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Release 4.14 arch/nios2/kernel/setup.c

Directory: arch/nios2/kernel
/*
 * Nios2-specific parts of system setup
 *
 * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
 * Copyright (C) 2004 Microtronix Datacom Ltd.
 * Copyright (C) 2001 Vic Phillips <vic@microtronix.com>
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License. See the file "COPYING" in the main directory of this archive
 * for more details.
 */

#include <linux/export.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/sched.h>
#include <linux/sched/task.h>
#include <linux/console.h>
#include <linux/bootmem.h>
#include <linux/initrd.h>
#include <linux/of_fdt.h>
#include <linux/screen_info.h>

#include <asm/mmu_context.h>
#include <asm/sections.h>
#include <asm/setup.h>
#include <asm/cpuinfo.h>


unsigned long memory_start;

EXPORT_SYMBOL(memory_start);


unsigned long memory_end;

EXPORT_SYMBOL(memory_end);


unsigned long memory_size;


static struct pt_regs fake_regs = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
					0, 0, 0, 0, 0, 0,
					0};

#ifdef CONFIG_VT

struct screen_info screen_info;
#endif

/* Copy a short hook instruction sequence to the exception address */



static inline void copy_exception_handler(unsigned int addr)
{
	unsigned int start = (unsigned int) exception_handler_hook;
	volatile unsigned int tmp = 0;

	if (start == addr) {
		/* The CPU exception address already points to the handler. */
		return;
	}

	__asm__ __volatile__ (
                "ldw    %2,0(%0)\n"
                "stw    %2,0(%1)\n"
                "ldw    %2,4(%0)\n"
                "stw    %2,4(%1)\n"
                "ldw    %2,8(%0)\n"
                "stw    %2,8(%1)\n"
                "flushd 0(%1)\n"
                "flushd 4(%1)\n"
                "flushd 8(%1)\n"
                "flushi %1\n"
                "addi   %1,%1,4\n"
                "flushi %1\n"
                "addi   %1,%1,4\n"
                "flushi %1\n"
                "flushp\n"
                : /* no output registers */
		: "r" (start), "r" (addr), "r" (tmp)
                : "memory"
        );
}


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Ley Foon Tan43100.00%1100.00%


Total43100.00%1100.00%



/* Copy the fast TLB miss handler */



static inline void copy_fast_tlb_miss_handler(unsigned int addr)
{
	unsigned int start = (unsigned int) fast_handler;
	unsigned int end = (unsigned int) fast_handler_end;
	volatile unsigned int tmp = 0;

	__asm__ __volatile__ (
                "1:\n"
                "       ldw     %3,0(%0)\n"
                "       stw     %3,0(%1)\n"
                "       flushd  0(%1)\n"
                "       flushi  %1\n"
                "       flushp\n"
                "       addi    %0,%0,4\n"
                "       addi    %1,%1,4\n"
                "       bne     %0,%2,1b\n"
                : /* no output registers */
		: "r" (start), "r" (addr), "r" (end), "r" (tmp)
                : "memory"
        );
}


Contributors
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Ley Foon Tan43100.00%1100.00%


Total43100.00%1100.00%



/*
 * save args passed from u-boot, called from head.S
 *
 * @r4: NIOS magic
 * @r5: initrd start
 * @r6: initrd end or fdt
 * @r7: kernel command line
 */



asmlinkage void __init nios2_boot_init(unsigned r4, unsigned r5, unsigned r6,
				       unsigned r7)
{
	unsigned dtb_passed = 0;
	char cmdline_passed[COMMAND_LINE_SIZE] __maybe_unused = { 0, };

#if defined(CONFIG_NIOS2_PASS_CMDLINE)
	if (r4 == 0x534f494e) { /* r4 is magic NIOS */
#if defined(CONFIG_BLK_DEV_INITRD)
		if (r5) { /* initramfs */
			initrd_start = r5;
			initrd_end = r6;
		}
#endif /* CONFIG_BLK_DEV_INITRD */
		dtb_passed = r6;

		if (r7)
			strncpy(cmdline_passed, (char *)r7, COMMAND_LINE_SIZE);
	}
#endif

	early_init_devtree((void *)dtb_passed);

#ifndef CONFIG_CMDLINE_FORCE
	if (cmdline_passed[0])
		strncpy(boot_command_line, cmdline_passed, COMMAND_LINE_SIZE);
#ifdef CONFIG_NIOS2_CMDLINE_IGNORE_DTB
	else
		strncpy(boot_command_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
#endif
#endif

	parse_early_param();
}


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Ley Foon Tan14197.24%133.33%


Tobias Klauser32.07%133.33%


Marek Vašut10.69%133.33%


Total145100.00%3100.00%






void __init setup_arch(char **cmdline_p)
{
	int bootmap_size;

	console_verbose();

	memory_start = PAGE_ALIGN((unsigned long)__pa(_end));
	memory_end = (unsigned long) CONFIG_NIOS2_MEM_BASE + memory_size;

	init_mm.start_code = (unsigned long) _stext;
	init_mm.end_code = (unsigned long) _etext;
	init_mm.end_data = (unsigned long) _edata;
	init_mm.brk = (unsigned long) _end;
	init_task.thread.kregs = &fake_regs;

	/* Keep a copy of command line */
	*cmdline_p = boot_command_line;

	min_low_pfn = PFN_UP(memory_start);
	max_low_pfn = PFN_DOWN(memory_end);
	max_mapnr = max_low_pfn;

	/*
         * give all the memory to the bootmap allocator,  tell it to put the
         * boot mem_map at the start of memory
         */
	pr_debug("init_bootmem_node(?,%#lx, %#x, %#lx)\n",
		min_low_pfn, PFN_DOWN(PHYS_OFFSET), max_low_pfn);
	bootmap_size = init_bootmem_node(NODE_DATA(0),
					min_low_pfn, PFN_DOWN(PHYS_OFFSET),
					max_low_pfn);

	/*
         * free the usable memory,  we have to make sure we do not free
         * the bootmem bitmap so we then reserve it after freeing it :-)
         */
	pr_debug("free_bootmem(%#lx, %#lx)\n",
		memory_start, memory_end - memory_start);
	free_bootmem(memory_start, memory_end - memory_start);

	/*
         * 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
         */
	pr_debug("reserve_bootmem(%#lx, %#x)\n", memory_start, bootmap_size);
	reserve_bootmem(memory_start, bootmap_size, BOOTMEM_DEFAULT);

#ifdef CONFIG_BLK_DEV_INITRD
	if (initrd_start) {
		reserve_bootmem(virt_to_phys((void *)initrd_start),
				initrd_end - initrd_start, BOOTMEM_DEFAULT);
	}
#endif /* CONFIG_BLK_DEV_INITRD */

	early_init_fdt_reserve_self();
	early_init_fdt_scan_reserved_mem();

	unflatten_and_copy_device_tree();

	setup_cpuinfo();

	copy_exception_handler(cpuinfo.exception_addr);

	mmu_init();

	copy_fast_tlb_miss_handler(cpuinfo.fast_tlb_miss_exc_addr);

	/*
         * Initialize MMU context handling here because data from cpuinfo is
         * needed for this.
         */
	mmu_context_init();

	/*
         * get kmalloc into gear
         */
	paging_init();

#if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE)
	conswitchp = &dummy_con;
#endif
}

Contributors
PersonTokensPropCommitsCommitProp
Ley Foon Tan26797.80%150.00%


Tobias Klauser62.20%150.00%


Total273100.00%2100.00%




Overall Contributors
PersonTokensPropCommitsCommitProp
Ley Foon Tan61997.94%233.33%


Tobias Klauser91.42%233.33%


Ingo Molnar30.47%116.67%


Marek Vašut10.16%116.67%


Total632100.00%6100.00%


Directory: arch/nios2/kernel



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