arm-trusted-firmware/lib/aarch64/misc_helpers.S

184 lines
4.6 KiB
ArmAsm

/*
* Copyright (c) 2013-2014, ARM Limited and Contributors. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* Neither the name of ARM nor the names of its contributors may be used
* to endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <arch.h>
#include <asm_macros.S>
#include <assert_macros.S>
.globl get_afflvl_shift
.globl mpidr_mask_lower_afflvls
.globl eret
.globl smc
.globl zeromem16
.globl memcpy16
.globl disable_mmu_el3
.globl disable_mmu_icache_el3
#if SUPPORT_VFP
.globl enable_vfp
#endif
func get_afflvl_shift
cmp x0, #3
cinc x0, x0, eq
mov x1, #MPIDR_AFFLVL_SHIFT
lsl x0, x0, x1
ret
endfunc get_afflvl_shift
func mpidr_mask_lower_afflvls
cmp x1, #3
cinc x1, x1, eq
mov x2, #MPIDR_AFFLVL_SHIFT
lsl x2, x1, x2
lsr x0, x0, x2
lsl x0, x0, x2
ret
endfunc mpidr_mask_lower_afflvls
func eret
eret
endfunc eret
func smc
smc #0
endfunc smc
/* -----------------------------------------------------------------------
* void zeromem16(void *mem, unsigned int length);
*
* Initialise a memory region to 0.
* The memory address must be 16-byte aligned.
* -----------------------------------------------------------------------
*/
func zeromem16
#if ASM_ASSERTION
tst x0, #0xf
ASM_ASSERT(eq)
#endif
add x2, x0, x1
/* zero 16 bytes at a time */
z_loop16:
sub x3, x2, x0
cmp x3, #16
b.lt z_loop1
stp xzr, xzr, [x0], #16
b z_loop16
/* zero byte per byte */
z_loop1:
cmp x0, x2
b.eq z_end
strb wzr, [x0], #1
b z_loop1
z_end:
ret
endfunc zeromem16
/* --------------------------------------------------------------------------
* void memcpy16(void *dest, const void *src, unsigned int length)
*
* Copy length bytes from memory area src to memory area dest.
* The memory areas should not overlap.
* Destination and source addresses must be 16-byte aligned.
* --------------------------------------------------------------------------
*/
func memcpy16
#if ASM_ASSERTION
orr x3, x0, x1
tst x3, #0xf
ASM_ASSERT(eq)
#endif
/* copy 16 bytes at a time */
m_loop16:
cmp x2, #16
b.lt m_loop1
ldp x3, x4, [x1], #16
stp x3, x4, [x0], #16
sub x2, x2, #16
b m_loop16
/* copy byte per byte */
m_loop1:
cbz x2, m_end
ldrb w3, [x1], #1
strb w3, [x0], #1
subs x2, x2, #1
b.ne m_loop1
m_end:
ret
endfunc memcpy16
/* ---------------------------------------------------------------------------
* Disable the MMU at EL3
* This is implemented in assembler to ensure that the data cache is cleaned
* and invalidated after the MMU is disabled without any intervening cacheable
* data accesses
* ---------------------------------------------------------------------------
*/
func disable_mmu_el3
mov x1, #(SCTLR_M_BIT | SCTLR_C_BIT)
do_disable_mmu:
mrs x0, sctlr_el3
bic x0, x0, x1
msr sctlr_el3, x0
isb // ensure MMU is off
mov x0, #DCCISW // DCache clean and invalidate
b dcsw_op_all
endfunc disable_mmu_el3
func disable_mmu_icache_el3
mov x1, #(SCTLR_M_BIT | SCTLR_C_BIT | SCTLR_I_BIT)
b do_disable_mmu
endfunc disable_mmu_icache_el3
/* ---------------------------------------------------------------------------
* Enable the use of VFP at EL3
* ---------------------------------------------------------------------------
*/
#if SUPPORT_VFP
func enable_vfp
mrs x0, cpacr_el1
orr x0, x0, #CPACR_VFP_BITS
msr cpacr_el1, x0
mrs x0, cptr_el3
mov x1, #AARCH64_CPTR_TFP
bic x0, x0, x1
msr cptr_el3, x0
isb
ret
endfunc enable_vfp
#endif