| 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 | #ifdef HAVE_STRING_H |
| 27 | #include <string.h> |
| 28 | #else |
| 29 | #ifdef HAVE_STRINGS_H |
| 30 | #include <strings.h> |
| 31 | #endif |
| 32 | #endif |
| 33 | |
| 34 | #include <sys/ipc.h> |
| 35 | #include <sys/shm.h> |
| 36 | |
| 37 | |
| 38 | /* DEVICE |
| 39 | |
| 40 | |
| 41 | shm - map unix shared memory into psim address space |
| 42 | |
| 43 | |
| 44 | DESCRIPTION |
| 45 | |
| 46 | |
| 47 | This device implements an area of memory which is mapped into UNIX |
| 48 | shared memory. |
| 49 | |
| 50 | |
| 51 | PROPERTIES |
| 52 | |
| 53 | |
| 54 | reg = <address> <size> (required) |
| 55 | |
| 56 | Determine where the memory lives in the parents address space. |
| 57 | The SHM area is assumed to be of the same length. |
| 58 | |
| 59 | key = <integer> (required) |
| 60 | |
| 61 | This is the key of the unix shared memory area. |
| 62 | |
| 63 | EXAMPLES |
| 64 | |
| 65 | |
| 66 | Enable tracing of the shm: |
| 67 | |
| 68 | | bash$ psim -t shm-device \ |
| 69 | |
| 70 | |
| 71 | Configure a 512 kilobytes of UNIX shared memory with the key 0x12345678 |
| 72 | mapped into psim address space at 0x0c000000. |
| 73 | |
| 74 | | -o '/shm@0x0c000000/reg 0x0c000000 0x80000' \ |
| 75 | | -o '/shm@0x0c000000/key 0x12345678' \ |
| 76 | |
| 77 | sim/ppc/run -o '/#address-cells 1' \ |
| 78 | -o '/shm@0x0c000000/reg 0x0c000000 0x80000' \ |
| 79 | -o '/shm@0x0c000000/key 0x12345678' ../psim-hello/hello |
| 80 | |
| 81 | BUGS |
| 82 | |
| 83 | None known. |
| 84 | |
| 85 | */ |
| 86 | |
| 87 | typedef struct _hw_shm_device { |
| 88 | unsigned_word physical_address; |
| 89 | char *shm_address; |
| 90 | unsigned sizeof_memory; |
| 91 | key_t key; |
| 92 | int id; |
| 93 | } hw_shm_device; |
| 94 | |
| 95 | static void |
| 96 | hw_shm_init_data(device *me) |
| 97 | { |
| 98 | hw_shm_device *shm = (hw_shm_device*)device_data(me); |
| 99 | const device_unit *d; |
| 100 | reg_property_spec reg; |
| 101 | int i; |
| 102 | |
| 103 | /* Obtain the Key Value */ |
| 104 | if (device_find_property(me, "key") == NULL) |
| 105 | error("shm_init_data() required key property is missing\n"); |
| 106 | |
| 107 | shm->key = (key_t) device_find_integer_property(me, "key"); |
| 108 | DTRACE(shm, ("shm key (0x%08x)\n", shm->key) ); |
| 109 | |
| 110 | /* Figure out where this memory is in address space and how long it is */ |
| 111 | if ( !device_find_reg_array_property(me, "reg", 0, ®) ) |
| 112 | error("hw_shm_init_data() no address registered\n"); |
| 113 | |
| 114 | /* Determine the address and length being as paranoid as possible */ |
| 115 | shm->physical_address = 0xffffffff; |
| 116 | shm->sizeof_memory = 0xffffffff; |
| 117 | |
| 118 | for ( i=0 ; i<reg.address.nr_cells; i++ ) { |
| 119 | if (reg.address.cells[0] == 0 && reg.size.cells[0] == 0) |
| 120 | continue; |
| 121 | |
| 122 | if ( shm->physical_address != 0xffffffff ) |
| 123 | device_error(me, "Only single celled address ranges supported\n"); |
| 124 | |
| 125 | shm->physical_address = reg.address.cells[i]; |
| 126 | DTRACE(shm, ("shm physical_address=0x%x\n", shm->physical_address)); |
| 127 | |
| 128 | shm->sizeof_memory = reg.size.cells[i]; |
| 129 | DTRACE(shm, ("shm length=0x%x\n", shm->sizeof_memory)); |
| 130 | } |
| 131 | |
| 132 | if ( shm->physical_address == 0xffffffff ) |
| 133 | device_error(me, "Address not specified\n" ); |
| 134 | |
| 135 | if ( shm->sizeof_memory == 0xffffffff ) |
| 136 | device_error(me, "Length not specified\n" ); |
| 137 | |
| 138 | /* Now actually attach to or create the shared memory area */ |
| 139 | shm->id = shmget(shm->key, shm->sizeof_memory, IPC_CREAT | 0660); |
| 140 | if (shm->id == -1) |
| 141 | error("hw_shm_init_data() shmget failed\n"); |
| 142 | |
| 143 | shm->shm_address = shmat(shm->id, (char *)0, SHM_RND); |
| 144 | if (shm->shm_address == (void *)-1) |
| 145 | error("hw_shm_init_data() shmat failed\n"); |
| 146 | } |
| 147 | |
| 148 | static void |
| 149 | hw_shm_attach_address_callback(device *me, |
| 150 | attach_type attach, |
| 151 | int space, |
| 152 | unsigned_word addr, |
| 153 | unsigned nr_bytes, |
| 154 | access_type access, |
| 155 | device *client) /*callback/default*/ |
| 156 | { |
| 157 | hw_shm_device *shm = (hw_shm_device*)device_data(me); |
| 158 | |
| 159 | if (space != 0) |
| 160 | error("shm_attach_address_callback() invalid address space\n"); |
| 161 | |
| 162 | if (nr_bytes == 0) |
| 163 | error("shm_attach_address_callback() invalid size\n"); |
| 164 | } |
| 165 | |
| 166 | |
| 167 | static unsigned |
| 168 | hw_shm_io_read_buffer(device *me, |
| 169 | void *dest, |
| 170 | int space, |
| 171 | unsigned_word addr, |
| 172 | unsigned nr_bytes, |
| 173 | cpu *processor, |
| 174 | unsigned_word cia) |
| 175 | { |
| 176 | hw_shm_device *shm = (hw_shm_device*)device_data(me); |
| 177 | |
| 178 | /* do we need to worry about out of range addresses? */ |
| 179 | |
| 180 | DTRACE(shm, ("read %p %x %x %x\n", \ |
| 181 | shm->shm_address, shm->physical_address, addr, nr_bytes) ); |
| 182 | |
| 183 | memcpy(dest, &shm->shm_address[addr - shm->physical_address], nr_bytes); |
| 184 | return nr_bytes; |
| 185 | } |
| 186 | |
| 187 | |
| 188 | static unsigned |
| 189 | hw_shm_io_write_buffer(device *me, |
| 190 | const void *source, |
| 191 | int space, |
| 192 | unsigned_word addr, |
| 193 | unsigned nr_bytes, |
| 194 | cpu *processor, |
| 195 | unsigned_word cia) |
| 196 | { |
| 197 | hw_shm_device *shm = (hw_shm_device*)device_data(me); |
| 198 | |
| 199 | /* do we need to worry about out of range addresses? */ |
| 200 | |
| 201 | DTRACE(shm, ("write %p %x %x %x\n", \ |
| 202 | shm->shm_address, shm->physical_address, addr, nr_bytes) ); |
| 203 | |
| 204 | memcpy(&shm->shm_address[addr - shm->physical_address], source, nr_bytes); |
| 205 | return nr_bytes; |
| 206 | } |
| 207 | |
| 208 | static device_callbacks const hw_shm_callbacks = { |
| 209 | { generic_device_init_address, hw_shm_init_data }, |
| 210 | { hw_shm_attach_address_callback, }, /* address */ |
| 211 | { hw_shm_io_read_buffer, |
| 212 | hw_shm_io_write_buffer }, /* IO */ |
| 213 | { NULL, }, /* DMA */ |
| 214 | { NULL, }, /* interrupt */ |
| 215 | { NULL, }, /* unit */ |
| 216 | NULL, |
| 217 | }; |
| 218 | |
| 219 | static void * |
| 220 | hw_shm_create(const char *name, |
| 221 | const device_unit *unit_address, |
| 222 | const char *args) |
| 223 | { |
| 224 | hw_shm_device *shm = ZALLOC(hw_shm_device); |
| 225 | return shm; |
| 226 | } |
| 227 | |
| 228 | |
| 229 | |
| 230 | const device_descriptor hw_shm_device_descriptor[] = { |
| 231 | { "shm", hw_shm_create, &hw_shm_callbacks }, |
| 232 | { NULL }, |
| 233 | }; |
| 234 | |
| 235 | #endif /* _HW_SHM_C_ */ |