[PATCH v2 1/2] ARM: armv7: Add C wrapper for allow_unaligned()
Rename current assembler implementation of allow_unaligned() to v7_arch_cp15_allow_unaligned() and add it into armv7.h header, then add C wrapper of allow_unaligned().
This fixes misbehavior when linking U-Boot on ARMv7a i.MX6Q, where the CPU specific allow_unaligned() implementation was ignored and instead the __weak allow_unaligned() implementation from lib/efi_loader/efi_setup.c was used, which led to "data abort" just before booting Linux via tftp, in efi_dp_from_file() -> path_to_uefi() -> utf16_put() .
The problem is triggerd by c7c0ca37673 ("efi_loader: fix efi_dp_from_file()") . Adding the wrapper fixes the problem.
Fixes: 78f90aaeecc ("arm: armv7: allow unaligned memory access") Signed-off-by: Marek Vasut marex@denx.de --- V2: Update Fixes tag and commit message --- Cc: Fabio Estevam festevam@denx.de Cc: Heinrich Schuchardt xypron.glpk@gmx.de Cc: Ilias Apalodimas ilias.apalodimas@linaro.org Cc: Simon Glass sjg@chromium.org Cc: Tom Rini trini@konsulko.com --- arch/arm/cpu/armv7/cpu.c | 5 +++++ arch/arm/cpu/armv7/sctlr.S | 6 +++--- arch/arm/include/asm/armv7.h | 1 + 3 files changed, 9 insertions(+), 3 deletions(-)
diff --git a/arch/arm/cpu/armv7/cpu.c b/arch/arm/cpu/armv7/cpu.c index 68807d20997..6259ffa5108 100644 --- a/arch/arm/cpu/armv7/cpu.c +++ b/arch/arm/cpu/armv7/cpu.c @@ -83,3 +83,8 @@ int cleanup_before_linux(void) { return cleanup_before_linux_select(CBL_ALL); } + +void allow_unaligned(void) +{ + v7_arch_cp15_allow_unaligned(); +} diff --git a/arch/arm/cpu/armv7/sctlr.S b/arch/arm/cpu/armv7/sctlr.S index bd56e41afe1..d44b21498f6 100644 --- a/arch/arm/cpu/armv7/sctlr.S +++ b/arch/arm/cpu/armv7/sctlr.S @@ -8,15 +8,15 @@ #include <linux/linkage.h>
/* - * void allow_unaligned(void) - allow unaligned access + * void v7_arch_cp15_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) +ENTRY(v7_arch_cp15_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) +ENDPROC(v7_arch_cp15_allow_unaligned) diff --git a/arch/arm/include/asm/armv7.h b/arch/arm/include/asm/armv7.h index 2fb824b69e2..c002998ac0b 100644 --- a/arch/arm/include/asm/armv7.h +++ b/arch/arm/include/asm/armv7.h @@ -156,6 +156,7 @@ void v7_arch_cp15_set_l2aux_ctrl(u32 l2auxctrl, u32 cpu_midr, u32 cpu_rev); void v7_arch_cp15_set_acr(u32 acr, u32 cpu_midr, u32 cpu_rev_comb, u32 cpu_variant, u32 cpu_rev); +void v7_arch_cp15_allow_unaligned(void); #endif /* ! __ASSEMBLY__ */
#endif
Rename current assembler implementation of allow_unaligned() to arm11_arch_cp15_allow_unaligned() and add it into arm11.h header, then add C wrapper of allow_unaligned().
This fixes misbehavior when linking U-Boot, where the CPU specific allow_unaligned() implementation was ignored and instead the __weak allow_unaligned() implementation from lib/efi_loader/efi_setup.c was used, which led to "data abort" just before booting Linux via tftp, in efi_dp_from_file() -> path_to_uefi() -> utf16_put() .
The problem is triggerd by c7c0ca37673 ("efi_loader: fix efi_dp_from_file()") . Adding the wrapper fixes the problem.
Fixes: d47a774680d ("arm: arm11: allow unaligned memory access") Signed-off-by: Marek Vasut marex@denx.de --- V2: Update Fixes tag and commit message --- Cc: Fabio Estevam festevam@denx.de Cc: Heinrich Schuchardt xypron.glpk@gmx.de Cc: Ilias Apalodimas ilias.apalodimas@linaro.org Cc: Simon Glass sjg@chromium.org Cc: Tom Rini trini@konsulko.com --- arch/arm/cpu/arm11/cpu.c | 6 ++++++ arch/arm/cpu/arm11/sctlr.S | 6 +++--- arch/arm/include/asm/arm11.h | 12 ++++++++++++ 3 files changed, 21 insertions(+), 3 deletions(-) create mode 100644 arch/arm/include/asm/arm11.h
diff --git a/arch/arm/cpu/arm11/cpu.c b/arch/arm/cpu/arm11/cpu.c index ffe35111d58..1e16b89d006 100644 --- a/arch/arm/cpu/arm11/cpu.c +++ b/arch/arm/cpu/arm11/cpu.c @@ -20,6 +20,7 @@ #include <irq_func.h> #include <asm/cache.h> #include <asm/system.h> +#include <asm/arm11.h>
static void cache_flush(void);
@@ -43,6 +44,11 @@ int cleanup_before_linux (void) return 0; }
+void allow_unaligned(void) +{ + arm11_arch_cp15_allow_unaligned(); +} + static void cache_flush(void) { unsigned long i = 0; diff --git a/arch/arm/cpu/arm11/sctlr.S b/arch/arm/cpu/arm11/sctlr.S index 74a7fc4a25b..8722f8380c8 100644 --- a/arch/arm/cpu/arm11/sctlr.S +++ b/arch/arm/cpu/arm11/sctlr.S @@ -8,7 +8,7 @@ #include <linux/linkage.h>
/* - * void allow_unaligned(void) - allow unaligned access + * void arm11_arch_cp15_allow_unaligned(void) - allow unaligned access * * This routine sets the enable unaligned data support flag and clears the * aligned flag in the system control register. @@ -16,10 +16,10 @@ * data abort or undefined behavior but is handled by the CPU. * For details see the "ARM Architecture Reference Manual" for ARMv6. */ -ENTRY(allow_unaligned) +ENTRY(arm11_arch_cp15_allow_unaligned) mrc p15, 0, r0, c1, c0, 0 @ load system control register orr r0, r0, #1 << 22 @ set unaligned data support flag bic r0, r0, #2 @ clear aligned flag mcr p15, 0, r0, c1, c0, 0 @ write system control register bx lr @ return -ENDPROC(allow_unaligned) +ENDPROC(arm11_arch_cp15_allow_unaligned) diff --git a/arch/arm/include/asm/arm11.h b/arch/arm/include/asm/arm11.h new file mode 100644 index 00000000000..5276f735ef9 --- /dev/null +++ b/arch/arm/include/asm/arm11.h @@ -0,0 +1,12 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * Copyright (C) 2023 Marek Vasut marex@denx.de + */ +#ifndef ARM11_H +#define ARM11_H + +#ifndef __ASSEMBLY__ +void arm11_arch_cp15_allow_unaligned(void); +#endif /* ! __ASSEMBLY__ */ + +#endif /* ARM11_H */
participants (1)
-
Marek Vasut