kernel_optimize_test/arch/arm64/kernel/setup.c
Mark Rutland e8765b265a arm64: read enable-method for CPU0
With the advent of CPU_HOTPLUG, the enable-method property for CPU0 may
tells us something useful (i.e. how to hotplug it back on), so we must
read it along with all the enable-method for all the other CPUs.  Even
on UP the enable-method may tell us useful information (e.g. if a core
has some mechanism that might be usable for cpuidle), so we should
always read it.

This patch factors out the reading of the enable method, and ensures
that CPU0's enable method is read regardless of whether the kernel is
built with SMP support.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2013-10-25 11:33:20 +01:00

371 lines
8.5 KiB
C

/*
* 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/clk-provider.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 <linux/of_platform.h>
#include <asm/cputype.h>
#include <asm/elf.h>
#include <asm/cputable.h>
#include <asm/cpu_ops.h>
#include <asm/sections.h>
#include <asm/setup.h>
#include <asm/smp_plat.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>
#include <asm/traps.h>
#include <asm/memblock.h>
#include <asm/psci.h>
unsigned int processor_id;
EXPORT_SYMBOL(processor_id);
unsigned long 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);
}
/*
* 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);
}
}
u64 __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = INVALID_HWID };
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();
psci_init();
cpu_logical_map(0) = read_cpuid_mpidr() & MPIDR_HWID_BITMASK;
cpu_read_bootcpu_ops();
#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 int __init arm64_device_init(void)
{
of_clk_init(NULL);
of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
return 0;
}
arch_initcall(arm64_device_init);
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
}
/* 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
};