/*
 * 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.
 *
 *      For 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 <linux/init.h>
#include <linux/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

#ifdef __ASSEMBLER__

#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/arch/xtensa/atomctl.rst
 */
#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:

#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 || XCHAL_HAVE_MPU)
#if CONFIG_MEMMAP_CACHEATTR == 0x22222222 && XCHAL_HAVE_PTP_MMU
#error Default MEMMAP_CACHEATTR of 0x22222222 does not work with full MMU.
#endif

#if XCHAL_HAVE_MPU
        __REFCONST
        .align  4
.Lattribute_table:
        .long 0x000000, 0x1fff00, 0x1ddf00, 0x1eef00
        .long 0x006600, 0x000000, 0x000000, 0x000000
        .long 0x000000, 0x000000, 0x000000, 0x000000
        .long 0x000000, 0x000000, 0x000000, 0x000000
        .previous

        movi    a3, .Lattribute_table
        movi    a4, CONFIG_MEMMAP_CACHEATTR
        movi    a5, 1
        movi    a6, XCHAL_MPU_ENTRIES
        movi    a10, 0x20000000
        movi    a11, -1
1:
        sub     a5, a5, a10
        extui   a8, a4, 28, 4
        beq     a8, a11, 2f
        addi    a6, a6, -1
        mov     a11, a8
2:
        addx4   a9, a8, a3
        l32i    a9, a9, 0
        or      a9, a9, a6
        wptlb   a9, a5
        slli    a4, a4, 4
        bgeu    a5, a10, 1b

#else
        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
#endif

        .endm

#endif /*__ASSEMBLER__*/

#endif /* _XTENSA_INITIALIZE_MMU_H */