| /* |
| * Copyright (c) 2013-2014, ARM Limited and Contributors. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are met: |
| * |
| * Redistributions of source code must retain the above copyright notice, this |
| * list of conditions and the following disclaimer. |
| * |
| * Redistributions in binary form must reproduce the above copyright notice, |
| * this list of conditions and the following disclaimer in the documentation |
| * and/or other materials provided with the distribution. |
| * |
| * Neither the name of ARM nor the names of its contributors may be used |
| * to endorse or promote products derived from this software without specific |
| * prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
| * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE |
| * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| * POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include <arch.h> |
| #include <asm_macros.S> |
| #include <context.h> |
| #include <interrupt_mgmt.h> |
| #include <platform_def.h> |
| #include <runtime_svc.h> |
| |
| .globl runtime_exceptions |
| .globl el3_exit |
| |
| /* ----------------------------------------------------- |
| * Handle SMC exceptions separately from other sync. |
| * exceptions. |
| * ----------------------------------------------------- |
| */ |
| .macro handle_sync_exception |
| /* Enable the SError interrupt */ |
| msr daifclr, #DAIF_ABT_BIT |
| |
| str x30, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_LR] |
| mrs x30, esr_el3 |
| ubfx x30, x30, #ESR_EC_SHIFT, #ESR_EC_LENGTH |
| |
| cmp x30, #EC_AARCH32_SMC |
| b.eq smc_handler32 |
| |
| cmp x30, #EC_AARCH64_SMC |
| b.eq smc_handler64 |
| |
| /* ----------------------------------------------------- |
| * The following code handles any synchronous exception |
| * that is not an SMC. |
| * ----------------------------------------------------- |
| */ |
| |
| bl report_unhandled_exception |
| .endm |
| |
| |
| /* ----------------------------------------------------- |
| * This macro handles FIQ or IRQ interrupts i.e. EL3, |
| * S-EL1 and NS interrupts. |
| * ----------------------------------------------------- |
| */ |
| .macro handle_interrupt_exception label |
| /* Enable the SError interrupt */ |
| msr daifclr, #DAIF_ABT_BIT |
| |
| str x30, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_LR] |
| bl save_gp_registers |
| |
| /* Switch to the runtime stack i.e. SP_EL0 */ |
| ldr x2, [sp, #CTX_EL3STATE_OFFSET + CTX_RUNTIME_SP] |
| mov x20, sp |
| msr spsel, #0 |
| mov sp, x2 |
| |
| /* |
| * Find out whether this is a valid interrupt type. If the |
| * interrupt controller reports a spurious interrupt then |
| * return to where we came from. |
| */ |
| bl plat_ic_get_pending_interrupt_type |
| cmp x0, #INTR_TYPE_INVAL |
| b.eq interrupt_exit_\label |
| |
| /* |
| * Get the registered handler for this interrupt type. A |
| * NULL return value implies that an interrupt was generated |
| * for which there is no handler registered or the interrupt |
| * was routed incorrectly. This is a problem of the framework |
| * so report it as an error. |
| */ |
| bl get_interrupt_type_handler |
| cbz x0, interrupt_error_\label |
| mov x21, x0 |
| |
| mov x0, #INTR_ID_UNAVAILABLE |
| #if IMF_READ_INTERRUPT_ID |
| /* |
| * Read the id of the highest priority pending interrupt. If |
| * no interrupt is asserted then return to where we came from. |
| */ |
| mov x19, #INTR_ID_UNAVAILABLE |
| bl plat_ic_get_pending_interrupt_id |
| cmp x19, x0 |
| b.eq interrupt_exit_\label |
| #endif |
| |
| /* |
| * Save the EL3 system registers needed to return from |
| * this exception. |
| */ |
| mrs x3, spsr_el3 |
| mrs x4, elr_el3 |
| stp x3, x4, [x20, #CTX_EL3STATE_OFFSET + CTX_SPSR_EL3] |
| |
| /* Set the current security state in the 'flags' parameter */ |
| mrs x2, scr_el3 |
| ubfx x1, x2, #0, #1 |
| |
| /* Restore the reference to the 'handle' i.e. SP_EL3 */ |
| mov x2, x20 |
| |
| /* x3 will point to a cookie (not used now) */ |
| mov x3, xzr |
| |
| /* Call the interrupt type handler */ |
| blr x21 |
| |
| interrupt_exit_\label: |
| /* Return from exception, possibly in a different security state */ |
| b el3_exit |
| |
| /* |
| * This label signifies a problem with the interrupt management |
| * framework where it is not safe to go back to the instruction |
| * where the interrupt was generated. |
| */ |
| interrupt_error_\label: |
| bl report_unhandled_interrupt |
| .endm |
| |
| |
| .macro save_x18_to_x29_sp_el0 |
| stp x18, x19, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X18] |
| stp x20, x21, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X20] |
| stp x22, x23, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X22] |
| stp x24, x25, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X24] |
| stp x26, x27, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X26] |
| stp x28, x29, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X28] |
| mrs x18, sp_el0 |
| str x18, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_SP_EL0] |
| .endm |
| |
| .section .vectors, "ax"; .align 11 |
| .align 7 |
| runtime_exceptions: |
| /* ----------------------------------------------------- |
| * Current EL with _sp_el0 : 0x0 - 0x200 |
| * ----------------------------------------------------- |
| */ |
| sync_exception_sp_el0: |
| /* ----------------------------------------------------- |
| * We don't expect any synchronous exceptions from EL3 |
| * ----------------------------------------------------- |
| */ |
| bl report_unhandled_exception |
| check_vector_size sync_exception_sp_el0 |
| |
| .align 7 |
| /* ----------------------------------------------------- |
| * EL3 code is non-reentrant. Any asynchronous exception |
| * is a serious error. Loop infinitely. |
| * ----------------------------------------------------- |
| */ |
| irq_sp_el0: |
| bl report_unhandled_interrupt |
| check_vector_size irq_sp_el0 |
| |
| .align 7 |
| fiq_sp_el0: |
| bl report_unhandled_interrupt |
| check_vector_size fiq_sp_el0 |
| |
| .align 7 |
| serror_sp_el0: |
| bl report_unhandled_exception |
| check_vector_size serror_sp_el0 |
| |
| /* ----------------------------------------------------- |
| * Current EL with SPx: 0x200 - 0x400 |
| * ----------------------------------------------------- |
| */ |
| .align 7 |
| sync_exception_sp_elx: |
| /* ----------------------------------------------------- |
| * This exception will trigger if anything went wrong |
| * during a previous exception entry or exit or while |
| * handling an earlier unexpected synchronous exception. |
| * There is a high probability that SP_EL3 is corrupted. |
| * ----------------------------------------------------- |
| */ |
| bl report_unhandled_exception |
| check_vector_size sync_exception_sp_elx |
| |
| .align 7 |
| irq_sp_elx: |
| bl report_unhandled_interrupt |
| check_vector_size irq_sp_elx |
| |
| .align 7 |
| fiq_sp_elx: |
| bl report_unhandled_interrupt |
| check_vector_size fiq_sp_elx |
| |
| .align 7 |
| serror_sp_elx: |
| bl report_unhandled_exception |
| check_vector_size serror_sp_elx |
| |
| /* ----------------------------------------------------- |
| * Lower EL using AArch64 : 0x400 - 0x600 |
| * ----------------------------------------------------- |
| */ |
| .align 7 |
| sync_exception_aarch64: |
| /* ----------------------------------------------------- |
| * This exception vector will be the entry point for |
| * SMCs and traps that are unhandled at lower ELs most |
| * commonly. SP_EL3 should point to a valid cpu context |
| * where the general purpose and system register state |
| * can be saved. |
| * ----------------------------------------------------- |
| */ |
| handle_sync_exception |
| check_vector_size sync_exception_aarch64 |
| |
| .align 7 |
| /* ----------------------------------------------------- |
| * Asynchronous exceptions from lower ELs are not |
| * currently supported. Report their occurrence. |
| * ----------------------------------------------------- |
| */ |
| irq_aarch64: |
| handle_interrupt_exception irq_aarch64 |
| check_vector_size irq_aarch64 |
| |
| .align 7 |
| fiq_aarch64: |
| handle_interrupt_exception fiq_aarch64 |
| check_vector_size fiq_aarch64 |
| |
| .align 7 |
| serror_aarch64: |
| bl report_unhandled_exception |
| check_vector_size serror_aarch64 |
| |
| /* ----------------------------------------------------- |
| * Lower EL using AArch32 : 0x600 - 0x800 |
| * ----------------------------------------------------- |
| */ |
| .align 7 |
| sync_exception_aarch32: |
| /* ----------------------------------------------------- |
| * This exception vector will be the entry point for |
| * SMCs and traps that are unhandled at lower ELs most |
| * commonly. SP_EL3 should point to a valid cpu context |
| * where the general purpose and system register state |
| * can be saved. |
| * ----------------------------------------------------- |
| */ |
| handle_sync_exception |
| check_vector_size sync_exception_aarch32 |
| |
| .align 7 |
| /* ----------------------------------------------------- |
| * Asynchronous exceptions from lower ELs are not |
| * currently supported. Report their occurrence. |
| * ----------------------------------------------------- |
| */ |
| irq_aarch32: |
| handle_interrupt_exception irq_aarch32 |
| check_vector_size irq_aarch32 |
| |
| .align 7 |
| fiq_aarch32: |
| handle_interrupt_exception fiq_aarch32 |
| check_vector_size fiq_aarch32 |
| |
| .align 7 |
| serror_aarch32: |
| bl report_unhandled_exception |
| check_vector_size serror_aarch32 |
| |
| .align 7 |
| |
| /* ----------------------------------------------------- |
| * The following code handles secure monitor calls. |
| * Depending upon the execution state from where the SMC |
| * has been invoked, it frees some general purpose |
| * registers to perform the remaining tasks. They |
| * involve finding the runtime service handler that is |
| * the target of the SMC & switching to runtime stacks |
| * (SP_EL0) before calling the handler. |
| * |
| * Note that x30 has been explicitly saved and can be |
| * used here |
| * ----------------------------------------------------- |
| */ |
| func smc_handler |
| smc_handler32: |
| /* Check whether aarch32 issued an SMC64 */ |
| tbnz x0, #FUNCID_CC_SHIFT, smc_prohibited |
| |
| /* ----------------------------------------------------- |
| * Since we're are coming from aarch32, x8-x18 need to |
| * be saved as per SMC32 calling convention. If a lower |
| * EL in aarch64 is making an SMC32 call then it must |
| * have saved x8-x17 already therein. |
| * ----------------------------------------------------- |
| */ |
| stp x8, x9, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X8] |
| stp x10, x11, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X10] |
| stp x12, x13, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X12] |
| stp x14, x15, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X14] |
| stp x16, x17, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X16] |
| |
| /* x4-x7, x18, sp_el0 are saved below */ |
| |
| smc_handler64: |
| /* ----------------------------------------------------- |
| * Populate the parameters for the SMC handler. We |
| * already have x0-x4 in place. x5 will point to a |
| * cookie (not used now). x6 will point to the context |
| * structure (SP_EL3) and x7 will contain flags we need |
| * to pass to the handler Hence save x5-x7. Note that x4 |
| * only needs to be preserved for AArch32 callers but we |
| * do it for AArch64 callers as well for convenience |
| * ----------------------------------------------------- |
| */ |
| stp x4, x5, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X4] |
| stp x6, x7, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X6] |
| |
| /* Save rest of the gpregs and sp_el0*/ |
| save_x18_to_x29_sp_el0 |
| |
| mov x5, xzr |
| mov x6, sp |
| |
| /* Get the unique owning entity number */ |
| ubfx x16, x0, #FUNCID_OEN_SHIFT, #FUNCID_OEN_WIDTH |
| ubfx x15, x0, #FUNCID_TYPE_SHIFT, #FUNCID_TYPE_WIDTH |
| orr x16, x16, x15, lsl #FUNCID_OEN_WIDTH |
| |
| adr x11, (__RT_SVC_DESCS_START__ + RT_SVC_DESC_HANDLE) |
| |
| /* Load descriptor index from array of indices */ |
| adr x14, rt_svc_descs_indices |
| ldrb w15, [x14, x16] |
| |
| /* ----------------------------------------------------- |
| * Restore the saved C runtime stack value which will |
| * become the new SP_EL0 i.e. EL3 runtime stack. It was |
| * saved in the 'cpu_context' structure prior to the last |
| * ERET from EL3. |
| * ----------------------------------------------------- |
| */ |
| ldr x12, [x6, #CTX_EL3STATE_OFFSET + CTX_RUNTIME_SP] |
| |
| /* |
| * Any index greater than 127 is invalid. Check bit 7 for |
| * a valid index |
| */ |
| tbnz w15, 7, smc_unknown |
| |
| /* Switch to SP_EL0 */ |
| msr spsel, #0 |
| |
| /* ----------------------------------------------------- |
| * Get the descriptor using the index |
| * x11 = (base + off), x15 = index |
| * |
| * handler = (base + off) + (index << log2(size)) |
| * ----------------------------------------------------- |
| */ |
| lsl w10, w15, #RT_SVC_SIZE_LOG2 |
| ldr x15, [x11, w10, uxtw] |
| |
| /* ----------------------------------------------------- |
| * Save the SPSR_EL3, ELR_EL3, & SCR_EL3 in case there |
| * is a world switch during SMC handling. |
| * TODO: Revisit if all system registers can be saved |
| * later. |
| * ----------------------------------------------------- |
| */ |
| mrs x16, spsr_el3 |
| mrs x17, elr_el3 |
| mrs x18, scr_el3 |
| stp x16, x17, [x6, #CTX_EL3STATE_OFFSET + CTX_SPSR_EL3] |
| str x18, [x6, #CTX_EL3STATE_OFFSET + CTX_SCR_EL3] |
| |
| /* Copy SCR_EL3.NS bit to the flag to indicate caller's security */ |
| bfi x7, x18, #0, #1 |
| |
| mov sp, x12 |
| |
| /* ----------------------------------------------------- |
| * Call the Secure Monitor Call handler and then drop |
| * directly into el3_exit() which will program any |
| * remaining architectural state prior to issuing the |
| * ERET to the desired lower EL. |
| * ----------------------------------------------------- |
| */ |
| #if DEBUG |
| cbz x15, rt_svc_fw_critical_error |
| #endif |
| blr x15 |
| |
| /* ----------------------------------------------------- |
| * This routine assumes that the SP_EL3 is pointing to |
| * a valid context structure from where the gp regs and |
| * other special registers can be retrieved. |
| * |
| * Keep it in the same section as smc_handler as this |
| * function uses a fall-through to el3_exit |
| * ----------------------------------------------------- |
| */ |
| el3_exit: ; .type el3_exit, %function |
| /* ----------------------------------------------------- |
| * Save the current SP_EL0 i.e. the EL3 runtime stack |
| * which will be used for handling the next SMC. Then |
| * switch to SP_EL3 |
| * ----------------------------------------------------- |
| */ |
| mov x17, sp |
| msr spsel, #1 |
| str x17, [sp, #CTX_EL3STATE_OFFSET + CTX_RUNTIME_SP] |
| |
| /* ----------------------------------------------------- |
| * Restore SPSR_EL3, ELR_EL3 and SCR_EL3 prior to ERET |
| * ----------------------------------------------------- |
| */ |
| ldr x18, [sp, #CTX_EL3STATE_OFFSET + CTX_SCR_EL3] |
| ldp x16, x17, [sp, #CTX_EL3STATE_OFFSET + CTX_SPSR_EL3] |
| msr scr_el3, x18 |
| msr spsr_el3, x16 |
| msr elr_el3, x17 |
| |
| /* Restore saved general purpose registers and return */ |
| b restore_gp_registers_eret |
| |
| smc_unknown: |
| /* |
| * Here we restore x4-x18 regardless of where we came from. AArch32 |
| * callers will find the registers contents unchanged, but AArch64 |
| * callers will find the registers modified (with stale earlier NS |
| * content). Either way, we aren't leaking any secure information |
| * through them |
| */ |
| mov w0, #SMC_UNK |
| b restore_gp_registers_callee_eret |
| |
| smc_prohibited: |
| ldr x30, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_LR] |
| mov w0, #SMC_UNK |
| eret |
| |
| rt_svc_fw_critical_error: |
| msr spsel, #1 /* Switch to SP_ELx */ |
| bl report_unhandled_exception |
| |
| /* ----------------------------------------------------- |
| * The following functions are used to saved and restore |
| * all the general pupose registers. Ideally we would |
| * only save and restore the callee saved registers when |
| * a world switch occurs but that type of implementation |
| * is more complex. So currently we will always save and |
| * restore these registers on entry and exit of EL3. |
| * These are not macros to ensure their invocation fits |
| * within the 32 instructions per exception vector. |
| * ----------------------------------------------------- |
| */ |
| func save_gp_registers |
| stp x0, x1, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X0] |
| stp x2, x3, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X2] |
| stp x4, x5, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X4] |
| stp x6, x7, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X6] |
| stp x8, x9, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X8] |
| stp x10, x11, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X10] |
| stp x12, x13, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X12] |
| stp x14, x15, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X14] |
| stp x16, x17, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X16] |
| save_x18_to_x29_sp_el0 |
| ret |
| |
| func restore_gp_registers_eret |
| ldp x0, x1, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X0] |
| ldp x2, x3, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X2] |
| |
| restore_gp_registers_callee_eret: |
| ldp x4, x5, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X4] |
| ldp x6, x7, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X6] |
| ldp x8, x9, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X8] |
| ldp x10, x11, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X10] |
| ldp x12, x13, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X12] |
| ldp x14, x15, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X14] |
| ldp x18, x19, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X18] |
| ldp x20, x21, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X20] |
| ldp x22, x23, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X22] |
| ldp x24, x25, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X24] |
| ldp x26, x27, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X26] |
| ldp x28, x29, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X28] |
| ldp x30, x17, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_LR] |
| msr sp_el0, x17 |
| ldp x16, x17, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X16] |
| eret |