Edwick: SZLUG April monthly meeting

why vxworks: see pro and con below
1. pro: simplicity, high quality code, document everything
2. con: proprietary, less existed package, inactive community
basic:
1. multi-tasking
2. inter-task
3. communication
4. mm(first-fit)
5. IO system, UNIX-like file/dir/device, POSIX AIO …
6. fs: dosFs, rawFs, tapeFs, cdromFs, TSFs, TrueFFS for flash devices
7. network: TCP/IP, 802.1x, IPSec, NAT/NAPT, OSPF, Firewall, PPP …
A glance of VxWorks
1. libdrv.a, libnet.a, libarch.a, libos.a, libwind.a
2. all = libxxx.a + BSP = libxxx.a + bootcode + basic device driver
bootcode: arch dependent code
1. Cache, TLB, GRs in CPU, CP0's regs, PLL, DDR
2. watchdog, Exception/Interrupt, RTC, GPIO
case 1: slow loop on SPI flash
case 2: busy stuck of interrupt
1. MIPS CPU has 4 general purpose timer
case 3: load delay shot on MIPS R3000
case 4: stochastically stuch when jumping to vxworks
case 5: stochastically soft reboot failure due to PLL switch
1. resolution x3
importance of bsp:
1. availablity
2. reliability
3. stability
4. performance
things bsp engineer need to know (!!!)
1. arch: Instuctions, Pipeline, cache, exception/interrupt
2. Mem: SDRAM, DDR, NOR/NAND
3. Bus: UART, JTAG, SPI
4. Misc: PLL, Timer, GPIO, watchdog, DMA
5. OS & toolchain
6. Debug: ICE, debugger
Time for questions:
1. cache coherency
2. SoC problem
3. how and how hard to be a bsp engineer