[U-Boot] [PATCH 1/2] flash/cfi_flash: Use virtual sector start address, not phys

Pieter phenning at vastech.co.za
Tue Feb 3 09:53:12 CET 2009


Becky Bruce wrote:
> include/flash.h was commented to say that the address in
> flash_info->start was a physical address.  However, from u-boot's
> point of view, and looking at most flash code, it makes more
> sense for this to be a virtual address.  So I corrected the
> comment to indicate that this was a virtual address.
>
> The only flash driver that was actually treating the address
> as physical was the mtd/cfi_flash driver.  However, this code
> was using it inconsistently as it actually directly dereferenced
> the "start" element, while it used map_physmem to get a
> virtual address in other places.  I changed this driver so
> that the code which initializes the info->start field calls
> map_physmem to get a virtual address, eliminating the need for
> further map_physmem calls.  The code is now consistent.
>
> The *only* place a physical address should be used is when defining the
> flash banks list that is used to initialize the flash_info struct,
> usually found in the board config file.
>
> Signed-off-by: Becky Bruce <beckyb at kernel.crashing.org>
> ---
>  drivers/mtd/cfi_flash.c |   53 +++++++++++++++++++++-------------------------
>  include/flash.h         |    2 +-
>  2 files changed, 25 insertions(+), 30 deletions(-)
>
> diff --git a/drivers/mtd/cfi_flash.c b/drivers/mtd/cfi_flash.c
> index 84ff7e8..4cb5fb5 100644
> --- a/drivers/mtd/cfi_flash.c
> +++ b/drivers/mtd/cfi_flash.c
> @@ -305,17 +305,12 @@ flash_map (flash_info_t * info, flash_sect_t sect, uint offset)
>  {
>  	unsigned int byte_offset = offset * info->portwidth;
>  
> -	return map_physmem(info->start[sect] + byte_offset,
> -			flash_sector_size(info, sect) - byte_offset,
> -			MAP_NOCACHE);
> +	return (void *)(info->start[sect] + byte_offset);
>  }
>  
>  static inline void flash_unmap(flash_info_t *info, flash_sect_t sect,
>  		unsigned int offset, void *addr)
>  {
> -	unsigned int byte_offset = offset * info->portwidth;
> -
> -	unmap_physmem(addr, flash_sector_size(info, sect) - byte_offset);
>  }
<snip>

Since "flash_unmap(flash_info_t *info, flash_sect_t sect,unsigned int offset, void *addr)" function is empty after applying the patch, should all function calls in the /drivers/mtd/cfi_flash.c file not also be removed?

cheers pieter




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