[U-Boot] [PATCH 4/5] cfi_flash: handle 'chip size exceeds address window' situation

[Stefan Roese <sr@denx.de>]

Hi Ilya,

On Thursday 21 October 2010 17:20:12 Ilya Yanok wrote:
> On some boards we have flash mapped high in the address space with
> considerably small window (say 0xFE000000 and 32MB). When we install
> bigger chip (say 64MB) on such a board strange things happen
> (flash_write() doesn't work at all, for ex). That's because cfi_flash
> driver doesn't care about window size at all.
> Of course, cleanest solution would probably be to just extend address
> window to be able to map the whole flash but for legacy/compatibility
> reasons some people prefer just truncate the flash size and never use
> the upper part.
> This patch adds an option for cfi_flash driver to handle this situation
> properly. To achieve this we add the new function cfi_flash_bank_size()
> which can be provided by the board code and weak-aliased to default
> implementation that returns value from the CONFIG_SYS_FLASH_BANKS_SIZES
> array if it's defined or 0 otherwise (the last case is added for
> compatibility).
> If non-zero flash bank size is provided and detected chip size is bigger
> than provided address window size the warning will be displayed and
> flash chip will be truncated.
> 
> Signed-off-by: Ilya Yanok <yanok@emcraft.com>
> ---
>  drivers/mtd/cfi_flash.c |   28 +++++++++++++++++++++++-----
>  1 files changed, 23 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/mtd/cfi_flash.c b/drivers/mtd/cfi_flash.c
> index 798902f..c444b53 100644
> --- a/drivers/mtd/cfi_flash.c
> +++ b/drivers/mtd/cfi_flash.c
> @@ -85,6 +85,17 @@ static phys_addr_t __cfi_flash_bank_addr(int i)
>  phys_addr_t cfi_flash_bank_addr(int i)
>  	__attribute__((weak, alias("__cfi_flash_bank_addr")));
> 
> +static phys_addr_t __cfi_flash_bank_size(int i)
> +{
> +#ifdef CONFIG_SYS_FLASH_BANKS_SIZES
> +	return ((unsigned long [])CONFIG_SYS_FLASH_BANKS_SIZES)[i];
> +#else
> +	return 0;
> +#endif
> +}
> +phys_addr_t cfi_flash_bank_size(int i)
> +	__attribute__((weak, alias("__cfi_flash_bank_size")));

Please use a consistent type here (phys_addr_t vs. unsigned long). unsigned 
long seems to be the correct one looking at the caller function.

Otherwise:

Acked-by: Stefan Roese <sr@denx.de>

Wolfgang, feel free to pull this directly if you like.

Cheers,
Stefan

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