original_kernel/arch/xtensa/include/asm/initialize_mmu.h

217 lines
4.5 KiB
C

/*
* 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
#if CONFIG_KERNEL_LOAD_ADDRESS < 0x40000000ul
#define TEMP_MAPPING_VADDR 0x40000000
#else
#define TEMP_MAPPING_VADDR 0x00000000
#endif
/* Step 1: invalidate mapping at 0x40000000..0x5FFFFFFF. */
movi a2, TEMP_MAPPING_VADDR | 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, 5 - XCHAL_SPANNING_WAY
wdtlb a3, a7
witlb a3, a7
isync
slli a4, a0, 5
srli a4, a4, 5
addi a5, a2, -XCHAL_SPANNING_WAY
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 requested static mappings. */
movi a6, 0x01000000
wsr a6, ITLBCFG
wsr a6, DTLBCFG
isync
movi a5, XCHAL_KSEG_CACHED_VADDR + XCHAL_KSEG_TLB_WAY
movi a4, XCHAL_KSEG_PADDR + CA_WRITEBACK
wdtlb a4, a5
witlb a4, a5
movi a5, XCHAL_KSEG_BYPASS_VADDR + XCHAL_KSEG_TLB_WAY
movi a4, XCHAL_KSEG_PADDR + CA_BYPASS
wdtlb a4, a5
witlb a4, a5
#ifdef CONFIG_XTENSA_KSEG_512M
movi a5, XCHAL_KSEG_CACHED_VADDR + 0x10000000 + XCHAL_KSEG_TLB_WAY
movi a4, XCHAL_KSEG_PADDR + 0x10000000 + CA_WRITEBACK
wdtlb a4, a5
witlb a4, a5
movi a5, XCHAL_KSEG_BYPASS_VADDR + 0x10000000 + XCHAL_KSEG_TLB_WAY
movi a4, XCHAL_KSEG_PADDR + 0x10000000 + CA_BYPASS
wdtlb a4, a5
witlb a4, a5
#endif
movi a5, XCHAL_KIO_CACHED_VADDR + XCHAL_KIO_TLB_WAY
movi a4, XCHAL_KIO_DEFAULT_PADDR + CA_WRITEBACK
wdtlb a4, a5
witlb a4, a5
movi a5, XCHAL_KIO_BYPASS_VADDR + XCHAL_KIO_TLB_WAY
movi a4, XCHAL_KIO_DEFAULT_PADDR + CA_BYPASS
wdtlb a4, a5
witlb a4, a5
isync
/* Jump to self, using final 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 */
.endm
.macro initialize_cacheattr
#if !defined(CONFIG_MMU) && XCHAL_HAVE_TLBS
#if CONFIG_MEMMAP_CACHEATTR == 0x22222222 && XCHAL_HAVE_PTP_MMU
#error Default MEMMAP_CACHEATTR of 0x22222222 does not work with full MMU.
#endif
movi a5, XCHAL_SPANNING_WAY
movi a6, ~_PAGE_ATTRIB_MASK
movi a4, CONFIG_MEMMAP_CACHEATTR
movi a8, 0x20000000
1:
rdtlb1 a3, a5
xor a3, a3, a4
and a3, a3, a6
xor a3, a3, a4
wdtlb a3, a5
ritlb1 a3, a5
xor a3, a3, a4
and a3, a3, a6
xor a3, a3, a4
witlb a3, a5
add a5, a5, a8
srli a4, a4, 4
bgeu a5, a8, 1b
isync
#endif
.endm
#endif /*__ASSEMBLY__*/
#endif /* _XTENSA_INITIALIZE_MMU_H */