diff options
Diffstat (limited to 'arch/arm64/kernel/smccc-call.S')
| -rw-r--r-- | arch/arm64/kernel/smccc-call.S | 131 |
1 files changed, 131 insertions, 0 deletions
diff --git a/arch/arm64/kernel/smccc-call.S b/arch/arm64/kernel/smccc-call.S new file mode 100644 index 000000000..487381164 --- /dev/null +++ b/arch/arm64/kernel/smccc-call.S @@ -0,0 +1,131 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (c) 2015, Linaro Limited + */ +#include <linux/linkage.h> +#include <linux/arm-smccc.h> + +#include <asm/asm-offsets.h> +#include <asm/assembler.h> +#include <asm/thread_info.h> + +/* + * If we have SMCCC v1.3 and (as is likely) no SVE state in + * the registers then set the SMCCC hint bit to say there's no + * need to preserve it. Do this by directly adjusting the SMCCC + * function value which is already stored in x0 ready to be called. + */ +SYM_FUNC_START(__arm_smccc_sve_check) + + ldr_l x16, smccc_has_sve_hint + cbz x16, 2f + + get_current_task x16 + ldr x16, [x16, #TSK_TI_FLAGS] + tbnz x16, #TIF_FOREIGN_FPSTATE, 1f // Any live FP state? + tbnz x16, #TIF_SVE, 2f // Does that state include SVE? + +1: orr x0, x0, ARM_SMCCC_1_3_SVE_HINT + +2: ret +SYM_FUNC_END(__arm_smccc_sve_check) +EXPORT_SYMBOL(__arm_smccc_sve_check) + + .macro SMCCC instr + stp x29, x30, [sp, #-16]! + mov x29, sp +alternative_if ARM64_SVE + bl __arm_smccc_sve_check +alternative_else_nop_endif + \instr #0 + ldr x4, [sp, #16] + stp x0, x1, [x4, #ARM_SMCCC_RES_X0_OFFS] + stp x2, x3, [x4, #ARM_SMCCC_RES_X2_OFFS] + ldr x4, [sp, #24] + cbz x4, 1f /* no quirk structure */ + ldr x9, [x4, #ARM_SMCCC_QUIRK_ID_OFFS] + cmp x9, #ARM_SMCCC_QUIRK_QCOM_A6 + b.ne 1f + str x6, [x4, ARM_SMCCC_QUIRK_STATE_OFFS] +1: ldp x29, x30, [sp], #16 + ret + .endm + +/* + * void arm_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, + * struct arm_smccc_quirk *quirk) + */ +SYM_FUNC_START(__arm_smccc_smc) + SMCCC smc +SYM_FUNC_END(__arm_smccc_smc) +EXPORT_SYMBOL(__arm_smccc_smc) + +/* + * void arm_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, + * struct arm_smccc_quirk *quirk) + */ +SYM_FUNC_START(__arm_smccc_hvc) + SMCCC hvc +SYM_FUNC_END(__arm_smccc_hvc) +EXPORT_SYMBOL(__arm_smccc_hvc) + + .macro SMCCC_1_2 instr + /* Save `res` and free a GPR that won't be clobbered */ + stp x1, x19, [sp, #-16]! + + /* Ensure `args` won't be clobbered while loading regs in next step */ + mov x19, x0 + + /* Load the registers x0 - x17 from the struct arm_smccc_1_2_regs */ + ldp x0, x1, [x19, #ARM_SMCCC_1_2_REGS_X0_OFFS] + ldp x2, x3, [x19, #ARM_SMCCC_1_2_REGS_X2_OFFS] + ldp x4, x5, [x19, #ARM_SMCCC_1_2_REGS_X4_OFFS] + ldp x6, x7, [x19, #ARM_SMCCC_1_2_REGS_X6_OFFS] + ldp x8, x9, [x19, #ARM_SMCCC_1_2_REGS_X8_OFFS] + ldp x10, x11, [x19, #ARM_SMCCC_1_2_REGS_X10_OFFS] + ldp x12, x13, [x19, #ARM_SMCCC_1_2_REGS_X12_OFFS] + ldp x14, x15, [x19, #ARM_SMCCC_1_2_REGS_X14_OFFS] + ldp x16, x17, [x19, #ARM_SMCCC_1_2_REGS_X16_OFFS] + + \instr #0 + + /* Load the `res` from the stack */ + ldr x19, [sp] + + /* Store the registers x0 - x17 into the result structure */ + stp x0, x1, [x19, #ARM_SMCCC_1_2_REGS_X0_OFFS] + stp x2, x3, [x19, #ARM_SMCCC_1_2_REGS_X2_OFFS] + stp x4, x5, [x19, #ARM_SMCCC_1_2_REGS_X4_OFFS] + stp x6, x7, [x19, #ARM_SMCCC_1_2_REGS_X6_OFFS] + stp x8, x9, [x19, #ARM_SMCCC_1_2_REGS_X8_OFFS] + stp x10, x11, [x19, #ARM_SMCCC_1_2_REGS_X10_OFFS] + stp x12, x13, [x19, #ARM_SMCCC_1_2_REGS_X12_OFFS] + stp x14, x15, [x19, #ARM_SMCCC_1_2_REGS_X14_OFFS] + stp x16, x17, [x19, #ARM_SMCCC_1_2_REGS_X16_OFFS] + + /* Restore original x19 */ + ldp xzr, x19, [sp], #16 + ret +.endm + +/* + * void arm_smccc_1_2_hvc(const struct arm_smccc_1_2_regs *args, + * struct arm_smccc_1_2_regs *res); + */ +SYM_FUNC_START(arm_smccc_1_2_hvc) + SMCCC_1_2 hvc +SYM_FUNC_END(arm_smccc_1_2_hvc) +EXPORT_SYMBOL(arm_smccc_1_2_hvc) + +/* + * void arm_smccc_1_2_smc(const struct arm_smccc_1_2_regs *args, + * struct arm_smccc_1_2_regs *res); + */ +SYM_FUNC_START(arm_smccc_1_2_smc) + SMCCC_1_2 smc +SYM_FUNC_END(arm_smccc_1_2_smc) +EXPORT_SYMBOL(arm_smccc_1_2_smc) |