/* * 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 #include #include #include .globl tsp_entrypoint .globl tsp_vector_table /* --------------------------------------------- * Populate the params in x0-x7 from the pointer * to the smc args structure in x0. * --------------------------------------------- */ .macro restore_args_call_smc ldp x6, x7, [x0, #TSP_ARG6] ldp x4, x5, [x0, #TSP_ARG4] ldp x2, x3, [x0, #TSP_ARG2] ldp x0, x1, [x0, #TSP_ARG0] smc #0 .endm .macro save_eret_context reg1 reg2 mrs \reg1, elr_el1 mrs \reg2, spsr_el1 stp \reg1, \reg2, [sp, #-0x10]! stp x30, x18, [sp, #-0x10]! .endm .macro restore_eret_context reg1 reg2 ldp x30, x18, [sp], #0x10 ldp \reg1, \reg2, [sp], #0x10 msr elr_el1, \reg1 msr spsr_el1, \reg2 .endm .section .text, "ax" .align 3 func tsp_entrypoint /* --------------------------------------------- * Set the exception vector to something sane. * --------------------------------------------- */ adr x0, tsp_exceptions msr vbar_el1, x0 /* --------------------------------------------- * Enable the instruction cache, stack pointer * and data access alignment checks * --------------------------------------------- */ mov x1, #(SCTLR_I_BIT | SCTLR_A_BIT | SCTLR_SA_BIT) mrs x0, sctlr_el1 orr x0, x0, x1 msr sctlr_el1, x0 isb /* --------------------------------------------- * Zero out NOBITS sections. There are 2 of them: * - the .bss section; * - the coherent memory section. * --------------------------------------------- */ ldr x0, =__BSS_START__ ldr x1, =__BSS_SIZE__ bl zeromem16 ldr x0, =__COHERENT_RAM_START__ ldr x1, =__COHERENT_RAM_UNALIGNED_SIZE__ bl zeromem16 /* -------------------------------------------- * Allocate a stack whose memory will be marked * as Normal-IS-WBWA when the MMU is enabled. * There is no risk of reading stale stack * memory after enabling the MMU as only the * primary cpu is running at the moment. * -------------------------------------------- */ mrs x0, mpidr_el1 bl platform_set_stack /* --------------------------------------------- * Perform early platform setup & platform * specific early arch. setup e.g. mmu setup * --------------------------------------------- */ bl bl32_early_platform_setup bl bl32_plat_arch_setup /* --------------------------------------------- * Jump to main function. * --------------------------------------------- */ bl tsp_main /* --------------------------------------------- * Tell TSPD that we are done initialising * --------------------------------------------- */ mov x1, x0 mov x0, #TSP_ENTRY_DONE smc #0 tsp_entrypoint_panic: b tsp_entrypoint_panic /* ------------------------------------------- * Table of entrypoint vectors provided to the * TSPD for the various entrypoints * ------------------------------------------- */ func tsp_vector_table b tsp_std_smc_entry b tsp_fast_smc_entry b tsp_cpu_on_entry b tsp_cpu_off_entry b tsp_cpu_resume_entry b tsp_cpu_suspend_entry b tsp_fiq_entry /*--------------------------------------------- * This entrypoint is used by the TSPD when this * cpu is to be turned off through a CPU_OFF * psci call to ask the TSP to perform any * bookeeping necessary. In the current * implementation, the TSPD expects the TSP to * re-initialise its state so nothing is done * here except for acknowledging the request. * --------------------------------------------- */ func tsp_cpu_off_entry bl tsp_cpu_off_main restore_args_call_smc /*--------------------------------------------- * This entrypoint is used by the TSPD when this * cpu is turned on using a CPU_ON psci call to * ask the TSP to initialise itself i.e. setup * the mmu, stacks etc. Minimal architectural * state will be initialised by the TSPD when * this function is entered i.e. Caches and MMU * will be turned off, the execution state * will be aarch64 and exceptions masked. * --------------------------------------------- */ func tsp_cpu_on_entry /* --------------------------------------------- * Set the exception vector to something sane. * --------------------------------------------- */ adr x0, tsp_exceptions msr vbar_el1, x0 /* --------------------------------------------- * Enable the instruction cache, stack pointer * and data access alignment checks * --------------------------------------------- */ mov x1, #(SCTLR_I_BIT | SCTLR_A_BIT | SCTLR_SA_BIT) mrs x0, sctlr_el1 orr x0, x0, x1 msr sctlr_el1, x0 isb /* -------------------------------------------- * Give ourselves a stack whose memory will be * marked as Normal-IS-WBWA when the MMU is * enabled. * -------------------------------------------- */ mrs x0, mpidr_el1 bl platform_set_stack /* -------------------------------------------- * Enable the MMU with the DCache disabled. It * is safe to use stacks allocated in normal * memory as a result. All memory accesses are * marked nGnRnE when the MMU is disabled. So * all the stack writes will make it to memory. * All memory accesses are marked Non-cacheable * when the MMU is enabled but D$ is disabled. * So used stack memory is guaranteed to be * visible immediately after the MMU is enabled * Enabling the DCache at the same time as the * MMU can lead to speculatively fetched and * possibly stale stack memory being read from * other caches. This can lead to coherency * issues. * -------------------------------------------- */ mov x0, #DISABLE_DCACHE bl bl32_plat_enable_mmu /* --------------------------------------------- * Enable the Data cache now that the MMU has * been enabled. The stack has been unwound. It * will be written first before being read. This * will invalidate any stale cache lines resi- * -dent in other caches. We assume that * interconnect coherency has been enabled for * this cluster by EL3 firmware. * --------------------------------------------- */ mrs x0, sctlr_el1 orr x0, x0, #SCTLR_C_BIT msr sctlr_el1, x0 isb /* --------------------------------------------- * Enter C runtime to perform any remaining * book keeping * --------------------------------------------- */ bl tsp_cpu_on_main restore_args_call_smc /* Should never reach here */ tsp_cpu_on_entry_panic: b tsp_cpu_on_entry_panic /*--------------------------------------------- * This entrypoint is used by the TSPD when this * cpu is to be suspended through a CPU_SUSPEND * psci call to ask the TSP to perform any * bookeeping necessary. In the current * implementation, the TSPD saves and restores * the EL1 state. * --------------------------------------------- */ func tsp_cpu_suspend_entry bl tsp_cpu_suspend_main restore_args_call_smc /*--------------------------------------------- * This entrypoint is used by the TSPD to pass * control for handling a pending S-EL1 FIQ. * 'x0' contains a magic number which indicates * this. TSPD expects control to be handed back * at the end of FIQ processing. This is done * through an SMC. The handover agreement is: * * 1. PSTATE.DAIF are set upon entry. 'x1' has * the ELR_EL3 from the non-secure state. * 2. TSP has to preserve the callee saved * general purpose registers, SP_EL1/EL0 and * LR. * 3. TSP has to preserve the system and vfp * registers (if applicable). * 4. TSP can use 'x0-x18' to enable its C * runtime. * 5. TSP returns to TSPD using an SMC with * 'x0' = TSP_HANDLED_S_EL1_FIQ * --------------------------------------------- */ func tsp_fiq_entry #if DEBUG mov x2, #(TSP_HANDLE_FIQ_AND_RETURN & ~0xffff) movk x2, #(TSP_HANDLE_FIQ_AND_RETURN & 0xffff) cmp x0, x2 b.ne tsp_fiq_entry_panic #endif /*--------------------------------------------- * Save any previous context needed to perform * an exception return from S-EL1 e.g. context * from a previous IRQ. Update statistics and * handle the FIQ before returning to the TSPD. * IRQ/FIQs are not enabled since that will * complicate the implementation. Execution * will be transferred back to the normal world * in any case. A non-zero return value from the * fiq handler is an error. * --------------------------------------------- */ save_eret_context x2 x3 bl tsp_update_sync_fiq_stats bl tsp_fiq_handler cbnz x0, tsp_fiq_entry_panic restore_eret_context x2 x3 mov x0, #(TSP_HANDLED_S_EL1_FIQ & ~0xffff) movk x0, #(TSP_HANDLED_S_EL1_FIQ & 0xffff) smc #0 tsp_fiq_entry_panic: b tsp_fiq_entry_panic /*--------------------------------------------- * This entrypoint is used by the TSPD when this * cpu resumes execution after an earlier * CPU_SUSPEND psci call to ask the TSP to * restore its saved context. In the current * implementation, the TSPD saves and restores * EL1 state so nothing is done here apart from * acknowledging the request. * --------------------------------------------- */ func tsp_cpu_resume_entry bl tsp_cpu_resume_main restore_args_call_smc tsp_cpu_resume_panic: b tsp_cpu_resume_panic /*--------------------------------------------- * This entrypoint is used by the TSPD to ask * the TSP to service a fast smc request. * --------------------------------------------- */ func tsp_fast_smc_entry bl tsp_smc_handler restore_args_call_smc tsp_fast_smc_entry_panic: b tsp_fast_smc_entry_panic /*--------------------------------------------- * This entrypoint is used by the TSPD to ask * the TSP to service a std smc request. * We will enable preemption during execution * of tsp_smc_handler. * --------------------------------------------- */ func tsp_std_smc_entry msr daifclr, #DAIF_FIQ_BIT | DAIF_IRQ_BIT bl tsp_smc_handler msr daifset, #DAIF_FIQ_BIT | DAIF_IRQ_BIT restore_args_call_smc tsp_std_smc_entry_panic: b tsp_std_smc_entry_panic