/* SPDX-License-Identifier: GPL-2.0 */
/* GENpage.S: Generic clear and copy page.
 *
 * Copyright (C) 2007 (davem@davemloft.net)
 */
#include <asm/page.h>

        .text
        .align  32

GENcopy_user_page:
        set     PAGE_SIZE, %g7
1:      ldx     [%o1 + 0x00], %o2
        ldx     [%o1 + 0x08], %o3
        ldx     [%o1 + 0x10], %o4
        ldx     [%o1 + 0x18], %o5
        stx     %o2, [%o0 + 0x00]
        stx     %o3, [%o0 + 0x08]
        stx     %o4, [%o0 + 0x10]
        stx     %o5, [%o0 + 0x18]
        ldx     [%o1 + 0x20], %o2
        ldx     [%o1 + 0x28], %o3
        ldx     [%o1 + 0x30], %o4
        ldx     [%o1 + 0x38], %o5
        stx     %o2, [%o0 + 0x20]
        stx     %o3, [%o0 + 0x28]
        stx     %o4, [%o0 + 0x30]
        stx     %o5, [%o0 + 0x38]
        subcc   %g7, 64, %g7
        add     %o1, 64, %o1
        bne,pt  %xcc, 1b
         add    %o0, 64, %o0
        retl
         nop

GENclear_page:
GENclear_user_page:
        set     PAGE_SIZE, %g7
1:      stx     %g0, [%o0 + 0x00]
        stx     %g0, [%o0 + 0x08]
        stx     %g0, [%o0 + 0x10]
        stx     %g0, [%o0 + 0x18]
        stx     %g0, [%o0 + 0x20]
        stx     %g0, [%o0 + 0x28]
        stx     %g0, [%o0 + 0x30]
        stx     %g0, [%o0 + 0x38]
        subcc   %g7, 64, %g7
        bne,pt  %xcc, 1b
         add    %o0, 64, %o0

#define BRANCH_ALWAYS   0x10680000
#define NOP             0x01000000
#define GEN_DO_PATCH(OLD, NEW)  \
        sethi   %hi(NEW), %g1; \
        or      %g1, %lo(NEW), %g1; \
        sethi   %hi(OLD), %g2; \
        or      %g2, %lo(OLD), %g2; \
        sub     %g1, %g2, %g1; \
        sethi   %hi(BRANCH_ALWAYS), %g3; \
        sll     %g1, 11, %g1; \
        srl     %g1, 11 + 2, %g1; \
        or      %g3, %lo(BRANCH_ALWAYS), %g3; \
        or      %g3, %g1, %g3; \
        stw     %g3, [%g2]; \
        sethi   %hi(NOP), %g3; \
        or      %g3, %lo(NOP), %g3; \
        stw     %g3, [%g2 + 0x4]; \
        flush   %g2;

        .globl  generic_patch_pageops
        .type   generic_patch_pageops,#function
generic_patch_pageops:
        GEN_DO_PATCH(copy_user_page, GENcopy_user_page)
        GEN_DO_PATCH(_clear_page, GENclear_page)
        GEN_DO_PATCH(clear_user_page, GENclear_user_page)
        retl
         nop
        .size   generic_patch_pageops,.-generic_patch_pageops