This is a subset of a larger patch series enabling the Imagination BXM-4-64 GPU on the LicheePi 4A board, which is powered by the T-HEAD TH1520 SoC. While the full series includes power-domain, reset, and firmware changes, this part focuses solely on the clock subsystem needed for the GPU and other VO (video output) blocks. By merging these clock patches independently, we prepare the groundwork for future GPU integration via the `drm/imagination` driver. The T-HEAD TH1520 SoC features multiple clock controllers. Initially, only the AP clock controller was supported upstream. The patches below add support for the VO (video output) clock controller, which manages GPU-related gates, HDMI, and other multimedia clocks. Additionally, they introduce a mechanism to provide no-op operations for the GPU's "mem" clock gate (documented as “Reserved” in the hardware manual) and coordinate the GPU CLKGEN reset in the clock driver. Bigger series cover letter: https://lore.kernel.org/all/20250219140239.1378758-1-m.wilczynski@xxxxxxxxxxx/ Michal Wilczynski (4): dt-bindings: clock: thead: Add TH1520 VO clock controller clk: thead: Add clock support for VO subsystem in T-Head TH1520 SoC clk: thead: Add support for custom ops in CCU_GATE_CLK_OPS macro clk: thead: Add GPU clock gate control with CLKGEN reset support .../bindings/clock/thead,th1520-clk-ap.yaml | 33 +- drivers/clk/thead/clk-th1520-ap.c | 298 ++++++++++++++++-- .../dt-bindings/clock/thead,th1520-clk-ap.h | 34 ++ 3 files changed, 334 insertions(+), 31 deletions(-) -- 2.34.1
