Re: [PATCH v7 0/5] riscv: Add Ssqosid and initial CBQRI resctrl support
From: Chen Pei
Date: Wed Sep 02 2026 - 23:38:37 EST
> This series adds initial RISC-V QoS support: the Ssqosid extension [1]
> (srmcfg CSR), the CBQRI controller interface [2] integrated with resctrl
> [3], and a DT-based platform driver for cache controllers. It has been
> tested on both the Tenstorrent Ascalon Shared Cache controller and a QEMU
> implementation [4].
Hi Drew,
I picked up this series for testing as promised. I exercised it on both
QEMU (using the riscv.cbqri.capacity device from your branch [4]) and on
real FPGA hardware with a CBQRI capacity controller, and behavior and
functionality look good on both.
What I verified:
- Mounting resctrl and reading the default schemata (CBM reflects the
controller's capacity blocks).
- Creating control groups, writing a narrower CBM to schemata and reading
it back; the value matches what was written.
- Assigning tasks to control groups, with the RCID taking effect via
srmcfg on schedule-in.
- The CBQRI capacity-controller block-mask limit actually constraining
cache capacity allocation.
No functional issues observed.
For full disclosure, this was a general functional pass over the main
resctrl operations to confirm the controls take effect, rather than
exhaustive or corner-case testing.
Tested-by: Chen Pei <cp0613@xxxxxxxxxxxxxxxxx>
Best regards,
Pei