drivers/gpu/drm/vmwgfx/vmwgfx_msg.h

   1 /* SPDX-License-Identifier: GPL-2.0+ OR MIT */
   2 /**************************************************************************
   3  *
   4  * Copyright 2016 VMware, Inc., Palo Alto, CA., USA
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the
   8  * "Software"), to deal in the Software without restriction, including
   9  * without limitation the rights to use, copy, modify, merge, publish,
  10  * distribute, sub license, and/or sell copies of the Software, and to
  11  * permit persons to whom the Software is furnished to do so, subject to
  12  * the following conditions:
  13  *
  14  * The above copyright notice and this permission notice (including the
  15  * next paragraph) shall be included in all copies or substantial portions
  16  * of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
  21  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
  22  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  23  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  24  * USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  **************************************************************************
  27  *
  28  * Based on code from vmware.c and vmmouse.c.
  29  * Author:
  30  *   Sinclair Yeh <syeh@vmware.com>
  31  */
  32 #ifndef _VMWGFX_MSG_H
  33 #define _VMWGFX_MSG_H
  34
  35
  36 /**
  37  * Hypervisor-specific bi-directional communication channel.  Should never
  38  * execute on bare metal hardware.  The caller must make sure to check for
  39  * supported hypervisor before using these macros.
  40  *
  41  * The last two parameters are both input and output and must be initialized.
  42  *
  43  * @cmd: [IN] Message Cmd
  44  * @in_ebx: [IN] Message Len, through EBX
  45  * @in_si: [IN] Input argument through SI, set to 0 if not used
  46  * @in_di: [IN] Input argument through DI, set ot 0 if not used
  47  * @port_num: [IN] port number + [channel id]
  48  * @magic: [IN] hypervisor magic value
  49  * @eax: [OUT] value of EAX register
  50  * @ebx: [OUT] e.g. status from an HB message status command
  51  * @ecx: [OUT] e.g. status from a non-HB message status command
  52  * @edx: [OUT] e.g. channel id
  53  * @si:  [OUT]
  54  * @di:  [OUT]
  55  */
  56 #define VMW_PORT(cmd, in_ebx, in_si, in_di,     \
  57                  port_num, magic,               \
  58                  eax, ebx, ecx, edx, si, di)    \
  59 ({                                              \
  60         asm volatile ("inl %%dx, %%eax;" :      \
  61                 "=a"(eax),                      \
  62                 "=b"(ebx),                      \
  63                 "=c"(ecx),                      \
  64                 "=d"(edx),                      \
  65                 "=S"(si),                       \
  66                 "=D"(di) :                      \
  67                 "a"(magic),                     \
  68                 "b"(in_ebx),                    \
  69                 "c"(cmd),                       \
  70                 "d"(port_num),                  \
  71                 "S"(in_si),                     \
  72                 "D"(in_di) :                    \
  73                 "memory");                      \
  74 })
  75
  76
  77 /**
  78  * Hypervisor-specific bi-directional communication channel.  Should never
  79  * execute on bare metal hardware.  The caller must make sure to check for
  80  * supported hypervisor before using these macros.
  81  *
  82  * The last 3 parameters are both input and output and must be initialized.
  83  *
  84  * @cmd: [IN] Message Cmd
  85  * @in_ecx: [IN] Message Len, through ECX
  86  * @in_si: [IN] Input argument through SI, set to 0 if not used
  87  * @in_di: [IN] Input argument through DI, set to 0 if not used
  88  * @port_num: [IN] port number + [channel id]
  89  * @magic: [IN] hypervisor magic value
  90  * @bp:  [IN]
  91  * @eax: [OUT] value of EAX register
  92  * @ebx: [OUT] e.g. status from an HB message status command
  93  * @ecx: [OUT] e.g. status from a non-HB message status command
  94  * @edx: [OUT] e.g. channel id
  95  * @si:  [OUT]
  96  * @di:  [OUT]
  97  */
  98 #ifdef __x86_64__
  99
 100 #define VMW_PORT_HB_OUT(cmd, in_ecx, in_si, in_di,      \
 101                         port_num, magic, bp,            \
 102                         eax, ebx, ecx, edx, si, di)     \
 103 ({                                                      \
 104         asm volatile ("push %%rbp;"                     \
 105                 "mov %12, %%rbp;"                       \
 106                 "rep outsb;"                            \
 107                 "pop %%rbp;" :                          \
 108                 "=a"(eax),                              \
 109                 "=b"(ebx),                              \
 110                 "=c"(ecx),                              \
 111                 "=d"(edx),                              \
 112                 "=S"(si),                               \
 113                 "=D"(di) :                              \
 114                 "a"(magic),                             \
 115                 "b"(cmd),                               \
 116                 "c"(in_ecx),                            \
 117                 "d"(port_num),                          \
 118                 "S"(in_si),                             \
 119                 "D"(in_di),                             \
 120                 "r"(bp) :                               \
 121                 "memory", "cc");                        \
 122 })
 123
 124
 125 #define VMW_PORT_HB_IN(cmd, in_ecx, in_si, in_di,       \
 126                        port_num, magic, bp,             \
 127                        eax, ebx, ecx, edx, si, di)      \
 128 ({                                                      \
 129         asm volatile ("push %%rbp;"                     \
 130                 "mov %12, %%rbp;"                       \
 131                 "rep insb;"                             \
 132                 "pop %%rbp" :                           \
 133                 "=a"(eax),                              \
 134                 "=b"(ebx),                              \
 135                 "=c"(ecx),                              \
 136                 "=d"(edx),                              \
 137                 "=S"(si),                               \
 138                 "=D"(di) :                              \
 139                 "a"(magic),                             \
 140                 "b"(cmd),                               \
 141                 "c"(in_ecx),                            \
 142                 "d"(port_num),                          \
 143                 "S"(in_si),                             \
 144                 "D"(in_di),                             \
 145                 "r"(bp) :                               \
 146                 "memory", "cc");                        \
 147 })
 148
 149 #else
 150
 151 /*
 152  * In the 32-bit version of this macro, we store bp in a memory location
 153  * because we've ran out of registers.
 154  * Now we can't reference that memory location while we've modified
 155  * %esp or %ebp, so we first push it on the stack, just before we push
 156  * %ebp, and then when we need it we read it from the stack where we
 157  * just pushed it.
 158  */
 159 #define VMW_PORT_HB_OUT(cmd, in_ecx, in_si, in_di,      \
 160                         port_num, magic, bp,            \
 161                         eax, ebx, ecx, edx, si, di)     \
 162 ({                                                      \
 163         asm volatile ("push %12;"                       \
 164                 "push %%ebp;"                           \
 165                 "mov 0x04(%%esp), %%ebp;"               \
 166                 "rep outsb;"                            \
 167                 "pop %%ebp;"                            \
 168                 "add $0x04, %%esp;" :                   \
 169                 "=a"(eax),                              \
 170                 "=b"(ebx),                              \
 171                 "=c"(ecx),                              \
 172                 "=d"(edx),                              \
 173                 "=S"(si),                               \
 174                 "=D"(di) :                              \
 175                 "a"(magic),                             \
 176                 "b"(cmd),                               \
 177                 "c"(in_ecx),                            \
 178                 "d"(port_num),                          \
 179                 "S"(in_si),                             \
 180                 "D"(in_di),                             \
 181                 "m"(bp) :                               \
 182                 "memory", "cc");                        \
 183 })
 184
 185
 186 #define VMW_PORT_HB_IN(cmd, in_ecx, in_si, in_di,       \
 187                        port_num, magic, bp,             \
 188                        eax, ebx, ecx, edx, si, di)      \
 189 ({                                                      \
 190         asm volatile ("push %12;"                       \
 191                 "push %%ebp;"                           \
 192                 "mov 0x04(%%esp), %%ebp;"               \
 193                 "rep insb;"                             \
 194                 "pop %%ebp;"                            \
 195                 "add $0x04, %%esp;" :                   \
 196                 "=a"(eax),                              \
 197                 "=b"(ebx),                              \
 198                 "=c"(ecx),                              \
 199                 "=d"(edx),                              \
 200                 "=S"(si),                               \
 201                 "=D"(di) :                              \
 202                 "a"(magic),                             \
 203                 "b"(cmd),                               \
 204                 "c"(in_ecx),                            \
 205                 "d"(port_num),                          \
 206                 "S"(in_si),                             \
 207                 "D"(in_di),                             \
 208                 "m"(bp) :                               \
 209                 "memory", "cc");                        \
 210 })
 211 #endif /* #if __x86_64__ */
 212
 213 #endif