Fix test10. It broke while implementing interrupt based syscalls.
Cleaning up after the previous test. We reset the memory bus to a known
idle state. We also reset the DUT to make the SPI master visible.
Fix test1. It broke while implementing interrupt based syscalls.
Instead of writing to ADDR_SYSTEM_MODE_CTRL, app mode is now entered
automatically when executing outside of ROM.
Fix test1. It broke while implementing interrupt based syscalls.
Instead of writing to ADDR_SYSTEM_MODE_CTRL, app mode is now entered
automatically when executing outside of ROM.
After the first time system_mode is set to one, the assets will no
longer be read- or writeable, even if system_mode is set to zero at a
later syscall. This is to make sure syscalls does not have the same
privilege as the firmware has at first boot.
We need to monitor when system_mode is set to one, otherwise we might
accedentially lock the assets before actually leaving firmware, for
example if firmware would use a function set in any of the registers
used in system_mode_ctrl.
Co-authored-by: Mikael Ågren <mikael@tillitis.se>
App is embedded in firmware and is loaded into app RAM when firmware
starts.
App continuously calls SET_LED syscalls.
Simulation: `make tb_application_fpga_irqpoc_c_example`
Allow FW RAM access only in the following execution contexts:
- Firmware mode
- IRQ_SYSCALL_HI
Input port `system_mode` of the `fw_ram` module is replaced with an
enable port. Since access to FW RAM not longer depend only on
system_mode
Adds a basic example firmware that copies an app to app RAM. The app
triggers syscall interrupts and tries to execute ROM code from app mode.
A make target (`tb_application_fpga_irqpoc_with_app`) that simulates a
Tkey running the firmware is added.
Only allow executing from ROM when in one of the following execution
contexts:
- Firmware mode
- IRQ_SYSCALL_LO
- IRQ_SYSCALL_HI
Co-authored-by: Daniel Jobson <jobson@tillitis.se>
Instead of manually switching to app mode using the system mode
register, app mode will be enabled when executing outside of firmware
ROM.
Co-authored-by: Mikael Ågren <mikael@tillitis.se>
A proof-of-concept of enabling PicoRV32 interrupts. Two interrupt
sources, which can be triggered by writes to memory addresses, are
added. The design has only been simulated, not run on hardware.
Synthesis:
Ice40 LC utilization is 93% (4934/5280) when built using tkey-builder:4
Simulation:
A `tb_application_fpga_irqpoc` target is added. Running `make
tb_application_fpga_irqpoc` creates `tb_application_fpga_sim.fst` which
can be inspected in GTKWave or Surfer.
Firmware:
A simple firmware is added in `fw/irqpoc`. It enables both interrupts
and triggers each interrupt once.
Custom PicoRV32 instructions are located in `custom_ops.S`. It is
imported from upstream PicoRV32 commit:
70f3c33ac8
For ages we have had a comment saying:
For Verilator 5.019 -Wno-GENUNNAMED needs to be added to LINT_FLAGS for the
cell library.
With the new tkey-builder we have 5.028, so it's time to apply this flag.
Fix CDC configuration problem on Windows when we have a composite
device (multiple different Device Classes). Add "Interface Association
Descriptor" to make it work.
Fix off-by-one UART bitrate counter value that will make the RX
sampling and TX sending drift. The impact gets higher as the baudrate
increases and the bitrate counter value gets smaller.
Reconfigure the baudrate to keep 500 kbaud.
Correct a forgotten test in testfw that wasn't updated the last time
frequency was raised in commit
75b028505f0d6dc685d37b84d73ddb9db5ee7ea2 in June 17, 2024.
- Use CTS signals to let the FPGA and CH552 signal each other that
it is OK send UART data.
- Update the CH552 rx and frame handling logic.
- Fix minor spelling errors and indentation
Add incoming and outgoing CTS (Clear To Send) signals for the FPGA to
let the CH552 and FPGA signal each other that it is OK to send UART
data. The CTS signals indicate "OK to send" if high. If an incoming
CTS signal goes low, the receiver of that signal should immediatly
stop sending UART data.
Throwing away mode and length from incoming data. Adding mode and
length to outgoing data.
Splitting responses into frames small enough for the USB<->UART
transceiver to handle.
- Add USB HID support.
- Introduce a small protocol to distinguish between CDC and HID data
sent over the UART.
- Add some debug printing.
- Cleanup of code and formatting.
- Extend hardware checks for invalid memory accesses to include
checking more address space.
- In fw include file: fix two typos for memory ranges that relates to
above that fortunately have no impact on functionality.
synth.json shouldn't depend on uds.hex and udi.hex because that
triggers a complete rebuild of the bitstream if the UDI or UDS are
changed.
Instead, we want only the application_fpga.asc to depend on them, so
we can patch in the UDS and UDI with tools/patch_uds_udi.py in an
existing application_fpga_par.json.
