[PATCH 1/1 RFC] treewide: Deprecate OF_PRIOR_STAGE

Ilias Apalodimas
2021-09-24T13:10:36Z

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