- 根目录:
- arch
- arm64
- kernel
- setup.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/acpi.h>
#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/cache.h>
#include <linux/bootmem.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_iommu.h>
#include <linux/of_fdt.h>
#include <linux/of_platform.h>
#include <linux/efi.h>
#include <linux/psci.h>
#include <asm/acpi.h>
#include <asm/fixmap.h>
#include <asm/cpu.h>
#include <asm/cputype.h>
#include <asm/elf.h>
#include <asm/cpufeature.h>
#include <asm/cpu_ops.h>
#include <asm/kasan.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/efi.h>
#include <asm/xen/hypervisor.h>
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]
/*
* The recorded values of x0 .. x3 upon kernel entry.
*/
u64 __cacheline_aligned boot_args[4];
void __init smp_setup_processor_id(void)
{
u64 mpidr = read_cpuid_mpidr() & MPIDR_HWID_BITMASK;
cpu_logical_map(0) = mpidr;
/*
* clear __my_cpu_offset on boot CPU to avoid hang caused by
* using percpu variable early, for example, lockdep will
* access percpu variable inside lock_release
*/
set_my_cpu_offset(0);
pr_info("Booting Linux on physical CPU 0x%lx\n", (unsigned long)mpidr);
}
bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
{
return phys_id == cpu_logical_map(cpu);
}
struct mpidr_hash mpidr_hash;
/**
* smp_build_mpidr_hash - Pre-compute shifts required at each affinity
* level in order to build a linear index from an
* MPIDR value. Resulting algorithm is a collision
* free hash carried out through shifting and ORing
*/
static void __init smp_build_mpidr_hash(void)
{
u32 i, affinity, fs[4], bits[4], ls;
u64 mask = 0;
/*
* Pre-scan the list of MPIDRS and filter out bits that do
* not contribute to affinity levels, ie they never toggle.
*/
for_each_possible_cpu(i)
mask |= (cpu_logical_map(i) ^ cpu_logical_map(0));
pr_debug("mask of set bits %#llx\n", mask);
/*
* Find and stash the last and first bit set at all affinity levels to
* check how many bits are required to represent them.
*/
for (i = 0; i < 4; i++) {
affinity = MPIDR_AFFINITY_LEVEL(mask, i);
/*
* Find the MSB bit and LSB bits position
* to determine how many bits are required
* to express the affinity level.
*/
ls = fls(affinity);
fs[i] = affinity ? ffs(affinity) - 1 : 0;
bits[i] = ls - fs[i];
}
/*
* An index can be created from the MPIDR_EL1 by isolating the
* significant bits at each affinity level and by shifting
* them in order to compress the 32 bits values space to a
* compressed set of values. This is equivalent to hashing
* the MPIDR_EL1 through shifting and ORing. It is a collision free
* hash though not minimal since some levels might contain a number
* of CPUs that is not an exact power of 2 and their bit
* representation might contain holes, eg MPIDR_EL1[7:0] = {0x2, 0x80}.
*/
mpidr_hash.shift_aff[0] = MPIDR_LEVEL_SHIFT(0) + fs[0];
mpidr_hash.shift_aff[1] = MPIDR_LEVEL_SHIFT(1) + fs[1] - bits[0];
mpidr_hash.shift_aff[2] = MPIDR_LEVEL_SHIFT(2) + fs[2] -
(bits[1] + bits[0]);
mpidr_hash.shift_aff[3] = MPIDR_LEVEL_SHIFT(3) +
fs[3] - (bits[2] + bits[1] + bits[0]);
mpidr_hash.mask = mask;
mpidr_hash.bits = bits[3] + bits[2] + bits[1] + bits[0];
pr_debug("MPIDR hash: aff0[%u] aff1[%u] aff2[%u] aff3[%u] mask[%#llx] bits[%u]\n",
mpidr_hash.shift_aff[0],
mpidr_hash.shift_aff[1],
mpidr_hash.shift_aff[2],
mpidr_hash.shift_aff[3],
mpidr_hash.mask,
mpidr_hash.bits);
/*
* 4x is an arbitrary value used to warn on a hash table much bigger
* than expected on most systems.
*/
if (mpidr_hash_size() > 4 * num_possible_cpus())
pr_warn("Large number of MPIDR hash buckets detected\n");
__flush_dcache_area(&mpidr_hash, sizeof(struct mpidr_hash));
}
static void __init setup_machine_fdt(phys_addr_t dt_phys)
{
void *dt_virt = fixmap_remap_fdt(dt_phys);
if (!dt_virt || !early_init_dt_scan(dt_virt)) {
pr_crit("\n"
"Error: invalid device tree blob at physical address %pa (virtual address 0x%p)\n"
"The dtb must be 8-byte aligned and must not exceed 2 MB in size\n"
"\nPlease check your bootloader.",
&dt_phys, dt_virt);
while (true)
cpu_relax();
}
dump_stack_set_arch_desc("%s (DT)", of_flat_dt_get_machine_name());
}
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);
}
}
#ifdef CONFIG_BLK_DEV_INITRD
/*
* Relocate initrd if it is not completely within the linear mapping.
* This would be the case if mem= cuts out all or part of it.
*/
static void __init relocate_initrd(void)
{
phys_addr_t orig_start = __virt_to_phys(initrd_start);
phys_addr_t orig_end = __virt_to_phys(initrd_end);
phys_addr_t ram_end = memblock_end_of_DRAM();
phys_addr_t new_start;
unsigned long size, to_free = 0;
void *dest;
if (orig_end <= ram_end)
return;
/*
* Any of the original initrd which overlaps the linear map should
* be freed after relocating.
*/
if (orig_start < ram_end)
to_free = ram_end - orig_start;
size = orig_end - orig_start;
if (!size)
return;
/* initrd needs to be relocated completely inside linear mapping */
new_start = memblock_find_in_range(0, PFN_PHYS(max_pfn),
size, PAGE_SIZE);
if (!new_start)
panic("Cannot relocate initrd of size %ld\n", size);
memblock_reserve(new_start, size);
initrd_start = __phys_to_virt(new_start);
initrd_end = initrd_start + size;
pr_info("Moving initrd from [%llx-%llx] to [%llx-%llx]\n",
orig_start, orig_start + size - 1,
new_start, new_start + size - 1);
dest = (void *)initrd_start;
if (to_free) {
memcpy(dest, (void *)__phys_to_virt(orig_start), to_free);
dest += to_free;
}
copy_from_early_mem(dest, orig_start + to_free, size - to_free);
if (to_free) {
pr_info("Freeing original RAMDISK from [%llx-%llx]\n",
orig_start, orig_start + to_free - 1);
memblock_free(orig_start, to_free);
}
}
#else
static inline void __init relocate_initrd(void)
{
}
#endif
u64 __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = INVALID_HWID };
void __init setup_arch(char **cmdline_p)
{
pr_info("Boot CPU: AArch64 Processor [%08x]\n", read_cpuid_id());
sprintf(init_utsname()->machine, ELF_PLATFORM);
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;
early_fixmap_init();
early_ioremap_init();
setup_machine_fdt(__fdt_pointer);
parse_early_param();
/*
* Unmask asynchronous aborts after bringing up possible earlycon.
* (Report possible System Errors once we can report this occurred)
*/
local_async_enable();
efi_init();
arm64_memblock_init();
/* Parse the ACPI tables for possible boot-time configuration */
acpi_boot_table_init();
paging_init();
relocate_initrd();
kasan_init();
request_standard_resources();
early_ioremap_reset();
if (acpi_disabled) {
unflatten_device_tree();
psci_dt_init();
} else {
psci_acpi_init();
}
xen_early_init();
cpu_read_bootcpu_ops();
smp_init_cpus();
smp_build_mpidr_hash();
#ifdef CONFIG_VT
#if defined(CONFIG_VGA_CONSOLE)
conswitchp = &vga_con;
#elif defined(CONFIG_DUMMY_CONSOLE)
conswitchp = &dummy_con;
#endif
#endif
if (boot_args[1] || boot_args[2] || boot_args[3]) {
pr_err("WARNING: x1-x3 nonzero in violation of boot protocol:\n"
"\tx1: %016llx\n\tx2: %016llx\n\tx3: %016llx\n"
"This indicates a broken bootloader or old kernel\n",
boot_args[1], boot_args[2], boot_args[3]);
}
}
static int __init arm64_device_init(void)
{
if (of_have_populated_dt()) {
of_iommu_init();
of_platform_populate(NULL, of_default_bus_match_table,
NULL, NULL);
} else if (acpi_disabled) {
pr_crit("Device tree not populated\n");
}
return 0;
}
arch_initcall_sync(arm64_device_init);
static int __init topology_init(void)
{
int i;
for_each_possible_cpu(i) {
struct cpu *cpu = &per_cpu(cpu_data.cpu, i);
cpu->hotpluggable = 1;
register_cpu(cpu, i);
}
return 0;
}
subsys_initcall(topology_init);