This commit adds functions issuing calls to secure monitor or hypervisore. This allows using services such as Power State Coordination Interface (PSCI) provided by firmware, e.g. ARM Trusted Firmware (ATF)
The SMC call can destroy all registers declared temporary by the calling conventions. The clobber list is "x0..x17" because of this
Signed-off-by: Sergey Temerkhanov s.temerkhanov@gmail.com Signed-off-by: Corey Minyard cminyard@mvista.com Signed-off-by: Radha Mohan Chintakuntla rchintakuntla@cavium.com Reviewed-by: Simon Glass sjg@chromium.org
---
Changes in v6: None Changes in v5: None Changes in v4: - Document FW calls
Changes in v3: - Fixed clobber lists (thanks to Corey)
Changes in v2: None
arch/arm/cpu/armv8/Makefile | 1 + arch/arm/cpu/armv8/fwcall.c | 75 +++++++++++++++++++++++++++++++++++++++++++ arch/arm/include/asm/system.h | 21 ++++++++++++ 3 files changed, 97 insertions(+) create mode 100644 arch/arm/cpu/armv8/fwcall.c
diff --git a/arch/arm/cpu/armv8/Makefile b/arch/arm/cpu/armv8/Makefile index adb11b3..7579ea7 100644 --- a/arch/arm/cpu/armv8/Makefile +++ b/arch/arm/cpu/armv8/Makefile @@ -14,6 +14,7 @@ obj-y += exceptions.o obj-y += cache.o obj-y += tlb.o obj-y += transition.o +obj-y += fwcall.o
obj-$(CONFIG_FSL_LSCH3) += fsl-lsch3/ obj-$(CONFIG_ARCH_ZYNQMP) += zynqmp/ diff --git a/arch/arm/cpu/armv8/fwcall.c b/arch/arm/cpu/armv8/fwcall.c new file mode 100644 index 0000000..9efcc5a --- /dev/null +++ b/arch/arm/cpu/armv8/fwcall.c @@ -0,0 +1,75 @@ +/** + * (C) Copyright 2014, Cavium Inc. + * + * SPDX-License-Identifier: GPL-2.0+ +**/ + +#include <asm-offsets.h> +#include <config.h> +#include <version.h> +#include <asm/macro.h> +#include <asm/system.h> + +/* + * Issue the hypervisor call + * + * x0~x7: input arguments + * x0~x3: output arguments + */ +void hvc_call(struct pt_regs *args) +{ + asm volatile( + "ldr x0, %0\n" + "ldr x1, %1\n" + "ldr x2, %2\n" + "ldr x3, %3\n" + "ldr x4, %4\n" + "ldr x5, %5\n" + "ldr x6, %6\n" + "ldr x7, %7\n" + "hvc #0\n" + "str x0, %0\n" + "str x1, %1\n" + "str x2, %2\n" + "str x3, %3\n" + : "+m" (args->regs[0]), "+m" (args->regs[1]), + "+m" (args->regs[2]), "+m" (args->regs[3]) + : "m" (args->regs[4]), "m" (args->regs[5]), + "m" (args->regs[6]), "m" (args->regs[7]) + : "x0", "x1", "x2", "x3", "x4", "x5", "x6", "x7", + "x8", "x9", "x10", "x11", "x12", "x13", "x14", "x15", + "x16", "x17"); +} + +/* + * void smc_call(arg0, arg1...arg7) + * + * issue the secure monitor call + * + * x0~x7: input arguments + * x0~x3: output arguments + */ + +void smc_call(struct pt_regs *args) +{ + asm volatile( + "ldr x0, %0\n" + "ldr x1, %1\n" + "ldr x2, %2\n" + "ldr x3, %3\n" + "ldr x4, %4\n" + "ldr x5, %5\n" + "ldr x6, %6\n" + "smc #0\n" + "str x0, %0\n" + "str x1, %1\n" + "str x2, %2\n" + "str x3, %3\n" + : "+m" (args->regs[0]), "+m" (args->regs[1]), + "+m" (args->regs[2]), "+m" (args->regs[3]) + : "m" (args->regs[4]), "m" (args->regs[5]), + "m" (args->regs[6]) + : "x0", "x1", "x2", "x3", "x4", "x5", "x6", "x7", + "x8", "x9", "x10", "x11", "x12", "x13", "x14", "x15", + "x16", "x17"); +} diff --git a/arch/arm/include/asm/system.h b/arch/arm/include/asm/system.h index 9288541..f3e2d1b 100644 --- a/arch/arm/include/asm/system.h +++ b/arch/arm/include/asm/system.h @@ -1,6 +1,9 @@ #ifndef __ASM_ARM_SYSTEM_H #define __ASM_ARM_SYSTEM_H
+#include <common.h> +#include <linux/compiler.h> + #ifdef CONFIG_ARM64
/* @@ -104,6 +107,24 @@ void smp_kick_all_cpus(void);
void flush_l3_cache(void);
+/* + *Issue a hypervisor call in accordance with ARM "SMC Calling convention", + * DEN0028A + * + * @args: input and output arguments + * + */ +void hvc_call(struct pt_regs *args); + +/* + *Issue a secure monitor call in accordance with ARM "SMC Calling convention", + * DEN0028A + * + * @args: input and output arguments + * + */ +void smc_call(struct pt_regs *args); + #endif /* __ASSEMBLY__ */
#else /* CONFIG_ARM64 */