gsd_butterstick: Add initial DDR3 support.
Validated with:
./gsd_butterstick.py --uart-name=crossover --with-etherbone --csr-csv=csr.csv --build --load
litex_server --udp
litex_term bridge
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Build your hardware, easily!
(c) Copyright 2012-2021 Enjoy-Digital
(c) Copyright 2007-2015 M-Labs
BIOS built on Sep 1 2021 19:09:52
BIOS CRC passed (3d349845)
Migen git sha1: 27dbf03
LiteX git sha1: 315fbe18
--=============== SoC ==================--
CPU: VexRiscv @ 75MHz
BUS: WISHBONE 32-bit @ 4GiB
CSR: 32-bit data
ROM: 128KiB
SRAM: 8KiB
L2: 8KiB
SDRAM: 524288KiB 16-bit @ 300MT/s (CL-6 CWL-5)
--========== Initialization ============--
Initializing SDRAM @0x40000000...
Switching SDRAM to software control.
Read leveling:
m0, b00: |01110000| delays: 02+-01
m0, b01: |00000000| delays: -
m0, b02: |00000000| delays: -
m0, b03: |00000000| delays: -
best: m0, b00 delays: 02+-01
m1, b00: |01110000| delays: 02+-01
m1, b01: |00000000| delays: -
m1, b02: |00000000| delays: -
m1, b03: |00000000| delays: -
best: m1, b00 delays: 02+-01
Switching SDRAM to hardware control.
Memtest at 0x40000000 (2.0MiB)...
Write: 0x40000000-0x40200000 2.0MiB
Read: 0x40000000-0x40200000 2.0MiB
Memtest OK
Memspeed at 0x40000000 (Sequential, 2.0MiB)...
Write speed: 13.6MiB/s
Read speed: 15.6MiB/s
--============== Boot ==================--
Booting from serial...
Press Q or ESC to abort boot completely.
sL5DdSMmkekro
Timeout
No boot medium found
--============= Console ================--
litex>