1. Torsten Alt, Kjetil Ullaland, Matthias Richter, Ketil Røed, Johan Alme
TPC Firmware on DCS
Torsten Alt, Kjetil Ullaland, Matthias Richter, Ketil Røed, Johan Alme
TPC Electronics meeting. CERN Jan 2005

2. Overview RCU 3 solution DCS RCU communication
Changes proposed to suit the new challenge with configuring.
Status

3. RCU 3 solution Modules Ethernet: TTCrx FPGA Config ADC readout
Provides access to the ethernet
TTCrx
Interface to the TTCrx Chip
Write/read registers over I2C
Maps all the TTCrx registers in a register file in the PLD
Decodes L2a/r messages. In case of a L2a message the trigger information is directly transferred over the RCU bus to the Data Assembler module.
FPGA Config
Configures the RCU-FPGA.
ADC readout
Monitors the voltages on the DCS
JTAG Master
Configures neighbour DCS cards.

4. DCS-RCU Communication
The communication between linux (dcs-driver) and RCU modules is done by using messages.
A message is written to the memories in the DCS FPGA, and the DCS messagebuffer translates this into RCU-bus commands.
Results on the RCU bus is translated back to a message that the dcs-driver can interpret.
In the existing solution the same memories are used for configuration of the RCU FPGA.

5. Proposed changes TTCrx IF is moved to RCU.
Serial B Channel will be used for data transmission.
Configuring & status of TTCrx will still be on DCS FPGA using I2C interface.
Reason:
Remove the FPGA on the DCS board from the datapath.
Configuring of RCU FPGA is changed.
New data interface for shipping and receiving configuration data.
Easier interface for programming both FPGA and Flash.
Faster
Less logic
Configuration tasks is mainly handled by the CPLD on the RCU.
The DCS Messagebuffer system and the RCU bus will not change.

6. DCS-RCU Communication
Two bus modes:
Memory mapped mode. (normal)
Transport data interface
Used for transport of configuration data.
Directly controlled from linux.

7. DCS-RCU Communication
The different instances of the driver (divided by minor-number), maps to different locations on the RCU card

8. Transport data interface
The transport data interface is used for transporting configuration data direct from linux.
32-bit asynchronous bus.
Same physical bus lines as the RCU bus.
Between the RCU CPLD and the DCS card.
Control signal DCS_ctrl[7] is used for switching between Memory mapped bus mode and trasnport bus mode.
The CPLD then translates the data into a format understandable for the selectMap bus or the Flash communication.
One control signal (dcs_ctrl[6]) is used to select selectMap IF or Flash.
6 control signals.

9. Transport data interface (DCS-CPLD 32 bit data interface)
(Configure_n)
Jeg tror jeg må endre busen litt her.. Er ikke helt riktig. Eller den er rett, men jeg må endre forklaringen. Data må klokkes inn på rising edge.
Note. If writing to or reading from flash, the first block of data is always the start address in the memory.

10. Data Format – Transport data interface
SelectMap:
Data is pushed 32 bit at the time
Flash
Number of bytes
Address in Flash
Data

11. Device driver
On the DCS, the transport data interface is controlled directly by the DCS driver.
The DCS driver is a device driver that is divided by minor number into different instances depending on use.
RCU bus driver
Virtex configuration driver
Complete interface to selectMap interface in CPLD, including controllines to choose correct bus mode
Makes it possible to configure the Virtex-II with a simple cat-command
Flash configuration drivers
Complete interface to flash interface in CPLD, including control lines to choose correct bus mode.
Makes it possible to write to a designated address in the flash memory on the RCU board with a simple cat-command

12. Status DCS messagebuffer is finished (T Alt).
Prototype device driver Virtex_driver is finished.
Ongoing work:
ADC interfaces
TTCrx control module
Prototype of Flash device driver
Configuration firmware