[U-Boot] [PATCH v2] nios2: reset cfi flash before reading env

[Scott McNutt <smcnutt@psyent.com>]

Applied to:

  git://git.denx.de/u-boot-nios next

Thanks,
--Scott

Thomas Chou wrote:
> Flash might be in unknown state when u-boot is started with jtag.
> And got wrong env data. So reset it in board early init.
> 
> We cannot use generic cfi flash routines, because flash_init() is
> not run yet.
> 
> Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
> ---
> v2 use weak func to reset flash, as Wolfgang suggested.
>    reset the chip where env is located.
> 
>  board/altera/nios2-generic/nios2-generic.c |   16 ++++++++++++++++
>  1 files changed, 16 insertions(+), 0 deletions(-)
> 
> diff --git a/board/altera/nios2-generic/nios2-generic.c b/board/altera/nios2-generic/nios2-generic.c
> index 89848cf..220a4c4 100644
> --- a/board/altera/nios2-generic/nios2-generic.c
> +++ b/board/altera/nios2-generic/nios2-generic.c
> @@ -24,12 +24,28 @@
>  
>  #include <common.h>
>  #include <netdev.h>
> +#include <mtd/cfi_flash.h>
> +#include <asm/io.h>
>  
>  void text_base_hook(void); /* nop hook for text_base.S */
>  
> +#if defined(CONFIG_ENV_IS_IN_FLASH) && defined(CONFIG_ENV_ADDR)
> +static void __early_flash_cmd_reset(void)
> +{
> +	/* reset flash before we read env */
> +	writeb(AMD_CMD_RESET, CONFIG_ENV_ADDR);
> +	writeb(FLASH_CMD_RESET, CONFIG_ENV_ADDR);
> +}
> +void early_flash_cmd_reset(void)
> +	__attribute__((weak,alias("__early_flash_cmd_reset")));
> +#endif
> +
>  int board_early_init_f(void)
>  {
>  	text_base_hook();
> +#if defined(CONFIG_ENV_IS_IN_FLASH) && defined(CONFIG_ENV_ADDR)
> +	early_flash_cmd_reset();
> +#endif
>  	return 0;
>  }
>