RISCV-GDB-Paging

SV39 Paging Debug tool for GDB using python and guile

Reference: riscv-privileged-v1.10.pdf

Usage:

Place paging_debug.py or all the .scm files inside your project root.

Inside gdb console:

(gdb) so paging_debug.py

or

(gdb) so paging_debug.scm

Then you can type help paging or help v2p to show the help message.

If you have any question, please search for GDB Extension.

Note: I have no SV48 codes and emulator, so SV48.scm is not tested.

Paging Table Inspector

> (gdb) help paging
 
RISC-V SV39 MMU Paging Debugging tool.
Usage: 
    paging           : The shortcut of `paging satp` 
    paging satp      : Show page table from satp register.
    paging addr      : Show page table at addr.
Example:
    (gdb) paging
    (gdb) paging satp
    (gdb) paging 0x12340000

Virtual Address To Physical Address

(gdb) help v2p

RISC-V SV39 MMU Paging Debugging tool.
Usage: 
    v2p add          : Get Physical address of a virtual address from pagetable at satp.
    v2p pg_addr addr : Get Physical address of a virtual address from pagetable at pg_addr.
Example:
    (gdb) v2p 0x12345678
    (gdb) v2p 0x81230000 0x12345678

Example

paging:

v2p:

Todo

After finished oscomp (or a debug routine is hard for me), I may implement features list below:

1. Processes debug for custom os (flexible via user defines debug symbol, like FreeRTOS GDB).
2. Ecall tracing
3. named bitfield for register