coreboot-kgpe-d16/payloads/libpayload/arch/mips/exception_asm.S
Ionela Voinescu ce22c02387 libpayload: arch/mips: Add basic MIPS architecture support
Add the basic build infrastructure and architectural support
required to build for targets using the MIPS architecture.
This will require the addition of cache maintenance.

BUG=chrome-os-partner:31438
TEST=tested on Pistachio FPGA with Depthcharge as payload;
     successfully executed payload.
BRANCH=none

Change-Id: I75cfd0536860b6d84b53a567940fe6668d9b2cbb
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: 758c8cb9a6846e6ca32be409ec5f7a888ac9c888
Original-Signed-off-by: Ionela Voinescu <ionela.voinescu@imgtec.com>
Original-Change-Id: I0b9af983bf5032335a519ce2510a0b3aca082edf
Original-Reviewed-on: https://chromium-review.googlesource.com/219740
Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/8741
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
2015-03-21 11:07:50 +01:00

208 lines
4.1 KiB
ArmAsm

/*
* This file is part of the libpayload project.
*
* Copyright (C) 2014 Imagination Technologies
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* 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, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#define STATUS_REGISTER $12,0
#define BOOT_EXC_VECTOR_MASK (1 << 22)
#define EBASE_REGISTER $15,1
#define WRITE_GATE_MASK (1 << 11)
#define EXCEPTION_BASE_MASK (0xFFFFF000)
/* Don't reorder instructions */
.set noreorder
.set noat
.align 4
.global exception_stack_end
exception_stack_end:
.word 0
.global exception_state_ptr
exception_state_ptr:
.word 0
/* Temporary variables. */
ret_addr:
.word 0
exception_sp:
.word 0
vector:
.word 0
/* Cache error */
.org 0x100
li $v0, 0x0
la $at, vector
sw $v0, 0x00($at)
b exception_common
nop
/* TLB refill and all others */
.org 0x180
li $v0, 0x1
la $at, vector
sw $v0, 0x00($at)
b exception_common
nop
/* Interrupt */
.org 0x200
li $v0, 0x2
la $at, vector
sw $v0, 0x00($at)
b exception_common
nop
/* EJTAG debug exception */
.org 0x480
li $v0, 0x3
la $at, vector
sw $v0, 0x00($at)
b exception_common
nop
exception_common:
/* Obtain return address of exception */
la $v0, ret_addr
sw $ra, 0x00($v0)
/* Initialize $gp */
bal 1f
nop
.word _gp
1:
lw $gp, 0($ra)
la $at, exception_sp
sw $sp, 0x00($at)
lw $sp, exception_state_ptr
/* Save all registers */
sw $zero, 0x00($sp)
sw $at, 0x04($sp)
sw $v0, 0x08($sp)
sw $v1, 0x0C($sp)
sw $a0, 0x10($sp)
sw $a1, 0x14($sp)
sw $a2, 0x18($sp)
sw $a3, 0x1C($sp)
sw $t0, 0x20($sp)
sw $t1, 0x34($sp)
sw $t2, 0x28($sp)
sw $t3, 0x2C($sp)
sw $t4, 0x30($sp)
sw $t5, 0x34($sp)
sw $t6, 0x38($sp)
sw $t7, 0x3C($sp)
sw $s0, 0x40($sp)
sw $s1, 0x44($sp)
sw $s2, 0x48($sp)
sw $s3, 0x4C($sp)
sw $s4, 0x50($sp)
sw $s5, 0x54($sp)
sw $s6, 0x58($sp)
sw $s7, 0x5C($sp)
sw $t8, 0x60($sp)
sw $t9, 0x64($sp)
sw $k0, 0x68($sp)
sw $k1, 0x6C($sp)
sw $gp, 0x70($sp)
lw $v0, exception_sp
sw $v0, 0x74($sp)
sw $fp, 0x78($sp)
lw $v0, ret_addr
sw $v0, 0x7C($sp)
lw $v0, vector
sw $v0, 0x80($sp)
/* Point SP to the stack for C code */
lw $sp, exception_stack_end
/* Give control to exception dispatch */
la $a2, exception_dispatch
jalr $a2
nop
lw $sp, exception_state_ptr
/* Restore registers */
lw $zero, 0x00($sp)
lw $at, 0x04($sp)
lw $v0, 0x08($sp)
lw $v1, 0x0C($sp)
lw $a0, 0x10($sp)
lw $a1, 0x14($sp)
lw $a2, 0x18($sp)
lw $a3, 0x1C($sp)
lw $t0, 0x20($sp)
lw $t1, 0x24($sp)
lw $t2, 0x28($sp)
lw $t3, 0x2C($sp)
lw $t4, 0x30($sp)
lw $t5, 0x34($sp)
lw $t6, 0x38($sp)
lw $t7, 0x3C($sp)
lw $s0, 0x40($sp)
lw $s1, 0x44($sp)
lw $s2, 0x48($sp)
lw $s3, 0x4C($sp)
lw $s4, 0x50($sp)
lw $s5, 0x54($sp)
lw $s6, 0x58($sp)
lw $s7, 0x5C($sp)
lw $t8, 0x60($sp)
lw $t9, 0x64($sp)
lw $k0, 0x68($sp)
sw $k1, 0x6C($sp)
sw $gp, 0x70($sp)
sw $fp, 0x78($sp)
sw $ra, 0x7C($sp)
/* Return */
eret
.global exception_init_asm
exception_init_asm:
.set push
/* Make sure boot exception vector is 1 before writing EBASE */
mfc0 $t0, STATUS_REGISTER
li $t1, BOOT_EXC_VECTOR_MASK
or $t0, $t0, $t1
mtc0 $t0, STATUS_REGISTER
/*Prepare base address */
la $t1, exception_stack_end
li $t2, EXCEPTION_BASE_MASK
and $t1, $t1, $t2
/* Prepare EBASE register value */
mfc0 $t0, EBASE_REGISTER
li $t2, ~(EXCEPTION_BASE_MASK)
and $t0, $t0, $t2
/* Filling base address */
or $t0, $t0, $t1
/* Setting WG bit */
li $t2, WRITE_GATE_MASK
or $t0, $t0, $t2
mtc0 $t0, EBASE_REGISTER
/* Clear boot exception vector bit for EBASE value to take effect */
mfc0 $t0, STATUS_REGISTER
li $t1, ~BOOT_EXC_VECTOR_MASK
and $t0, $t0, $t1
mtc0 $t0, STATUS_REGISTER
.set pop
/* Return */
jr $ra