/* * Copyright (c) 2006-2018, RT-Thread Development Team * * SPDX-License-Identifier: Apache-2.0 * * Change Logs: * Date Author Notes * 2013-07-05 Bernard the first version * 2018-11-22 Jesven in the interrupt context, use rt_scheduler_do_irq_switch checks * and switches to a new thread */ #include "rtconfig.h" .equ Mode_USR, 0x10 .equ Mode_FIQ, 0x11 .equ Mode_IRQ, 0x12 .equ Mode_SVC, 0x13 .equ Mode_ABT, 0x17 .equ Mode_UND, 0x1B .equ Mode_SYS, 0x1F .equ I_Bit, 0x80 /* when I bit is set, IRQ is disabled */ .equ F_Bit, 0x40 /* when F bit is set, FIQ is disabled */ #ifdef RT_USING_SMART .data .align 14 init_mtbl: .space 16*1024 #endif .text /* reset entry */ .globl _reset _reset: #ifdef ARCH_ARMV8 /* Check for HYP mode */ mrs r0, cpsr_all and r0, r0, #0x1F mov r8, #0x1A cmp r0, r8 beq overHyped b continue overHyped: /* Get out of HYP mode */ adr r1, continue msr ELR_hyp, r1 mrs r1, cpsr_all and r1, r1, #0x1f /* CPSR_MODE_MASK */ orr r1, r1, #0x13 /* CPSR_MODE_SUPERVISOR */ msr SPSR_hyp, r1 eret continue: #endif #ifdef SOC_BCM283x /* Suspend the other cpu cores */ mrc p15, 0, r0, c0, c0, 5 ands r0, #3 bne _halt /* Disable IRQ & FIQ */ cpsid if /* Check for HYP mode */ mrs r0, cpsr_all and r0, r0, #0x1F mov r8, #0x1A cmp r0, r8 beq overHyped b continue overHyped: /* Get out of HYP mode */ adr r1, continue msr ELR_hyp, r1 mrs r1, cpsr_all and r1, r1, #0x1f /* CPSR_MODE_MASK */ orr r1, r1, #0x13 /* CPSR_MODE_SUPERVISOR */ msr SPSR_hyp, r1 eret continue: /* set the cpu to SVC32 mode and disable interrupt */ mrs r0, cpsr bic r0, r0, #0x1f orr r0, r0, #0x13 msr cpsr_c, r0 #endif /* invalid tlb before enable mmu */ mrc p15, 0, r0, c1, c0, 0 bic r0, #1 mcr p15, 0, r0, c1, c0, 0 dsb isb mov r0, #0 mcr p15, 0, r0, c8, c7, 0 mcr p15, 0, r0, c7, c5, 0 /* iciallu */ mcr p15, 0, r0, c7, c5, 6 /* bpiall */ dsb isb #ifdef RT_USING_SMART /* load r5 with PV_OFFSET */ ldr r7, =_reset adr r5, _reset sub r5, r5, r7 mov r7, #0x100000 sub r7, #1 mvn r8, r7 ldr r9, =KERNEL_VADDR_START ldr r6, =__bss_end add r6, r7 and r6, r8 /* r6 end vaddr align up to 1M */ sub r6, r9 /* r6 is size */ ldr sp, =svc_stack_n_limit add sp, r5 /* use paddr */ ldr r0, =init_mtbl add r0, r5 mov r1, r6 mov r2, r5 bl init_mm_setup ldr lr, =after_enable_mmu ldr r0, =init_mtbl add r0, r5 b enable_mmu after_enable_mmu: #endif #ifndef SOC_BCM283x /* set the cpu to SVC32 mode and disable interrupt */ cps #Mode_SVC #endif #ifdef RT_USING_FPU mov r4, #0xfffffff mcr p15, 0, r4, c1, c0, 2 #endif /* disable the data alignment check */ mrc p15, 0, r1, c1, c0, 0 bic r1, #(1<<1) mcr p15, 0, r1, c1, c0, 0 /* enable I cache + branch prediction */ mrc p15, 0, r0, c1, c0, 0 orr r0, r0, #(1<<12) orr r0, r0, #(1<<11) mcr p15, 0, r0, c1, c0, 0 /* setup stack */ bl stack_setup /* clear .bss */ mov r0,#0 /* get a zero */ ldr r1,=__bss_start /* bss start */ ldr r2,=__bss_end /* bss end */ bss_loop: cmp r1,r2 /* check if data to clear */ strlo r0,[r1],#4 /* clear 4 bytes */ blo bss_loop /* loop until done */ mov r0, r5 bl rt_kmem_pvoff_set #ifdef RT_USING_SMP mrc p15, 0, r1, c1, c0, 1 mov r0, #(1<<6) orr r1, r0 mcr p15, 0, r1, c1, c0, 1 /* enable smp */ #endif /** * void rt_hw_init_mmu_table(struct mem_desc *mdesc, rt_uint32_t size) * initialize the mmu table and enable mmu */ ldr r0, =platform_mem_desc ldr r1, =platform_mem_desc_size ldr r1, [r1] bl rt_hw_init_mmu_table #ifdef RT_USING_SMART ldr r0, =MMUTable /* vaddr */ add r0, r5 /* to paddr */ bl rt_hw_mmu_switch #else bl rt_hw_mmu_init #endif /* start RT-Thread Kernel */ ldr pc, _rtthread_startup _rtthread_startup: .word rtthread_startup stack_setup: #ifdef RT_USING_SMP /* cpu id */ mrc p15, 0, r0, c0, c0, 5 and r0, r0, #0xf add r0, r0, #1 #else mov r0, #1 #endif cps #Mode_UND ldr r1, =und_stack_n add sp, r1, r0, asl #12 cps #Mode_IRQ ldr r1, =irq_stack_n add sp, r1, r0, asl #12 cps #Mode_FIQ ldr r1, =irq_stack_n add sp, r1, r0, asl #12 cps #Mode_ABT ldr r1, =abt_stack_n add sp, r1, r0, asl #12 cps #Mode_SVC ldr r1, =svc_stack_n add sp, r1, r0, asl #12 bx lr #ifdef RT_USING_SMART .align 2 .global enable_mmu enable_mmu: orr r0, #0x18 mcr p15, 0, r0, c2, c0, 0 /* ttbr0 */ mov r0, #(1 << 5) /* PD1=1 */ mcr p15, 0, r0, c2, c0, 2 /* ttbcr */ mov r0, #1 mcr p15, 0, r0, c3, c0, 0 /* dacr */ /* invalid tlb before enable mmu */ mov r0, #0 mcr p15, 0, r0, c8, c7, 0 mcr p15, 0, r0, c7, c5, 0 /* iciallu */ mcr p15, 0, r0, c7, c5, 6 /* bpiall */ mrc p15, 0, r0, c1, c0, 0 orr r0, #((1 << 12) | (1 << 11)) /* instruction cache, branch prediction */ orr r0, #((1 << 2) | (1 << 0)) /* data cache, mmu enable */ mcr p15, 0, r0, c1, c0, 0 dsb isb mov pc, lr .global rt_hw_set_process_id rt_hw_set_process_id: LSL r0, r0, #8 MCR p15, 0, r0, c13, c0, 1 mov pc, lr #endif .global rt_hw_mmu_switch rt_hw_mmu_switch: orr r0, #0x18 mcr p15, 0, r0, c2, c0, 0 // ttbr0 //invalid tlb mov r0, #0 mcr p15, 0, r0, c8, c7, 0 mcr p15, 0, r0, c7, c5, 0 //iciallu mcr p15, 0, r0, c7, c5, 6 //bpiall dsb isb mov pc, lr .global rt_hw_mmu_tbl_get rt_hw_mmu_tbl_get: mrc p15, 0, r0, c2, c0, 0 /* ttbr0 */ bic r0, #0x18 mov pc, lr _halt: wfe b _halt /* exception handlers: undef, swi, padt, dabt, resv, irq, fiq */ .section .text.isr, "ax" .align 5 .globl vector_fiq vector_fiq: stmfd sp!,{r0-r7,lr} bl rt_hw_trap_fiq ldmfd sp!,{r0-r7,lr} subs pc, lr, #4 .globl rt_interrupt_enter .globl rt_interrupt_leave .globl rt_thread_switch_interrupt_flag .globl rt_interrupt_from_thread .globl rt_interrupt_to_thread .globl rt_current_thread .globl vmm_thread .globl vmm_virq_check .align 5 .globl vector_irq vector_irq: #ifdef RT_USING_SMP clrex stmfd sp!, {r0, r1} cps #Mode_SVC mov r0, sp /* svc_sp */ mov r1, lr /* svc_lr */ cps #Mode_IRQ sub lr, #4 stmfd r0!, {r1, lr} /* svc_lr, svc_pc */ stmfd r0!, {r2 - r12} ldmfd sp!, {r1, r2} /* original r0, r1 */ stmfd r0!, {r1 - r2} mrs r1, spsr /* original mode */ stmfd r0!, {r1} #ifdef RT_USING_SMART stmfd r0, {r13, r14}^ /* usr_sp, usr_lr */ sub r0, #8 #endif #ifdef RT_USING_FPU /* fpu context */ vmrs r6, fpexc tst r6, #(1<<30) beq 1f vstmdb r0!, {d0-d15} vstmdb r0!, {d16-d31} vmrs r5, fpscr stmfd r0!, {r5} 1: stmfd r0!, {r6} #endif /* now irq stack is clean */ /* r0 is task svc_sp */ /* backup r0 -> r8 */ mov r8, r0 cps #Mode_SVC mov sp, r8 bl rt_interrupt_enter bl rt_hw_trap_irq bl rt_interrupt_leave mov r0, r8 bl rt_scheduler_do_irq_switch b rt_hw_context_switch_exit #else stmfd sp!, {r0-r12,lr} bl rt_interrupt_enter bl rt_hw_trap_irq bl rt_interrupt_leave /* if rt_thread_switch_interrupt_flag set, jump to * rt_hw_context_switch_interrupt_do and don't return */ ldr r0, =rt_thread_switch_interrupt_flag ldr r1, [r0] cmp r1, #1 beq rt_hw_context_switch_interrupt_do #ifdef RT_USING_SMART ldmfd sp!, {r0-r12,lr} cps #Mode_SVC push {r0-r12} mov r7, lr cps #Mode_IRQ mrs r4, spsr sub r5, lr, #4 cps #Mode_SVC and r6, r4, #0x1f cmp r6, #0x10 bne 1f msr spsr_csxf, r4 mov lr, r5 pop {r0-r12} b arch_ret_to_user 1: mov lr, r7 cps #Mode_IRQ msr spsr_csxf, r4 mov lr, r5 cps #Mode_SVC pop {r0-r12} cps #Mode_IRQ movs pc, lr #else ldmfd sp!, {r0-r12,lr} subs pc, lr, #4 #endif rt_hw_context_switch_interrupt_do: mov r1, #0 /* clear flag */ str r1, [r0] mov r1, sp /* r1 point to {r0-r3} in stack */ add sp, sp, #4*4 ldmfd sp!, {r4-r12,lr} /* reload saved registers */ mrs r0, spsr /* get cpsr of interrupt thread */ sub r2, lr, #4 /* save old task's pc to r2 */ /* Switch to SVC mode with no interrupt. If the usr mode guest is * interrupted, this will just switch to the stack of kernel space. * save the registers in kernel space won't trigger data abort. */ msr cpsr_c, #I_Bit|F_Bit|Mode_SVC stmfd sp!, {r2} /* push old task's pc */ stmfd sp!, {r4-r12,lr} /* push old task's lr,r12-r4 */ ldmfd r1, {r1-r4} /* restore r0-r3 of the interrupt thread */ stmfd sp!, {r1-r4} /* push old task's r0-r3 */ stmfd sp!, {r0} /* push old task's cpsr */ #ifdef RT_USING_SMART stmfd sp, {r13, r14}^ /*push usr_sp, usr_lr */ sub sp, #8 #endif #ifdef RT_USING_FPU /* fpu context */ vmrs r6, fpexc tst r6, #(1<<30) beq 1f vstmdb sp!, {d0-d15} vstmdb sp!, {d16-d31} vmrs r5, fpscr stmfd sp!, {r5} 1: stmfd sp!, {r6} #endif ldr r4, =rt_interrupt_from_thread ldr r5, [r4] str sp, [r5] /* store sp in preempted tasks's TCB */ ldr r6, =rt_interrupt_to_thread ldr r6, [r6] ldr sp, [r6] /* get new task's stack pointer */ bl rt_thread_self #ifdef RT_USING_SMART mov r4, r0 bl lwp_aspace_switch mov r0, r4 bl lwp_user_setting_restore #endif #ifdef RT_USING_FPU /* fpu context */ ldmfd sp!, {r6} vmsr fpexc, r6 tst r6, #(1<<30) beq 1f ldmfd sp!, {r5} vmsr fpscr, r5 vldmia sp!, {d16-d31} vldmia sp!, {d0-d15} 1: #endif #ifdef RT_USING_SMART ldmfd sp, {r13, r14}^ /*pop usr_sp, usr_lr */ add sp, #8 #endif ldmfd sp!, {r4} /* pop new task's cpsr to spsr */ msr spsr_cxsf, r4 #ifdef RT_USING_SMART and r4, #0x1f cmp r4, #0x10 bne 1f ldmfd sp!, {r0-r12,lr} ldmfd sp!, {lr} b arch_ret_to_user 1: #endif /* pop new task's r0-r12,lr & pc, copy spsr to cpsr */ ldmfd sp!, {r0-r12,lr,pc}^ #endif .macro push_svc_reg sub sp, sp, #17 * 4 /* Sizeof(struct rt_hw_exp_stack) */ stmia sp, {r0 - r12} /* Calling r0-r12 */ mov r0, sp add sp, sp, #17 * 4 mrs r6, spsr /* Save CPSR */ str lr, [r0, #15*4] /* Push PC */ str r6, [r0, #16*4] /* Push CPSR */ and r1, r6, #0x1f cmp r1, #0x10 cps #Mode_SYS streq sp, [r0, #13*4] /* Save calling SP */ streq lr, [r0, #14*4] /* Save calling PC */ cps #Mode_SVC strne sp, [r0, #13*4] /* Save calling SP */ strne lr, [r0, #14*4] /* Save calling PC */ .endm .align 5 .weak vector_swi vector_swi: push_svc_reg bl rt_hw_trap_swi b . .align 5 .globl vector_undef vector_undef: push_svc_reg bl rt_hw_trap_undef cps #Mode_UND #ifdef RT_USING_FPU sub sp, sp, #17 * 4 ldr lr, [sp, #15*4] ldmia sp, {r0 - r12} add sp, sp, #17 * 4 movs pc, lr #endif b . .align 5 .globl vector_pabt vector_pabt: push_svc_reg #ifdef RT_USING_SMART /* cp Mode_ABT stack to SVC */ sub sp, sp, #17 * 4 /* Sizeof(struct rt_hw_exp_stack) */ mov lr, r0 ldmia lr, {r0 - r12} stmia sp, {r0 - r12} add r1, lr, #13 * 4 add r2, sp, #13 * 4 ldmia r1, {r4 - r7} stmia r2, {r4 - r7} mov r0, sp bl rt_hw_trap_pabt /* return to user */ ldr lr, [sp, #16*4] /* orign spsr */ msr spsr_cxsf, lr ldr lr, [sp, #15*4] /* orign pc */ ldmia sp, {r0 - r12} add sp, #17 * 4 b arch_ret_to_user #else bl rt_hw_trap_pabt b . #endif .align 5 .globl vector_dabt vector_dabt: push_svc_reg #ifdef RT_USING_SMART /* cp Mode_ABT stack to SVC */ sub sp, sp, #17 * 4 /* Sizeof(struct rt_hw_exp_stack) */ mov lr, r0 ldmia lr, {r0 - r12} stmia sp, {r0 - r12} add r1, lr, #13 * 4 add r2, sp, #13 * 4 ldmia r1, {r4 - r7} stmia r2, {r4 - r7} mov r0, sp bl rt_hw_trap_dabt /* return to user */ ldr lr, [sp, #16*4] /* orign spsr */ msr spsr_cxsf, lr ldr lr, [sp, #15*4] /* orign pc */ ldmia sp, {r0 - r12} add sp, #17 * 4 b arch_ret_to_user #else bl rt_hw_trap_dabt b . #endif .align 5 .globl vector_resv vector_resv: push_svc_reg bl rt_hw_trap_resv b . .global rt_hw_clz rt_hw_clz: clz r0, r0 bx lr #ifdef RT_USING_SMP .global rt_secondary_cpu_entry rt_secondary_cpu_entry: #ifdef RT_USING_SMART ldr r0, =_reset adr r5, _reset sub r5, r5, r0 ldr lr, =after_enable_mmu_n ldr r0, =init_mtbl add r0, r5 b enable_mmu after_enable_mmu_n: ldr r0, =MMUTable add r0, r5 bl rt_hw_mmu_switch #endif #ifdef RT_USING_FPU mov r4, #0xfffffff mcr p15, 0, r4, c1, c0, 2 #endif mrc p15, 0, r1, c1, c0, 1 mov r0, #(1<<6) orr r1, r0 mcr p15, 0, r1, c1, c0, 1 /* enable smp */ mrc p15, 0, r0, c1, c0, 0 bic r0, #(1<<13) mcr p15, 0, r0, c1, c0, 0 bl stack_setup /* initialize the mmu table and enable mmu */ #ifndef RT_USING_SMART bl rt_hw_mmu_init #endif b rt_hw_secondary_cpu_bsp_start #endif #ifndef RT_CPUS_NR #define RT_CPUS_NR 1 #endif .bss .align 3 /* align to 2~3=8 */ svc_stack_n: .space (RT_CPUS_NR << 12) svc_stack_n_limit: irq_stack_n: .space (RT_CPUS_NR << 12) und_stack_n: .space (RT_CPUS_NR << 12) abt_stack_n: .space (RT_CPUS_NR << 12)