Am Sonntag, 1. November 2026, 09:22:53 Mitteleuropäische Normalzeit schrieb Jiaxing Hu: > From: Igor Paunovic <[email protected]> > > rocket_core_init() hands core->clks to devm_clk_bulk_get() without ever > setting the .id members. The rocket_core array is allocated with > devm_kcalloc() in rocket_device_init(), and rocket_probe() only fills in > .rdev, .dev and .index, so all four clk_bulk_data entries are requested > with a NULL con_id (unlike core->resets, whose ids are set a few lines > above). > > clk_get(dev, NULL) ends up in of_clk_get_hw(np, 0, NULL), and > of_parse_clkspec() only consults "clock-names" when a name was passed, so > the index stays 0 for all four entries. Every entry therefore ends up > holding a handle to the *first* clock of the DT "clocks" property, i.e. > ACLK_NPUn. Nothing fails: probe succeeds and the driver believes it owns > four different clocks. > > The consequence is that rocket_device_runtime_resume() prepares and enables > the AXI clock four times, while hclk, pclk and - most importantly - the NPU > compute clock ("npu", SCMI_CLK_NPU on RK3588) are never prepared or enabled > by this driver at all. The NPU still works only because the Rockchip > power-domain driver sets GENPD_FLAG_PM_CLK and its attach_dev() callback > walks the device node with of_clk_get() and adds every clock to the pm_clk > list, so genpd happens to keep the remaining clocks running. The bug is > therefore latent today, but it means the driver holds no reference to the > clock that actually feeds the NPU, which stands in the way of any future > frequency scaling (OPP/devfreq) work. > > Found on an Orange Pi 5 Plus (RK3588) by reading the live clock tree: > /sys/kernel/debug/clk/clk_summary shows four "fdab0000.npu" consumer > handles on aclk_npu0 (and likewise on aclk_npu1/aclk_npu2 for the other two > cores), while hclk_npu0, pclk_npu_root and scmi_clk_npu have no > "fdab0000.npu" consumer at all - their only consumers are the > "npu@fdab0000" handles created by the power-domain driver via of_clk_get(). > > Set the ids explicitly, in the order mandated by the binding > (Documentation/devicetree/bindings/npu/rockchip,rk3588-rknn-core.yaml): > aclk, hclk, npu, pclk. After the change the driver holds one handle per > distinct clock and clk_bulk_prepare_enable() covers all four. > > Note that this is a user-visible tightening for out-of-tree DTs: the old > NULL-id requests resolved by index and succeeded no matter what > "clock-names" contained, while the named requests fail probe with -ENOENT > when one of the four names is missing. That is the right outcome for > in-tree users - the binding requires exactly these four clock-names and > rk3588-base.dtsi carries them on all three cores - but a DT that relied on > the permissive lookup goes from silently running on the wrong clock handles > to not probing at all, so record the change here where git log will find > it. > > Fixes: ed98261b4168 ("accel/rocket: Add a new driver for Rockchip's NPU") > Signed-off-by: Igor Paunovic <[email protected]> > Tested-by: Sidong Yang <[email protected]> > Tested-by: Diederik de Haas <[email protected]> # NanoPC-T6 LTS, > NanoPC-T6 Plus > Reviewed-by: Sebastian Reichel <[email protected]> > Reviewed-by: Jiaxing Hu <[email protected]> > Signed-off-by: Jiaxing Hu <[email protected]>
Reviewed-by: Heiko Stuebner <[email protected]> nit: the commit description could be way shorter, for that small change.
