[U-Boot] [PATCH v2 4/5] at91: 9x5: change SMC config timing that both works for PMECC & non-PMECC.

Andreas Bießmann andreas.devel at googlemail.com
Tue Aug 21 12:46:21 CEST 2012


Dear Josh Wu,

On 16.08.2012 07:05, Josh Wu wrote:
> Signed-off-by: Josh Wu <josh.wu at atmel.com>
> ---
>  board/atmel/at91sam9x5ek/at91sam9x5ek.c |   12 ++++++------
>  1 file changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/board/atmel/at91sam9x5ek/at91sam9x5ek.c b/board/atmel/at91sam9x5ek/at91sam9x5ek.c
> index 17db0fd..8dc24ab 100644
> --- a/board/atmel/at91sam9x5ek/at91sam9x5ek.c
> +++ b/board/atmel/at91sam9x5ek/at91sam9x5ek.c
> @@ -63,13 +63,13 @@ static void at91sam9x5ek_nand_hw_init(void)
>  	writel(csa, &matrix->ebicsa);
>  
>  	/* Configure SMC CS3 for NAND/SmartMedia */
> -	writel(AT91_SMC_SETUP_NWE(2) | AT91_SMC_SETUP_NCS_WR(0) |
> -		AT91_SMC_SETUP_NRD(2) | AT91_SMC_SETUP_NCS_RD(0),
> +	writel(AT91_SMC_SETUP_NWE(1) | AT91_SMC_SETUP_NCS_WR(0) |
> +		AT91_SMC_SETUP_NRD(1) | AT91_SMC_SETUP_NCS_RD(0),
>  		&smc->cs[3].setup);
> -	writel(AT91_SMC_PULSE_NWE(4) | AT91_SMC_PULSE_NCS_WR(4) |
> -		AT91_SMC_PULSE_NRD(4) | AT91_SMC_PULSE_NCS_RD(4),
> +	writel(AT91_SMC_PULSE_NWE(3) | AT91_SMC_PULSE_NCS_WR(5) |
> +		AT91_SMC_PULSE_NRD(4) | AT91_SMC_PULSE_NCS_RD(6),
>  		&smc->cs[3].pulse);
> -	writel(AT91_SMC_CYCLE_NWE(7) | AT91_SMC_CYCLE_NRD(7),
> +	writel(AT91_SMC_CYCLE_NWE(5) | AT91_SMC_CYCLE_NRD(6),
>  		&smc->cs[3].cycle);
>  	writel(AT91_SMC_MODE_RM_NRD | AT91_SMC_MODE_WM_NWE |
>  		AT91_SMC_MODE_EXNW_DISABLE |
> @@ -78,7 +78,7 @@ static void at91sam9x5ek_nand_hw_init(void)
>  #else /* CONFIG_SYS_NAND_DBW_8 */
>  		AT91_SMC_MODE_DBW_8 |
>  #endif
> -		AT91_SMC_MODE_TDF_CYCLE(3),
> +		AT91_SMC_MODE_TDF_CYCLE(1),
>  		&smc->cs[3].mode);
>  
>  	writel(1 << ATMEL_ID_PIOCD, &pmc->pcer);
> 

are these changes required to get it working? As I understand your
changes make the timing harder, which will result in less different NAND
devices will be supported. The timing may be exactly the best for the
currently used one, but maybe some change the device in future to a
slightly slower one.
Maybe I'm wrong so tell me please. But if not then I would like to have
a Tested-by from one who owns this board (Bo?)

Best regards

Andreas Bießmann


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