arch/riscv/kernel/setup.c - linux - Git at Google

 /*
  * Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
  *  Chen Liqin <liqin.chen@sunplusct.com>
  *  Lennox Wu <lennox.wu@sunplusct.com>
  * Copyright (C) 2012 Regents of the University of California
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, see the file COPYING, or write
  * to the Free Software Foundation, Inc.,
  */

 #include <linux/init.h>
 #include <linux/mm.h>
 #include <linux/memblock.h>
 #include <linux/sched.h>
 #include <linux/initrd.h>
 #include <linux/console.h>
 #include <linux/screen_info.h>
 #include <linux/of_fdt.h>
 #include <linux/of_platform.h>
 #include <linux/sched/task.h>
 #include <linux/swiotlb.h>

 #include <asm/setup.h>
 #include <asm/sections.h>
 #include <asm/pgtable.h>
 #include <asm/smp.h>
 #include <asm/sbi.h>
 #include <asm/tlbflush.h>
 #include <asm/thread_info.h>

 #ifdef CONFIG_EARLY_PRINTK
 static void sbi_console_write(struct console *co, const char *buf,
 			      unsigned int n)
 {
 	int i;

 	for (i = 0; i < n; ++i) {
 		if (buf[i] == '\n')
 			sbi_console_putchar('\r');
 		sbi_console_putchar(buf[i]);
 	}
 }

 struct console riscv_sbi_early_console_dev __initdata = {
 	.name	= "early",
 	.write	= sbi_console_write,
 	.flags	= CON_PRINTBUFFER | CON_BOOT | CON_ANYTIME,
 	.index	= -1
 };
 #endif

 #ifdef CONFIG_DUMMY_CONSOLE
 struct screen_info screen_info = {
 	.orig_video_lines	= 30,
 	.orig_video_cols	= 80,
 	.orig_video_mode	= 0,
 	.orig_video_ega_bx	= 0,
 	.orig_video_isVGA	= 1,
 	.orig_video_points	= 8
 };
 #endif

 unsigned long va_pa_offset;
 EXPORT_SYMBOL(va_pa_offset);
 unsigned long pfn_base;
 EXPORT_SYMBOL(pfn_base);

 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss;
 EXPORT_SYMBOL(empty_zero_page);

 /* The lucky hart to first increment this variable will boot the other cores */
 atomic_t hart_lottery;
 unsigned long boot_cpu_hartid;

 unsigned long __cpuid_to_hartid_map[NR_CPUS] = {
 	[0 ... NR_CPUS-1] = INVALID_HARTID
 };

 void __init smp_setup_processor_id(void)
 {
 	cpuid_to_hartid_map(0) = boot_cpu_hartid;
 }

 #ifdef CONFIG_BLK_DEV_INITRD
 static void __init setup_initrd(void)
 {
 	unsigned long size;

 	if (initrd_start >= initrd_end) {
 		printk(KERN_INFO "initrd not found or empty");
 		goto disable;
 	}
 	if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) {
 		printk(KERN_ERR "initrd extends beyond end of memory");
 		goto disable;
 	}

 	size =  initrd_end - initrd_start;
 	memblock_reserve(__pa(initrd_start), size);
 	initrd_below_start_ok = 1;

 	printk(KERN_INFO "Initial ramdisk at: 0x%p (%lu bytes)\n",
 		(void *)(initrd_start), size);
 	return;
 disable:
 	pr_cont(" - disabling initrd\n");
 	initrd_start = 0;
 	initrd_end = 0;
 }
 #endif /* CONFIG_BLK_DEV_INITRD */

 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
 pgd_t trampoline_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);

 #ifndef __PAGETABLE_PMD_FOLDED
 #define NUM_SWAPPER_PMDS ((uintptr_t)-PAGE_OFFSET >> PGDIR_SHIFT)
 pmd_t swapper_pmd[PTRS_PER_PMD*((-PAGE_OFFSET)/PGDIR_SIZE)] __page_aligned_bss;
 pmd_t trampoline_pmd[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
 #endif

 asmlinkage void __init setup_vm(void)
 {
 	extern char _start;
 	uintptr_t i;
 	uintptr_t pa = (uintptr_t) &_start;
 	pgprot_t prot = __pgprot(pgprot_val(PAGE_KERNEL) | _PAGE_EXEC);

 	va_pa_offset = PAGE_OFFSET - pa;
 	pfn_base = PFN_DOWN(pa);

 	/* Sanity check alignment and size */
 	BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0);
 	BUG_ON((pa % (PAGE_SIZE * PTRS_PER_PTE)) != 0);

 #ifndef __PAGETABLE_PMD_FOLDED
 	trampoline_pg_dir[(PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD] =
 		pfn_pgd(PFN_DOWN((uintptr_t)trampoline_pmd),
 			__pgprot(_PAGE_TABLE));
 	trampoline_pmd[0] = pfn_pmd(PFN_DOWN(pa), prot);

 	for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) {
 		size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i;
 		swapper_pg_dir[o] =
 			pfn_pgd(PFN_DOWN((uintptr_t)swapper_pmd) + i,
 				__pgprot(_PAGE_TABLE));
 	}
 	for (i = 0; i < ARRAY_SIZE(swapper_pmd); i++)
 		swapper_pmd[i] = pfn_pmd(PFN_DOWN(pa + i * PMD_SIZE), prot);
 #else
 	trampoline_pg_dir[(PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD] =
 		pfn_pgd(PFN_DOWN(pa), prot);

 	for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) {
 		size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i;
 		swapper_pg_dir[o] =
 			pfn_pgd(PFN_DOWN(pa + i * PGDIR_SIZE), prot);
 	}
 #endif
 }

 void __init parse_dtb(unsigned int hartid, void *dtb)
 {
 	early_init_dt_scan(__va(dtb));
 }

 static void __init setup_bootmem(void)
 {
 	struct memblock_region *reg;
 	phys_addr_t mem_size = 0;

 	/* Find the memory region containing the kernel */
 	for_each_memblock(memory, reg) {
 		phys_addr_t vmlinux_end = __pa(_end);
 		phys_addr_t end = reg->base + reg->size;

 		if (reg->base <= vmlinux_end && vmlinux_end <= end) {
 			/*
 			 * Reserve from the start of the region to the end of
 			 * the kernel
 			 */
 			memblock_reserve(reg->base, vmlinux_end - reg->base);
 			mem_size = min(reg->size, (phys_addr_t)-PAGE_OFFSET);
 		}
 	}
 	BUG_ON(mem_size == 0);

 	set_max_mapnr(PFN_DOWN(mem_size));
 	max_low_pfn = memblock_end_of_DRAM();

 #ifdef CONFIG_BLK_DEV_INITRD
 	setup_initrd();
 #endif /* CONFIG_BLK_DEV_INITRD */

 	early_init_fdt_reserve_self();
 	early_init_fdt_scan_reserved_mem();
 	memblock_allow_resize();
 	memblock_dump_all();

 	for_each_memblock(memory, reg) {
 		unsigned long start_pfn = memblock_region_memory_base_pfn(reg);
 		unsigned long end_pfn = memblock_region_memory_end_pfn(reg);

 		memblock_set_node(PFN_PHYS(start_pfn),
 		                  PFN_PHYS(end_pfn - start_pfn),
 		                  &memblock.memory, 0);
 	}
 }

 void __init setup_arch(char **cmdline_p)
 {
 #if defined(CONFIG_EARLY_PRINTK)
        if (likely(early_console == NULL)) {
                early_console = &riscv_sbi_early_console_dev;
                register_console(early_console);
        }
 #endif
 	*cmdline_p = boot_command_line;

 	parse_early_param();

 	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;

 	setup_bootmem();
 	paging_init();
 	unflatten_device_tree();

 #ifdef CONFIG_SWIOTLB
 	swiotlb_init(1);
 #endif

 #ifdef CONFIG_SMP
 	setup_smp();
 #endif

 #ifdef CONFIG_DUMMY_CONSOLE
 	conswitchp = &dummy_con;
 #endif

 	riscv_fill_hwcap();
 }
	/*
	* Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
	* Chen Liqin <liqin.chen@sunplusct.com>
	* Lennox Wu <lennox.wu@sunplusct.com>
	* Copyright (C) 2012 Regents of the University of California
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, see the file COPYING, or write
	* to the Free Software Foundation, Inc.,
	*/

	#include <linux/init.h>
	#include <linux/mm.h>
	#include <linux/memblock.h>
	#include <linux/sched.h>
	#include <linux/initrd.h>
	#include <linux/console.h>
	#include <linux/screen_info.h>
	#include <linux/of_fdt.h>
	#include <linux/of_platform.h>
	#include <linux/sched/task.h>
	#include <linux/swiotlb.h>

	#include <asm/setup.h>
	#include <asm/sections.h>
	#include <asm/pgtable.h>
	#include <asm/smp.h>
	#include <asm/sbi.h>
	#include <asm/tlbflush.h>
	#include <asm/thread_info.h>

	#ifdef CONFIG_EARLY_PRINTK
	static void sbi_console_write(struct console co, const char buf,
	unsigned int n)
	{
	int i;

	for (i = 0; i < n; ++i) {
	if (buf[i] == '\n')
	sbi_console_putchar('\r');
	sbi_console_putchar(buf[i]);
	}
	}

	struct console riscv_sbi_early_console_dev __initdata = {
	.name = "early",
	.write = sbi_console_write,
	.flags = CON_PRINTBUFFER \| CON_BOOT \| CON_ANYTIME,
	.index = -1
	};
	#endif

	#ifdef CONFIG_DUMMY_CONSOLE
	struct screen_info screen_info = {
	.orig_video_lines = 30,
	.orig_video_cols = 80,
	.orig_video_mode = 0,
	.orig_video_ega_bx = 0,
	.orig_video_isVGA = 1,
	.orig_video_points = 8
	};
	#endif

	unsigned long va_pa_offset;
	EXPORT_SYMBOL(va_pa_offset);
	unsigned long pfn_base;
	EXPORT_SYMBOL(pfn_base);

	unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss;
	EXPORT_SYMBOL(empty_zero_page);

	/* The lucky hart to first increment this variable will boot the other cores */
	atomic_t hart_lottery;
	unsigned long boot_cpu_hartid;

	unsigned long __cpuid_to_hartid_map[NR_CPUS] = {
	[0 ... NR_CPUS-1] = INVALID_HARTID
	};

	void __init smp_setup_processor_id(void)
	{
	cpuid_to_hartid_map(0) = boot_cpu_hartid;
	}

	#ifdef CONFIG_BLK_DEV_INITRD
	static void __init setup_initrd(void)
	{
	unsigned long size;

	if (initrd_start >= initrd_end) {
	printk(KERN_INFO "initrd not found or empty");
	goto disable;
	}
	if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) {
	printk(KERN_ERR "initrd extends beyond end of memory");
	goto disable;
	}

	size = initrd_end - initrd_start;
	memblock_reserve(__pa(initrd_start), size);
	initrd_below_start_ok = 1;

	printk(KERN_INFO "Initial ramdisk at: 0x%p (%lu bytes)\n",
	(void *)(initrd_start), size);
	return;
	disable:
	pr_cont(" - disabling initrd\n");
	initrd_start = 0;
	initrd_end = 0;
	}
	#endif /* CONFIG_BLK_DEV_INITRD */

	pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
	pgd_t trampoline_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);

	#ifndef __PAGETABLE_PMD_FOLDED
	#define NUM_SWAPPER_PMDS ((uintptr_t)-PAGE_OFFSET >> PGDIR_SHIFT)
	pmd_t swapper_pmd[PTRS_PER_PMD*((-PAGE_OFFSET)/PGDIR_SIZE)] __page_aligned_bss;
	pmd_t trampoline_pmd[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
	#endif

	asmlinkage void __init setup_vm(void)
	{
	extern char _start;
	uintptr_t i;
	uintptr_t pa = (uintptr_t) &_start;
	pgprot_t prot = __pgprot(pgprot_val(PAGE_KERNEL) \| _PAGE_EXEC);

	va_pa_offset = PAGE_OFFSET - pa;
	pfn_base = PFN_DOWN(pa);

	/* Sanity check alignment and size */
	BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0);
	BUG_ON((pa % (PAGE_SIZE * PTRS_PER_PTE)) != 0);

	#ifndef __PAGETABLE_PMD_FOLDED
	trampoline_pg_dir[(PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD] =
	pfn_pgd(PFN_DOWN((uintptr_t)trampoline_pmd),
	__pgprot(_PAGE_TABLE));
	trampoline_pmd[0] = pfn_pmd(PFN_DOWN(pa), prot);

	for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) {
	size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i;
	swapper_pg_dir[o] =
	pfn_pgd(PFN_DOWN((uintptr_t)swapper_pmd) + i,
	__pgprot(_PAGE_TABLE));
	}
	for (i = 0; i < ARRAY_SIZE(swapper_pmd); i++)
	swapper_pmd[i] = pfn_pmd(PFN_DOWN(pa + i * PMD_SIZE), prot);
	#else
	trampoline_pg_dir[(PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD] =
	pfn_pgd(PFN_DOWN(pa), prot);

	for (i = 0; i < (-PAGE_OFFSET)/PGDIR_SIZE; ++i) {
	size_t o = (PAGE_OFFSET >> PGDIR_SHIFT) % PTRS_PER_PGD + i;
	swapper_pg_dir[o] =
	pfn_pgd(PFN_DOWN(pa + i * PGDIR_SIZE), prot);
	}
	#endif
	}

	void __init parse_dtb(unsigned int hartid, void *dtb)
	{
	early_init_dt_scan(__va(dtb));
	}

	static void __init setup_bootmem(void)
	{
	struct memblock_region *reg;
	phys_addr_t mem_size = 0;

	/* Find the memory region containing the kernel */
	for_each_memblock(memory, reg) {
	phys_addr_t vmlinux_end = __pa(_end);
	phys_addr_t end = reg->base + reg->size;

	if (reg->base <= vmlinux_end && vmlinux_end <= end) {
	/*
	* Reserve from the start of the region to the end of
	* the kernel
	*/
	memblock_reserve(reg->base, vmlinux_end - reg->base);
	mem_size = min(reg->size, (phys_addr_t)-PAGE_OFFSET);
	}
	}
	BUG_ON(mem_size == 0);

	set_max_mapnr(PFN_DOWN(mem_size));
	max_low_pfn = memblock_end_of_DRAM();

	#ifdef CONFIG_BLK_DEV_INITRD
	setup_initrd();
	#endif /* CONFIG_BLK_DEV_INITRD */

	early_init_fdt_reserve_self();
	early_init_fdt_scan_reserved_mem();
	memblock_allow_resize();
	memblock_dump_all();

	for_each_memblock(memory, reg) {
	unsigned long start_pfn = memblock_region_memory_base_pfn(reg);
	unsigned long end_pfn = memblock_region_memory_end_pfn(reg);

	memblock_set_node(PFN_PHYS(start_pfn),
	PFN_PHYS(end_pfn - start_pfn),
	&memblock.memory, 0);
	}
	}

	void __init setup_arch(char **cmdline_p)
	{
	#if defined(CONFIG_EARLY_PRINTK)
	if (likely(early_console == NULL)) {
	early_console = &riscv_sbi_early_console_dev;
	register_console(early_console);
	}
	#endif
	*cmdline_p = boot_command_line;

	parse_early_param();

	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;

	setup_bootmem();
	paging_init();
	unflatten_device_tree();

	#ifdef CONFIG_SWIOTLB
	swiotlb_init(1);
	#endif

	#ifdef CONFIG_SMP
	setup_smp();
	#endif

	#ifdef CONFIG_DUMMY_CONSOLE
	conswitchp = &dummy_con;
	#endif

	riscv_fill_hwcap();
	}