From: Jens Wiklander jens.wiklander@linaro.org
Commit b329f95d70f3f955093e9a2b18ac1ed3587a8f73 upstream.
Adds implementation for arm-smccc and enables CONFIG_HAVE_SMCCC for architectures that may support arm-smccc. It's the responsibility of the caller to know if the SMC instruction is supported by the platform.
Reviewed-by: Lars Persson lars.persson@axis.com Signed-off-by: Jens Wiklander jens.wiklander@linaro.org Signed-off-by: Russell King rmk+kernel@arm.linux.org.uk Signed-off-by: Ard Biesheuvel ardb@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/arm/Kconfig | 1 arch/arm/kernel/Makefile | 2 + arch/arm/kernel/armksyms.c | 6 ++++ arch/arm/kernel/smccc-call.S | 62 +++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 71 insertions(+)
--- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -37,6 +37,7 @@ config ARM select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 select HAVE_ARCH_SECCOMP_FILTER if (AEABI && !OABI_COMPAT) select HAVE_ARCH_TRACEHOOK + select HAVE_ARM_SMCCC if CPU_V7 select HAVE_BPF_JIT select HAVE_CC_STACKPROTECTOR select HAVE_CONTEXT_TRACKING --- a/arch/arm/kernel/Makefile +++ b/arch/arm/kernel/Makefile @@ -91,4 +91,6 @@ obj-y += psci-call.o obj-$(CONFIG_SMP) += psci_smp.o endif
+obj-$(CONFIG_HAVE_ARM_SMCCC) += smccc-call.o + extra-y := $(head-y) vmlinux.lds --- a/arch/arm/kernel/armksyms.c +++ b/arch/arm/kernel/armksyms.c @@ -16,6 +16,7 @@ #include <linux/syscalls.h> #include <linux/uaccess.h> #include <linux/io.h> +#include <linux/arm-smccc.h>
#include <asm/checksum.h> #include <asm/ftrace.h> @@ -175,3 +176,8 @@ EXPORT_SYMBOL(__gnu_mcount_nc); EXPORT_SYMBOL(__pv_phys_pfn_offset); EXPORT_SYMBOL(__pv_offset); #endif + +#ifdef CONFIG_HAVE_ARM_SMCCC +EXPORT_SYMBOL(arm_smccc_smc); +EXPORT_SYMBOL(arm_smccc_hvc); +#endif --- /dev/null +++ b/arch/arm/kernel/smccc-call.S @@ -0,0 +1,62 @@ +/* + * Copyright (c) 2015, Linaro Limited + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * 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. + * + */ +#include <linux/linkage.h> + +#include <asm/opcodes-sec.h> +#include <asm/opcodes-virt.h> +#include <asm/unwind.h> + + /* + * Wrap c macros in asm macros to delay expansion until after the + * SMCCC asm macro is expanded. + */ + .macro SMCCC_SMC + __SMC(0) + .endm + + .macro SMCCC_HVC + __HVC(0) + .endm + + .macro SMCCC instr +UNWIND( .fnstart) + mov r12, sp + push {r4-r7} +UNWIND( .save {r4-r7}) + ldm r12, {r4-r7} + \instr + pop {r4-r7} + ldr r12, [sp, #(4 * 4)] + stm r12, {r0-r3} + bx lr +UNWIND( .fnend) + .endm + +/* + * void smccc_smc(unsigned long a0, unsigned long a1, unsigned long a2, + * unsigned long a3, unsigned long a4, unsigned long a5, + * unsigned long a6, unsigned long a7, struct arm_smccc_res *res) + */ +ENTRY(arm_smccc_smc) + SMCCC SMCCC_SMC +ENDPROC(arm_smccc_smc) + +/* + * void smccc_hvc(unsigned long a0, unsigned long a1, unsigned long a2, + * unsigned long a3, unsigned long a4, unsigned long a5, + * unsigned long a6, unsigned long a7, struct arm_smccc_res *res) + */ +ENTRY(arm_smccc_hvc) + SMCCC SMCCC_HVC +ENDPROC(arm_smccc_hvc)