/*- * Copyright 2004-2014 Olivier Houchard * Copyright 2012-2014 Ian Lepore * Copyright 2013-2014 Andrew Turner * Copyright 2014 Svatopluk Kraus * Copyright 2014 Michal Meloun * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. 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. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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 "assym.s" #include #include #include #include #include #include #include __FBSDID("$FreeBSD: head/sys/arm/arm/locore-v6.S 300701 2016-05-26 00:03:23Z ian $"); #if __ARM_ARCH >= 7 #if defined(__ARM_ARCH_7VE__) || defined(__clang__) /* * HYP support is in bintuils >= 2.21 and gcc >= 4.9 defines __ARM_ARCH_7VE__ * when enabled. llvm >= 3.6 supports it too. */ .arch_extension virt #define MSR_ELR_HYP(regnum) msr elr_hyp, lr #define ERET eret #else #define MSR_ELR_HYP(regnum) .word (0xe12ef300 | regnum) #define ERET .word 0xe160006e #endif #endif /* __ARM_ARCH >= 7 */ /* A small statically-allocated stack used only during initarm() and AP startup. */ #define INIT_ARM_STACK_SIZE 2048 .text .align 2 #if __ARM_ARCH >= 7 #define HANDLE_HYP \ /* Leave HYP mode */ ;\ mrs r0, cpsr ;\ and r0, r0, #(PSR_MODE) /* Mode is in the low 5 bits of CPSR */ ;\ teq r0, #(PSR_HYP32_MODE) /* Hyp Mode? */ ;\ bne 1f ;\ /* Install Hypervisor Stub Exception Vector */ ;\ bl hypervisor_stub_vect_install ;\ mov r0, 0 ;\ adr r1, hypmode_enabled ;\ str r0, [r1] ;\ /* Ensure that IRQ, FIQ and Aborts will be disabled after eret */ ;\ mrs r0, cpsr ;\ bic r0, r0, #(PSR_MODE) ;\ orr r0, r0, #(PSR_SVC32_MODE) ;\ orr r0, r0, #(PSR_I | PSR_F | PSR_A) ;\ msr spsr_cxsf, r0 ;\ /* Exit hypervisor mode */ ;\ adr lr, 2f ;\ MSR_ELR_HYP(14) ;\ ERET ;\ 1: ;\ mov r0, -1 ;\ adr r1, hypmode_enabled ;\ str r0, [r1] ;\ 2: #else #define HANDLE_HYP #endif /* __ARM_ARCH >= 7 */ /* * On entry for FreeBSD boot ABI: * r0 - metadata pointer or 0 (boothowto on AT91's boot2) * r1 - if (r0 == 0) then metadata pointer * On entry for Linux boot ABI: * r0 - 0 * r1 - machine type (passed as arg2 to initarm) * r2 - Pointer to a tagged list or dtb image (phys addr) (passed as arg1 initarm) * * For both types of boot we gather up the args, put them in a struct arm_boot_params * structure and pass that to initarm. */ .globl btext btext: ASENTRY_NP(_start) STOP_UNWINDING /* Can't unwind into the bootloader! */ mov r8, r0 /* 0 or boot mode from boot2 */ mov r9, r1 /* Save Machine type */ mov r10, r2 /* Save meta data */ mov r11, r3 /* Future expansion */ # If HYP-MODE is active, install an exception vector stub HANDLE_HYP /* * Check whether data cache is enabled. If it is, then we know * current tags are valid (not power-on garbage values) and there * might be dirty lines that need cleaning. Disable cache to prevent * new lines being allocated, then call wbinv_poc_all to clean it. */ mrc CP15_SCTLR(r7) tst r7, #CPU_CONTROL_DC_ENABLE blne dcache_wbinv_poc_all /* ! Do not write to memory between wbinv and disabling cache ! */ /* * Now there are no dirty lines, but there may still be lines marked * valid. Disable all caches and the MMU, and invalidate everything * before setting up new page tables and re-enabling the mmu. */ 1: bic r7, #CPU_CONTROL_DC_ENABLE bic r7, #CPU_CONTROL_AFLT_ENABLE bic r7, #CPU_CONTROL_MMU_ENABLE bic r7, #CPU_CONTROL_IC_ENABLE bic r7, #CPU_CONTROL_BPRD_ENABLE bic r7, #CPU_CONTROL_SW_ENABLE orr r7, #CPU_CONTROL_UNAL_ENABLE orr r7, #CPU_CONTROL_VECRELOC mcr CP15_SCTLR(r7) DSB ISB bl dcache_inv_poc_all mcr CP15_ICIALLU DSB ISB /* * Build page table from scratch. */ /* * Figure out the physical address we're loaded at by assuming this * entry point code is in the first L1 section and so if we clear the * offset bits of the pc that will give us the section-aligned load * address, which remains in r5 throughout all the following code. */ ldr r2, =(L1_S_OFFSET) bic r5, pc, r2 /* Find the delta between VA and PA, result stays in r0 throughout. */ adr r0, Lpagetable bl translate_va_to_pa /* * First map the entire 4GB address space as VA=PA. It's mapped as * normal (cached) memory because it's for things like accessing the * parameters passed in from the bootloader, which might be at any * physical address, different for every platform. */ mov r1, #0 mov r2, #0 mov r3, #4096 bl build_pagetables /* * Next we do 64MiB starting at the physical load address, mapped to * the VA the kernel is linked for. */ mov r1, r5 ldr r2, =(KERNVIRTADDR) mov r3, #64 bl build_pagetables /* Create a device mapping for early_printf if specified. */ #if defined(SOCDEV_PA) && defined(SOCDEV_VA) ldr r1, =SOCDEV_PA ldr r2, =SOCDEV_VA mov r3, #1 bl build_device_pagetables #endif bl init_mmu /* Transition the PC from physical to virtual addressing. */ ldr pc, =1f 1: /* Setup stack, clear BSS */ ldr r1, =.Lstart ldmia r1, {r1, r2, sp} /* Set initial stack and */ add sp, sp, #INIT_ARM_STACK_SIZE sub r2, r2, r1 /* get zero init data */ mov r3, #0 2: str r3, [r1], #0x0004 /* get zero init data */ subs r2, r2, #4 bgt 2b mov r1, #28 /* loader info size is 28 bytes also second arg */ subs sp, sp, r1 /* allocate arm_boot_params struct on stack */ mov r0, sp /* loader info pointer is first arg */ bic sp, sp, #7 /* align stack to 8 bytes */ str r1, [r0] /* Store length of loader info */ str r8, [r0, #4] /* Store r0 from boot loader */ str r9, [r0, #8] /* Store r1 from boot loader */ str r10, [r0, #12] /* store r2 from boot loader */ str r11, [r0, #16] /* store r3 from boot loader */ str r5, [r0, #20] /* store the physical address */ adr r4, Lpagetable /* load the pagetable address */ ldr r5, [r4, #4] str r5, [r0, #24] /* store the pagetable address */ mov fp, #0 /* trace back starts here */ bl _C_LABEL(initarm) /* Off we go */ /* init arm will return the new stack pointer. */ mov sp, r0 bl _C_LABEL(mi_startup) /* call mi_startup()! */ ldr r0, =.Lmainreturned b _C_LABEL(panic) /* NOTREACHED */ END(_start) #define VA_TO_PA_POINTER(name, table) \ name: ;\ .word . ;\ .word table /* * Returns the physical address of a magic va to pa pointer. * r0 - The pagetable data pointer. This must be built using the * VA_TO_PA_POINTER macro. * e.g. * VA_TO_PA_POINTER(Lpagetable, pagetable) * ... * adr r0, Lpagetable * bl translate_va_to_pa * r0 will now contain the physical address of pagetable * r1, r2 - Trashed */ translate_va_to_pa: ldr r1, [r0] sub r2, r1, r0 /* At this point: r2 = VA - PA */ /* * Find the physical address of the table. After these two * instructions: * r1 = va(pagetable) * * r0 = va(pagetable) - (VA - PA) * = va(pagetable) - VA + PA * = pa(pagetable) */ ldr r1, [r0, #4] sub r0, r1, r2 mov pc, lr /* * Init MMU * r0 - the table base address */ ASENTRY_NP(init_mmu) /* Setup TLB and MMU registers */ mcr CP15_TTBR0(r0) /* Set TTB */ mov r0, #0 mcr CP15_CONTEXTIDR(r0) /* Set ASID to 0 */ /* Set the Domain Access register */ mov r0, #DOMAIN_CLIENT /* Only domain #0 is used */ mcr CP15_DACR(r0) /* * Set TEX remap registers * - All is set to uncacheable memory */ ldr r0, =0xAAAAA mcr CP15_PRRR(r0) mov r0, #0 mcr CP15_NMRR(r0) mcr CP15_TLBIALL /* Flush TLB */ DSB ISB /* Enable MMU */ mrc CP15_SCTLR(r0) orr r0, r0, #CPU_CONTROL_MMU_ENABLE orr r0, r0, #CPU_CONTROL_V6_EXTPAGE orr r0, r0, #CPU_CONTROL_TR_ENABLE orr r0, r0, #CPU_CONTROL_AF_ENABLE mcr CP15_SCTLR(r0) DSB ISB mcr CP15_TLBIALL /* Flush TLB */ mcr CP15_BPIALL /* Flush Branch predictor */ DSB ISB mov pc, lr END(init_mmu) /* * Init SMP coherent mode, enable caching and switch to final MMU table. * Called with disabled caches * r0 - The table base address * r1 - clear bits for aux register * r2 - set bits for aux register */ ASENTRY_NP(reinit_mmu) push {r4-r11, lr} mov r4, r0 mov r5, r1 mov r6, r2 /* !! Be very paranoid here !! */ /* !! We cannot write single bit here !! */ #if 0 /* XXX writeback shouldn't be necessary */ /* Write back and invalidate all integrated caches */ bl dcache_wbinv_poc_all #else bl dcache_inv_pou_all #endif mcr CP15_ICIALLU DSB ISB /* Set auxiliary register */ mrc CP15_ACTLR(r7) bic r8, r7, r5 /* Mask bits */ eor r8, r8, r6 /* Set bits */ teq r7, r8 mcrne CP15_ACTLR(r8) DSB ISB /* Enable caches. */ mrc CP15_SCTLR(r7) orr r7, #CPU_CONTROL_DC_ENABLE orr r7, #CPU_CONTROL_IC_ENABLE orr r7, #CPU_CONTROL_BPRD_ENABLE mcr CP15_SCTLR(r7) DSB mcr CP15_TTBR0(r4) /* Set new TTB */ DSB ISB mcr CP15_TLBIALL /* Flush TLB */ mcr CP15_BPIALL /* Flush Branch predictor */ DSB ISB #if 0 /* XXX writeback shouldn't be necessary */ /* Write back and invalidate all integrated caches */ bl dcache_wbinv_poc_all #else bl dcache_inv_pou_all #endif mcr CP15_ICIALLU DSB ISB pop {r4-r11, pc} END(reinit_mmu) /* * Builds the page table * r0 - The table base address * r1 - The physical address (trashed) * r2 - The virtual address (trashed) * r3 - The number of 1MiB sections * r4 - Trashed * * Addresses must be 1MiB aligned */ build_device_pagetables: ldr r4, =PTE1_V|PTE1_A|PTE1_AP_KRW|TEX1_CLASS_0 b 1f build_pagetables: /* Set the required page attributed */ ldr r4, =PTE1_V|PTE1_A|PTE1_AP_KRW|TEX1_CLASS_0 1: orr r1, r4 /* Move the virtual address to the correct bit location */ lsr r2, #(PTE1_SHIFT - 2) mov r4, r3 2: str r1, [r0, r2] add r2, r2, #4 add r1, r1, #(PTE1_SIZE) adds r4, r4, #-1 bhi 2b mov pc, lr VA_TO_PA_POINTER(Lpagetable, boot_pt1) .global _C_LABEL(hypmode_enabled) _C_LABEL(hypmode_enabled): .word 0 .Lstart: .word _edata /* Note that these three items are */ .word _ebss /* loaded with a single ldmia and */ .word svcstk /* must remain in order together. */ .Lmainreturned: .asciz "main() returned" .align 2 .bss svcstk: .space INIT_ARM_STACK_SIZE * MAXCPU /* * Memory for the initial pagetable. We are unable to place this in * the bss as this will be cleared after the table is loaded. */ .section ".init_pagetable" .align 14 /* 16KiB aligned */ .globl boot_pt1 boot_pt1: .space L1_TABLE_SIZE .text .align 2 .Lcpufuncs: .word _C_LABEL(cpufuncs) #if defined(SMP) ASENTRY_NP(mpentry) # If HYP-MODE is active, install an exception vector stub bl hypervisor_stub_vect_install adr r1, hypmode_enabled str r0, [r1] mov r0, 0 mov r1, 0 /* Setup status register for supervisor mode, interrupts disabled */ msr cpsr_fc, #0xd3 LEAVE_HYP /* Setup core, disable all caches. */ mrc CP15_SCTLR(r0) bic r0, #CPU_CONTROL_MMU_ENABLE bic r0, #CPU_CONTROL_AFLT_ENABLE bic r0, #CPU_CONTROL_DC_ENABLE bic r0, #CPU_CONTROL_IC_ENABLE bic r0, #CPU_CONTROL_BPRD_ENABLE bic r0, #CPU_CONTROL_SW_ENABLE orr r0, #CPU_CONTROL_UNAL_ENABLE orr r0, #CPU_CONTROL_VECRELOC mcr CP15_SCTLR(r0) DSB ISB /* Invalidate L1 cache I+D cache */ bl dcache_inv_pou_all mcr CP15_ICIALLU DSB ISB /* Find the delta between VA and PA */ adr r0, Lpagetable bl translate_va_to_pa bl init_mmu adr r1, .Lstart+8 /* Get initstack pointer from */ ldr sp, [r1] /* startup data. */ mrc CP15_MPIDR(r0) /* Get processor id number. */ and r0, r0, #0x0f mov r1, #INIT_ARM_STACK_SIZE mul r2, r1, r0 /* Point sp to initstack */ add sp, sp, r2 /* area for this processor. */ /* Switch to virtual addresses. */ ldr pc, =1f 1: mov fp, #0 /* trace back starts here */ bl _C_LABEL(init_secondary)/* Off we go, cpu id in r0. */ adr r0, .Lmpreturned b _C_LABEL(panic) /* NOTREACHED */ END(mpentry) .Lmpreturned: .asciz "init_secondary() returned" .align 2 #endif ENTRY_NP(cpu_halt) /* XXX re-implement !!! */ cpsid ifa bl dcache_wbinv_poc_all ldr r4, .Lcpu_reset_address ldr r4, [r4] teq r4, #0 movne pc, r4 1: WFI b 1b /* * _cpu_reset_address contains the address to branch to, to complete * the cpu reset after turning the MMU off * This variable is provided by the hardware specific code */ .Lcpu_reset_address: .word _C_LABEL(cpu_reset_address) END(cpu_halt) /* * setjump + longjmp */ ENTRY(setjmp) stmia r0, {r4-r14} mov r0, #0x00000000 RET END(setjmp) ENTRY(longjmp) ldmia r0, {r4-r14} mov r0, #0x00000001 RET END(longjmp) .data .global _C_LABEL(esym) _C_LABEL(esym): .word _C_LABEL(end) ENTRY_NP(abort) b _C_LABEL(abort) END(abort) ENTRY_NP(sigcode) mov r0, sp add r0, r0, #SIGF_UC /* * Call the sigreturn system call. * * We have to load r7 manually rather than using * "ldr r7, =SYS_sigreturn" to ensure the value of szsigcode is * correct. Using the alternative places esigcode at the address * of the data rather than the address one past the data. */ ldr r7, [pc, #12] /* Load SYS_sigreturn */ swi SYS_sigreturn /* Well if that failed we better exit quick ! */ ldr r7, [pc, #8] /* Load SYS_exit */ swi SYS_exit /* Branch back to retry SYS_sigreturn */ b . - 16 END(sigcode) .word SYS_sigreturn .word SYS_exit .align 2 .global _C_LABEL(esigcode) _C_LABEL(esigcode): .data .global szsigcode szsigcode: .long esigcode-sigcode /* End of locore.S */