[U-Boot] [PATCH 17/30] cramfs: make cramfs usable without a NOR flash

Wolfgang Denk
2011-04-30T08:20:00Z

Dear Valentin Longchamp,

In message <e0cad960c27371170bf2d2d4be3362d6665fbbfa.1302272395.git.valentin.longchamp@keymile.com> you wrote:
> From: Heiko Schocher <hs@denx.de>
>
> Signed-off-by: Heiko Schocher <hs@denx.de>
> cc: Wolfgang Denk <wd@denx.de>
> cc: Detlev Zundel <dzu@denx.de>
> cc: Valentin Longchamp <valentin.longchamp@keymile.com>
> cc: Holger Brunck <holger.brunck@keymile.com>
> Signed-off-by: Valentin Longchamp <valentin.longchamp@keymile.com>
> ---
> common/cmd_cramfs.c | 12 +++++++++++-
> fs/cramfs/cramfs.c | 4 ++++
> 2 files changed, 15 insertions(+), 1 deletions(-)
>
> diff --git a/common/cmd_cramfs.c b/common/cmd_cramfs.c
> index 8c86dc5..5e1487f 100644
> --- a/common/cmd_cramfs.c
> +++ b/common/cmd_cramfs.c
> @@ -43,7 +43,9 @@
> #endif
>
> #ifdef CONFIG_CRAMFS_CMDLINE
> -flash_info_t flash_info[1];
> +#if !defined(CONFIG_SYS_NO_FLASH)
> +#include <flash.h>
> +#endif

Do we need the #ifndef here? I don;t thik it hurts if we
unconditionally #include <flash.h> ?

But note: there was no "extern" in this declaration of flash_info[],
i. e. we _did_ allocate storage here. Is the new code really
equivalent? How extensively has it been tested?

> #ifndef CONFIG_CMD_JFFS2
> #include <linux/stat.h>
> @@ -119,7 +121,11 @@ int do_cramfs_load(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
> dev.id = &id;
> part.dev = &dev;
> /* fake the address offset */
> +#if !defined(CONFIG_SYS_NO_FLASH)
> part.offset = addr - flash_info[id.num].start[0];
> +#else
> + part.offset = addr;
> +#endif

Sequences like this repeat a number of times. How about

#ifdef CONFIG_SYS_NO_FLASH
# define OFFSET_ADJUSTMENT(x) 0
#else
# define OFFSET_ADJUSTMENT(x) (flash_info[id.num].start[x])
#endif
...
dev.id = &id;
part.dev = &dev;
/* fake the address offset */
part.offset = addr - OFFSET_ADJUSTMENT(0);

> +#if !defined(CONFIG_SYS_NO_FLASH)
> part.offset = addr - flash_info[id.num].start[0];
> +#else
> + part.offset = addr;
> +#endif

part.offset = addr - OFFSET_ADJUSTMENT(0);

> extern flash_info_t flash_info[];
> #define PART_OFFSET(x) (x->offset + flash_info[x->dev->id->num].start[0])
> +#else
> +#define PART_OFFSET(x) (x->offset)

#define PART_OFFSET(x) (x->offset + OFFSET_ADJUSTMENT(0))

[If we always refer to start[0] only, we can even omit the argument.]

Best regards,

Wolfgang Denk

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