[PATCH v2 01/10] ARM: import opcode helpers from Linux kernel

Roland Hieber r.hieber at pengutronix.de
Mon Mar 26 03:06:40 PDT 2018


Hmm. I don't see any sdhci driver being loaded on RPi 2, resulting in no 
SD Card. But this is probably not related to the changes in this series.

Otherwise, as for v1:

Tested-on: bcm2835-rpi, bcm2836-rpi-2, bcm2837-rpi-3
Tested-by: Roland Hieber <r.hieber at pengutronix.de>

On 24.03.2018 00:14, Lucas Stach wrote:
> Those are needed to generate some of the ARM SEC and VIRT
> opcodes in a portable way.
> 
> Signed-off-by: Lucas Stach <l.stach at pengutronix.de>
> ---
>   arch/arm/include/asm/opcodes-virt.h |  39 ++++++
>   arch/arm/include/asm/opcodes.h      | 231 ++++++++++++++++++++++++++++++++++++
>   2 files changed, 270 insertions(+)
>   create mode 100644 arch/arm/include/asm/opcodes-virt.h
>   create mode 100644 arch/arm/include/asm/opcodes.h
> 
> diff --git a/arch/arm/include/asm/opcodes-virt.h b/arch/arm/include/asm/opcodes-virt.h
> new file mode 100644
> index 000000000000..efcfdf92d9d5
> --- /dev/null
> +++ b/arch/arm/include/asm/opcodes-virt.h
> @@ -0,0 +1,39 @@
> +/*
> + * opcodes-virt.h: Opcode definitions for the ARM virtualization extensions
> + * Copyright (C) 2012  Linaro Limited
> + *
> + * 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; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * 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 Street, Fifth Floor, Boston, MA 02110-1301 USA.
> + */
> +#ifndef __ASM_ARM_OPCODES_VIRT_H
> +#define __ASM_ARM_OPCODES_VIRT_H
> +
> +#include <asm/opcodes.h>
> +
> +#define __HVC(imm16) __inst_arm_thumb32(				\
> +	0xE1400070 | (((imm16) & 0xFFF0) << 4) | ((imm16) & 0x000F),	\
> +	0xF7E08000 | (((imm16) & 0xF000) << 4) | ((imm16) & 0x0FFF)	\
> +)
> +
> +#define __ERET	__inst_arm_thumb32(					\
> +	0xE160006E,							\
> +	0xF3DE8F00							\
> +)
> +
> +#define __MSR_ELR_HYP(regnum)	__inst_arm_thumb32(			\
> +	0xE12EF300 | regnum,						\
> +	0xF3808E30 | (regnum << 16)					\
> +)
> +
> +#endif /* ! __ASM_ARM_OPCODES_VIRT_H */
> diff --git a/arch/arm/include/asm/opcodes.h b/arch/arm/include/asm/opcodes.h
> new file mode 100644
> index 000000000000..a78bf5d2c518
> --- /dev/null
> +++ b/arch/arm/include/asm/opcodes.h
> @@ -0,0 +1,231 @@
> +/*
> + *  arch/arm/include/asm/opcodes.h
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#ifndef __ASM_ARM_OPCODES_H
> +#define __ASM_ARM_OPCODES_H
> +
> +#ifndef __ASSEMBLY__
> +#include <linux/linkage.h>
> +extern asmlinkage unsigned int arm_check_condition(u32 opcode, u32 psr);
> +#endif
> +
> +#define ARM_OPCODE_CONDTEST_FAIL   0
> +#define ARM_OPCODE_CONDTEST_PASS   1
> +#define ARM_OPCODE_CONDTEST_UNCOND 2
> +
> +
> +/*
> + * Assembler opcode byteswap helpers.
> + * These are only intended for use by this header: don't use them directly,
> + * because they will be suboptimal in most cases.
> + */
> +#define ___asm_opcode_swab32(x) (	\
> +	  (((x) << 24) & 0xFF000000)	\
> +	| (((x) <<  8) & 0x00FF0000)	\
> +	| (((x) >>  8) & 0x0000FF00)	\
> +	| (((x) >> 24) & 0x000000FF)	\
> +)
> +#define ___asm_opcode_swab16(x) (	\
> +	  (((x) << 8) & 0xFF00)		\
> +	| (((x) >> 8) & 0x00FF)		\
> +)
> +#define ___asm_opcode_swahb32(x) (	\
> +	  (((x) << 8) & 0xFF00FF00)	\
> +	| (((x) >> 8) & 0x00FF00FF)	\
> +)
> +#define ___asm_opcode_swahw32(x) (	\
> +	  (((x) << 16) & 0xFFFF0000)	\
> +	| (((x) >> 16) & 0x0000FFFF)	\
> +)
> +#define ___asm_opcode_identity32(x) ((x) & 0xFFFFFFFF)
> +#define ___asm_opcode_identity16(x) ((x) & 0xFFFF)
> +
> +
> +/*
> + * Opcode byteswap helpers
> + *
> + * These macros help with converting instructions between a canonical integer
> + * format and in-memory representation, in an endianness-agnostic manner.
> + *
> + * __mem_to_opcode_*() convert from in-memory representation to canonical form.
> + * __opcode_to_mem_*() convert from canonical form to in-memory representation.
> + *
> + *
> + * Canonical instruction representation:
> + *
> + *	ARM:		0xKKLLMMNN
> + *	Thumb 16-bit:	0x0000KKLL, where KK < 0xE8
> + *	Thumb 32-bit:	0xKKLLMMNN, where KK >= 0xE8
> + *
> + * There is no way to distinguish an ARM instruction in canonical representation
> + * from a Thumb instruction (just as these cannot be distinguished in memory).
> + * Where this distinction is important, it needs to be tracked separately.
> + *
> + * Note that values in the range 0x0000E800..0xE7FFFFFF intentionally do not
> + * represent any valid Thumb-2 instruction.  For this range,
> + * __opcode_is_thumb32() and __opcode_is_thumb16() will both be false.
> + *
> + * The ___asm variants are intended only for use by this header, in situations
> + * involving inline assembler.  For .S files, the normal __opcode_*() macros
> + * should do the right thing.
> + */
> +#ifdef __ASSEMBLY__
> +
> +#define ___opcode_swab32(x) ___asm_opcode_swab32(x)
> +#define ___opcode_swab16(x) ___asm_opcode_swab16(x)
> +#define ___opcode_swahb32(x) ___asm_opcode_swahb32(x)
> +#define ___opcode_swahw32(x) ___asm_opcode_swahw32(x)
> +#define ___opcode_identity32(x) ___asm_opcode_identity32(x)
> +#define ___opcode_identity16(x) ___asm_opcode_identity16(x)
> +
> +#else /* ! __ASSEMBLY__ */
> +
> +#include <linux/types.h>
> +#include <linux/swab.h>
> +
> +#define ___opcode_swab32(x) swab32(x)
> +#define ___opcode_swab16(x) swab16(x)
> +#define ___opcode_swahb32(x) swahb32(x)
> +#define ___opcode_swahw32(x) swahw32(x)
> +#define ___opcode_identity32(x) ((u32)(x))
> +#define ___opcode_identity16(x) ((u16)(x))
> +
> +#endif /* ! __ASSEMBLY__ */
> +
> +
> +#ifdef CONFIG_CPU_ENDIAN_BE8
> +
> +#define __opcode_to_mem_arm(x) ___opcode_swab32(x)
> +#define __opcode_to_mem_thumb16(x) ___opcode_swab16(x)
> +#define __opcode_to_mem_thumb32(x) ___opcode_swahb32(x)
> +#define ___asm_opcode_to_mem_arm(x) ___asm_opcode_swab32(x)
> +#define ___asm_opcode_to_mem_thumb16(x) ___asm_opcode_swab16(x)
> +#define ___asm_opcode_to_mem_thumb32(x) ___asm_opcode_swahb32(x)
> +
> +#else /* ! CONFIG_CPU_ENDIAN_BE8 */
> +
> +#define __opcode_to_mem_arm(x) ___opcode_identity32(x)
> +#define __opcode_to_mem_thumb16(x) ___opcode_identity16(x)
> +#define ___asm_opcode_to_mem_arm(x) ___asm_opcode_identity32(x)
> +#define ___asm_opcode_to_mem_thumb16(x) ___asm_opcode_identity16(x)
> +#ifndef CONFIG_CPU_ENDIAN_BE32
> +/*
> + * On BE32 systems, using 32-bit accesses to store Thumb instructions will not
> + * work in all cases, due to alignment constraints.  For now, a correct
> + * version is not provided for BE32.
> + */
> +#define __opcode_to_mem_thumb32(x) ___opcode_swahw32(x)
> +#define ___asm_opcode_to_mem_thumb32(x) ___asm_opcode_swahw32(x)
> +#endif
> +
> +#endif /* ! CONFIG_CPU_ENDIAN_BE8 */
> +
> +#define __mem_to_opcode_arm(x) __opcode_to_mem_arm(x)
> +#define __mem_to_opcode_thumb16(x) __opcode_to_mem_thumb16(x)
> +#ifndef CONFIG_CPU_ENDIAN_BE32
> +#define __mem_to_opcode_thumb32(x) __opcode_to_mem_thumb32(x)
> +#endif
> +
> +/* Operations specific to Thumb opcodes */
> +
> +/* Instruction size checks: */
> +#define __opcode_is_thumb32(x) (		\
> +	   ((x) & 0xF8000000) == 0xE8000000	\
> +	|| ((x) & 0xF0000000) == 0xF0000000	\
> +)
> +#define __opcode_is_thumb16(x) (					\
> +	   ((x) & 0xFFFF0000) == 0					\
> +	&& !(((x) & 0xF800) == 0xE800 || ((x) & 0xF000) == 0xF000)	\
> +)
> +
> +/* Operations to construct or split 32-bit Thumb instructions: */
> +#define __opcode_thumb32_first(x) (___opcode_identity16((x) >> 16))
> +#define __opcode_thumb32_second(x) (___opcode_identity16(x))
> +#define __opcode_thumb32_compose(first, second) (			\
> +	  (___opcode_identity32(___opcode_identity16(first)) << 16)	\
> +	| ___opcode_identity32(___opcode_identity16(second))		\
> +)
> +#define ___asm_opcode_thumb32_first(x) (___asm_opcode_identity16((x) >> 16))
> +#define ___asm_opcode_thumb32_second(x) (___asm_opcode_identity16(x))
> +#define ___asm_opcode_thumb32_compose(first, second) (			    \
> +	  (___asm_opcode_identity32(___asm_opcode_identity16(first)) << 16) \
> +	| ___asm_opcode_identity32(___asm_opcode_identity16(second))	    \
> +)
> +
> +/*
> + * Opcode injection helpers
> + *
> + * In rare cases it is necessary to assemble an opcode which the
> + * assembler does not support directly, or which would normally be
> + * rejected because of the CFLAGS or AFLAGS used to build the affected
> + * file.
> + *
> + * Before using these macros, consider carefully whether it is feasible
> + * instead to change the build flags for your file, or whether it really
> + * makes sense to support old assembler versions when building that
> + * particular kernel feature.
> + *
> + * The macros defined here should only be used where there is no viable
> + * alternative.
> + *
> + *
> + * __inst_arm(x): emit the specified ARM opcode
> + * __inst_thumb16(x): emit the specified 16-bit Thumb opcode
> + * __inst_thumb32(x): emit the specified 32-bit Thumb opcode
> + *
> + * __inst_arm_thumb16(arm, thumb): emit either the specified arm or
> + *	16-bit Thumb opcode, depending on whether an ARM or Thumb-2
> + *	kernel is being built
> + *
> + * __inst_arm_thumb32(arm, thumb): emit either the specified arm or
> + *	32-bit Thumb opcode, depending on whether an ARM or Thumb-2
> + *	kernel is being built
> + *
> + *
> + * Note that using these macros directly is poor practice.  Instead, you
> + * should use them to define human-readable wrapper macros to encode the
> + * instructions that you care about.  In code which might run on ARMv7 or
> + * above, you can usually use the __inst_arm_thumb{16,32} macros to
> + * specify the ARM and Thumb alternatives at the same time.  This ensures
> + * that the correct opcode gets emitted depending on the instruction set
> + * used for the kernel build.
> + *
> + * Look at opcodes-virt.h for an example of how to use these macros.
> + */
> +#include <linux/stringify.h>
> +
> +#define __inst_arm(x) ___inst_arm(___asm_opcode_to_mem_arm(x))
> +#define __inst_thumb32(x) ___inst_thumb32(				\
> +	___asm_opcode_to_mem_thumb16(___asm_opcode_thumb32_first(x)),	\
> +	___asm_opcode_to_mem_thumb16(___asm_opcode_thumb32_second(x))	\
> +)
> +#define __inst_thumb16(x) ___inst_thumb16(___asm_opcode_to_mem_thumb16(x))
> +
> +#ifdef CONFIG_THUMB2_BAREBOX
> +#define __inst_arm_thumb16(arm_opcode, thumb_opcode) \
> +	__inst_thumb16(thumb_opcode)
> +#define __inst_arm_thumb32(arm_opcode, thumb_opcode) \
> +	__inst_thumb32(thumb_opcode)
> +#else
> +#define __inst_arm_thumb16(arm_opcode, thumb_opcode) __inst_arm(arm_opcode)
> +#define __inst_arm_thumb32(arm_opcode, thumb_opcode) __inst_arm(arm_opcode)
> +#endif
> +
> +/* Helpers for the helpers.  Don't use these directly. */
> +#ifdef __ASSEMBLY__
> +#define ___inst_arm(x) .long x
> +#define ___inst_thumb16(x) .short x
> +#define ___inst_thumb32(first, second) .short first, second
> +#else
> +#define ___inst_arm(x) ".long " __stringify(x) "\n\t"
> +#define ___inst_thumb16(x) ".short " __stringify(x) "\n\t"
> +#define ___inst_thumb32(first, second) \
> +	".short " __stringify(first) ", " __stringify(second) "\n\t"
> +#endif
> +
> +#endif /* __ASM_ARM_OPCODES_H */
> 

-- 
Pengutronix e.K.                  | Roland Hieber               |
Industrial Linux Solutions        | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim | Phone: +49-5121-206917-5086 |
Amtsgericht Hildesheim, HRA 2686  | Fax:   +49-5121-206917-5555 |



More information about the barebox mailing list