1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  */
  25 
  26 /*
  27  * Copyright 2019 Joyent, Inc.
  28  */
  29 
  30 #include <sys/asm_linkage.h>
  31 #include <sys/asm_misc.h>
  32 
  33 /*
  34  * Implementation as specific by ACPI 3.0 specification
  35  * section 5.2.10.1
  36  *
  37  * Global Lock Structure within the FACS 
  38  *
  39  * |-----------------------------------------------------------------------| 
  40  * |  Field  | Bit Length | Bit Offset |           Description             |
  41  * |---------|------------|------------|-----------------------------------| 
  42  * | Pending |     1      |     0      | Non-zero indicates that a request |
  43  * |         |            |            | for ownership of the global lock  |
  44  * |         |            |            | is pending.                       |
  45  * |---------|------------|------------|-----------------------------------| 
  46  * | Owned   |     1      |     1      | Non-zero indicates that the Global|
  47  * |         |            |            | lock is owned.                    |
  48  * |---------|------------|------------|-----------------------------------| 
  49  * | Reserved|     30     |     2      | Reserved for future use           |
  50  * |---------|------------|------------|-----------------------------------| 
  51  */
  52 
  53 /* Offset of GlobalLock element in FACS structure */
  54 #define GlobalLock      0x10
  55 
  56         ENTRY(__acpi_acquire_global_lock)
  57         movq    $0xff, %rax             / error return if FACS is null
  58         orq     %rdi, %rdi              / %rdi contains pointer to FACS
  59         jz      1f
  60         leaq    GlobalLock(%rdi), %rdi  / make %rdi point at the lock
  61 0:
  62         movl    (%rdi), %eax            / get current value of Global Lock
  63         movl    %eax, %edx
  64         andl    $0xFFFFFFFE, %edx       / Clear pending bit
  65         btsl    $1, %edx                / Check and set owner bit
  66         adcl    $0, %edx                / If owned, set pending bit
  67         lock
  68         cmpxchgl %edx, (%rdi)           / Attempt to set new value
  69         jnz     0b                      / If not set, try again
  70         cmpb    $3, %dl                 / Was it acquired or marked pending?
  71         sbbq    %rax, %rax              / acquired = -1, pending = 0
  72 1:
  73         ret
  74         SET_SIZE(__acpi_acquire_global_lock)
  75 
  76 
  77         ENTRY(__acpi_release_global_lock)
  78         xorq    %rax, %rax      / error return if FACS is null
  79         orq     %rdi, %rdi      / %rdi contains pointer to FACS
  80         jz      1f
  81         leaq    GlobalLock(%rdi), %rdi  / make %rdi point at the lock
  82 0:
  83         movl    (%rdi), %eax
  84         movl    %eax, %edx
  85         andl    $0xFFFFFFFC, %edx
  86         lock
  87         cmpxchgl %edx, (%rdi)
  88         jnz     0b
  89         andq    $1, %rax
  90 1:
  91         ret
  92         SET_SIZE(__acpi_release_global_lock)
  93 
  94 
  95 /*
  96  * execute WBINVD instruction
  97  */
  98 
  99         ENTRY(__acpi_wbinvd)
 100         wbinvd
 101         ret
 102         SET_SIZE(__acpi_wbinvd)
 103