/* * arch/xtensa/include/asm/initialize_mmu.h * * Initializes MMU: * * For the new V3 MMU we remap the TLB from virtual == physical * to the standard Linux mapping used in earlier MMU's. * * The the MMU we also support a new configuration register that * specifies how the S32C1I instruction operates with the cache * controller. * * This file is subject to the terms and conditions of the GNU General * Public License. See the file "COPYING" in the main directory of * this archive for more details. * * Copyright (C) 2008 - 2012 Tensilica, Inc. * * Marc Gauthier <marc@tensilica.com> * Pete Delaney <piet@tensilica.com> */ #ifndef _XTENSA_INITIALIZE_MMU_H #define _XTENSA_INITIALIZE_MMU_H #include <asm/pgtable.h> #include <asm/vectors.h> #if XCHAL_HAVE_PTP_MMU #define CA_BYPASS (_PAGE_CA_BYPASS | _PAGE_HW_WRITE | _PAGE_HW_EXEC) #define CA_WRITEBACK (_PAGE_CA_WB | _PAGE_HW_WRITE | _PAGE_HW_EXEC) #else #define CA_WRITEBACK (0x4) #endif #ifndef XCHAL_SPANNING_WAY #define XCHAL_SPANNING_WAY 0 #endif #ifdef __ASSEMBLY__ #define XTENSA_HWVERSION_RC_2009_0 230000 .macro initialize_mmu #if XCHAL_HAVE_S32C1I && (XCHAL_HW_MIN_VERSION >= XTENSA_HWVERSION_RC_2009_0) /* * We Have Atomic Operation Control (ATOMCTL) Register; Initialize it. * For details see Documentation/xtensa/atomctl.txt */ #if XCHAL_DCACHE_IS_COHERENT movi a3, 0x25 /* For SMP/MX -- internal for writeback, * RCW otherwise */ #else movi a3, 0x29 /* non-MX -- Most cores use Std Memory * Controlers which usually can't use RCW */ #endif wsr a3, atomctl #endif /* XCHAL_HAVE_S32C1I && * (XCHAL_HW_MIN_VERSION >= XTENSA_HWVERSION_RC_2009_0) */ #if defined(CONFIG_MMU) && XCHAL_HAVE_PTP_MMU && XCHAL_HAVE_SPANNING_WAY /* * Have MMU v3 */ #if !XCHAL_HAVE_VECBASE # error "MMU v3 requires reloc vectors" #endif movi a1, 0 _call0 1f _j 2f .align 4 1: movi a2, 0x10000000 movi a3, 0x18000000 add a2, a2, a0 9: bgeu a2, a3, 9b /* PC is out of the expected range */ /* Step 1: invalidate mapping at 0x40000000..0x5FFFFFFF. */ movi a2, 0x40000000 | XCHAL_SPANNING_WAY idtlb a2 iitlb a2 isync /* Step 2: map 0x40000000..0x47FFFFFF to paddr containing this code * and jump to the new mapping. */ srli a3, a0, 27 slli a3, a3, 27 addi a3, a3, CA_BYPASS addi a7, a2, -1 wdtlb a3, a7 witlb a3, a7 isync slli a4, a0, 5 srli a4, a4, 5 addi a5, a2, -6 add a4, a4, a5 jx a4 /* Step 3: unmap everything other than current area. * Start at 0x60000000, wrap around, and end with 0x20000000 */ 2: movi a4, 0x20000000 add a5, a2, a4 3: idtlb a5 iitlb a5 add a5, a5, a4 bne a5, a2, 3b /* Step 4: Setup MMU with the old V2 mappings. */ movi a6, 0x01000000 wsr a6, ITLBCFG wsr a6, DTLBCFG isync movi a5, 0xd0000005 movi a4, CA_WRITEBACK wdtlb a4, a5 witlb a4, a5 movi a5, 0xd8000005 movi a4, CA_BYPASS wdtlb a4, a5 witlb a4, a5 movi a5, XCHAL_KIO_CACHED_VADDR + 6 movi a4, XCHAL_KIO_DEFAULT_PADDR + CA_WRITEBACK wdtlb a4, a5 witlb a4, a5 movi a5, XCHAL_KIO_BYPASS_VADDR + 6 movi a4, XCHAL_KIO_DEFAULT_PADDR + CA_BYPASS wdtlb a4, a5 witlb a4, a5 isync /* Jump to self, using MMU v2 mappings. */ movi a4, 1f jx a4 1: /* Step 5: remove temporary mapping. */ idtlb a7 iitlb a7 isync movi a0, 0 wsr a0, ptevaddr rsync #endif /* defined(CONFIG_MMU) && XCHAL_HAVE_PTP_MMU && XCHAL_HAVE_SPANNING_WAY */ #if !defined(CONFIG_MMU) && XCHAL_HAVE_TLBS /* Enable data and instruction cache in the DEFAULT_MEMORY region * if the processor has DTLB and ITLB. */ movi a5, PLATFORM_DEFAULT_MEM_START | XCHAL_SPANNING_WAY movi a6, ~_PAGE_ATTRIB_MASK movi a7, CA_WRITEBACK movi a8, 0x20000000 movi a9, PLATFORM_DEFAULT_MEM_SIZE j 2f 1: sub a9, a9, a8 2: rdtlb1 a3, a5 ritlb1 a4, a5 and a3, a3, a6 and a4, a4, a6 or a3, a3, a7 or a4, a4, a7 wdtlb a3, a5 witlb a4, a5 add a5, a5, a8 bltu a8, a9, 1b #endif .endm #endif /*__ASSEMBLY__*/ #endif /* _XTENSA_INITIALIZE_MMU_H */