[PATCH v2 6/9] spacemit: k1: Add multiple device tree support

[Simon Glass]

Hi Guodong,

On Tue, 19 May 2026 at 16:49, Guodong Xu <guodong at riscstar.com> wrote:
>
> Enable multiple DTB support in the FIT image for the Spacemit K1 SoC,
> allowing a single U-Boot binary to support different board variants.
>
> The SPL reads the board type from EEPROM and selects the corresponding
> device tree at runtime via board_fit_config_name_match(), ensuring the
> correct hardware description is passed to U-Boot proper.
>
> Signed-off-by: Guodong Xu <guodong at riscstar.com>
>
> ---
> v2:
> - Reworked.  Drop the v1 approach (new local k1-muse-pi-pro.dts,
>   enlarge SYS_MALLOC_F_LEN, MMODE switch).
> - Use binman --fit-multi-config so u-boot.itb packs multiple board
>   DTs from the upstream tree.
> ---
>  board/spacemit/k1/spl.c       | 42 ++++++++++++++++++++++++++++++++++--------
>  configs/spacemit_k1_defconfig |  2 ++
>  2 files changed, 36 insertions(+), 8 deletions(-)
>
> diff --git a/board/spacemit/k1/spl.c b/board/spacemit/k1/spl.c
> index da4169fbc8c..d749e21a2d5 100644
> --- a/board/spacemit/k1/spl.c
> +++ b/board/spacemit/k1/spl.c
> @@ -13,6 +13,7 @@
>  #include <dm/device.h>
>  #include <dm/uclass.h>
>  #include <i2c.h>
> +#include <linux/ctype.h>
>  #include <linux/delay.h>
>  #include <log.h>
>  #include <power/regulator.h>
> @@ -55,6 +56,8 @@ struct ddr_cfg {
>  binman_sym_declare(ulong, ddr_fw, image_pos);
>  binman_sym_declare(ulong, ddr_fw, size);
>
> +char product_name[I2C_BUF_SIZE] = "k1";
> +
>  static void i2c_early_init(void)
>  {
>         struct udevice *bus;
> @@ -322,14 +325,8 @@ void nor_early_init(void)
>         udelay(10);
>  }
>
> -void *board_spl_fit_buffer_addr(ulong fit_size, int sectors, int bl_len)
> -{
> -       return (void *)CONFIG_SPL_LOAD_FIT_ADDRESS;
> -}
> -
>  void board_init_f(ulong dummy)
>  {
> -       u8 i2c_buf[I2C_BUF_SIZE] = { 0 };
>         int ret;
>
>         ret = spl_early_init();
> @@ -344,11 +341,11 @@ void board_init_f(ulong dummy)
>         preloader_console_init();
>
>         i2c_early_init();
> -       ret = read_product_name(i2c_buf, I2C_BUF_SIZE);
> +       ret = read_product_name(product_name, I2C_BUF_SIZE);
>         if (ret)
>                 log_info("Fail to detect board:%d\n", ret);
>         else
> -               log_info("Get board name:%s\n", (char *)i2c_buf);
> +               log_info("Get board name:%s\n", product_name);
>         pmic_init();

This is quite hacky. Firstly you should be able to delay selecting the
DT until board_init_r() - i.e. once SPL is running fully. Why is it
needed so early?

Then, you should be able to use a syscon driver to obtain the
information, using driver model. Do you have lots of size constraints
which prevent driver model in SPL?

>
>         ddr_early_init();
> @@ -363,3 +360,32 @@ u32 spl_boot_device(void)
>  void spl_board_init(void)
>  {
>  }
> +
> +int board_fit_config_name_match(const char *name)
> +{
> +       char fdt_name[I2C_BUF_SIZE];
> +       int i;
> +
> +       memset(fdt_name, 0, I2C_BUF_SIZE);
> +       if (!strncmp(product_name, "k1-x_", 5)) {
> +               snprintf(fdt_name, I2C_BUF_SIZE, "%s-%s", "k1",
> +                        &product_name[5]);
> +       }
> +       if (fdt_name[0] == '\0') {

if (!*fdt_name) {

> +               /* set default board name */
> +               sprintf(fdt_name, "k1-musepi-pro");
> +       }
> +       for (i = 0; i < I2C_BUF_SIZE; i++) {
> +               if (fdt_name[i] == '\0')

same

how about adding a helper function in lib/ to lower-case and return a string?

> +                       break;
> +               fdt_name[i] = tolower(fdt_name[i]);
> +       }
> +       if (!strcmp(name, fdt_name))
> +               return 0;

blank line before final return

> +       return -ENOENT;
> +}
> +
> +void *board_spl_fit_buffer_addr(ulong fit_size, int sectors, int bl_len)
> +{
> +       return (void *)CONFIG_SPL_LOAD_FIT_ADDRESS;
> +}
> diff --git a/configs/spacemit_k1_defconfig b/configs/spacemit_k1_defconfig
> index 64c724c62a5..465788cc2e5 100644
> --- a/configs/spacemit_k1_defconfig
> +++ b/configs/spacemit_k1_defconfig
> @@ -5,6 +5,7 @@ CONFIG_NR_DRAM_BANKS=2
>  CONFIG_HAS_CUSTOM_SYS_INIT_SP_ADDR=y
>  CONFIG_CUSTOM_SYS_INIT_SP_ADDR=0x1000000
>  CONFIG_DEFAULT_DEVICE_TREE="spacemit/k1-musepi-pro"
> +CONFIG_OF_LIST="spacemit/k1-bananapi-f3 spacemit/k1-musepi-pro"
>  CONFIG_SPL_SYS_MALLOC_F_LEN=0x4000
>  CONFIG_SPL_STACK=0xc083fb00
>  CONFIG_SPL_TEXT_BASE=0xc0801000
> @@ -27,6 +28,7 @@ CONFIG_SPL_RISCV_MMODE=y
>  # CONFIG_SPL_SMP is not set
>  CONFIG_STACK_SIZE=0x100000
>  CONFIG_FIT=y
> +CONFIG_MULTI_DTB_FIT=y
>  CONFIG_SPL_HAS_LOAD_FIT_ADDRESS=y
>  CONFIG_SPL_LOAD_FIT_ADDRESS=0x08000000
>  CONFIG_SUPPORT_RAW_INITRD=y
>
> --
> 2.43.0
>

Regards,
Simon