mirror of
https://github.com/brain-hackers/u-boot-brain
synced 2024-06-09 23:36:03 +09:00
arm: armv7: allow unaligned memory access
The UEFI spec mandates that unaligned memory access should be enabled if supported by the CPU architecture. This patch implements the function unaligned_access() to reset the aligned access flag in the system control register (SCTLR). It is called when the bootefi command is invoked. Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de> [agraf: fix SPDX identifier] Signed-off-by: Alexander Graf <agraf@suse.de>
This commit is contained in:
parent
c3b11dea7c
commit
78f90aaeec
|
@ -12,6 +12,10 @@ obj-y += syslib.o
|
||||||
|
|
||||||
obj-$(CONFIG_SYS_ARM_MPU) += mpu_v7r.o
|
obj-$(CONFIG_SYS_ARM_MPU) += mpu_v7r.o
|
||||||
|
|
||||||
|
ifneq ($(CONFIG_SPL_BUILD),y)
|
||||||
|
obj-$(CONFIG_EFI_LOADER) += sctlr.o
|
||||||
|
endif
|
||||||
|
|
||||||
ifneq ($(CONFIG_SKIP_LOWLEVEL_INIT),y)
|
ifneq ($(CONFIG_SKIP_LOWLEVEL_INIT),y)
|
||||||
obj-y += lowlevel_init.o
|
obj-y += lowlevel_init.o
|
||||||
endif
|
endif
|
||||||
|
|
22
arch/arm/cpu/armv7/sctlr.S
Normal file
22
arch/arm/cpu/armv7/sctlr.S
Normal file
|
@ -0,0 +1,22 @@
|
||||||
|
/* SPDX-License-Identifier: GPL-2.0+ */
|
||||||
|
/*
|
||||||
|
* Routines to access the system control register
|
||||||
|
*
|
||||||
|
* Copyright (c) 2018 Heinrich Schuchardt
|
||||||
|
*/
|
||||||
|
|
||||||
|
#include <linux/linkage.h>
|
||||||
|
|
||||||
|
/*
|
||||||
|
* void allow_unaligned(void) - allow unaligned access
|
||||||
|
*
|
||||||
|
* This routine clears the aligned flag in the system control register.
|
||||||
|
* After calling this routine unaligned access does no longer lead to a
|
||||||
|
* data abort but is handled by the CPU.
|
||||||
|
*/
|
||||||
|
ENTRY(allow_unaligned)
|
||||||
|
mrc p15, 0, r0, c1, c0, 0 @ load system control register
|
||||||
|
bic r0, r0, #2 @ clear aligned flag
|
||||||
|
mcr p15, 0, r0, c1, c0, 0 @ write system control register
|
||||||
|
bx lr @ return
|
||||||
|
ENDPROC(allow_unaligned)
|
Loading…
Reference in New Issue
Block a user