mirror of
https://github.com/RGBCube/serenity
synced 2025-05-26 01:35:08 +00:00
137 lines
3 KiB
ArmAsm
137 lines
3 KiB
ArmAsm
/*
|
|
* Copyright (c) 2024, Sönke Holz <sholz830@gmail.com>
|
|
*
|
|
* SPDX-License-Identifier: BSD-2-Clause
|
|
*/
|
|
|
|
.section .text.asm_trap_handler
|
|
|
|
#define REGISTER_STATE_SIZE (36 * 8)
|
|
#if REGISTER_STATE_SIZE % 16 != 0
|
|
# error "REGISTER_STATE_SIZE is not a multiple of 16 bytes!"
|
|
#endif
|
|
|
|
#define SSTATUS_SLOT (31 * 8)
|
|
#define SEPC_SLOT (32 * 8)
|
|
#define SCAUSE_SLOT (33 * 8)
|
|
#define STVAL_SLOT (34 * 8)
|
|
#define USERSPACE_SP_SLOT (35 * 8)
|
|
|
|
.extern trap_handler
|
|
|
|
.p2align 2
|
|
.global asm_trap_handler
|
|
asm_trap_handler:
|
|
// FIXME: Handle traps from userspace
|
|
|
|
// Save the current register state to the current stack
|
|
// and enter the C++ trap handler
|
|
|
|
// Allocate stack space for trap frame
|
|
addi sp, sp, -REGISTER_STATE_SIZE
|
|
|
|
sd x1, 0*8(sp)
|
|
sd x2, 1*8(sp)
|
|
sd x3, 2*8(sp)
|
|
sd x4, 3*8(sp)
|
|
sd x5, 4*8(sp)
|
|
sd x6, 5*8(sp)
|
|
sd x7, 6*8(sp)
|
|
sd x8, 7*8(sp)
|
|
sd x9, 8*8(sp)
|
|
sd x10, 9*8(sp)
|
|
sd x11, 10*8(sp)
|
|
sd x12, 11*8(sp)
|
|
sd x13, 12*8(sp)
|
|
sd x14, 13*8(sp)
|
|
sd x15, 14*8(sp)
|
|
sd x16, 15*8(sp)
|
|
sd x17, 16*8(sp)
|
|
sd x18, 17*8(sp)
|
|
sd x19, 18*8(sp)
|
|
sd x20, 19*8(sp)
|
|
sd x21, 20*8(sp)
|
|
sd x22, 21*8(sp)
|
|
sd x23, 22*8(sp)
|
|
sd x24, 23*8(sp)
|
|
sd x25, 24*8(sp)
|
|
sd x26, 25*8(sp)
|
|
sd x27, 26*8(sp)
|
|
sd x28, 27*8(sp)
|
|
sd x29, 28*8(sp)
|
|
sd x30, 29*8(sp)
|
|
sd x31, 30*8(sp)
|
|
|
|
// Let's save some special registers
|
|
csrr t0, sstatus
|
|
sd t0, SSTATUS_SLOT(sp)
|
|
csrr t0, sepc
|
|
sd t0, SEPC_SLOT(sp)
|
|
|
|
// We also have to save those registers as interrupts are enabled during the page fault handling code.
|
|
// A page fault exception may be reported as an interrupt in the register dump, if we wouldn't do that.
|
|
csrr t0, scause
|
|
sd t0, SCAUSE_SLOT(sp)
|
|
csrr t0, stval
|
|
sd t0, STVAL_SLOT(sp)
|
|
|
|
// TODO
|
|
sd zero, USERSPACE_SP_SLOT(sp)
|
|
|
|
// Set up TrapFrame struct on the stack
|
|
mv t0, sp
|
|
addi sp, sp, -16
|
|
sd t0, 1*8(sp)
|
|
sd zero, 0*8(sp)
|
|
|
|
// Move stack pointer into first argument register
|
|
// and jump to the C++ trap handler
|
|
mv a0, sp
|
|
|
|
call trap_handler
|
|
|
|
// Remove TrapFrame from the stack
|
|
addi sp, sp, 16
|
|
|
|
// Restore special registers first
|
|
ld t0, SSTATUS_SLOT(sp)
|
|
csrw sstatus, t0
|
|
ld t0, SEPC_SLOT(sp)
|
|
csrw sepc, t0
|
|
|
|
ld x1, 0*8(sp)
|
|
// sp
|
|
ld x3, 2*8(sp)
|
|
ld x4, 3*8(sp)
|
|
ld x5, 4*8(sp)
|
|
ld x6, 5*8(sp)
|
|
ld x7, 6*8(sp)
|
|
ld x8, 7*8(sp)
|
|
ld x9, 8*8(sp)
|
|
ld x10, 9*8(sp)
|
|
ld x11, 10*8(sp)
|
|
ld x12, 11*8(sp)
|
|
ld x13, 12*8(sp)
|
|
ld x14, 13*8(sp)
|
|
ld x15, 14*8(sp)
|
|
ld x16, 15*8(sp)
|
|
ld x17, 16*8(sp)
|
|
ld x18, 17*8(sp)
|
|
ld x19, 18*8(sp)
|
|
ld x20, 19*8(sp)
|
|
ld x21, 20*8(sp)
|
|
ld x22, 21*8(sp)
|
|
ld x23, 22*8(sp)
|
|
ld x24, 23*8(sp)
|
|
ld x25, 24*8(sp)
|
|
ld x26, 25*8(sp)
|
|
ld x27, 26*8(sp)
|
|
ld x28, 27*8(sp)
|
|
ld x29, 28*8(sp)
|
|
ld x30, 29*8(sp)
|
|
ld x31, 30*8(sp)
|
|
|
|
ld x2, 1*8(sp)
|
|
|
|
addi sp, sp, REGISTER_STATE_SIZE
|
|
sret
|