#include <linux/irqchip/arm-gic-v3.h>
#include <asm/assembler.h>
+#include <asm/boot.h>
#include <asm/ptrace.h>
#include <asm/asm-offsets.h>
#include <asm/cache.h>
#include <asm/cputype.h>
+#include <asm/elf.h>
#include <asm/kernel-pgtable.h>
#include <asm/memory.h>
#include <asm/pgtable-hwdef.h>
#error TEXT_OFFSET must be less than 2MB
#endif
-#define KERNEL_START _text
-#define KERNEL_END _end
-
/*
* Kernel startup entry point.
* ---------------------------
* in the entry routines.
*/
__HEAD
-
+_head:
/*
* DO NOT MODIFY. Image header expected by Linux boot-loaders.
*/
#ifdef CONFIG_EFI
-efi_head:
/*
* This add instruction has no meaningful effect except that
* its opcode forms the magic "MZ" signature required by UEFI.
b stext // branch to kernel start, magic
.long 0 // reserved
#endif
- .quad _kernel_offset_le // Image load offset from start of RAM, little-endian
- .quad _kernel_size_le // Effective size of kernel image, little-endian
- .quad _kernel_flags_le // Informative flags, little-endian
+ le64sym _kernel_offset_le // Image load offset from start of RAM, little-endian
+ le64sym _kernel_size_le // Effective size of kernel image, little-endian
+ le64sym _kernel_flags_le // Informative flags, little-endian
.quad 0 // reserved
.quad 0 // reserved
.quad 0 // reserved
.byte 0x4d
.byte 0x64
#ifdef CONFIG_EFI
- .long pe_header - efi_head // Offset to the PE header.
+ .long pe_header - _head // Offset to the PE header.
#else
.word 0 // reserved
#endif
#ifdef CONFIG_EFI
- .globl __efistub_stext_offset
- .set __efistub_stext_offset, stext - efi_head
.align 3
pe_header:
.ascii "PE"
.short 0x20b // PE32+ format
.byte 0x02 // MajorLinkerVersion
.byte 0x14 // MinorLinkerVersion
- .long _end - stext // SizeOfCode
+ .long _end - efi_header_end // SizeOfCode
.long 0 // SizeOfInitializedData
.long 0 // SizeOfUninitializedData
- .long __efistub_entry - efi_head // AddressOfEntryPoint
- .long __efistub_stext_offset // BaseOfCode
+ .long __efistub_entry - _head // AddressOfEntryPoint
+ .long efi_header_end - _head // BaseOfCode
extra_header_fields:
.quad 0 // ImageBase
.short 0 // MinorSubsystemVersion
.long 0 // Win32VersionValue
- .long _end - efi_head // SizeOfImage
+ .long _end - _head // SizeOfImage
// Everything before the kernel image is considered part of the header
- .long __efistub_stext_offset // SizeOfHeaders
+ .long efi_header_end - _head // SizeOfHeaders
.long 0 // CheckSum
.short 0xa // Subsystem (EFI application)
.short 0 // DllCharacteristics
.byte 0
.byte 0
.byte 0 // end of 0 padding of section name
- .long _end - stext // VirtualSize
- .long __efistub_stext_offset // VirtualAddress
- .long _edata - stext // SizeOfRawData
- .long __efistub_stext_offset // PointerToRawData
+ .long _end - efi_header_end // VirtualSize
+ .long efi_header_end - _head // VirtualAddress
+ .long _edata - efi_header_end // SizeOfRawData
+ .long efi_header_end - _head // PointerToRawData
.long 0 // PointerToRelocations (0 for executables)
.long 0 // PointerToLineNumbers (0 for executables)
.long 0xe0500020 // Characteristics (section flags)
/*
- * EFI will load stext onwards at the 4k section alignment
+ * EFI will load .text onwards at the 4k section alignment
* described in the PE/COFF header. To ensure that instruction
* sequences using an adrp and a :lo12: immediate will function
- * correctly at this alignment, we must ensure that stext is
+ * correctly at this alignment, we must ensure that .text is
* placed at a 4k boundary in the Image to begin with.
*/
.align 12
+efi_header_end:
#endif
+ __INIT
+
ENTRY(stext)
bl preserve_boot_args
bl el2_setup // Drop to EL1, w20=cpu_boot_mode
adrp x24, __PHYS_OFFSET
+ and x23, x24, MIN_KIMG_ALIGN - 1 // KASLR offset, defaults to 0
bl set_cpu_boot_mode_flag
bl __create_page_tables // x25=TTBR0, x26=TTBR1
/*
* On return, the CPU will be ready for the MMU to be turned on and
* the TCR will have been set.
*/
- ldr x27, =__mmap_switched // address to jump to after
+ bl __cpu_setup // initialise processor
+ adr_l x27, __primary_switch // address to jump to after
// MMU has been enabled
- adr_l lr, __enable_mmu // return (PIC) address
- b __cpu_setup // initialise processor
+ b __enable_mmu
ENDPROC(stext)
/*
__create_page_tables:
adrp x25, idmap_pg_dir
adrp x26, swapper_pg_dir
- mov x27, lr
+ mov x28, lr
/*
* Invalidate the idmap and swapper page tables to avoid potential
cmp x0, x6
b.lo 1b
- ldr x7, =SWAPPER_MM_MMUFLAGS
+ mov x7, SWAPPER_MM_MMUFLAGS
/*
* Create the identity mapping.
* Map the kernel image (starting with PHYS_OFFSET).
*/
mov x0, x26 // swapper_pg_dir
- mov x5, #PAGE_OFFSET
+ mov_q x5, KIMAGE_VADDR + TEXT_OFFSET // compile time __va(_text)
+ add x5, x5, x23 // add KASLR displacement
create_pgd_entry x0, x5, x3, x6
- ldr x6, =KERNEL_END // __va(KERNEL_END)
- mov x3, x24 // phys offset
+ adrp x6, _end // runtime __pa(_end)
+ adrp x3, _text // runtime __pa(_text)
+ sub x6, x6, x3 // _end - _text
+ add x6, x6, x5 // runtime __va(_end)
create_block_map x0, x7, x3, x5, x6
/*
dmb sy
bl __inval_cache_range
- mov lr, x27
- ret
+ ret x28
ENDPROC(__create_page_tables)
.ltorg
* The following fragment of code is executed with the MMU enabled.
*/
.set initial_sp, init_thread_union + THREAD_START_SP
-__mmap_switched:
- adr_l x6, __bss_start
- adr_l x7, __bss_stop
-
-1: cmp x6, x7
- b.hs 2f
- str xzr, [x6], #8 // Clear BSS
- b 1b
-2:
+__primary_switched:
+ mov x28, lr // preserve LR
+ adr_l x8, vectors // load VBAR_EL1 with virtual
+ msr vbar_el1, x8 // vector table address
+ isb
+
+ // Clear BSS
+ adr_l x0, __bss_start
+ mov x1, xzr
+ adr_l x2, __bss_stop
+ sub x2, x2, x0
+ bl __pi_memset
+ dsb ishst // Make zero page visible to PTW
+
adr_l sp, initial_sp, x4
+ mov x4, sp
+ and x4, x4, #~(THREAD_SIZE - 1)
+ msr sp_el0, x4 // Save thread_info
str_l x21, __fdt_pointer, x5 // Save FDT pointer
- str_l x24, memstart_addr, x6 // Save PHYS_OFFSET
+
+ ldr_l x4, kimage_vaddr // Save the offset between
+ sub x4, x4, x24 // the kernel virtual and
+ str_l x4, kimage_voffset, x5 // physical mappings
+
mov x29, #0
#ifdef CONFIG_KASAN
bl kasan_early_init
+#endif
+#ifdef CONFIG_RANDOMIZE_BASE
+ tst x23, ~(MIN_KIMG_ALIGN - 1) // already running randomized?
+ b.ne 0f
+ mov x0, x21 // pass FDT address in x0
+ mov x1, x23 // pass modulo offset in x1
+ bl kaslr_early_init // parse FDT for KASLR options
+ cbz x0, 0f // KASLR disabled? just proceed
+ orr x23, x23, x0 // record KASLR offset
+ ret x28 // we must enable KASLR, return
+ // to __enable_mmu()
+0:
#endif
b start_kernel
-ENDPROC(__mmap_switched)
+ENDPROC(__primary_switched)
/*
* end early head section, begin head code that is also used for
* hotplug and needs to have the same protections as the text region
*/
.section ".text","ax"
+
+ENTRY(kimage_vaddr)
+ .quad _text - TEXT_OFFSET
+
/*
* If we're fortunate enough to boot at EL2, ensure that the world is
* sane before dropping to EL1.
#endif
/* EL2 debug */
+ mrs x0, id_aa64dfr0_el1 // Check ID_AA64DFR0_EL1 PMUVer
+ sbfx x0, x0, #8, #4
+ cmp x0, #1
+ b.lt 4f // Skip if no PMU present
mrs x0, pmcr_el0 // Disable debug access traps
ubfx x0, x0, #11, #5 // to EL2 and allow access to
- msr mdcr_el2, x0 // all PMU counters from EL1
+4:
+ csel x0, xzr, x0, lt // all PMU counters from EL1
+ msr mdcr_el2, x0 // (if they exist)
/* Stage-2 translation */
msr vttbr_el2, xzr
* Sets the __boot_cpu_mode flag depending on the CPU boot mode passed
* in x20. See arch/arm64/include/asm/virt.h for more info.
*/
-ENTRY(set_cpu_boot_mode_flag)
+set_cpu_boot_mode_flag:
adr_l x1, __boot_cpu_mode
cmp w20, #BOOT_CPU_MODE_EL2
b.ne 1f
bl el2_setup // Drop to EL1, w20=cpu_boot_mode
bl set_cpu_boot_mode_flag
mrs x0, mpidr_el1
- ldr x1, =MPIDR_HWID_BITMASK
+ mov_q x1, MPIDR_HWID_BITMASK
and x0, x0, x1
adr_l x3, secondary_holding_pen_release
pen: ldr x4, [x3]
b secondary_startup
ENDPROC(secondary_entry)
-ENTRY(secondary_startup)
+secondary_startup:
/*
* Common entry point for secondary CPUs.
*/
adrp x26, swapper_pg_dir
bl __cpu_setup // initialise processor
- ldr x21, =secondary_data
- ldr x27, =__secondary_switched // address to jump to after enabling the MMU
+ adr_l x27, __secondary_switch // address to jump to after enabling the MMU
b __enable_mmu
ENDPROC(secondary_startup)
-ENTRY(__secondary_switched)
- ldr x0, [x21] // get secondary_data.stack
+__secondary_switched:
+ adr_l x5, vectors
+ msr vbar_el1, x5
+ isb
+
+ ldr_l x0, secondary_data // get secondary_data.stack
mov sp, x0
+ and x0, x0, #~(THREAD_SIZE - 1)
+ msr sp_el0, x0 // save thread_info
mov x29, #0
b secondary_start_kernel
ENDPROC(__secondary_switched)
* If it isn't, park the CPU
*/
.section ".idmap.text", "ax"
-__enable_mmu:
+ENTRY(__enable_mmu)
+ mrs x18, sctlr_el1 // preserve old SCTLR_EL1 value
mrs x1, ID_AA64MMFR0_EL1
ubfx x2, x1, #ID_AA64MMFR0_TGRAN_SHIFT, 4
cmp x2, #ID_AA64MMFR0_TGRAN_SUPPORTED
b.ne __no_granule_support
- ldr x5, =vectors
- msr vbar_el1, x5
msr ttbr0_el1, x25 // load TTBR0
msr ttbr1_el1, x26 // load TTBR1
isb
ic iallu
dsb nsh
isb
+#ifdef CONFIG_RANDOMIZE_BASE
+ mov x19, x0 // preserve new SCTLR_EL1 value
+ blr x27
+
+ /*
+ * If we return here, we have a KASLR displacement in x23 which we need
+ * to take into account by discarding the current kernel mapping and
+ * creating a new one.
+ */
+ msr sctlr_el1, x18 // disable the MMU
+ isb
+ bl __create_page_tables // recreate kernel mapping
+
+ msr sctlr_el1, x19 // re-enable the MMU
+ isb
+ ic iallu // flush instructions fetched
+ dsb nsh // via old mapping
+ isb
+#endif
br x27
ENDPROC(__enable_mmu)
wfe
b __no_granule_support
ENDPROC(__no_granule_support)
+
+__primary_switch:
+#ifdef CONFIG_RELOCATABLE
+ /*
+ * Iterate over each entry in the relocation table, and apply the
+ * relocations in place.
+ */
+ ldr w9, =__rela_offset // offset to reloc table
+ ldr w10, =__rela_size // size of reloc table
+
+ mov_q x11, KIMAGE_VADDR // default virtual offset
+ add x11, x11, x23 // actual virtual offset
+ add x9, x9, x11 // __va(.rela)
+ add x10, x9, x10 // __va(.rela) + sizeof(.rela)
+
+0: cmp x9, x10
+ b.hs 1f
+ ldp x11, x12, [x9], #24
+ ldr x13, [x9, #-8]
+ cmp w12, #R_AARCH64_RELATIVE
+ b.ne 0b
+ add x13, x13, x23 // relocate
+ str x13, [x11, x23]
+ b 0b
+
+1:
+#endif
+ ldr x8, =__primary_switched
+ br x8
+ENDPROC(__primary_switch)
+
+__secondary_switch:
+ ldr x8, =__secondary_switched
+ br x8
+ENDPROC(__secondary_switch)