PowerPC and VXI

1
PowerPC and VXI

• Kinetic Systems V151
• Embedded PowerPC Slot-0 Controller

2
Objective

• Port the EPICS low-level RF code to another VXI
  slot-0 controller
• vxWorks 5.3.1 and EPICS R3.13.2
• Current cpu, niCpu030 has been discontinued
• Crate profile SLAC VXI register based modules
  and AB VME Scanner
• Why choose the PowerPC
• Pressure at SLAC to replace niCpu030
• Intel slot-0 controllers (NI) did not have
  favorable reviews
• Consistency one ppc architecture for VMEbus and
  VXIbus projects at SLAC
• byte orientation (big endian) is the same as the
  68K architecture of the niCpu030

3
Hardware Issues

• Elma crate power-on hang
• SYSRST not asserted on reboot
• D8/D16 IACK Cycle
• SLAC VXI modules and the VXI spec
• Interrupt controller uses a mechanism for
  autovectoring VME interrupts

4
Software Issues

• Learning about the VXIbus Standard as well the
  SLAC VXI register-based modules.
• Interrupts
• 1 Interrupt Level instead of 7 as with 68k
  Architectory
• Missing functions intVecGet
• Unsolicited Interrupt Handlers different naming
  standard
• VXI mode vs. VME mode
• Lack of atomic Read-Modify-Write
• VXI Library
• Incorrect and/or buggy library - Resman crashes
• Missing basic functions GetMyLA,SetMODID
• VXI library initialization
• A32 Space device window configuration
• EPICS_VXI_A32_BASE 0x20000000 0x9000000
• EPICS_VXI_A32_SIZE 0x00100000 0x1000000

5
Code Changes

• EPICS Code changed
• drvEpvxi.c,devLib.c,veclist.c table of
  unsolicited interrupts
• Crate a dummy isr
• static void vmeArgTbl 7
• devInterruptConnectVXI( level,isr,parm )
• dummyISR(controller,statusId,level)
• myVmeIsr( vmeArgTbl( vmeArgTbllevel-1
  ) )
• Bsp kernel changes
• Adding functionality sysBusTas,intVecGet
  (Andrew Johnson)
• VXI vs VME mode VXI/VME fighting for control of
  the bus
• sysUniverseIntHandler VXI vs VME mode
• sysVme.c - KSC method of taking control of VME
  interrupt autovectoring

t

6
Vector Table
0 ... 11 254 255
Handler
Argument
Next
PPC External Interrupt Vector 0x500
Universe VME Interrupt kscIntHandler sysUniverseIn
tHandler vxiBaseIsr
7
VXI Vector Table
Level ISR
1 DefaultVXIintHandler
2 DefaultVXIintHandler
3 DefaultVXIintHandler
4 DefaultVXIintHandler
5 DefaultVXIintHandler
6 DefaultVXIintHandler
7 DefaultVXIintHandler
8
Conclusions

• Prefer a BSP supported by the OS
• Ask for VXI library code
• Awaiting SLAC VXI board modification to recognize
  D8 IACK cycle