/* * linux/arch/arm/mm/proc-v6.S * * Copyright (C) 2001 Deep Blue Solutions Ltd. * Modified by Catalin Marinas for noMMU support * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * This is the "shell" of the ARMv6 processor support. */ #include <linux/linkage.h> #include <asm/assembler.h> #include <asm/asm-offsets.h> #include <asm/elf.h> #include <asm/pgtable-hwdef.h> #include <asm/pgtable.h> #ifdef CONFIG_SMP #include <asm/hardware/arm_scu.h> #endif #include "proc-macros.S" #define D_CACHE_LINE_SIZE 32 #define TTB_C (1 << 0) #define TTB_S (1 << 1) #define TTB_IMP (1 << 2) #define TTB_RGN_NC (0 << 3) #define TTB_RGN_WBWA (1 << 3) #define TTB_RGN_WT (2 << 3) #define TTB_RGN_WB (3 << 3) #ifndef CONFIG_SMP #define TTB_FLAGS TTB_RGN_WBWA #else #define TTB_FLAGS TTB_RGN_WBWA|TTB_S #endif ENTRY(cpu_v6_proc_init) mov pc, lr ENTRY(cpu_v6_proc_fin) stmfd sp!, {lr} cpsid if @ disable interrupts bl v6_flush_kern_cache_all mrc p15, 0, r0, c1, c0, 0 @ ctrl register bic r0, r0, #0x1000 @ ...i............ bic r0, r0, #0x0006 @ .............ca. mcr p15, 0, r0, c1, c0, 0 @ disable caches ldmfd sp!, {pc} /* * cpu_v6_reset(loc) * * Perform a soft reset of the system. Put the CPU into the * same state as it would be if it had been reset, and branch * to what would be the reset vector. * * - loc - location to jump to for soft reset * * It is assumed that: */ .align 5 ENTRY(cpu_v6_reset) mov pc, r0 /* * cpu_v6_do_idle() * * Idle the processor (eg, wait for interrupt). * * IRQs are already disabled. */ ENTRY(cpu_v6_do_idle) mcr p15, 0, r1, c7, c0, 4 @ wait for interrupt mov pc, lr ENTRY(cpu_v6_dcache_clean_area) #ifndef TLB_CAN_READ_FROM_L1_CACHE 1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry add r0, r0, #D_CACHE_LINE_SIZE subs r1, r1, #D_CACHE_LINE_SIZE bhi 1b #endif mov pc, lr /* * cpu_arm926_switch_mm(pgd_phys, tsk) * * Set the translation table base pointer to be pgd_phys * * - pgd_phys - physical address of new TTB * * It is assumed that: * - we are not using split page tables */ ENTRY(cpu_v6_switch_mm) #ifdef CONFIG_MMU mov r2, #0 ldr r1, [r1, #MM_CONTEXT_ID] @ get mm->context.id orr r0, r0, #TTB_FLAGS mcr p15, 0, r2, c7, c5, 6 @ flush BTAC/BTB mcr p15, 0, r2, c7, c10, 4 @ drain write buffer mcr p15, 0, r0, c2, c0, 0 @ set TTB 0 mcr p15, 0, r1, c13, c0, 1 @ set context ID #endif mov pc, lr /* * cpu_v6_set_pte_ext(ptep, pte, ext) * * Set a level 2 translation table entry. * * - ptep - pointer to level 2 translation table entry * (hardware version is stored at -1024 bytes) * - pte - PTE value to store * - ext - value for extended PTE bits * * Permissions: * YUWD APX AP1 AP0 SVC User * 0xxx 0 0 0 no acc no acc * 100x 1 0 1 r/o no acc * 10x0 1 0 1 r/o no acc * 1011 0 0 1 r/w no acc * 110x 0 1 0 r/w r/o * 11x0 0 1 0 r/w r/o * 1111 0 1 1 r/w r/w */ ENTRY(cpu_v6_set_pte_ext) #ifdef CONFIG_MMU str r1, [r0], #-2048 @ linux version bic r3, r1, #0x000003f0 bic r3, r3, #0x00000003 orr r3, r3, r2 orr r3, r3, #PTE_EXT_AP0 | 2 tst r1, #L_PTE_WRITE tstne r1, #L_PTE_DIRTY orreq r3, r3, #PTE_EXT_APX tst r1, #L_PTE_USER orrne r3, r3, #PTE_EXT_AP1 tstne r3, #PTE_EXT_APX bicne r3, r3, #PTE_EXT_APX | PTE_EXT_AP0 tst r1, #L_PTE_YOUNG biceq r3, r3, #PTE_EXT_APX | PTE_EXT_AP_MASK tst r1, #L_PTE_EXEC orreq r3, r3, #PTE_EXT_XN tst r1, #L_PTE_PRESENT moveq r3, #0 str r3, [r0] mcr p15, 0, r0, c7, c10, 1 @ flush_pte #endif mov pc, lr cpu_v6_name: .asciz "ARMv6-compatible processor" .align .section ".text.init", #alloc, #execinstr /* * __v6_setup * * Initialise TLB, Caches, and MMU state ready to switch the MMU * on. Return in r0 the new CP15 C1 control register setting. * * We automatically detect if we have a Harvard cache, and use the * Harvard cache control instructions insead of the unified cache * control instructions. * * This should be able to cover all ARMv6 cores. * * It is assumed that: * - cache type register is implemented */ __v6_setup: #ifdef CONFIG_SMP /* Set up the SCU on core 0 only */ mrc p15, 0, r0, c0, c0, 5 @ CPU core number ands r0, r0, #15 ldreq r0, =SCU_BASE ldreq r5, [r0, #SCU_CTRL] orreq r5, r5, #1 streq r5, [r0, #SCU_CTRL] #ifndef CONFIG_CPU_DCACHE_DISABLE mrc p15, 0, r0, c1, c0, 1 @ Enable SMP/nAMP mode orr r0, r0, #0x20 mcr p15, 0, r0, c1, c0, 1 #endif #endif mov r0, #0 mcr p15, 0, r0, c7, c14, 0 @ clean+invalidate D cache mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache mcr p15, 0, r0, c7, c15, 0 @ clean+invalidate cache mcr p15, 0, r0, c7, c10, 4 @ drain write buffer #ifdef CONFIG_MMU mcr p15, 0, r0, c8, c7, 0 @ invalidate I + D TLBs mcr p15, 0, r0, c2, c0, 2 @ TTB control register orr r4, r4, #TTB_FLAGS mcr p15, 0, r4, c2, c0, 1 @ load TTB1 #endif /* CONFIG_MMU */ adr r5, v6_crval ldmia r5, {r5, r6} mrc p15, 0, r0, c1, c0, 0 @ read control register bic r0, r0, r5 @ clear bits them orr r0, r0, r6 @ set them mov pc, lr @ return to head.S:__ret /* * V X F I D LR * .... ...E PUI. .T.T 4RVI ZFRS BLDP WCAM * rrrr rrrx xxx0 0101 xxxx xxxx x111 xxxx < forced * 0 110 0011 1.00 .111 1101 < we want */ .type v6_crval, #object v6_crval: crval clear=0x01e0fb7f, mmuset=0x00c0387d, ucset=0x00c0187c .type v6_processor_functions, #object ENTRY(v6_processor_functions) .word v6_early_abort .word cpu_v6_proc_init .word cpu_v6_proc_fin .word cpu_v6_reset .word cpu_v6_do_idle .word cpu_v6_dcache_clean_area .word cpu_v6_switch_mm .word cpu_v6_set_pte_ext .size v6_processor_functions, . - v6_processor_functions .type cpu_arch_name, #object cpu_arch_name: .asciz "armv6" .size cpu_arch_name, . - cpu_arch_name .type cpu_elf_name, #object cpu_elf_name: .asciz "v6" .size cpu_elf_name, . - cpu_elf_name .align .section ".proc.info.init", #alloc, #execinstr /* * Match any ARMv6 processor core. */ .type __v6_proc_info, #object __v6_proc_info: .long 0x0007b000 .long 0x0007f000 .long PMD_TYPE_SECT | \ PMD_SECT_BUFFERABLE | \ PMD_SECT_CACHEABLE | \ PMD_SECT_AP_WRITE | \ PMD_SECT_AP_READ .long PMD_TYPE_SECT | \ PMD_SECT_XN | \ PMD_SECT_AP_WRITE | \ PMD_SECT_AP_READ b __v6_setup .long cpu_arch_name .long cpu_elf_name .long HWCAP_SWP|HWCAP_HALF|HWCAP_THUMB|HWCAP_FAST_MULT|HWCAP_EDSP|HWCAP_JAVA .long cpu_v6_name .long v6_processor_functions .long v6wbi_tlb_fns .long v6_user_fns .long v6_cache_fns .size __v6_proc_info, . - __v6_proc_info