1
0
Fork 0
mirror of https://github.com/Atmosphere-NX/Atmosphere.git synced 2024-11-15 00:16:48 +00:00
Atmosphere/mesosphere/kernel/source/arch/arm64/init/start.s
2020-04-18 22:19:09 -07:00

472 lines
15 KiB
ArmAsm

/*
* Copyright (c) 2018-2020 Atmosphère-NX
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope 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/>.
*/
/* For some reason GAS doesn't know about it, even with .cpu cortex-a57 */
#define cpuactlr_el1 s3_1_c15_c2_0
#define cpuectlr_el1 s3_1_c15_c2_1
#define LOAD_IMMEDIATE_32(reg, val) \
mov reg, #(((val) >> 0x00) & 0xFFFF); \
movk reg, #(((val) >> 0x10) & 0xFFFF), lsl#16
#define LOAD_IMMEDIATE_64(reg, val) \
mov reg, #(((val) >> 0x00) & 0xFFFF); \
movk reg, #(((val) >> 0x10) & 0xFFFF), lsl#16; \
movk reg, #(((val) >> 0x20) & 0xFFFF), lsl#32; \
movk reg, #(((val) >> 0x30) & 0xFFFF), lsl#48
#define LOAD_FROM_LABEL(reg, label) \
adr reg, label; \
ldr reg, [reg]
.section .crt0.text.start, "ax", %progbits
.global _start
_start:
b _ZN3ams4kern4init10StartCore0Emm
__metadata_begin:
.ascii "MSS0" /* Magic */
__metadata_ini_offset:
.quad 0 /* INI1 base address. */
__metadata_kernelldr_offset:
.quad 0 /* Kernel Loader base address. */
__metadata_target_firmware:
.word 0xCCCCCCCC /* Target firmware. */
__metadata_kernel_layout:
.word _start - _start /* rx_offset */
.word __rodata_start - _start /* rx_end_offset */
.word __rodata_start - _start /* ro_offset */
.word __data_start - _start /* ro_end_offset */
.word __data_start - _start /* rw_offset */
.word __bss_start__ - _start /* rw_end_offset */
.word __bss_start__ - _start /* bss_offset */
.word __bss_end__ - _start /* bss_end_offset */
.word __end__ - _start /* ini_load_offset */
.word _DYNAMIC - _start /* dynamic_offset */
.word __init_array_start - _start /* init_array_offset */
.word __init_array_end - _start /* init_array_end_offset */
.if (. - __metadata_begin) != 0x48
.error "Incorrect Mesosphere Metadata"
.endif
.global _ZN3ams4kern17GetTargetFirmwareEv
.type _ZN3ams4kern17GetTargetFirmwareEv, %function
_ZN3ams4kern17GetTargetFirmwareEv:
adr x0, __metadata_target_firmware
ldr w0, [x0]
ret
/* ams::kern::init::StartCore0(uintptr_t, uintptr_t) */
.section .crt0.text._ZN3ams4kern4init10StartCore0Emm, "ax", %progbits
.global _ZN3ams4kern4init10StartCore0Emm
.type _ZN3ams4kern4init10StartCore0Emm, %function
_ZN3ams4kern4init10StartCore0Emm:
/* Mask all interrupts. */
msr daifset, #0xF
/* Save arguments for later use. */
mov x19, x0
mov x20, x1
/* Check our current EL. We want to be executing out of EL1. */
/* If we're in EL2, we'll need to deprivilege ourselves. */
mrs x1, currentel
cmp x1, #0x4
b.eq core0_el1
cmp x1, #0x8
b.eq core0_el2
core0_el3:
b core0_el3
core0_el2:
bl _ZN3ams4kern4init16JumpFromEL2ToEL1Ev
core0_el1:
bl _ZN3ams4kern4init19DisableMmuAndCachesEv
/* We want to invoke kernel loader. */
adr x0, _start
adr x1, __metadata_kernel_layout
LOAD_FROM_LABEL(x2, __metadata_ini_offset)
add x2, x0, x2
LOAD_FROM_LABEL(x3, __metadata_kernelldr_offset)
add x3, x0, x3
/* If kernelldr is ours, set its target firmware. */
ldr w4, [x3, #4]
LOAD_IMMEDIATE_32(w5, 0x30444C4D)
cmp w4, w5
b.ne 1f
LOAD_FROM_LABEL(x4, __metadata_target_firmware)
str w4, [x3, #8]
1:
blr x3
/* At this point kernelldr has been invoked, and we are relocated at a random virtual address. */
/* Next thing to do is to set up our memory management and slabheaps -- all the other core initialization. */
/* Call ams::kern::init::InitializeCore(uintptr_t, uintptr_t) */
mov x1, x0 /* Kernelldr returns a KInitialPageAllocator state for the kernel to re-use. */
mov x0, xzr /* Official kernel always passes zero, when this is non-zero the address is mapped. */
bl _ZN3ams4kern4init14InitializeCoreEmm
/* Get the init arguments for core 0. */
mov x0, xzr
bl _ZN3ams4kern4init23GetInitArgumentsAddressEi
bl _ZN3ams4kern4init16InvokeEntrypointEPKNS1_14KInitArgumentsE
/* ams::kern::init::StartOtherCore(const ams::kern::init::KInitArguments *) */
.section .crt0.text._ZN3ams4kern4init14StartOtherCoreEPKNS1_14KInitArgumentsE, "ax", %progbits
.global _ZN3ams4kern4init14StartOtherCoreEPKNS1_14KInitArgumentsE
.type _ZN3ams4kern4init14StartOtherCoreEPKNS1_14KInitArgumentsE, %function
_ZN3ams4kern4init14StartOtherCoreEPKNS1_14KInitArgumentsE:
/* Preserve the KInitArguments pointer in a register. */
mov x20, x0
/* Check our current EL. We want to be executing out of EL1. */
/* If we're in EL2, we'll need to deprivilege ourselves. */
mrs x1, currentel
cmp x1, #0x4
b.eq othercore_el1
cmp x1, #0x8
b.eq othercore_el2
othercore_el3:
b othercore_el3
othercore_el2:
bl _ZN3ams4kern4init16JumpFromEL2ToEL1Ev
othercore_el1:
bl _ZN3ams4kern4init19DisableMmuAndCachesEv
/* Setup system registers using values from our KInitArguments. */
ldr x1, [x20, #0x00]
msr ttbr0_el1, x1
ldr x1, [x20, #0x08]
msr ttbr1_el1, x1
ldr x1, [x20, #0x10]
msr tcr_el1, x1
ldr x1, [x20, #0x18]
msr mair_el1, x1
/* Perform cpu-specific setup. */
mrs x1, midr_el1
ubfx x2, x1, #0x18, #0x8 /* Extract implementer bits. */
cmp x2, #0x41 /* Implementer::ArmLimited */
b.ne othercore_cpu_specific_setup_end
ubfx x2, x1, #0x4, #0xC /* Extract primary part number. */
cmp x2, #0xD07 /* PrimaryPartNumber::CortexA57 */
b.eq othercore_cpu_specific_setup_cortex_a57
cmp x2, #0xD03 /* PrimaryPartNumber::CortexA53 */
b.eq othercore_cpu_specific_setup_cortex_a53
b othercore_cpu_specific_setup_end
othercore_cpu_specific_setup_cortex_a57:
othercore_cpu_specific_setup_cortex_a53:
ldr x1, [x20, #0x20]
msr cpuactlr_el1, x1
ldr x1, [x20, #0x28]
msr cpuectlr_el1, x1
othercore_cpu_specific_setup_end:
/* Ensure instruction consistency. */
dsb sy
isb
/* Set sctlr_el1 and ensure instruction consistency. */
ldr x1, [x20, #0x30]
msr sctlr_el1, x1
dsb sy
isb
/* Jump to the virtual address equivalent to ams::kern::init::InvokeEntrypoint */
ldr x1, [x20, #0x50]
adr x2, _ZN3ams4kern4init14StartOtherCoreEPKNS1_14KInitArgumentsE
sub x1, x1, x2
adr x2, _ZN3ams4kern4init16InvokeEntrypointEPKNS1_14KInitArgumentsE
add x1, x1, x2
mov x0, x20
br x1
/* ams::kern::init::InvokeEntrypoint(const ams::kern::init::KInitArguments *) */
.section .crt0.text._ZN3ams4kern4init16InvokeEntrypointEPKNS1_14KInitArgumentsE, "ax", %progbits
.global _ZN3ams4kern4init16InvokeEntrypointEPKNS1_14KInitArgumentsE
.type _ZN3ams4kern4init16InvokeEntrypointEPKNS1_14KInitArgumentsE, %function
_ZN3ams4kern4init16InvokeEntrypointEPKNS1_14KInitArgumentsE:
/* Preserve the KInitArguments pointer in a register. */
mov x20, x0
/* Clear CPACR_EL1. This will prevent classes of traps (SVE, etc). */
msr cpacr_el1, xzr
isb
/* Setup the stack pointer. */
ldr x1, [x20, #0x38]
mov sp, x1
/* Ensure that system debug registers are setup. */
bl _ZN3ams4kern4init24InitializeDebugRegistersEv
/* Ensure that the exception vectors are setup. */
bl _ZN3ams4kern4init26InitializeExceptionVectorsEv
/* Jump to the entrypoint. */
ldr x1, [x20, #0x40]
ldr x0, [x20, #0x48]
br x1
/* ams::kern::init::JumpFromEL2ToEL1() */
.section .crt0.text._ZN3ams4kern4init16JumpFromEL2ToEL1Ev, "ax", %progbits
.global _ZN3ams4kern4init16JumpFromEL2ToEL1Ev
.type _ZN3ams4kern4init16JumpFromEL2ToEL1Ev, %function
_ZN3ams4kern4init16JumpFromEL2ToEL1Ev:
/* We're going to want to ERET to our caller. */
msr elr_el2, x30
/* Flush the entire data cache and invalidate the entire TLB. */
bl _ZN3ams4kern4arch5arm643cpu32FlushEntireDataCacheWithoutStackEv
/* Setup system registers for deprivileging. */
/* ACTLR_EL2: */
/* - CPUACTLR access control = 1 */
/* - CPUECTLR access control = 1 */
/* - L2CTLR access control = 1 */
/* - L2ECTLR access control = 1 */
/* - L2ACTLR access control = 1 */
mov x0, #0x73
msr actlr_el2, x0
/* HCR_EL2: */
/* - RW = 1 (el1 is aarch64) */
mov x0, #0x80000000
msr hcr_el2, x0
/* SCTLR_EL1: */
/* - EOS = 1 */
/* - EIS = 1 */
/* - SPAN = 1 */
LOAD_IMMEDIATE_32(x0, 0x00C00800)
msr sctlr_el1, x0
/* DACR32_EL2: */
/* - Manager access for all D<n> */
mov x0, #0xFFFFFFFF
msr dacr32_el2, x0
/* SPSR_EL2: */
/* - EL1h */
/* - IRQ masked */
/* - FIQ masked */
mov x0, #0xC5
msr spsr_el2, x0
eret
/* ams::kern::init::DisableMmuAndCaches() */
.section .crt0.text._ZN3ams4kern4init19DisableMmuAndCachesEv, "ax", %progbits
.global _ZN3ams4kern4init19DisableMmuAndCachesEv
.type _ZN3ams4kern4init19DisableMmuAndCachesEv, %function
_ZN3ams4kern4init19DisableMmuAndCachesEv:
/* The stack isn't set up, so we'll need to trash a register. */
mov x22, x30
/* Flush the entire data cache and invalidate the entire TLB. */
bl _ZN3ams4kern4arch5arm643cpu32FlushEntireDataCacheWithoutStackEv
/* Invalidate the instruction cache, and ensure instruction consistency. */
ic ialluis
dsb sy
isb
/* Set SCTLR_EL1 to disable the caches and mmu. */
/* SCTLR_EL1: */
/* - M = 0 */
/* - C = 0 */
/* - I = 0 */
mrs x0, sctlr_el1
LOAD_IMMEDIATE_64(x1, ~0x1005)
and x0, x0, x1
msr sctlr_el1, x0
mov x30, x22
ret
/* ams::kern::arch::arm64::cpu::FlushEntireDataCacheWithoutStack() */
.section .crt0.text._ZN3ams4kern4arch5arm643cpu32FlushEntireDataCacheWithoutStackEv, "ax", %progbits
.global _ZN3ams4kern4arch5arm643cpu32FlushEntireDataCacheWithoutStackEv
.type _ZN3ams4kern4arch5arm643cpu32FlushEntireDataCacheWithoutStackEv, %function
_ZN3ams4kern4arch5arm643cpu32FlushEntireDataCacheWithoutStackEv:
/* The stack isn't set up, so we'll need to trash a register. */
mov x23, x30
/* Ensure that the cache is coherent. */
bl _ZN3ams4kern4arch5arm643cpu37FlushEntireDataCacheLocalWithoutStackEv
dsb sy
bl _ZN3ams4kern4arch5arm643cpu38FlushEntireDataCacheSharedWithoutStackEv
dsb sy
bl _ZN3ams4kern4arch5arm643cpu37FlushEntireDataCacheLocalWithoutStackEv
dsb sy
/* Invalidate the entire TLB, and ensure instruction consistency. */
tlbi vmalle1is
dsb sy
isb
mov x30, x23
ret
/* ams::kern::arch::arm64::cpu::FlushEntireDataCacheLocalWithoutStack() */
.section .crt0.text._ZN3ams4kern4arch5arm643cpu37FlushEntireDataCacheLocalWithoutStackEv, "ax", %progbits
.global _ZN3ams4kern4arch5arm643cpu37FlushEntireDataCacheLocalWithoutStackEv
.type _ZN3ams4kern4arch5arm643cpu37FlushEntireDataCacheLocalWithoutStackEv, %function
_ZN3ams4kern4arch5arm643cpu37FlushEntireDataCacheLocalWithoutStackEv:
/* The stack isn't set up, so we'll need to trash a register. */
mov x24, x30
/* CacheLineIdAccessor clidr_el1; */
mrs x10, clidr_el1
/* const int levels_of_unification = clidr_el1.GetLevelsOfUnification(); */
ubfx x10, x10, #0x15, 3
/* int level = levels_of_unification - 1 */
sub w9, w10, #1
/* while (level >= 0) { */
begin_flush_cache_local_loop:
cmn w9, #1
b.eq done_flush_cache_local_loop
/* FlushEntireDataCacheImplWithoutStack(level); */
mov w0, w9
bl _ZN3ams4kern4arch5arm643cpu36FlushEntireDataCacheImplWithoutStackEv
/* level--; */
sub w9, w9, #1
/* } */
b begin_flush_cache_local_loop
done_flush_cache_local_loop:
mov x30, x24
ret
/* ams::kern::arch::arm64::cpu::FlushEntireDataCacheSharedWithoutStack() */
.section .crt0.text._ZN3ams4kern4arch5arm643cpu38FlushEntireDataCacheSharedWithoutStackEv, "ax", %progbits
.global _ZN3ams4kern4arch5arm643cpu38FlushEntireDataCacheSharedWithoutStackEv
.type _ZN3ams4kern4arch5arm643cpu38FlushEntireDataCacheSharedWithoutStackEv, %function
_ZN3ams4kern4arch5arm643cpu38FlushEntireDataCacheSharedWithoutStackEv:
/* The stack isn't set up, so we'll need to trash a register. */
mov x24, x30
/* CacheLineIdAccessor clidr_el1; */
mrs x10, clidr_el1
/* const int levels_of_coherency = clidr_el1.GetLevelsOfCoherency(); */
ubfx x9, x10, #0x18, 3
/* const int levels_of_unification = clidr_el1.GetLevelsOfUnification(); */
ubfx x10, x10, #0x15, 3
/* int level = levels_of_coherency */
/* while (level >= levels_of_unification) { */
begin_flush_cache_shared_loop:
cmp w10, w9
b.gt done_flush_cache_shared_loop
/* FlushEntireDataCacheImplWithoutStack(level); */
mov w0, w9
bl _ZN3ams4kern4arch5arm643cpu36FlushEntireDataCacheImplWithoutStackEv
/* level--; */
sub w9, w9, #1
/* } */
b begin_flush_cache_shared_loop
done_flush_cache_shared_loop:
mov x30, x24
ret
/* ams::kern::arch::arm64::cpu::FlushEntireDataCacheImplWithoutStack() */
.section .crt0.text._ZN3ams4kern4arch5arm643cpu36FlushEntireDataCacheImplWithoutStackEv, "ax", %progbits
.global _ZN3ams4kern4arch5arm643cpu36FlushEntireDataCacheImplWithoutStackEv
.type _ZN3ams4kern4arch5arm643cpu36FlushEntireDataCacheImplWithoutStackEv, %function
_ZN3ams4kern4arch5arm643cpu36FlushEntireDataCacheImplWithoutStackEv:
/* const u64 level_sel_value = static_cast<u64>(level << 1); */
lsl w6, w0, #1
sxtw x6, w6
/* cpu::SetCsselrEl1(level_sel_value); */
msr csselr_el1, x6
/* cpu::InstructionMemoryBarrier(); */
isb
/* CacheSizeIdAccessor ccsidr_el1; */
mrs x3, ccsidr_el1
/* const int num_ways = ccsidr_el1.GetAssociativity(); */
ubfx x7, x3, #3, #0xA
mov w8, w7
/* const int line_size = ccsidr_el1.GetLineSize(); */
and x4, x3, #7
/* const u64 way_shift = static_cast<u64>(__builtin_clz(num_ways)); */
clz w7, w7
/* const u64 set_shift = static_cast<u64>(line_size + 4); */
add w4, w4, #4
/* const int num_sets = ccsidr_el1.GetNumberOfSets(); */
ubfx w3, w3, #0xD, #0xF
/* int way = 0; */
mov x5, #0
/* while (way <= num_ways) { */
begin_flush_cache_impl_way_loop:
cmp w8, w5
b.lt done_flush_cache_impl_way_loop
/* int set = 0; */
mov x0, #0
/* while (set <= num_sets) { */
begin_flush_cache_impl_set_loop:
cmp w3, w0
b.lt done_flush_cache_impl_set_loop
/* const u64 cisw_value = (static_cast<u64>(way) << way_shift) | (static_cast<u64>(set) << set_shift) | level_sel_value; */
lsl x2, x5, x7
lsl x1, x0, x4
orr x1, x1, x2
orr x1, x1, x6
/* __asm__ __volatile__("dc cisw, %0" :: "r"(cisw_value) : "memory"); */
dc cisw, x1
/* set++; */
add x0, x0, #1
/* } */
b begin_flush_cache_impl_set_loop
done_flush_cache_impl_set_loop:
/* way++; */
add x5, x5, 1
/* } */
b begin_flush_cache_impl_way_loop
done_flush_cache_impl_way_loop:
ret