root/arch/powerpc/platforms/powernv/opal-wrappers.S

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2 /*
   3  * PowerNV OPAL API wrappers
   4  *
   5  * Copyright 2011 IBM Corp.
   6  */
   7 
   8 #include <linux/jump_label.h>
   9 #include <asm/ppc_asm.h>
  10 #include <asm/hvcall.h>
  11 #include <asm/asm-offsets.h>
  12 #include <asm/opal.h>
  13 #include <asm/asm-compat.h>
  14 #include <asm/feature-fixups.h>
  15 
  16         .section ".text"
  17 
  18 /*
  19  * r3-r10               - OPAL call arguments
  20  * STK_PARAM(R11)       - OPAL opcode
  21  * STK_PARAM(R12)       - MSR to restore
  22  */
  23 _GLOBAL_TOC(__opal_call)
  24         mflr    r0
  25         std     r0,PPC_LR_STKOFF(r1)
  26         ld      r12,STK_PARAM(R12)(r1)
  27         li      r0,MSR_IR|MSR_DR|MSR_LE
  28         andc    r12,r12,r0
  29         LOAD_REG_ADDR(r11, opal_return)
  30         mtlr    r11
  31         LOAD_REG_ADDR(r11, opal)
  32         ld      r2,0(r11)
  33         ld      r11,8(r11)
  34         mtspr   SPRN_HSRR0,r11
  35         mtspr   SPRN_HSRR1,r12
  36         /* set token to r0 */
  37         ld      r0,STK_PARAM(R11)(r1)
  38         hrfid
  39 opal_return:
  40         /*
  41          * Restore MSR on OPAL return. The MSR is set to big-endian.
  42          */
  43 #ifdef __BIG_ENDIAN__
  44         ld      r11,STK_PARAM(R12)(r1)
  45         mtmsrd  r11
  46 #else
  47         /* Endian can only be switched with rfi, must byte reverse MSR load */
  48         .short 0x4039    /* li r10,STK_PARAM(R12)               */
  49         .byte (STK_PARAM(R12) >> 8) & 0xff
  50         .byte STK_PARAM(R12) & 0xff
  51 
  52         .long 0x280c6a7d /* ldbrx r11,r10,r1                    */
  53         .long 0x05009f42 /* bcl 20,31,$+4                       */
  54         .long 0xa602487d /* mflr r10                            */
  55         .long 0x14004a39 /* addi r10,r10,20                     */
  56         .long 0xa64b5a7d /* mthsrr0 r10                         */
  57         .long 0xa64b7b7d /* mthsrr1 r11                         */
  58         .long 0x2402004c /* hrfid                               */
  59 #endif
  60         ld      r2,PACATOC(r13)
  61         ld      r0,PPC_LR_STKOFF(r1)
  62         mtlr    r0
  63         blr