[PATCH RFC v3 0/7] clk: thead: Add support for TH1520 AP_SUBSYS clock controller

[Drew Fustini]

This series adds support for the AP sub-system clock controller in the
T-Head TH1520 [1]. Yangtao Li originally submitted this series in May
2023 [2]. Jisheng made additional improvements and then passed on the
work in progress to me.

Changes in RFC v3:
 - Drop redundant new line and unused clk label from the dts example in
   the DT binding which I failed to fix in v2.
 - Add patch [3] from Thomas Bonnefille that fixes dts node ordering in
   th1520.dtsi. Conor has already merged it into riscv-dt-for-next so
   the dts patches in this series are based on top of that.
 - Remove fixed uart clock and converted uart DT nodes to use clocks
   from the clock controller.
 - Remove fixed apb clock and converted the dma controller and timer DT
   nodes to use a clock from the clock controller.
 - Made ccu_disable_helper() and ccu_enable_helper() to static functions
 - Follow the advice from Stephen Boyd in Yangtao's original series to
   not use strings for clk tree topology. Created clk_parent_data arrays
   to be used with CLK_HW_INIT_PARENTS_DATA instead of parent strings.
 - Rebase on top of v6.9-rc7

Changes in RFC v2 [4]:
 - squash the header file patch into the DT schema patch
 - describe the changes I made to original series in the cover letter
   instead of the individual patches
 - fix my typo in my email address

Changes in RFC v1 [5] from the original series:
 - corrected the npu_clk enable bit
 - deduplicated CLK_NPU and CLK_NPU_AXI number in header
 - fixed c910_i0_clk reg typo
 - fixed checkpatch and dt_binding_check warnings
 - rebased on v6.9-rc5
 - revised commit descriptions

TODO:
This is still marked as an RFC because I still need to make the
improvements that Emil suggested in v1:
 - Input predivider is not handled correctly in ccu_mdiv_recalc_rate().
   The PLL multiplies the input frequency and outputs "Foutvco". This is
   followed by a post divider to produce "Foutpostdiv". However, some
   clocks derive directly from the "Foutvco". These should be modelled
   as two differnt clocks.
 - Use devm_clk_hw_register_gate() for the gates
 - Use devm_clk_hw_register_mux() for the muxes

I'll post a v1 patch once I've addressed the above issues.

Thank you,
Drew

[1] https://openbeagle.org/beaglev-ahead/beaglev-ahead/-/blob/main/docs/TH1520%20System%20User%20Manual.pdf
[2] https://lore.kernel.org/all/20230515054402.27633-1-frank.li@vivo.com/
[3] https://lore.kernel.org/all/20240425082138.374445-1-thomas.bonnefille@bootlin.com/
[4] https://lore.kernel.org/all/20240426-th1520-clk-v2-v2-0-96b829e6fcee@tenstorrent.com/
[5] https://lore.kernel.org/all/20240110-clk-th1520-v1-0-8b0682567984@tenstorrent.com/

To: Jisheng Zhang <jszhang at kernel.org>
To: Guo Ren <guoren at kernel.org>
To: Fu Wei <wefu at redhat.com>
To: Yangtao Li <frank.li at vivo.com>
To: Thomas Bonnefille <thomas.bonnefille at bootlin.com>
To: Emil Renner Berthing <emil.renner.berthing at canonical.com>
To: Michael Turquette <mturquette at baylibre.com>
To: Stephen Boyd <sboyd at kernel.org>
To: Rob Herring <robh at kernel.org>
To: Krzysztof Kozlowski <krzk+dt at kernel.org>
To: Conor Dooley <conor+dt at kernel.org>
To: Paul Walmsley <paul.walmsley at sifive.com>
To: Palmer Dabbelt <palmer at dabbelt.com>
To: Albert Ou <aou at eecs.berkeley.edu>
Cc: linux-riscv at lists.infradead.org
Cc: linux-clk at vger.kernel.org
Cc: devicetree at vger.kernel.org
Cc: linux-kernel at vger.kernel.org

Signed-off-by: Drew Fustini <dfustini at tenstorrent.com>
---
Drew Fustini (6):
      dt-bindings: clock: Document T-Head TH1520 AP_SUBSYS controller
      clk: thead: Add support for T-Head TH1520 AP_SUBSYS clocks
      riscv: dts: thead: Add TH1520 AP_SUBSYS clock controller
      riscv: dts: thead: change TH1520 uart nodes to use clock controller
      riscv: dts: thead: change TH1520 mmc nodes to use clock controller
      riscv: dts: thead: update TH1520 dma and timer nodes to use clock controller

Thomas Bonnefille (1):
      riscv: dts: thead: Fix node ordering in TH1520 device tree

 .../bindings/clock/thead,th1520-clk-ap.yaml        |   64 ++
 MAINTAINERS                                        |    3 +
 arch/riscv/boot/dts/thead/th1520-beaglev-ahead.dts |   12 -
 .../boot/dts/thead/th1520-lichee-module-4a.dtsi    |   12 -
 arch/riscv/boot/dts/thead/th1520.dtsi              |  118 ++-
 drivers/clk/Kconfig                                |    1 +
 drivers/clk/Makefile                               |    1 +
 drivers/clk/thead/Kconfig                          |   12 +
 drivers/clk/thead/Makefile                         |    2 +
 drivers/clk/thead/clk-th1520-ap.c                  | 1074 ++++++++++++++++++++
 include/dt-bindings/clock/thead,th1520-clk-ap.h    |   96 ++
 11 files changed, 1310 insertions(+), 85 deletions(-)
---
base-commit: dd5a440a31fae6e459c0d6271dddd62825505361
change-id: 20240505-th1520-clk-b8f8fb2ecf28

Best regards,
-- 
Drew Fustini <dfustini at tenstorrent.com>