1/*
  2 * Copyright (C) 2016, VMware, Inc.
  3 *
  4 * This program is free software; you can redistribute it and/or modify
  5 * it under the terms of the GNU General Public License as published by
  6 * the Free Software Foundation; either version 2 of the License, or
  7 * (at your option) any later version.
  8 *
  9 * This program is distributed in the hope that it will be useful, but
 10 * WITHOUT ANY WARRANTY; without even the implied warranty of
 11 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
 12 * NON INFRINGEMENT.  See the GNU General Public License for more
 13 * details.
 14 *
 15 * Based on code from vmware.c and vmmouse.c.
 16 * Author:
 17 *   Sinclair Yeh <syeh@vmware.com>
 18 */
 19#ifndef _VMWGFX_MSG_H
 20#define _VMWGFX_MSG_H
 21
 22
 23/**
 24 * Hypervisor-specific bi-directional communication channel.  Should never
 25 * execute on bare metal hardware.  The caller must make sure to check for
 26 * supported hypervisor before using these macros.
 27 *
 28 * The last two parameters are both input and output and must be initialized.
 29 *
 30 * @cmd: [IN] Message Cmd
 31 * @in_ebx: [IN] Message Len, through EBX
 32 * @in_si: [IN] Input argument through SI, set to 0 if not used
 33 * @in_di: [IN] Input argument through DI, set ot 0 if not used
 34 * @port_num: [IN] port number + [channel id]
 35 * @magic: [IN] hypervisor magic value
 36 * @eax: [OUT] value of EAX register
 37 * @ebx: [OUT] e.g. status from an HB message status command
 38 * @ecx: [OUT] e.g. status from a non-HB message status command
 39 * @edx: [OUT] e.g. channel id
 40 * @si:  [OUT]
 41 * @di:  [OUT]
 42 */
 43#define VMW_PORT(cmd, in_ebx, in_si, in_di,	\
 44		 port_num, magic,		\
 45		 eax, ebx, ecx, edx, si, di)	\
 46({						\
 47	asm volatile ("inl %%dx, %%eax;" :	\
 48		"=a"(eax),			\
 49		"=b"(ebx),			\
 50		"=c"(ecx),			\
 51		"=d"(edx),			\
 52		"=S"(si),			\
 53		"=D"(di) :			\
 54		"a"(magic),			\
 55		"b"(in_ebx),			\
 56		"c"(cmd),			\
 57		"d"(port_num),			\
 58		"S"(in_si),			\
 59		"D"(in_di) :			\
 60		"memory");			\
 61})
 62
 63
 64/**
 65 * Hypervisor-specific bi-directional communication channel.  Should never
 66 * execute on bare metal hardware.  The caller must make sure to check for
 67 * supported hypervisor before using these macros.
 68 *
 69 * The last 3 parameters are both input and output and must be initialized.
 70 *
 71 * @cmd: [IN] Message Cmd
 72 * @in_ecx: [IN] Message Len, through ECX
 73 * @in_si: [IN] Input argument through SI, set to 0 if not used
 74 * @in_di: [IN] Input argument through DI, set to 0 if not used
 75 * @port_num: [IN] port number + [channel id]
 76 * @magic: [IN] hypervisor magic value
 77 * @bp:  [IN]
 78 * @eax: [OUT] value of EAX register
 79 * @ebx: [OUT] e.g. status from an HB message status command
 80 * @ecx: [OUT] e.g. status from a non-HB message status command
 81 * @edx: [OUT] e.g. channel id
 82 * @si:  [OUT]
 83 * @di:  [OUT]
 84 */
 85#ifdef __x86_64__
 86
 87#define VMW_PORT_HB_OUT(cmd, in_ecx, in_si, in_di,	\
 88			port_num, magic, bp,		\
 89			eax, ebx, ecx, edx, si, di)	\
 90({							\
 91	asm volatile ("push %%rbp;"			\
 92		"mov %12, %%rbp;"			\
 93		"rep outsb;"				\
 94		"pop %%rbp;" :				\
 95		"=a"(eax),				\
 96		"=b"(ebx),				\
 97		"=c"(ecx),				\
 98		"=d"(edx),				\
 99		"=S"(si),				\
100		"=D"(di) :				\
101		"a"(magic),				\
102		"b"(cmd),				\
103		"c"(in_ecx),				\
104		"d"(port_num),				\
105		"S"(in_si),				\
106		"D"(in_di),				\
107		"r"(bp) :				\
108		"memory", "cc");			\
109})
110
111
112#define VMW_PORT_HB_IN(cmd, in_ecx, in_si, in_di,	\
113		       port_num, magic, bp,		\
114		       eax, ebx, ecx, edx, si, di)	\
115({							\
116	asm volatile ("push %%rbp;"			\
117		"mov %12, %%rbp;"			\
118		"rep insb;"				\
119		"pop %%rbp" :				\
120		"=a"(eax),				\
121		"=b"(ebx),				\
122		"=c"(ecx),				\
123		"=d"(edx),				\
124		"=S"(si),				\
125		"=D"(di) :				\
126		"a"(magic),				\
127		"b"(cmd),				\
128		"c"(in_ecx),				\
129		"d"(port_num),				\
130		"S"(in_si),				\
131		"D"(in_di),				\
132		"r"(bp) :				\
133		"memory", "cc");			\
134})
135
136#else
137
138/*
139 * In the 32-bit version of this macro, we store bp in a memory location
140 * because we've ran out of registers.
141 * Now we can't reference that memory location while we've modified
142 * %esp or %ebp, so we first push it on the stack, just before we push
143 * %ebp, and then when we need it we read it from the stack where we
144 * just pushed it.
145 */
146#define VMW_PORT_HB_OUT(cmd, in_ecx, in_si, in_di,	\
147			port_num, magic, bp,		\
148			eax, ebx, ecx, edx, si, di)	\
149({							\
150	asm volatile ("push %12;"			\
151		"push %%ebp;"				\
152		"mov 0x04(%%esp), %%ebp;"		\
153		"rep outsb;"				\
154		"pop %%ebp;"				\
155		"add $0x04, %%esp;" :			\
156		"=a"(eax),				\
157		"=b"(ebx),				\
158		"=c"(ecx),				\
159		"=d"(edx),				\
160		"=S"(si),				\
161		"=D"(di) :				\
162		"a"(magic),				\
163		"b"(cmd),				\
164		"c"(in_ecx),				\
165		"d"(port_num),				\
166		"S"(in_si),				\
167		"D"(in_di),				\
168		"m"(bp) :				\
169		"memory", "cc");			\
170})
171
172
173#define VMW_PORT_HB_IN(cmd, in_ecx, in_si, in_di,	\
174		       port_num, magic, bp,		\
175		       eax, ebx, ecx, edx, si, di)	\
176({							\
177	asm volatile ("push %12;"			\
178		"push %%ebp;"				\
179		"mov 0x04(%%esp), %%ebp;"		\
180		"rep insb;"				\
181		"pop %%ebp;"				\
182		"add $0x04, %%esp;" :			\
183		"=a"(eax),				\
184		"=b"(ebx),				\
185		"=c"(ecx),				\
186		"=d"(edx),				\
187		"=S"(si),				\
188		"=D"(di) :				\
189		"a"(magic),				\
190		"b"(cmd),				\
191		"c"(in_ecx),				\
192		"d"(port_num),				\
193		"S"(in_si),				\
194		"D"(in_di),				\
195		"m"(bp) :				\
196		"memory", "cc");			\
197})
198#endif /* #if __x86_64__ */
199
200#endif