start of DRAM, start_pfn points * to the first DRAM pages after the kernel, and max_low_pfn * to the end of DRAM. */ /* * partially used pages are not usable - thus * we are rounding upwards: */ start_pfn = PFN_UP(memory_start); /* usually c0000000 + kernel + romfs */ max_pfn = PFN_DOWN((unsigned long)high_memory); /* usually c0000000 + dram size */ /* * Initialize the boot-time allocator (start, end) * * We give it access to all our DRAM, but we could as well just have * given it a small slice. No point in doing that though, unless we * have non-contiguous memory and want the boot-stuff to be in, say, * the smallest area. * * It will put a bitmap of the allocated pages in the beginning * of the range we give it, but it won't mark the bitmaps pages * as reserved. We have to do that ourselves below. * * We need to use init_bootmem_node instead of init_bootmem * because our map starts at a quite high address (min_low_pfn). */ max_low_pfn = max_pfn; min_low_pfn = PAGE_OFFSET >> PAGE_SHIFT; bootmap_size = init_bootmem_node(NODE_DATA(0), start_pfn, min_low_pfn, max_low_pfn); /* And free all memory not belonging to the kernel (addr, size) */ free_bootmem(PFN_PHYS(start_pfn), PFN_PHYS(max_pfn - start_pfn)); /* * Reserve the bootmem bitmap itself as well. We do this in two * steps (first step was init_bootmem()) because this catches * the (very unlikely) case of us accidentally initializing the * bootmem allocator with an invalid RAM area. * * Arguments are start, size */ reserve_bootmem(PFN_PHYS(start_pfn), bootmap_size, BOOTMEM_DEFAULT); /* paging_init() sets up the MMU and marks all pages as reserved */ paging_init(); *cmdline_p = cris_command_line; #ifdef CONFIG_ETRAX_CMDLINE if (!strcmp(cris_command_line, "")) { strlcpy(cris_command_line, CONFIG_ETRAX_CMDLINE, COMMAND_LINE_SIZE); cris_command_line[COMMAND_LINE_SIZE - 1] = '\0'; } #endif /* Save command line for future references. */ memcpy(boot_command_line, cris_command_line, COMMAND_LINE_SIZE); boot_command_line[COMMAND_LINE_SIZE - 1] = '\0'; /* give credit for the CRIS port */ show_etrax_copyright(); /* Setup utsname */ strcpy(init_utsname()->machine, cris_machine_name); } static void *c_start(struct seq_file *m, loff_t *pos) { return *pos < nr_cpu_ids ? (void *)(int)(*pos + 1) : NULL; } static void *c_next(struct seq_file *m, void *v, loff_t *pos) { ++*pos; return c_start(m, pos); } static void c_stop(struct seq_file *m, void *v) { } extern int show_cpuinfo(struct seq_file *m, void *v); const struct seq_operations cpuinfo_op = { .start = c_start, .next = c_next, .stop = c_stop, .show = show_cpuinfo, }; static int __init topology_init(void) { int i; for_each_possible_cpu(i) { return register_cpu(&cpu_devices[i], i); } return 0; } subsys_initcall(topology_init);