Changed LongJump() to _LongJump()

[mirror_edk2.git] / MdePkg / Library / BaseLib / Ipf / SwitchStack.s

//++\r
// Copyright (c) 2006, Intel Corporation                                                         \r
// All rights reserved. This program and the accompanying materials                          \r
// are licensed and made available under the terms and conditions of the BSD License         \r
// which accompanies this distribution.  The full text of the license may be found at        \r
// http://opensource.org/licenses/bsd-license.php                                            \r
//                                                                                           \r
// THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,                     \r
// WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.             \r
// \r
// Module Name:\r
//\r
//  SwitchStack.s\r
//\r
// Abstract:\r
//\r
//  Contains an implementation of a stack switch for the Itanium-based architecture.\r
//\r
//\r
//\r
// Revision History:\r
//\r
//--\r
\r
  .file  "SwitchStack.s"\r
\r
#include  "asm.h"\r
#include  "ia_64gen.h"\r
\r
// Define hardware RSE Configuration Register\r
//\r
// RS Configuration (RSC) bit field positions\r
\r
#define RSC_MODE       0\r
#define RSC_PL         2\r
#define RSC_BE         4\r
// RSC bits 5-15 reserved\r
#define RSC_MBZ0       5\r
#define RSC_MBZ0_V     0x3ff\r
#define RSC_LOADRS     16\r
#define RSC_LOADRS_LEN 14\r
// RSC bits 30-63 reserved\r
#define RSC_MBZ1       30\r
#define RSC_MBZ1_V     0x3ffffffffULL\r
\r
// RSC modes\r
// Lazy\r
#define RSC_MODE_LY (0x0)\r
// Store intensive\r
#define RSC_MODE_SI (0x1)\r
// Load intensive\r
#define RSC_MODE_LI (0x2)\r
// Eager\r
#define RSC_MODE_EA (0x3)\r
\r
// RSC Endian bit values\r
#define RSC_BE_LITTLE 0\r
#define RSC_BE_BIG    1\r
\r
// RSC while in kernel: enabled, little endian, pl = 0, eager mode\r
#define RSC_KERNEL ((RSC_MODE_EA<<RSC_MODE) | (RSC_BE_LITTLE<<RSC_BE))\r
// Lazy RSC in kernel: enabled, little endian, pl = 0, lazy mode\r
#define RSC_KERNEL_LAZ ((RSC_MODE_LY<<RSC_MODE) | (RSC_BE_LITTLE<<RSC_BE))\r
// RSE disabled: disabled, pl = 0, little endian, eager mode\r
#define RSC_KERNEL_DISABLED ((RSC_MODE_LY<<RSC_MODE) | (RSC_BE_LITTLE<<RSC_BE))\r
\r
\r
//VOID\r
//SwitchStack (\r
//    VOID    *ContinuationFunction,\r
//    UINTN   Parameter,\r
//    UINTN   NewTopOfStack,\r
//    UINTN   NewBSPStore OPTIONAL\r
//)\r
///*++\r
//\r
//Input Arguments\r
//\r
//  ContinuationFunction - This is a pointer to the PLABEL of the function that should  be called once the\r
//        new stack has been created.  \r
//  Parameter - The parameter to pass to the continuation function\r
//  NewTopOfStack - This is the new top of the memory stack for ensuing code.  This is mandatory and\r
//      should be non-zero\r
//  NewBSPStore - This is the new BSP store for the ensuing code.  It is optional on IA-32 and mandatory on Itanium-based platform.\r
//\r
//--*/\r
\r
PROCEDURE_ENTRY(SwitchStack)\r
\r
        mov        r16 = -0x10;;\r
        and        r16 = r34, r16;;             // get new stack value in R16, 0 the last nibble.\r
        mov        r15 = r35;;                  // Get new BspStore into R15\r
        mov        r13 = r32;;                  // this is a pointer to the PLABEL of the continuation function.  \r
        mov        r17 = r33;;                  // this is the parameter to pass to the continuation function\r
\r
        alloc       r11=0,0,0,0                 // Set 0-size frame\r
        ;;\r
        flushrs;;\r
\r
        mov         r21 = RSC_KERNEL_DISABLED   // for rse disable             \r
        ;;\r
        mov         ar.rsc = r21                // turn off RSE                \r
\r
        add         sp = r0, r16;;              // transfer to the EFI stack\r
        mov         ar.bspstore = r15           // switch to EFI BSP        \r
        invala                                  // change of ar.bspstore needs invala.     \r
      \r
        mov         r18 = RSC_KERNEL_LAZ        // RSC enabled, Lazy mode\r
        ;;\r
        mov         ar.rsc = r18                // turn rse on, in kernel mode     \r
        ;;        \r
        alloc       r11=0,0,1,0;;               // alloc 0 outs going to ensuing DXE IPL service\r
        mov         out0 = r17\r
        ld8         r16 = [r13],8;;             // r16 = address of continuation function from the PLABEL\r
        ld8         gp = [r13]                  // gp  = gp of continuation function from the PLABEL\r
        mov         b6 = r16\r
        ;;\r
        br.call.sptk.few b0=b6;;                // Call the continuation function\r
        ;;\r
PROCEDURE_EXIT(SwitchStack)\r
\r
\r