1 /* This file is part of the program psim. 2 3 Copyright (C) 1997,2008, Joel Sherrill <joel@OARcorp.com> 4 5 This program is free software; you can redistribute it and/or modify 6 it under the terms of the GNU General Public License as published by 7 the Free Software Foundation; either version 3 of the License, or 8 (at your option) any later version. 9 10 This program is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 GNU General Public License for more details. 14 15 You should have received a copy of the GNU General Public License 16 along with this program; if not, see <http://www.gnu.org/licenses/>. 17 18 */ 19 20 21 #ifndef _HW_SHM_C_ 22 #define _HW_SHM_C_ 23 24 #include "device_table.h" 25 26 #include <string.h> 27 #include <sys/ipc.h> 28 #include <sys/shm.h> 29 30 31 /* DEVICE 32 33 34 shm - map unix shared memory into psim address space 35 36 37 DESCRIPTION 38 39 40 This device implements an area of memory which is mapped into UNIX 41 shared memory. 42 43 44 PROPERTIES 45 46 47 reg = <address> <size> (required) 48 49 Determine where the memory lives in the parents address space. 50 The SHM area is assumed to be of the same length. 51 52 key = <integer> (required) 53 54 This is the key of the unix shared memory area. 55 56 EXAMPLES 57 58 59 Enable tracing of the shm: 60 61 | bash$ psim -t shm-device \ 62 63 64 Configure a 512 kilobytes of UNIX shared memory with the key 0x12345678 65 mapped into psim address space at 0x0c000000. 66 67 | -o '/shm@0x0c000000/reg 0x0c000000 0x80000' \ 68 | -o '/shm@0x0c000000/key 0x12345678' \ 69 70 sim/ppc/run -o '/#address-cells 1' \ 71 -o '/shm@0x0c000000/reg 0x0c000000 0x80000' \ 72 -o '/shm@0x0c000000/key 0x12345678' ../psim-hello/hello 73 74 BUGS 75 76 None known. 77 78 */ 79 80 #ifdef HAVE_SYSV_SHM 81 82 typedef struct _hw_shm_device { 83 unsigned_word physical_address; 84 char *shm_address; 85 unsigned sizeof_memory; 86 key_t key; 87 int id; 88 } hw_shm_device; 89 90 static void 91 hw_shm_init_data(device *me) 92 { 93 hw_shm_device *shm = (hw_shm_device*)device_data(me); 94 reg_property_spec reg; 95 int i; 96 97 /* Obtain the Key Value */ 98 if (device_find_property(me, "key") == NULL) 99 error("shm_init_data() required key property is missing\n"); 100 101 shm->key = (key_t) device_find_integer_property(me, "key"); 102 DTRACE(shm, ("shm key (0x%08jx)\n", (intmax_t)shm->key) ); 103 104 /* Figure out where this memory is in address space and how long it is */ 105 if ( !device_find_reg_array_property(me, "reg", 0, ®) ) 106 error("hw_shm_init_data() no address registered\n"); 107 108 /* Determine the address and length being as paranoid as possible */ 109 shm->physical_address = 0xffffffff; 110 shm->sizeof_memory = 0xffffffff; 111 112 for ( i=0 ; i<reg.address.nr_cells; i++ ) { 113 if (reg.address.cells[0] == 0 && reg.size.cells[0] == 0) 114 continue; 115 116 if ( shm->physical_address != 0xffffffff ) 117 device_error(me, "Only single celled address ranges supported\n"); 118 119 shm->physical_address = reg.address.cells[i]; 120 DTRACE(shm, ("shm physical_address=0x%x\n", shm->physical_address)); 121 122 shm->sizeof_memory = reg.size.cells[i]; 123 DTRACE(shm, ("shm length=0x%x\n", shm->sizeof_memory)); 124 } 125 126 if ( shm->physical_address == 0xffffffff ) 127 device_error(me, "Address not specified\n" ); 128 129 if ( shm->sizeof_memory == 0xffffffff ) 130 device_error(me, "Length not specified\n" ); 131 132 /* Now actually attach to or create the shared memory area */ 133 shm->id = shmget(shm->key, shm->sizeof_memory, IPC_CREAT | 0660); 134 if (shm->id == -1) 135 error("hw_shm_init_data() shmget failed\n"); 136 137 shm->shm_address = shmat(shm->id, (char *)0, SHM_RND); 138 if (shm->shm_address == (void *)-1) 139 error("hw_shm_init_data() shmat failed\n"); 140 } 141 142 static void 143 hw_shm_attach_address_callback(device *me, 144 attach_type attach, 145 int space, 146 unsigned_word addr, 147 unsigned nr_bytes, 148 access_type access, 149 device *client) /*callback/default*/ 150 { 151 if (space != 0) 152 error("shm_attach_address_callback() invalid address space\n"); 153 154 if (nr_bytes == 0) 155 error("shm_attach_address_callback() invalid size\n"); 156 } 157 158 159 static unsigned 160 hw_shm_io_read_buffer(device *me, 161 void *dest, 162 int space, 163 unsigned_word addr, 164 unsigned nr_bytes, 165 cpu *processor, 166 unsigned_word cia) 167 { 168 hw_shm_device *shm = (hw_shm_device*)device_data(me); 169 170 /* do we need to worry about out of range addresses? */ 171 172 DTRACE(shm, ("read %p %x %x %x\n", \ 173 shm->shm_address, shm->physical_address, addr, nr_bytes) ); 174 175 memcpy(dest, &shm->shm_address[addr - shm->physical_address], nr_bytes); 176 return nr_bytes; 177 } 178 179 180 static unsigned 181 hw_shm_io_write_buffer(device *me, 182 const void *source, 183 int space, 184 unsigned_word addr, 185 unsigned nr_bytes, 186 cpu *processor, 187 unsigned_word cia) 188 { 189 hw_shm_device *shm = (hw_shm_device*)device_data(me); 190 191 /* do we need to worry about out of range addresses? */ 192 193 DTRACE(shm, ("write %p %x %x %x\n", \ 194 shm->shm_address, shm->physical_address, addr, nr_bytes) ); 195 196 memcpy(&shm->shm_address[addr - shm->physical_address], source, nr_bytes); 197 return nr_bytes; 198 } 199 200 static device_callbacks const hw_shm_callbacks = { 201 { generic_device_init_address, hw_shm_init_data }, 202 { hw_shm_attach_address_callback, }, /* address */ 203 { hw_shm_io_read_buffer, 204 hw_shm_io_write_buffer }, /* IO */ 205 { NULL, }, /* DMA */ 206 { NULL, }, /* interrupt */ 207 { NULL, }, /* unit */ 208 NULL, 209 }; 210 211 static void * 212 hw_shm_create(const char *name, 213 const device_unit *unit_address, 214 const char *args) 215 { 216 hw_shm_device *shm = ZALLOC(hw_shm_device); 217 return shm; 218 } 219 220 221 222 const device_descriptor hw_shm_device_descriptor[] = { 223 { "shm", hw_shm_create, &hw_shm_callbacks }, 224 { NULL }, 225 }; 226 227 #else 228 229 const device_descriptor hw_shm_device_descriptor[] = { 230 { NULL }, 231 }; 232 233 #endif /* HAVE_SYSV_SHM */ 234 235 #endif /* _HW_SHM_C_ */ 236