/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * This file contains the generic code to perform a call to the
 * pSeries LPAR hypervisor.
 */
#include <linux/jump_label.h>
#include <asm/hvcall.h>
#include <asm/processor.h>
#include <asm/ppc_asm.h>
#include <asm/asm-offsets.h>
#include <asm/ptrace.h>
#include <asm/feature-fixups.h>

        .section        ".text"
        
#ifdef CONFIG_TRACEPOINTS

#ifndef CONFIG_JUMP_LABEL
        .data

        .globl hcall_tracepoint_refcount
hcall_tracepoint_refcount:
        .8byte  0

        .section        ".text"
#endif

/*
 * precall must preserve all registers.  use unused STK_PARAM()
 * areas to save snapshots and opcode. STK_PARAM() in the caller's
 * frame will be available even on ELFv2 because these are all
 * variadic functions.
 */
#define HCALL_INST_PRECALL(FIRST_REG)                           \
        mflr    r0;                                             \
        std     r3,STK_PARAM(R3)(r1);                           \
        std     r4,STK_PARAM(R4)(r1);                           \
        std     r5,STK_PARAM(R5)(r1);                           \
        std     r6,STK_PARAM(R6)(r1);                           \
        std     r7,STK_PARAM(R7)(r1);                           \
        std     r8,STK_PARAM(R8)(r1);                           \
        std     r9,STK_PARAM(R9)(r1);                           \
        std     r10,STK_PARAM(R10)(r1);                         \
        std     r0,16(r1);                                      \
        addi    r4,r1,STK_PARAM(FIRST_REG);                     \
        stdu    r1,-STACK_FRAME_MIN_SIZE(r1);                   \
        bl      CFUNC(__trace_hcall_entry);                     \
        ld      r3,STACK_FRAME_MIN_SIZE+STK_PARAM(R3)(r1);      \
        ld      r4,STACK_FRAME_MIN_SIZE+STK_PARAM(R4)(r1);      \
        ld      r5,STACK_FRAME_MIN_SIZE+STK_PARAM(R5)(r1);      \
        ld      r6,STACK_FRAME_MIN_SIZE+STK_PARAM(R6)(r1);      \
        ld      r7,STACK_FRAME_MIN_SIZE+STK_PARAM(R7)(r1);      \
        ld      r8,STACK_FRAME_MIN_SIZE+STK_PARAM(R8)(r1);      \
        ld      r9,STACK_FRAME_MIN_SIZE+STK_PARAM(R9)(r1);      \
        ld      r10,STACK_FRAME_MIN_SIZE+STK_PARAM(R10)(r1)

/*
 * postcall is performed immediately before function return which
 * allows liberal use of volatile registers.
 */
#define __HCALL_INST_POSTCALL                                   \
        ld      r0,STACK_FRAME_MIN_SIZE+STK_PARAM(R3)(r1);      \
        std     r3,STACK_FRAME_MIN_SIZE+STK_PARAM(R3)(r1);      \
        mr      r4,r3;                                          \
        mr      r3,r0;                                          \
        bl      CFUNC(__trace_hcall_exit);                      \
        ld      r0,STACK_FRAME_MIN_SIZE+16(r1);                 \
        addi    r1,r1,STACK_FRAME_MIN_SIZE;                     \
        ld      r3,STK_PARAM(R3)(r1);                           \
        mtlr    r0

#define HCALL_INST_POSTCALL_NORETS                              \
        li      r5,0;                                           \
        __HCALL_INST_POSTCALL

#define HCALL_INST_POSTCALL(BUFREG)                             \
        mr      r5,BUFREG;                                      \
        __HCALL_INST_POSTCALL

#ifdef CONFIG_JUMP_LABEL
#define HCALL_BRANCH(LABEL)                                     \
        ARCH_STATIC_BRANCH(LABEL, hcall_tracepoint_key)
#else

/*
 * We branch around this in early init (eg when populating the MMU
 * hashtable) by using an unconditional cpu feature.
 */
#define HCALL_BRANCH(LABEL)                                     \
BEGIN_FTR_SECTION;                                              \
        b       1f;                                             \
END_FTR_SECTION(0, 1);                                          \
        LOAD_REG_ADDR(r12, hcall_tracepoint_refcount) ;         \
        ld      r12,0(r12);                                     \
        cmpdi   r12,0;                                          \
        bne-    LABEL;                                          \
1:
#endif

#else
#define HCALL_INST_PRECALL(FIRST_ARG)
#define HCALL_INST_POSTCALL_NORETS
#define HCALL_INST_POSTCALL(BUFREG)
#define HCALL_BRANCH(LABEL)
#endif

_GLOBAL_TOC(plpar_hcall_norets_notrace)
        HMT_MEDIUM

        mfcr    r0
        stw     r0,8(r1)
        HVSC                            /* invoke the hypervisor */

        li      r4,0
        stb     r4,PACASRR_VALID(r13)

        lwz     r0,8(r1)
        mtcrf   0xff,r0
        blr                             /* return r3 = status */

_GLOBAL_TOC(plpar_hcall_norets)
        HMT_MEDIUM

        mfcr    r0
        stw     r0,8(r1)
        HCALL_BRANCH(plpar_hcall_norets_trace)
        HVSC                            /* invoke the hypervisor */

        li      r4,0
        stb     r4,PACASRR_VALID(r13)

        lwz     r0,8(r1)
        mtcrf   0xff,r0
        blr                             /* return r3 = status */

#ifdef CONFIG_TRACEPOINTS
plpar_hcall_norets_trace:
        HCALL_INST_PRECALL(R4)
        HVSC
        HCALL_INST_POSTCALL_NORETS

        li      r4,0
        stb     r4,PACASRR_VALID(r13)

        lwz     r0,8(r1)
        mtcrf   0xff,r0
        blr
#endif

_GLOBAL_TOC(plpar_hcall)
        HMT_MEDIUM

        mfcr    r0
        stw     r0,8(r1)

        HCALL_BRANCH(plpar_hcall_trace)

        std     r4,STK_PARAM(R4)(r1)     /* Save ret buffer */

        mr      r4,r5
        mr      r5,r6
        mr      r6,r7
        mr      r7,r8
        mr      r8,r9
        mr      r9,r10

        HVSC                            /* invoke the hypervisor */

        ld      r12,STK_PARAM(R4)(r1)
        std     r4,  0(r12)
        std     r5,  8(r12)
        std     r6, 16(r12)
        std     r7, 24(r12)

        li      r4,0
        stb     r4,PACASRR_VALID(r13)

        lwz     r0,8(r1)
        mtcrf   0xff,r0

        blr                             /* return r3 = status */

#ifdef CONFIG_TRACEPOINTS
plpar_hcall_trace:
        HCALL_INST_PRECALL(R5)

        mr      r4,r5
        mr      r5,r6
        mr      r6,r7
        mr      r7,r8
        mr      r8,r9
        mr      r9,r10

        HVSC

        ld      r12,STACK_FRAME_MIN_SIZE+STK_PARAM(R4)(r1)
        std     r4,0(r12)
        std     r5,8(r12)
        std     r6,16(r12)
        std     r7,24(r12)

        HCALL_INST_POSTCALL(r12)

        li      r4,0
        stb     r4,PACASRR_VALID(r13)

        lwz     r0,8(r1)
        mtcrf   0xff,r0

        blr
#endif

/*
 * plpar_hcall_raw can be called in real mode. kexec/kdump need some
 * hypervisor calls to be executed in real mode. So plpar_hcall_raw
 * does not access the per cpu hypervisor call statistics variables,
 * since these variables may not be present in the RMO region.
 */
_GLOBAL(plpar_hcall_raw)
        HMT_MEDIUM

        mfcr    r0
        stw     r0,8(r1)

        std     r4,STK_PARAM(R4)(r1)     /* Save ret buffer */

        mr      r4,r5
        mr      r5,r6
        mr      r6,r7
        mr      r7,r8
        mr      r8,r9
        mr      r9,r10

        HVSC                            /* invoke the hypervisor */

        ld      r12,STK_PARAM(R4)(r1)
        std     r4,  0(r12)
        std     r5,  8(r12)
        std     r6, 16(r12)
        std     r7, 24(r12)

        li      r4,0
        stb     r4,PACASRR_VALID(r13)

        lwz     r0,8(r1)
        mtcrf   0xff,r0

        blr                             /* return r3 = status */

_GLOBAL_TOC(plpar_hcall9)
        HMT_MEDIUM

        mfcr    r0
        stw     r0,8(r1)

        HCALL_BRANCH(plpar_hcall9_trace)

        std     r4,STK_PARAM(R4)(r1)     /* Save ret buffer */

        mr      r4,r5
        mr      r5,r6
        mr      r6,r7
        mr      r7,r8
        mr      r8,r9
        mr      r9,r10
        ld      r10,STK_PARAM(R11)(r1)   /* put arg7 in R10 */
        ld      r11,STK_PARAM(R12)(r1)   /* put arg8 in R11 */
        ld      r12,STK_PARAM(R13)(r1)    /* put arg9 in R12 */

        HVSC                            /* invoke the hypervisor */

        mr      r0,r12
        ld      r12,STK_PARAM(R4)(r1)
        std     r4,  0(r12)
        std     r5,  8(r12)
        std     r6, 16(r12)
        std     r7, 24(r12)
        std     r8, 32(r12)
        std     r9, 40(r12)
        std     r10,48(r12)
        std     r11,56(r12)
        std     r0, 64(r12)

        li      r4,0
        stb     r4,PACASRR_VALID(r13)

        lwz     r0,8(r1)
        mtcrf   0xff,r0

        blr                             /* return r3 = status */

#ifdef CONFIG_TRACEPOINTS
plpar_hcall9_trace:
        HCALL_INST_PRECALL(R5)

        mr      r4,r5
        mr      r5,r6
        mr      r6,r7
        mr      r7,r8
        mr      r8,r9
        mr      r9,r10
        ld      r10,STACK_FRAME_MIN_SIZE+STK_PARAM(R11)(r1)
        ld      r11,STACK_FRAME_MIN_SIZE+STK_PARAM(R12)(r1)
        ld      r12,STACK_FRAME_MIN_SIZE+STK_PARAM(R13)(r1)

        HVSC

        mr      r0,r12
        ld      r12,STACK_FRAME_MIN_SIZE+STK_PARAM(R4)(r1)
        std     r4,0(r12)
        std     r5,8(r12)
        std     r6,16(r12)
        std     r7,24(r12)
        std     r8,32(r12)
        std     r9,40(r12)
        std     r10,48(r12)
        std     r11,56(r12)
        std     r0,64(r12)

        HCALL_INST_POSTCALL(r12)

        li      r4,0
        stb     r4,PACASRR_VALID(r13)

        lwz     r0,8(r1)
        mtcrf   0xff,r0

        blr
#endif

/* See plpar_hcall_raw to see why this is needed */
_GLOBAL(plpar_hcall9_raw)
        HMT_MEDIUM

        mfcr    r0
        stw     r0,8(r1)

        std     r4,STK_PARAM(R4)(r1)     /* Save ret buffer */

        mr      r4,r5
        mr      r5,r6
        mr      r6,r7
        mr      r7,r8
        mr      r8,r9
        mr      r9,r10
        ld      r10,STK_PARAM(R11)(r1)   /* put arg7 in R10 */
        ld      r11,STK_PARAM(R12)(r1)   /* put arg8 in R11 */
        ld      r12,STK_PARAM(R13)(r1)    /* put arg9 in R12 */

        HVSC                            /* invoke the hypervisor */

        mr      r0,r12
        ld      r12,STK_PARAM(R4)(r1)
        std     r4,  0(r12)
        std     r5,  8(r12)
        std     r6, 16(r12)
        std     r7, 24(r12)
        std     r8, 32(r12)
        std     r9, 40(r12)
        std     r10,48(r12)
        std     r11,56(r12)
        std     r0, 64(r12)

        li      r4,0
        stb     r4,PACASRR_VALID(r13)

        lwz     r0,8(r1)
        mtcrf   0xff,r0

        blr                             /* return r3 = status */