arch/arm64/kernel/setup.c - linux - Git at Google

 /*
  * Based on arch/arm/kernel/setup.c
  *
  * Copyright (C) 1995-2001 Russell King
  * Copyright (C) 2012 ARM Ltd.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  *
  * 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 <http://www.gnu.org/licenses/>.
  */

 #include <linux/export.h>
 #include <linux/kernel.h>
 #include <linux/stddef.h>
 #include <linux/ioport.h>
 #include <linux/delay.h>
 #include <linux/utsname.h>
 #include <linux/initrd.h>
 #include <linux/console.h>
 #include <linux/bootmem.h>
 #include <linux/seq_file.h>
 #include <linux/screen_info.h>
 #include <linux/init.h>
 #include <linux/kexec.h>
 #include <linux/crash_dump.h>
 #include <linux/root_dev.h>
 #include <linux/cpu.h>
 #include <linux/interrupt.h>
 #include <linux/smp.h>
 #include <linux/fs.h>
 #include <linux/proc_fs.h>
 #include <linux/memblock.h>
 #include <linux/of_fdt.h>

 #include <asm/cputype.h>
 #include <asm/elf.h>
 #include <asm/cputable.h>
 #include <asm/sections.h>
 #include <asm/setup.h>
 #include <asm/cacheflush.h>
 #include <asm/tlbflush.h>
 #include <asm/traps.h>
 #include <asm/memblock.h>

 unsigned int processor_id;
 EXPORT_SYMBOL(processor_id);

 unsigned int elf_hwcap __read_mostly;
 EXPORT_SYMBOL_GPL(elf_hwcap);

 static const char *cpu_name;
 static const char *machine_name;
 phys_addr_t __fdt_pointer __initdata;

 /*
  * Standard memory resources
  */
 static struct resource mem_res[] = {
 	{
 		.name = "Kernel code",
 		.start = 0,
 		.end = 0,
 		.flags = IORESOURCE_MEM
 	},
 	{
 		.name = "Kernel data",
 		.start = 0,
 		.end = 0,
 		.flags = IORESOURCE_MEM
 	}
 };

 #define kernel_code mem_res[0]
 #define kernel_data mem_res[1]

 void __init early_print(const char *str, ...)
 {
 	char buf[256];
 	va_list ap;

 	va_start(ap, str);
 	vsnprintf(buf, sizeof(buf), str, ap);
 	va_end(ap);

 	printk("%s", buf);
 }

 static void __init setup_processor(void)
 {
 	struct cpu_info *cpu_info;

 	/*
 	 * locate processor in the list of supported processor
 	 * types.  The linker builds this table for us from the
 	 * entries in arch/arm/mm/proc.S
 	 */
 	cpu_info = lookup_processor_type(read_cpuid_id());
 	if (!cpu_info) {
 		printk("CPU configuration botched (ID %08x), unable to continue.\n",
 		       read_cpuid_id());
 		while (1);
 	}

 	cpu_name = cpu_info->cpu_name;

 	printk("CPU: %s [%08x] revision %d\n",
 	       cpu_name, read_cpuid_id(), read_cpuid_id() & 15);

 	sprintf(init_utsname()->machine, "aarch64");
 	elf_hwcap = 0;
 }

 static void __init setup_machine_fdt(phys_addr_t dt_phys)
 {
 	struct boot_param_header *devtree;
 	unsigned long dt_root;

 	/* Check we have a non-NULL DT pointer */
 	if (!dt_phys) {
 		early_print("\n"
 			"Error: NULL or invalid device tree blob\n"
 			"The dtb must be 8-byte aligned and passed in the first 512MB of memory\n"
 			"\nPlease check your bootloader.\n");

 		while (true)
 			cpu_relax();

 	}

 	devtree = phys_to_virt(dt_phys);

 	/* Check device tree validity */
 	if (be32_to_cpu(devtree->magic) != OF_DT_HEADER) {
 		early_print("\n"
 			"Error: invalid device tree blob at physical address 0x%p (virtual address 0x%p)\n"
 			"Expected 0x%x, found 0x%x\n"
 			"\nPlease check your bootloader.\n",
 			dt_phys, devtree, OF_DT_HEADER,
 			be32_to_cpu(devtree->magic));

 		while (true)
 			cpu_relax();
 	}

 	initial_boot_params = devtree;
 	dt_root = of_get_flat_dt_root();

 	machine_name = of_get_flat_dt_prop(dt_root, "model", NULL);
 	if (!machine_name)
 		machine_name = of_get_flat_dt_prop(dt_root, "compatible", NULL);
 	if (!machine_name)
 		machine_name = "<unknown>";
 	pr_info("Machine: %s\n", machine_name);

 	/* Retrieve various information from the /chosen node */
 	of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
 	/* Initialize {size,address}-cells info */
 	of_scan_flat_dt(early_init_dt_scan_root, NULL);
 	/* Setup memory, calling early_init_dt_add_memory_arch */
 	of_scan_flat_dt(early_init_dt_scan_memory, NULL);
 }

 void __init early_init_dt_add_memory_arch(u64 base, u64 size)
 {
 	base &= PAGE_MASK;
 	size &= PAGE_MASK;
 	if (base + size < PHYS_OFFSET) {
 		pr_warning("Ignoring memory block 0x%llx - 0x%llx\n",
 			   base, base + size);
 		return;
 	}
 	if (base < PHYS_OFFSET) {
 		pr_warning("Ignoring memory range 0x%llx - 0x%llx\n",
 			   base, PHYS_OFFSET);
 		size -= PHYS_OFFSET - base;
 		base = PHYS_OFFSET;
 	}
 	memblock_add(base, size);
 }

 void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
 {
 	return __va(memblock_alloc(size, align));
 }

 /*
  * Limit the memory size that was specified via FDT.
  */
 static int __init early_mem(char *p)
 {
 	phys_addr_t limit;

 	if (!p)
 		return 1;

 	limit = memparse(p, &p) & PAGE_MASK;
 	pr_notice("Memory limited to %lldMB\n", limit >> 20);

 	memblock_enforce_memory_limit(limit);

 	return 0;
 }
 early_param("mem", early_mem);

 static void __init request_standard_resources(void)
 {
 	struct memblock_region *region;
 	struct resource *res;

 	kernel_code.start   = virt_to_phys(_text);
 	kernel_code.end     = virt_to_phys(_etext - 1);
 	kernel_data.start   = virt_to_phys(_sdata);
 	kernel_data.end     = virt_to_phys(_end - 1);

 	for_each_memblock(memory, region) {
 		res = alloc_bootmem_low(sizeof(*res));
 		res->name  = "System RAM";
 		res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
 		res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
 		res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;

 		request_resource(&iomem_resource, res);

 		if (kernel_code.start >= res->start &&
 		    kernel_code.end <= res->end)
 			request_resource(res, &kernel_code);
 		if (kernel_data.start >= res->start &&
 		    kernel_data.end <= res->end)
 			request_resource(res, &kernel_data);
 	}
 }

 void __init setup_arch(char **cmdline_p)
 {
 	setup_processor();

 	setup_machine_fdt(__fdt_pointer);

 	init_mm.start_code = (unsigned long) _text;
 	init_mm.end_code   = (unsigned long) _etext;
 	init_mm.end_data   = (unsigned long) _edata;
 	init_mm.brk	   = (unsigned long) _end;

 	*cmdline_p = boot_command_line;

 	parse_early_param();

 	arm64_memblock_init();

 	paging_init();
 	request_standard_resources();

 	unflatten_device_tree();

 #ifdef CONFIG_SMP
 	smp_init_cpus();
 #endif

 #ifdef CONFIG_VT
 #if defined(CONFIG_VGA_CONSOLE)
 	conswitchp = &vga_con;
 #elif defined(CONFIG_DUMMY_CONSOLE)
 	conswitchp = &dummy_con;
 #endif
 #endif
 }

 static DEFINE_PER_CPU(struct cpu, cpu_data);

 static int __init topology_init(void)
 {
 	int i;

 	for_each_possible_cpu(i) {
 		struct cpu *cpu = &per_cpu(cpu_data, i);
 		cpu->hotpluggable = 1;
 		register_cpu(cpu, i);
 	}

 	return 0;
 }
 subsys_initcall(topology_init);

 static const char *hwcap_str[] = {
 	"fp",
 	"asimd",
 	NULL
 };

 static int c_show(struct seq_file *m, void *v)
 {
 	int i;

 	seq_printf(m, "Processor\t: %s rev %d (%s)\n",
 		   cpu_name, read_cpuid_id() & 15, ELF_PLATFORM);

 	for_each_online_cpu(i) {
 		/*
 		 * glibc reads /proc/cpuinfo to determine the number of
 		 * online processors, looking for lines beginning with
 		 * "processor".  Give glibc what it expects.
 		 */
 #ifdef CONFIG_SMP
 		seq_printf(m, "processor\t: %d\n", i);
 #endif
 		seq_printf(m, "BogoMIPS\t: %lu.%02lu\n\n",
 			   loops_per_jiffy / (500000UL/HZ),
 			   loops_per_jiffy / (5000UL/HZ) % 100);
 	}

 	/* dump out the processor features */
 	seq_puts(m, "Features\t: ");

 	for (i = 0; hwcap_str[i]; i++)
 		if (elf_hwcap & (1 << i))
 			seq_printf(m, "%s ", hwcap_str[i]);

 	seq_printf(m, "\nCPU implementer\t: 0x%02x\n", read_cpuid_id() >> 24);
 	seq_printf(m, "CPU architecture: AArch64\n");
 	seq_printf(m, "CPU variant\t: 0x%x\n", (read_cpuid_id() >> 20) & 15);
 	seq_printf(m, "CPU part\t: 0x%03x\n", (read_cpuid_id() >> 4) & 0xfff);
 	seq_printf(m, "CPU revision\t: %d\n", read_cpuid_id() & 15);

 	seq_puts(m, "\n");

 	seq_printf(m, "Hardware\t: %s\n", machine_name);

 	return 0;
 }

 static void *c_start(struct seq_file *m, loff_t *pos)
 {
 	return *pos < 1 ? (void *)1 : NULL;
 }

 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
 {
 	++*pos;
 	return NULL;
 }

 static void c_stop(struct seq_file *m, void *v)
 {
 }

 const struct seq_operations cpuinfo_op = {
 	.start	= c_start,
 	.next	= c_next,
 	.stop	= c_stop,
 	.show	= c_show
 };
	/*
	* Based on arch/arm/kernel/setup.c
	*
	* Copyright (C) 1995-2001 Russell King
	* Copyright (C) 2012 ARM Ltd.
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 as
	* published by the Free Software Foundation.
	*
	* 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 <http://www.gnu.org/licenses/>.
	*/

	#include <linux/export.h>
	#include <linux/kernel.h>
	#include <linux/stddef.h>
	#include <linux/ioport.h>
	#include <linux/delay.h>
	#include <linux/utsname.h>
	#include <linux/initrd.h>
	#include <linux/console.h>
	#include <linux/bootmem.h>
	#include <linux/seq_file.h>
	#include <linux/screen_info.h>
	#include <linux/init.h>
	#include <linux/kexec.h>
	#include <linux/crash_dump.h>
	#include <linux/root_dev.h>
	#include <linux/cpu.h>
	#include <linux/interrupt.h>
	#include <linux/smp.h>
	#include <linux/fs.h>
	#include <linux/proc_fs.h>
	#include <linux/memblock.h>
	#include <linux/of_fdt.h>

	#include <asm/cputype.h>
	#include <asm/elf.h>
	#include <asm/cputable.h>
	#include <asm/sections.h>
	#include <asm/setup.h>
	#include <asm/cacheflush.h>
	#include <asm/tlbflush.h>
	#include <asm/traps.h>
	#include <asm/memblock.h>

	unsigned int processor_id;
	EXPORT_SYMBOL(processor_id);

	unsigned int elf_hwcap __read_mostly;
	EXPORT_SYMBOL_GPL(elf_hwcap);

	static const char *cpu_name;
	static const char *machine_name;
	phys_addr_t __fdt_pointer __initdata;

	/*
	* Standard memory resources
	*/
	static struct resource mem_res[] = {
	{
	.name = "Kernel code",
	.start = 0,
	.end = 0,
	.flags = IORESOURCE_MEM
	},
	{
	.name = "Kernel data",
	.start = 0,
	.end = 0,
	.flags = IORESOURCE_MEM
	}
	};

	#define kernel_code mem_res[0]
	#define kernel_data mem_res[1]

	void __init early_print(const char *str, ...)
	{
	char buf[256];
	va_list ap;

	va_start(ap, str);
	vsnprintf(buf, sizeof(buf), str, ap);
	va_end(ap);

	printk("%s", buf);
	}

	static void __init setup_processor(void)
	{
	struct cpu_info *cpu_info;

	/*
	* locate processor in the list of supported processor
	* types. The linker builds this table for us from the
	* entries in arch/arm/mm/proc.S
	*/
	cpu_info = lookup_processor_type(read_cpuid_id());
	if (!cpu_info) {
	printk("CPU configuration botched (ID %08x), unable to continue.\n",
	read_cpuid_id());
	while (1);
	}

	cpu_name = cpu_info->cpu_name;

	printk("CPU: %s [%08x] revision %d\n",
	cpu_name, read_cpuid_id(), read_cpuid_id() & 15);

	sprintf(init_utsname()->machine, "aarch64");
	elf_hwcap = 0;
	}

	static void __init setup_machine_fdt(phys_addr_t dt_phys)
	{
	struct boot_param_header *devtree;
	unsigned long dt_root;

	/* Check we have a non-NULL DT pointer */
	if (!dt_phys) {
	early_print("\n"
	"Error: NULL or invalid device tree blob\n"
	"The dtb must be 8-byte aligned and passed in the first 512MB of memory\n"
	"\nPlease check your bootloader.\n");

	while (true)
	cpu_relax();

	}

	devtree = phys_to_virt(dt_phys);

	/* Check device tree validity */
	if (be32_to_cpu(devtree->magic) != OF_DT_HEADER) {
	early_print("\n"
	"Error: invalid device tree blob at physical address 0x%p (virtual address 0x%p)\n"
	"Expected 0x%x, found 0x%x\n"
	"\nPlease check your bootloader.\n",
	dt_phys, devtree, OF_DT_HEADER,
	be32_to_cpu(devtree->magic));

	while (true)
	cpu_relax();
	}

	initial_boot_params = devtree;
	dt_root = of_get_flat_dt_root();

	machine_name = of_get_flat_dt_prop(dt_root, "model", NULL);
	if (!machine_name)
	machine_name = of_get_flat_dt_prop(dt_root, "compatible", NULL);
	if (!machine_name)
	machine_name = "<unknown>";
	pr_info("Machine: %s\n", machine_name);

	/* Retrieve various information from the /chosen node */
	of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
	/* Initialize {size,address}-cells info */
	of_scan_flat_dt(early_init_dt_scan_root, NULL);
	/* Setup memory, calling early_init_dt_add_memory_arch */
	of_scan_flat_dt(early_init_dt_scan_memory, NULL);
	}

	void __init early_init_dt_add_memory_arch(u64 base, u64 size)
	{
	base &= PAGE_MASK;
	size &= PAGE_MASK;
	if (base + size < PHYS_OFFSET) {
	pr_warning("Ignoring memory block 0x%llx - 0x%llx\n",
	base, base + size);
	return;
	}
	if (base < PHYS_OFFSET) {
	pr_warning("Ignoring memory range 0x%llx - 0x%llx\n",
	base, PHYS_OFFSET);
	size -= PHYS_OFFSET - base;
	base = PHYS_OFFSET;
	}
	memblock_add(base, size);
	}

	void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
	{
	return __va(memblock_alloc(size, align));
	}

	/*
	* Limit the memory size that was specified via FDT.
	*/
	static int __init early_mem(char *p)
	{
	phys_addr_t limit;

	if (!p)
	return 1;

	limit = memparse(p, &p) & PAGE_MASK;
	pr_notice("Memory limited to %lldMB\n", limit >> 20);

	memblock_enforce_memory_limit(limit);

	return 0;
	}
	early_param("mem", early_mem);

	static void __init request_standard_resources(void)
	{
	struct memblock_region *region;
	struct resource *res;

	kernel_code.start = virt_to_phys(_text);
	kernel_code.end = virt_to_phys(_etext - 1);
	kernel_data.start = virt_to_phys(_sdata);
	kernel_data.end = virt_to_phys(_end - 1);

	for_each_memblock(memory, region) {
	res = alloc_bootmem_low(sizeof(*res));
	res->name = "System RAM";
	res->start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
	res->end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
	res->flags = IORESOURCE_MEM \| IORESOURCE_BUSY;

	request_resource(&iomem_resource, res);

	if (kernel_code.start >= res->start &&
	kernel_code.end <= res->end)
	request_resource(res, &kernel_code);
	if (kernel_data.start >= res->start &&
	kernel_data.end <= res->end)
	request_resource(res, &kernel_data);
	}
	}

	void __init setup_arch(char **cmdline_p)
	{
	setup_processor();

	setup_machine_fdt(__fdt_pointer);

	init_mm.start_code = (unsigned long) _text;
	init_mm.end_code = (unsigned long) _etext;
	init_mm.end_data = (unsigned long) _edata;
	init_mm.brk = (unsigned long) _end;

	*cmdline_p = boot_command_line;

	parse_early_param();

	arm64_memblock_init();

	paging_init();
	request_standard_resources();

	unflatten_device_tree();

	#ifdef CONFIG_SMP
	smp_init_cpus();
	#endif

	#ifdef CONFIG_VT
	#if defined(CONFIG_VGA_CONSOLE)
	conswitchp = &vga_con;
	#elif defined(CONFIG_DUMMY_CONSOLE)
	conswitchp = &dummy_con;
	#endif
	#endif
	}

	static DEFINE_PER_CPU(struct cpu, cpu_data);

	static int __init topology_init(void)
	{
	int i;

	for_each_possible_cpu(i) {
	struct cpu *cpu = &per_cpu(cpu_data, i);
	cpu->hotpluggable = 1;
	register_cpu(cpu, i);
	}

	return 0;
	}
	subsys_initcall(topology_init);

	static const char *hwcap_str[] = {
	"fp",
	"asimd",
	NULL
	};

	static int c_show(struct seq_file m, void v)
	{
	int i;

	seq_printf(m, "Processor\t: %s rev %d (%s)\n",
	cpu_name, read_cpuid_id() & 15, ELF_PLATFORM);

	for_each_online_cpu(i) {
	/*
	* glibc reads /proc/cpuinfo to determine the number of
	* online processors, looking for lines beginning with
	* "processor". Give glibc what it expects.
	*/
	#ifdef CONFIG_SMP
	seq_printf(m, "processor\t: %d\n", i);
	#endif
	seq_printf(m, "BogoMIPS\t: %lu.%02lu\n\n",
	loops_per_jiffy / (500000UL/HZ),
	loops_per_jiffy / (5000UL/HZ) % 100);
	}

	/* dump out the processor features */
	seq_puts(m, "Features\t: ");

	for (i = 0; hwcap_str[i]; i++)
	if (elf_hwcap & (1 << i))
	seq_printf(m, "%s ", hwcap_str[i]);

	seq_printf(m, "\nCPU implementer\t: 0x%02x\n", read_cpuid_id() >> 24);
	seq_printf(m, "CPU architecture: AArch64\n");
	seq_printf(m, "CPU variant\t: 0x%x\n", (read_cpuid_id() >> 20) & 15);
	seq_printf(m, "CPU part\t: 0x%03x\n", (read_cpuid_id() >> 4) & 0xfff);
	seq_printf(m, "CPU revision\t: %d\n", read_cpuid_id() & 15);

	seq_puts(m, "\n");

	seq_printf(m, "Hardware\t: %s\n", machine_name);

	return 0;
	}

	static void c_start(struct seq_file m, loff_t *pos)
	{
	return pos < 1 ? (void )1 : NULL;
	}

	static void c_next(struct seq_file m, void v, loff_t pos)
	{
	++*pos;
	return NULL;
	}

	static void c_stop(struct seq_file m, void v)
	{
	}

	const struct seq_operations cpuinfo_op = {
	.start = c_start,
	.next = c_next,
	.stop = c_stop,
	.show = c_show
	};