blob: e211575a6ab2c3eb92da68ecc3ef9fc1f57d8fe6 [file] [log] [blame]
/*
* Copyright (c) 2022, ARM Limited. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#ifndef TRAP_HANDLE_H
#define TRAP_HANDLE_H
#include <stdbool.h>
#include <context.h>
#define ISS_SYSREG_OPCODE_MASK 0x3ffc1eUL
#define ISS_SYSREG_REG_MASK 0x0003e0UL
#define ISS_SYSREG_REG_SHIFT 5U
#define ISS_SYSREG_DIRECTION_MASK 0x000001UL
#define ISS_SYSREG_OPCODE_RNDR 0x30c808U
#define ISS_SYSREG_OPCODE_RNDRRS 0x32c808U
#define TRAP_RET_UNHANDLED -1
#define TRAP_RET_REPEAT 0
#define TRAP_RET_CONTINUE 1
#ifndef __ASSEMBLER__
static inline unsigned int get_sysreg_iss_rt(uint64_t esr)
{
return (esr & ISS_SYSREG_REG_MASK) >> ISS_SYSREG_REG_SHIFT;
}
static inline bool is_sysreg_iss_write(uint64_t esr)
{
return !(esr & ISS_SYSREG_DIRECTION_MASK);
}
/**
* handle_sysreg_trap() - Handle AArch64 system register traps from lower ELs
* @esr_el3: The content of ESR_EL3, containing the trap syndrome information
* @ctx: Pointer to the lower EL context, containing saved registers
*
* Called by the exception handler when a synchronous trap identifies as a
* system register trap (EC=0x18). ESR contains the encoding of the op[x] and
* CRm/CRn fields, to identify the system register, and the target/source
* GPR plus the direction (MRS/MSR). The lower EL's context can be altered
* by the function, to inject back the result of the emulation.
*
* Return: indication how to proceed with the trap:
* TRAP_RET_UNHANDLED(-1): trap is unhandled, trigger panic
* TRAP_RET_REPEAT(0): trap was handled, return to the trapping instruction
* (repeating it)
* TRAP_RET_CONTINUE(1): trap was handled, return to the next instruction
* (continuing after it)
*/
int handle_sysreg_trap(uint64_t esr_el3, cpu_context_t *ctx);
/* Prototypes for system register emulation handlers provided by platforms. */
int plat_handle_rng_trap(uint64_t esr_el3, cpu_context_t *ctx);
#endif /* __ASSEMBLER__ */
#endif