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Diffstat (limited to 'include/arch/aarch32/smccc_helpers.h')
| -rw-r--r-- | include/arch/aarch32/smccc_helpers.h | 177 |
1 files changed, 177 insertions, 0 deletions
diff --git a/include/arch/aarch32/smccc_helpers.h b/include/arch/aarch32/smccc_helpers.h new file mode 100644 index 0000000..2ce7874 --- /dev/null +++ b/include/arch/aarch32/smccc_helpers.h @@ -0,0 +1,177 @@ +/* + * Copyright (c) 2016-2019, ARM Limited and Contributors. All rights reserved. + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +#ifndef SMCCC_HELPERS_H +#define SMCCC_HELPERS_H + +#include <lib/smccc.h> + +/* These are offsets to registers in smc_ctx_t */ +#define SMC_CTX_GPREG_R0 U(0x0) +#define SMC_CTX_GPREG_R1 U(0x4) +#define SMC_CTX_GPREG_R2 U(0x8) +#define SMC_CTX_GPREG_R3 U(0xC) +#define SMC_CTX_GPREG_R4 U(0x10) +#define SMC_CTX_GPREG_R5 U(0x14) +#define SMC_CTX_SP_USR U(0x34) +#define SMC_CTX_SPSR_MON U(0x78) +#define SMC_CTX_SP_MON U(0x7C) +#define SMC_CTX_LR_MON U(0x80) +#define SMC_CTX_SCR U(0x84) +#define SMC_CTX_PMCR U(0x88) +#define SMC_CTX_SIZE U(0x90) + +#ifndef __ASSEMBLER__ + +#include <stdint.h> + +#include <lib/cassert.h> + +/* + * The generic structure to save arguments and callee saved registers during + * an SMC. Also this structure is used to store the result return values after + * the completion of SMC service. + */ +typedef struct smc_ctx { + u_register_t r0; + u_register_t r1; + u_register_t r2; + u_register_t r3; + u_register_t r4; + u_register_t r5; + u_register_t r6; + u_register_t r7; + u_register_t r8; + u_register_t r9; + u_register_t r10; + u_register_t r11; + u_register_t r12; + /* spsr_usr doesn't exist */ + u_register_t sp_usr; + u_register_t lr_usr; + u_register_t spsr_irq; + u_register_t sp_irq; + u_register_t lr_irq; + u_register_t spsr_fiq; + u_register_t sp_fiq; + u_register_t lr_fiq; + u_register_t spsr_svc; + u_register_t sp_svc; + u_register_t lr_svc; + u_register_t spsr_abt; + u_register_t sp_abt; + u_register_t lr_abt; + u_register_t spsr_und; + u_register_t sp_und; + u_register_t lr_und; + u_register_t spsr_mon; + /* + * `sp_mon` will point to the C runtime stack in monitor mode. But prior + * to exit from SMC, this will point to the `smc_ctx_t` so that + * on next entry due to SMC, the `smc_ctx_t` can be easily accessed. + */ + u_register_t sp_mon; + u_register_t lr_mon; + u_register_t scr; + u_register_t pmcr; + /* + * The workaround for CVE-2017-5715 requires storing information in + * the bottom 3 bits of the stack pointer. Add a padding field to + * force the size of the struct to be a multiple of 8. + */ + u_register_t pad; +} smc_ctx_t __aligned(8); + +/* + * Compile time assertions related to the 'smc_context' structure to + * ensure that the assembler and the compiler view of the offsets of + * the structure members is the same. + */ +CASSERT(SMC_CTX_GPREG_R0 == __builtin_offsetof(smc_ctx_t, r0), \ + assert_smc_ctx_greg_r0_offset_mismatch); +CASSERT(SMC_CTX_GPREG_R1 == __builtin_offsetof(smc_ctx_t, r1), \ + assert_smc_ctx_greg_r1_offset_mismatch); +CASSERT(SMC_CTX_GPREG_R2 == __builtin_offsetof(smc_ctx_t, r2), \ + assert_smc_ctx_greg_r2_offset_mismatch); +CASSERT(SMC_CTX_GPREG_R3 == __builtin_offsetof(smc_ctx_t, r3), \ + assert_smc_ctx_greg_r3_offset_mismatch); +CASSERT(SMC_CTX_GPREG_R4 == __builtin_offsetof(smc_ctx_t, r4), \ + assert_smc_ctx_greg_r4_offset_mismatch); +CASSERT(SMC_CTX_SP_USR == __builtin_offsetof(smc_ctx_t, sp_usr), \ + assert_smc_ctx_sp_usr_offset_mismatch); +CASSERT(SMC_CTX_LR_MON == __builtin_offsetof(smc_ctx_t, lr_mon), \ + assert_smc_ctx_lr_mon_offset_mismatch); +CASSERT(SMC_CTX_SPSR_MON == __builtin_offsetof(smc_ctx_t, spsr_mon), \ + assert_smc_ctx_spsr_mon_offset_mismatch); + +CASSERT((sizeof(smc_ctx_t) & 0x7U) == 0U, assert_smc_ctx_not_aligned); +CASSERT(SMC_CTX_SIZE == sizeof(smc_ctx_t), assert_smc_ctx_size_mismatch); + +/* Convenience macros to return from SMC handler */ +#define SMC_RET0(_h) { \ + return (uintptr_t)(_h); \ +} +#define SMC_RET1(_h, _r0) { \ + ((smc_ctx_t *)(_h))->r0 = (_r0); \ + SMC_RET0(_h); \ +} +#define SMC_RET2(_h, _r0, _r1) { \ + ((smc_ctx_t *)(_h))->r1 = (_r1); \ + SMC_RET1(_h, (_r0)); \ +} +#define SMC_RET3(_h, _r0, _r1, _r2) { \ + ((smc_ctx_t *)(_h))->r2 = (_r2); \ + SMC_RET2(_h, (_r0), (_r1)); \ +} +#define SMC_RET4(_h, _r0, _r1, _r2, _r3) { \ + ((smc_ctx_t *)(_h))->r3 = (_r3); \ + SMC_RET3(_h, (_r0), (_r1), (_r2)); \ +} +#define SMC_RET5(_h, _r0, _r1, _r2, _r3, _r4) { \ + ((smc_ctx_t *)(_h))->r4 = (_r4); \ + SMC_RET4(_h, (_r0), (_r1), (_r2), (_r3)); \ +} +#define SMC_RET6(_h, _r0, _r1, _r2, _r3, _r4, _r5) { \ + ((smc_ctx_t *)(_h))->r5 = (_r5); \ + SMC_RET5(_h, (_r0), (_r1), (_r2), (_r3), (_r4)); \ +} +#define SMC_RET7(_h, _r0, _r1, _r2, _r3, _r4, _r5, _r6) { \ + ((smc_ctx_t *)(_h))->r6 = (_r6); \ + SMC_RET6(_h, (_r0), (_r1), (_r2), (_r3), (_r4), (_r5)); \ +} +#define SMC_RET8(_h, _r0, _r1, _r2, _r3, _r4, _r5, _r6, _r7) { \ + ((smc_ctx_t *)(_h))->r7 = (_r7); \ + SMC_RET7(_h, (_r0), (_r1), (_r2), (_r3), (_r4), (_r5), (_r6)); \ +} + +/* + * Helper macro to retrieve the SMC parameters from smc_ctx_t. + */ +#define get_smc_params_from_ctx(_hdl, _r1, _r2, _r3, _r4) { \ + _r1 = ((smc_ctx_t *)_hdl)->r1; \ + _r2 = ((smc_ctx_t *)_hdl)->r2; \ + _r3 = ((smc_ctx_t *)_hdl)->r3; \ + _r4 = ((smc_ctx_t *)_hdl)->r4; \ + } + +/* ------------------------------------------------------------------------ + * Helper APIs for setting and retrieving appropriate `smc_ctx_t`. + * These functions need to implemented by the BL including this library. + * ------------------------------------------------------------------------ + */ + +/* Get the pointer to `smc_ctx_t` corresponding to the security state. */ +void *smc_get_ctx(unsigned int security_state); + +/* Set the next `smc_ctx_t` corresponding to the security state. */ +void smc_set_next_ctx(unsigned int security_state); + +/* Get the pointer to next `smc_ctx_t` already set by `smc_set_next_ctx()`. */ +void *smc_get_next_ctx(void); + +#endif /*__ASSEMBLER__*/ + +#endif /* SMCCC_HELPERS_H */ |