diff options
Diffstat (limited to 'kernel/arch/xtensa/include/asm/initialize_mmu.h')
| -rw-r--r-- | kernel/arch/xtensa/include/asm/initialize_mmu.h | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/kernel/arch/xtensa/include/asm/initialize_mmu.h b/kernel/arch/xtensa/include/asm/initialize_mmu.h new file mode 100644 index 000000000..e256f2270 --- /dev/null +++ b/kernel/arch/xtensa/include/asm/initialize_mmu.h @@ -0,0 +1,195 @@ +/* + * 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 */ |