Existing SMC wrapper call_smc() allows only 4 parameters and returns only one value. This is enough for existing use in PSCI code, but TEE mediator will need a call that is fully compatible with ARM SMCCC. This patch adds this call for both arm32 and arm64.
There was similar patch by Edgar E. Iglesias ([1]), but looks like it is abandoned.
[1] https://lists.xenproject.org/archives/html/xen-devel/2017-02/msg00636.html
CC: "Edgar E. Iglesias" edgar.iglesias@xilinx.com
Signed-off-by: Volodymyr Babchuk volodymyr_babchuk@epam.com ---
changes from "RFC": - response now stored in structure instead of array - added comments for arm32 assembly code - added offset (instead of magic values) for arm32 asm code
xen/arch/arm/arm32/Makefile | 1 + xen/arch/arm/arm32/smc.S | 39 +++++++++++++++++++++++++++++++++++++++ xen/arch/arm/arm64/Makefile | 1 + xen/arch/arm/arm64/asm-offsets.c | 4 ++++ xen/arch/arm/arm64/smc.S | 30 ++++++++++++++++++++++++++++++ xen/include/asm-arm/processor.h | 11 +++++++++++ 6 files changed, 86 insertions(+) create mode 100644 xen/arch/arm/arm32/smc.S create mode 100644 xen/arch/arm/arm64/smc.S
diff --git a/xen/arch/arm/arm32/Makefile b/xen/arch/arm/arm32/Makefile index 0ac254f..c69f35e 100644 --- a/xen/arch/arm/arm32/Makefile +++ b/xen/arch/arm/arm32/Makefile @@ -10,4 +10,5 @@ obj-y += proc-v7.o proc-caxx.o obj-y += smpboot.o obj-y += traps.o obj-y += vfp.o +obj-y += smc.o
diff --git a/xen/arch/arm/arm32/smc.S b/xen/arch/arm/arm32/smc.S new file mode 100644 index 0000000..56f7982 --- /dev/null +++ b/xen/arch/arm/arm32/smc.S @@ -0,0 +1,39 @@ +/* + * xen/arch/arm/arm32/smc.S + * + * Wrapper for Secure Monitors Calls + * + * 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. + */ + +#include <asm/macros.h> + +/* + * void call_smccc_smc(register_t a0, register_t a1, register_t a2, + * register_t a3, register_t a4, register_t a5, + * register_t a6, register_t a7, struct smccc_res *res) + */ +ENTRY(call_smccc_smc) + mov r12, sp + push {r4-r7} + /* + * According to ARMv7 (or aarch32) ABI, first 4 parameters of + * call_smccc_smc are passed in r0-r3 and other 4 are on stack. + * Load a4-a7 from stack to r4-r7. + */ + ldm r12, {r4-r7} + smc #0 + pop {r4-r7} + /* Load pointer to res (4th parameter on stack) to r12 */ + ldr r12, [sp, #(4 * 4)] + /* Store returned results from r0-r3 to res */ + stm r12, {r0-r3} + bx lr diff --git a/xen/arch/arm/arm64/Makefile b/xen/arch/arm/arm64/Makefile index bb5c610..7ecdad7 100644 --- a/xen/arch/arm/arm64/Makefile +++ b/xen/arch/arm/arm64/Makefile @@ -9,6 +9,7 @@ obj-y += entry.o obj-y += insn.o obj-$(CONFIG_LIVEPATCH) += livepatch.o obj-y += smpboot.o +obj-y += smc.o obj-y += traps.o obj-y += vfp.o obj-y += vsysreg.o diff --git a/xen/arch/arm/arm64/asm-offsets.c b/xen/arch/arm/arm64/asm-offsets.c index ce24e44..5353fe8 100644 --- a/xen/arch/arm/arm64/asm-offsets.c +++ b/xen/arch/arm/arm64/asm-offsets.c @@ -50,6 +50,10 @@ void __dummy__(void)
BLANK(); OFFSET(INITINFO_stack, struct init_info, stack); + + BLANK(); + OFFSET(SMCCC_RES_a0, struct smccc_res, a0); + OFFSET(SMCCC_RES_a2, struct smccc_res, a2); }
/* diff --git a/xen/arch/arm/arm64/smc.S b/xen/arch/arm/arm64/smc.S new file mode 100644 index 0000000..40843c0 --- /dev/null +++ b/xen/arch/arm/arm64/smc.S @@ -0,0 +1,30 @@ +/* + * xen/arch/arm/arm64/smc.S + * + * Wrapper for Secure Monitors Calls + * + * 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. + */ + +#include <asm/asm_defns.h> +#include <asm/macros.h> + +/* + * void call_smccc_smc(register_t a0, register_t a1, register_t a2, + * register_t a3, register_t a4, register_t a5, + * register_t a6, register_t a7, struct smccc_res *res) + */ +ENTRY(call_smccc_smc) + smc #0 + ldr x4, [sp] + stp x0, x1, [x4, #SMCCC_RES_a0] + stp x2, x3, [x4, #SMCCC_RES_a2] + ret diff --git a/xen/include/asm-arm/processor.h b/xen/include/asm-arm/processor.h index 222a02d..946a2db 100644 --- a/xen/include/asm-arm/processor.h +++ b/xen/include/asm-arm/processor.h @@ -650,6 +650,13 @@ union hsr {
}; + +struct smccc_res { + register_t a0; + register_t a1; + register_t a2; + register_t a3; +}; #endif
/* HSR.EC == HSR_CP{15,14,10}_32 */ @@ -815,6 +822,10 @@ void vcpu_regs_user_to_hyp(struct vcpu *vcpu, int call_smc(register_t function_id, register_t arg0, register_t arg1, register_t arg2);
+void call_smccc_smc(register_t a0, register_t a1, register_t a2, + register_t a3, register_t a4, register_t a5, + register_t a6, register_t a7, struct smccc_res *res); + void do_trap_hyp_serror(struct cpu_user_regs *regs);
void do_trap_guest_serror(struct cpu_user_regs *regs);