[PATCH 00/10] Initial SPL support for T-Head TH1520 SoC

[Yao Zi]

This series adds initial SPL support for T-Head TH1520 SoC and Sipeed
Lichee Pi 4A board. Key changes include,

- Support for T-Head-specific cache management operations is split out
  of CV1800B port and adapted for usage in other ports.
- A new CPU target, THEAD_TH1520, is added with SPL support enabled.
- Driver for TH1520's DDR controller is cleaned up from the vendor
  U-Boot source.
- For building the bootable image, of which TH1520's BROM executes from
  the start, from SPL, DDR firmware and proper U-Boot, a binman
  configuration for TH1520 is added.

Note that the binman configuration doesn't inherit the default one for
RISC-V, as our proper U-Boot runs in M-Mode and reusing
riscv/dts/binman.dtsi doesn't help much.

Tested on the 16GiB variant of Sipeed Lichee Pi 4A. Loading
u-boot-with-spl.bin to SRAM with fastboot through BROM, I've
successfully booted into U-Boot console with DRAM initialized.

This series is based on the latest master branch. Additionally, the DDR
driver depends on series "Fix binman_sym functionality on RISC-V
port"[1] that has been merged earlier today to obtain the firmware.

Thanks for your time and review.

[1]: https://lore.kernel.org/all/20250416162533.1396-1-ziyao@disroot.org/

Yao Zi (10):
  riscv: lib: Split out support for T-Head cache management operations
  riscv: dts: th1520: Add clock-frequency for UART0
  riscv: cpu: Add TH1520 CPU support
  ram: thead: Add initial DDR controller support for TH1520
  riscv: dts: th1520: Preserve necessary devices for SPL
  riscv: dts: lichee-module-4a: Preserve memory node for SPL
  riscv: dts: th1520: Add DRAM controller
  riscv: dts: th1520: Add binman configuration
  board: thead: licheepi4a: Enable SPL support
  doc: thead: lpi4a: Update documentation

 arch/riscv/Kconfig                            |   9 +
 arch/riscv/cpu/cv1800b/Kconfig                |   1 +
 arch/riscv/cpu/cv1800b/Makefile               |   1 -
 arch/riscv/cpu/th1520/Kconfig                 |  21 +
 arch/riscv/cpu/th1520/Makefile                |   8 +
 arch/riscv/cpu/th1520/cache.c                 |  32 +
 arch/riscv/cpu/th1520/cpu.c                   |  21 +
 arch/riscv/cpu/th1520/dram.c                  |  21 +
 arch/riscv/cpu/th1520/spl.c                   |  31 +
 arch/riscv/dts/th1520-lichee-module-4a.dtsi   |   1 +
 arch/riscv/dts/th1520-lichee-pi-4a.dts        |   1 +
 arch/riscv/dts/th1520.dtsi                    |  17 +
 arch/riscv/dts/thead-th1520-binman.dtsi       |  55 ++
 arch/riscv/include/asm/arch-th1520/cpu.h      |   9 +
 arch/riscv/include/asm/arch-th1520/spl.h      |  10 +
 arch/riscv/lib/Makefile                       |   1 +
 .../{cpu/cv1800b/cache.c => lib/thead_cmo.c}  |   0
 board/thead/th1520_lpi4a/Kconfig              |   5 +-
 board/thead/th1520_lpi4a/Makefile             |   1 +
 board/thead/th1520_lpi4a/spl.c                |  48 ++
 configs/th1520_lpi4a_defconfig                |  18 +
 doc/board/thead/lpi4a.rst                     |  58 +-
 drivers/ram/Kconfig                           |   1 +
 drivers/ram/Makefile                          |   4 +
 drivers/ram/thead/Kconfig                     |   5 +
 drivers/ram/thead/Makefile                    |   1 +
 drivers/ram/thead/th1520_ddr.c                | 781 ++++++++++++++++++
 27 files changed, 1155 insertions(+), 6 deletions(-)
 create mode 100644 arch/riscv/cpu/th1520/Kconfig
 create mode 100644 arch/riscv/cpu/th1520/Makefile
 create mode 100644 arch/riscv/cpu/th1520/cache.c
 create mode 100644 arch/riscv/cpu/th1520/cpu.c
 create mode 100644 arch/riscv/cpu/th1520/dram.c
 create mode 100644 arch/riscv/cpu/th1520/spl.c
 create mode 100644 arch/riscv/dts/thead-th1520-binman.dtsi
 create mode 100644 arch/riscv/include/asm/arch-th1520/cpu.h
 create mode 100644 arch/riscv/include/asm/arch-th1520/spl.h
 rename arch/riscv/{cpu/cv1800b/cache.c => lib/thead_cmo.c} (100%)
 create mode 100644 board/thead/th1520_lpi4a/spl.c
 create mode 100644 drivers/ram/thead/Kconfig
 create mode 100644 drivers/ram/thead/Makefile
 create mode 100644 drivers/ram/thead/th1520_ddr.c

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2.49.0