Re: [PATCH 1/1 RFC] treewide: Deprecate OF_PRIOR_STAGE

Ilias Apalodimas
2021-09-24T13:13:39Z

Forgot to include Mark, which showed some interest for MBPs

On Fri, 24 Sept 2021 at 16:10, Ilias Apalodimas
<ilias.apalodimas@linaro.org> wrote:
>
> At some point back in 2018 prior_stage_fdt_address and OF_PRIOR_STAGE got
> introduced, in order to support a DTB handed over by an earlier stage boot
> loader. However we have another option in the Kconfig (OF_BOARD) which has
> identical semantics.
>
> A good example of this is RISC-V boards which during their startup,
> pick up the DTB from a1 and copy it in their private gd_t. Apart from that
> they also copy it to prior_stage_fdt_address, if the Kconfig option is
> selected, which seems unnecessary(??).
>
> This is mostly an RFC, trying to figure out if I am missing some subtle
> functionality, which would justify having 2 Kconfig options doing similar
> things present.
>
> - Should we do this?
> - Doesn't OF_BOARD and OF_PRIOR_STAGE practically mean "Someone else is
> going to pass me my DTB". Why should we care if that someone is a prior
> bootloader or runtime memory generated on the fly by U-Boot? It all
> boils down to having a *board* specific callback for that.
> - RISC-V binman should get rid of the option as well if we decide to go
> though with this (but I have no idea what RISC-V expects there).
> - Can we apply similar logic to OF_HOSTFILE? It seems like we could just
> have a board_fdt_blob_setup() for the sandbox that reads the file we
> want and get rid of another Kconfig option.
>
> Note that the original board which introduced CONFIG_OF_PRIOR_STAGE is still
> there. If someone cares enough I guess he could fix that as well, but I don't
> have the board around, so I prefer keeping it as is and mark the option as
> deprecated. For that board we could also keep the prior_stage_fdt_address
> without the Kconfig option and simply copy the location there, but the
> board must define it's own board_fdt_blob_setup(). That would get rid of
> the Kconfig option entirely instead of limiting it to that board only.
>
> Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
> ---
> arch/riscv/cpu/cpu.c | 3 ---
> arch/riscv/cpu/start.S | 5 -----
> board/emulation/qemu-riscv/qemu-riscv.c | 8 ++++++++
> board/sifive/unleashed/unleashed.c | 10 ++++------
> board/sifive/unmatched/unmatched.c | 10 ++++------
> configs/ae350_rv32_defconfig | 2 +-
> configs/ae350_rv32_spl_defconfig | 2 +-
> configs/ae350_rv64_defconfig | 2 +-
> configs/ae350_rv64_spl_defconfig | 2 +-
> configs/bcm7260_defconfig | 2 +-
> configs/qemu-riscv32_defconfig | 2 +-
> configs/qemu-riscv32_smode_defconfig | 2 +-
> configs/qemu-riscv32_spl_defconfig | 2 +-
> configs/qemu-riscv64_defconfig | 2 +-
> configs/qemu-riscv64_smode_defconfig | 2 +-
> configs/qemu-riscv64_spl_defconfig | 2 +-
> dts/Kconfig | 3 ++-
> lib/fdtdec.c | 4 ++++
> 18 files changed, 33 insertions(+), 32 deletions(-)
>
> diff --git a/arch/riscv/cpu/cpu.c b/arch/riscv/cpu/cpu.c
> index c894ac10b536..e16f1df30254 100644
> --- a/arch/riscv/cpu/cpu.c
> +++ b/arch/riscv/cpu/cpu.c
> @@ -16,9 +16,6 @@
> * The variables here must be stored in the data section since they are used
> * before the bss section is available.
> */
> -#ifdef CONFIG_OF_PRIOR_STAGE
> -phys_addr_t prior_stage_fdt_address __section(".data");
> -#endif
> #ifndef CONFIG_XIP
> u32 hart_lottery __section(".data") = 0;
>
> diff --git a/arch/riscv/cpu/start.S b/arch/riscv/cpu/start.S
> index 308b0a97a58f..76850ec9be2c 100644
> --- a/arch/riscv/cpu/start.S
> +++ b/arch/riscv/cpu/start.S
> @@ -142,11 +142,6 @@ call_harts_early_init:
> bnez tp, secondary_hart_loop
> #endif
>
> -#ifdef CONFIG_OF_PRIOR_STAGE
> - la t0, prior_stage_fdt_address
> - SREG s1, 0(t0)
> -#endif
> -
> jal board_init_f_init_reserve
>
> SREG s1, GD_FIRMWARE_FDT_ADDR(gp)
> diff --git a/board/emulation/qemu-riscv/qemu-riscv.c b/board/emulation/qemu-riscv/qemu-riscv.c
> index dcfd3f20bee6..7dfe471dee15 100644
> --- a/board/emulation/qemu-riscv/qemu-riscv.c
> +++ b/board/emulation/qemu-riscv/qemu-riscv.c
> @@ -14,6 +14,8 @@
> #include <virtio_types.h>
> #include <virtio.h>
>
> +DECLARE_GLOBAL_DATA_PTR;
> +
> int board_init(void)
> {
> /*
> @@ -69,3 +71,9 @@ int board_fit_config_name_match(const char *name)
> return 0;
> }
> #endif
> +void *board_fdt_blob_setup(void)
> +{
> + /* Stored the DTB address there during our init */
> + return (void *)gd->arch.firmware_fdt_addr;
> +}
> +
> diff --git a/board/sifive/unleashed/unleashed.c b/board/sifive/unleashed/unleashed.c
> index 8cd514df3005..9aa2b3e6f43a 100644
> --- a/board/sifive/unleashed/unleashed.c
> +++ b/board/sifive/unleashed/unleashed.c
> @@ -116,12 +116,10 @@ int misc_init_r(void)
>
> void *board_fdt_blob_setup(void)
> {
> - if (IS_ENABLED(CONFIG_OF_SEPARATE)) {
> - if (gd->arch.firmware_fdt_addr)
> - return (ulong *)gd->arch.firmware_fdt_addr;
> - else
> - return (ulong *)&_end;
> - }
> + if (gd->arch.firmware_fdt_addr)
> + return (ulong *)gd->arch.firmware_fdt_addr;
> + else
> + return (ulong *)&_end;
> }
>
> int board_init(void)
> diff --git a/board/sifive/unmatched/unmatched.c b/board/sifive/unmatched/unmatched.c
> index d90b252baef7..b703f9c3efc3 100644
> --- a/board/sifive/unmatched/unmatched.c
> +++ b/board/sifive/unmatched/unmatched.c
> @@ -13,12 +13,10 @@
>
> void *board_fdt_blob_setup(void)
> {
> - if (IS_ENABLED(CONFIG_OF_SEPARATE)) {
> - if (gd->arch.firmware_fdt_addr)
> - return (ulong *)gd->arch.firmware_fdt_addr;
> - else
> - return (ulong *)&_end;
> - }
> + if (gd->arch.firmware_fdt_addr)
> + return (ulong *)gd->arch.firmware_fdt_addr;
> + else
> + return (ulong *)&_end;
> }
>
> int board_init(void)
> diff --git a/configs/ae350_rv32_defconfig b/configs/ae350_rv32_defconfig
> index 4e7a1686a64d..8b6c0b8a4a0a 100644
> --- a/configs/ae350_rv32_defconfig
> +++ b/configs/ae350_rv32_defconfig
> @@ -15,7 +15,7 @@ CONFIG_CMD_SF_TEST=y
> # CONFIG_CMD_SETEXPR is not set
> CONFIG_BOOTP_PREFER_SERVERIP=y
> CONFIG_CMD_CACHE=y
> -CONFIG_OF_PRIOR_STAGE=y
> +CONFIG_OF_BOARD=y
> CONFIG_ENV_OVERWRITE=y
> CONFIG_ENV_IS_IN_SPI_FLASH=y
> CONFIG_SYS_RELOC_GD_ENV_ADDR=y
> diff --git a/configs/ae350_rv32_spl_defconfig b/configs/ae350_rv32_spl_defconfig
> index 34c6af6e7e17..a0fe9b9a71df 100644
> --- a/configs/ae350_rv32_spl_defconfig
> +++ b/configs/ae350_rv32_spl_defconfig
> @@ -19,7 +19,7 @@ CONFIG_CMD_SF_TEST=y
> # CONFIG_CMD_SETEXPR is not set
> CONFIG_BOOTP_PREFER_SERVERIP=y
> CONFIG_CMD_CACHE=y
> -CONFIG_OF_PRIOR_STAGE=y
> +CONFIG_OF_BOARD=y
> CONFIG_ENV_OVERWRITE=y
> CONFIG_ENV_IS_IN_SPI_FLASH=y
> CONFIG_BOOTP_SEND_HOSTNAME=y
> diff --git a/configs/ae350_rv64_defconfig b/configs/ae350_rv64_defconfig
> index 05eee371ac2f..b12a8810a221 100644
> --- a/configs/ae350_rv64_defconfig
> +++ b/configs/ae350_rv64_defconfig
> @@ -16,7 +16,7 @@ CONFIG_CMD_SF_TEST=y
> # CONFIG_CMD_SETEXPR is not set
> CONFIG_BOOTP_PREFER_SERVERIP=y
> CONFIG_CMD_CACHE=y
> -CONFIG_OF_PRIOR_STAGE=y
> +CONFIG_OF_board=y
> CONFIG_ENV_OVERWRITE=y
> CONFIG_ENV_IS_IN_SPI_FLASH=y
> CONFIG_SYS_RELOC_GD_ENV_ADDR=y
> diff --git a/configs/ae350_rv64_spl_defconfig b/configs/ae350_rv64_spl_defconfig
> index 9cd7848c92eb..9ad312505db3 100644
> --- a/configs/ae350_rv64_spl_defconfig
> +++ b/configs/ae350_rv64_spl_defconfig
> @@ -20,7 +20,7 @@ CONFIG_CMD_SF_TEST=y
> # CONFIG_CMD_SETEXPR is not set
> CONFIG_BOOTP_PREFER_SERVERIP=y
> CONFIG_CMD_CACHE=y
> -CONFIG_OF_PRIOR_STAGE=y
> +CONFIG_OF_BOARD=y
> CONFIG_ENV_OVERWRITE=y
> CONFIG_ENV_IS_IN_SPI_FLASH=y
> CONFIG_BOOTP_SEND_HOSTNAME=y
> diff --git a/configs/bcm7260_defconfig b/configs/bcm7260_defconfig
> index a42a6acb06d5..be0c945dc811 100644
> --- a/configs/bcm7260_defconfig
> +++ b/configs/bcm7260_defconfig
> @@ -22,7 +22,7 @@ CONFIG_CMD_CACHE=y
> CONFIG_CMD_EXT2=y
> CONFIG_CMD_EXT4=y
> CONFIG_CMD_FS_GENERIC=y
> -CONFIG_OF_PRIOR_STAGE=y
> +CONFIG_OF_BOARD=y
> CONFIG_ENV_OVERWRITE=y
> CONFIG_ENV_IS_IN_MMC=y
> CONFIG_SYS_REDUNDAND_ENVIRONMENT=y
> diff --git a/configs/qemu-riscv32_defconfig b/configs/qemu-riscv32_defconfig
> index 8ac16cf4186e..6fe133c268d7 100644
> --- a/configs/qemu-riscv32_defconfig
> +++ b/configs/qemu-riscv32_defconfig
> @@ -9,6 +9,6 @@ CONFIG_DISPLAY_BOARDINFO=y
> CONFIG_CMD_BOOTEFI_SELFTEST=y
> CONFIG_CMD_NVEDIT_EFI=y
> # CONFIG_CMD_MII is not set
> -CONFIG_OF_PRIOR_STAGE=y
> +CONFIG_OF_BOARD=y
> CONFIG_SYS_RELOC_GD_ENV_ADDR=y
> CONFIG_DM_MTD=y
> diff --git a/configs/qemu-riscv32_smode_defconfig b/configs/qemu-riscv32_smode_defconfig
> index 05eda439618f..c67e8206d1ab 100644
> --- a/configs/qemu-riscv32_smode_defconfig
> +++ b/configs/qemu-riscv32_smode_defconfig
> @@ -10,6 +10,6 @@ CONFIG_DISPLAY_BOARDINFO=y
> CONFIG_CMD_BOOTEFI_SELFTEST=y
> CONFIG_CMD_NVEDIT_EFI=y
> # CONFIG_CMD_MII is not set
> -CONFIG_OF_PRIOR_STAGE=y
> +CONFIG_OF_BOARD=y
> CONFIG_SYS_RELOC_GD_ENV_ADDR=y
> CONFIG_DM_MTD=y
> diff --git a/configs/qemu-riscv32_spl_defconfig b/configs/qemu-riscv32_spl_defconfig
> index ee81e552724d..77e81fac3af7 100644
> --- a/configs/qemu-riscv32_spl_defconfig
> +++ b/configs/qemu-riscv32_spl_defconfig
> @@ -12,6 +12,6 @@ CONFIG_DISPLAY_CPUINFO=y
> CONFIG_DISPLAY_BOARDINFO=y
> CONFIG_CMD_SBI=y
> # CONFIG_CMD_MII is not set
> -CONFIG_OF_PRIOR_STAGE=y
> +CONFIG_OF_BOARD=y
> CONFIG_SYS_RELOC_GD_ENV_ADDR=y
> CONFIG_DM_MTD=y
> diff --git a/configs/qemu-riscv64_defconfig b/configs/qemu-riscv64_defconfig
> index daf5d655d01f..90e87672aab0 100644
> --- a/configs/qemu-riscv64_defconfig
> +++ b/configs/qemu-riscv64_defconfig
> @@ -10,6 +10,6 @@ CONFIG_DISPLAY_BOARDINFO=y
> CONFIG_CMD_BOOTEFI_SELFTEST=y
> CONFIG_CMD_NVEDIT_EFI=y
> # CONFIG_CMD_MII is not set
> -CONFIG_OF_PRIOR_STAGE=y
> +CONFIG_OF_BOARD=y
> CONFIG_SYS_RELOC_GD_ENV_ADDR=y
> CONFIG_DM_MTD=y
> diff --git a/configs/qemu-riscv64_smode_defconfig b/configs/qemu-riscv64_smode_defconfig
> index 4a6416e2540b..0a8393903368 100644
> --- a/configs/qemu-riscv64_smode_defconfig
> +++ b/configs/qemu-riscv64_smode_defconfig
> @@ -13,6 +13,6 @@ CONFIG_DISPLAY_BOARDINFO=y
> CONFIG_CMD_BOOTEFI_SELFTEST=y
> CONFIG_CMD_NVEDIT_EFI=y
> # CONFIG_CMD_MII is not set
> -CONFIG_OF_PRIOR_STAGE=y
> +CONFIG_OF_BOARD=y
> CONFIG_SYS_RELOC_GD_ENV_ADDR=y
> CONFIG_DM_MTD=y
> diff --git a/configs/qemu-riscv64_spl_defconfig b/configs/qemu-riscv64_spl_defconfig
> index 429d4d814e65..a15e82dd3ee1 100644
> --- a/configs/qemu-riscv64_spl_defconfig
> +++ b/configs/qemu-riscv64_spl_defconfig
> @@ -13,6 +13,6 @@ CONFIG_DISPLAY_CPUINFO=y
> CONFIG_DISPLAY_BOARDINFO=y
> CONFIG_CMD_SBI=y
> # CONFIG_CMD_MII is not set
> -CONFIG_OF_PRIOR_STAGE=y
> +CONFIG_OF_BOARD=y
> CONFIG_SYS_RELOC_GD_ENV_ADDR=y
> CONFIG_DM_MTD=y
> diff --git a/dts/Kconfig b/dts/Kconfig
> index dabe0080c1ef..2c5b2ec2d1f8 100644
> --- a/dts/Kconfig
> +++ b/dts/Kconfig
> @@ -107,7 +107,7 @@ config OF_EMBED
> Boards in the mainline U-Boot tree should not use it.
>
> config OF_BOARD
> - bool "Provided by the board at runtime"
> + bool "Provided by the board (e.g a previous loader) at runtime"
> depends on !SANDBOX
> help
> If this option is enabled, the device tree will be provided by
> @@ -124,6 +124,7 @@ config OF_HOSTFILE
>
> config OF_PRIOR_STAGE
> bool "Prior stage bootloader DTB for DT control"
> + depends on ARCH_BCMSTB
> help
> If this option is enabled, the device tree used for DT
> control will be read from a device tree binary, at a memory
> diff --git a/lib/fdtdec.c b/lib/fdtdec.c
> index 7358cb6dd168..8d0db5ac6173 100644
> --- a/lib/fdtdec.c
> +++ b/lib/fdtdec.c
> @@ -1581,6 +1581,10 @@ int fdtdec_setup(void)
> return -1;
> }
> # elif defined(CONFIG_OF_PRIOR_STAGE)
> + /*
> + * obsolete don't use this on newer boards. Prefer CONFIG_OF_BOARD
> + * instead
> + */
> gd->fdt_blob = (void *)(uintptr_t)prior_stage_fdt_address;
> # endif
> # ifndef CONFIG_SPL_BUILD
> --
> 2.33.0
>