MTCA dummy kernel driver

The driver provides an interface compatible to the pcieuni driver and can be used in tests instead of real hardwarte

It provides 7 devices * mtcadummys0 to mtcadummys3 * llrfdummys4 * noioctldummys5 * pcieunidummys6

All provide 32 32bit registers in bar 0 and 4096 bytes of DMA data in bar 2.

Differences between the devices

TBD

Special registers

All devices provide a rudimentary emulation of firmware in bar 0: Register name | Address | Description ------------- | --------|----- WORDFIRMWARE | 0x00000000 | Major version of the kernel module, ro WORDCOMPILATION | 0x00000004 | Minor version of the kernel module, ro WORDSTATUS | 0x00000008 | User status register, rw WORDUSER | 0x0000000C | User register, rw WORDCLKCNT | 0x00000010 | 1D register with 2 words WORDCLKCNT0 | 0x00000010 WORDCLKCNT1 | 0x00000014 WORDCLKMUX | 0x00000020 | 1D register with 4 words WORDCLKMUX0 | 0x00000020 WORDCLKMUX1 | 0x00000024 WORDCLKMUX2 | 0x00000028 WORDCLKMUX3 | 0x0000002C WORDDUMMY | 0x0000003C | Contains "DMMY" as ASCII, ro WORDCLKRST | 0x00000040 | Clears all values in WORDCLKCNT and WORDCLKMUX if set to 1, rw WORDADCENA | 0x00000044 | Trigger generation of a parabola in the DMA data if set to 1, rw BROKENREGISTER | 0x00000048 | Fails read and write BROKEN_WRITE | 0x0000004C | Fails write

SPI handshaking emulation

These three registers simulate the SPI handshaing behavior as used e.g. in MotorDriverCard

Register name | Address | Description ------------- | --------|----- WORDSPIWRITE | 0x00000050 | Write data if SPISYNC was set to SYNCREQUESTED (0xFF). WORDSPIREAD | 0x00000054 | Will contain what was written to WORDSPIWRITE if WORDSPISYNC was set to SYNCREQUESTED and SPI was not configured to fail before the write, untouched otherwise WORDSPISYNC | 0x00000058 | Set to SYNCREQUESTED (0xFF) before writing to WORDSPIWRITE for a successful write. Will be reset to 0 after successful write, to SYNC_ERROR (0xAA) otherwise.

Querying the current state

``` Device 0 not in use.

Device 1 not in use.

Device 2 not in use.

Device 3 not in use.

Device 4 not in use.

Device 5 not in use.

Device 6 System Bar: Register Contenthex Contentdec: 0x00000000 0x00000000 0 0x00000001 0x00000009 9 0x00000002 0x00000000 0 0x00000003 0x00000000 0 0x00000004 0x00000019 25 0x00000005 0x00000000 0 0x00000006 0x00000000 0 0x00000007 0x00000000 0 0x00000008 0x00000000 0 0x00000009 0x00000000 0 0x0000000A 0x00000000 0 0x0000000B 0x00000000 0 0x0000000C 0x00000000 0 0x0000000D 0x00000000 0 0x0000000E 0x00000000 0 0x0000000F 0x444D4D59 1145916761 0x00000010 0x00000000 0 0x00000011 0x00000001 1 0x00000012 0x0000002A 42 0x00000013 0x0000002A 42 0x00000014 0x15000000 352321536 0x00000015 0x15000000 352321536 0x00000016 0x00000000 0 0x00000017 0x00000000 0 0x00000018 0x00000000 0 0x00000019 0x00000000 0 0x0000001A 0x00000000 0 0x0000001B 0x00000000 0 0x0000001C 0x00000000 0 0x0000001D 0x00000000 0 0x0000001E 0x00000000 0 0x0000001F 0x00000000 0

Device 6 DMA Bar: Offset Content[offset] Content[offset+0x4] Content[offset+0x8] Content[offset+0xC]: 0x00000000 0x00000000 0x00000001 0x00000004 0x00000009 0x00000010 0x00000010 0x00000019 0x00000024 0x00000031 0x00000020 0x00000040 0x00000051 0x00000064 0x00000079 0x00000030 0x00000090 0x000000A9 0x000000C4 0x000000E1 0x00000040 0x00000100 0x00000121 0x00000144 0x00000169 0x00000050 0x00000190 0x000001B9 0x000001E4 0x00000211 0x00000060 0x00000240 0x00000000 0x00000000 0x00000000 0x00000070 0x00000000 0x00000000 0x00000000 0x00000000 0x00000080 0x00000000 0x00000000 0x00000000 0x00000000 0x00000090 0x00000000 0x00000000 0x00000000 0x00000000 0x000000A0 0x00000000 0x00000000 0x00000000 0x00000000 0x000000B0 0x00000000 0x00000000 0x00000000 0x00000000 0x000000C0 0x00000000 0x00000000 0x00000000 0x00000000 0x000000D0 0x00000000 0x00000000 0x00000000 0x00000000 ... `` It is possible to dump the register contents of each device by callingcat /proc/mtcadummy`

Behavior control

In addition to the special registers mentioned above, it is possible to control whether or not certain operations will produce an error by writing to /proc/mtcadummy.

Eg. echo open:1 >/proc/mtcadummy will cause all following attempts to open a device to fail. Calling echo "open:0 spi:1" >/proc/mtcadummy will then enable opening but force any SPI request to fail. It is possible to send up to 255 characters to the device. If options are sent multiple times, the last option sent will win.

Available options

Option | Description -------|------------ open | If set to 1, open() calls on the device will fail read | If set to 1, read() calls on the device will fail write | If set to 1, write() calls on the device will fail spi | If set to 1, the SPI simulation will fail.