[PATCH 20/20] Convert CONFIG_SYS_BOOTM_LEN to Kconfig

[Soeren Moch]

Hi Tom,

On 25.06.22 17:02, Tom Rini wrote:
> This converts the following to Kconfig:
>     CONFIG_SYS_BOOTM_LEN
>
> As part of this, rework error handling in boot/bootm.c so that we pass
> the buffer size to handle_decomp_error as CONFIG_SYS_BOOTM_LEN will not
> be available to host tools but we do know the size that we passed to
> malloc().
>
> Signed-off-by: Tom Rini <trini at konsulko.com>
> -- > README                                        |  6 -----
 > boot/bootm.c                                  | 24 +++++++++----------
 > cmd/Kconfig                                   | 10 ++++++++
 > configs/M5208EVBE_defconfig                   |  1 +
[...]
>   include/configs/xilinx_zynqmp_r5.h            |  1 -
>   include/configs/zynq-common.h                 |  1 -
>   scripts/config_whitelist.txt                  |  1 -
>   555 files changed, 419 insertions(+), 270 deletions(-)

Is it really necessary to create so many additional lines just for a
conversion?

>
> diff --git a/README b/README
> index fb0284d4ecb6..ff0df3797d21 100644
> --- a/README
> +++ b/README
> @@ -1736,12 +1736,6 @@ Configuration Settings:
>
>   		Non-cached memory is only supported on 32-bit ARM at present.
>
> -- CONFIG_SYS_BOOTM_LEN:
> -		Normally compressed uImages are limited to an
> -		uncompressed size of 8 MBytes. If this is not enough,
> -		you can define CONFIG_SYS_BOOTM_LEN in your board config file
> -		to adjust this setting to your needs.
> -
>   - CONFIG_SYS_BOOTMAPSZ:
>   		Maximum size of memory mapped by the startup code of
>   		the Linux kernel; all data that must be processed by
> diff --git a/boot/bootm.c b/boot/bootm.c
> index dfa65f125e57..86dbfbcfed5b 100644
> --- a/boot/bootm.c
> +++ b/boot/bootm.c
> @@ -33,11 +33,6 @@
>   #include <bootm.h>
>   #include <image.h>
>
> -#ifndef CONFIG_SYS_BOOTM_LEN
> -/* use 8MByte as default max gunzip size */
> -#define CONFIG_SYS_BOOTM_LEN	0x800000
> -#endif
> -

The old default was 8MiB, OK.

>   #define MAX_CMDLINE_SIZE	SZ_4K
>
>   #define IH_INITRD_ARCH IH_ARCH_DEFAULT
[...]
> diff --git a/cmd/Kconfig b/cmd/Kconfig
> index bb956e330750..357b82849f7f 100644
> --- a/cmd/Kconfig
> +++ b/cmd/Kconfig
> @@ -335,6 +335,16 @@ config BOOTM_VXWORKS
>   	help
>   	  Support booting VxWorks images via the bootm command.
>
> +config SYS_BOOTM_LEN
> +	hex "Maximum size of a decompresed OS image"
> +	depends on CMD_BOOTM || CMD_BOOTI || CMD_BOOTZ
> +	default 0x4000000 if PPC || ARM64
> +	default 0x1000000 if X86
> +	default 0x800000
> +	help
> +	  Normally compressed OS images are limited to an uncompressed size of
> +	  8 MiB. If this is not enough, increase this setting to fit your needs.
> +

The new default is sad to be 8MiB, too (as the old default was), but
this is not true for all architectures. So the help text is misleading.

Besides that, there is probably nothing wrong with the new defaults.

>   config CMD_BOOTEFI
>   	bool "bootefi"
>   	depends on EFI_LOADER
> diff --git a/configs/M5208EVBE_defconfig b/configs/M5208EVBE_defconfig
> index 4ab888f59ed5..858fc5bbfd2e 100644
> --- a/configs/M5208EVBE_defconfig
> +++ b/configs/M5208EVBE_defconfig
> @@ -16,6 +16,7 @@ CONFIG_SYS_MALLOC_BOOTPARAMS=y
>   # CONFIG_AUTO_COMPLETE is not set
>   CONFIG_SYS_PROMPT="-> "
>   CONFIG_SYS_PBSIZE=276
> +CONFIG_SYS_BOOTM_LEN=0x2000000
>   CONFIG_CMD_IMLS=y
>   # CONFIG_CMD_SETEXPR is not set
>   CONFIG_CMD_MII=y
[...]
> diff --git a/configs/tbs2910_defconfig b/configs/tbs2910_defconfig
> index 892d7c60d283..f0ecfd049d65 100644
> --- a/configs/tbs2910_defconfig
> +++ b/configs/tbs2910_defconfig
> @@ -35,6 +35,7 @@ CONFIG_CMD_BOOTZ=y
>   # CONFIG_BOOTM_PLAN9 is not set
>   # CONFIG_BOOTM_RTEMS is not set
>   # CONFIG_BOOTM_VXWORKS is not set
> +CONFIG_SYS_BOOTM_LEN=0x1000000

For tbs2910 there is another value set here - not the old default, not
the new one. Why?
This looks like a carefully chosen value, but very likely it is not.

Probably also this value is fine for this board, but for me it makes no
sense to set a board specific value here.

Regards,
Soeren