[U-Boot] [PATCH v3 6/7] mxs: spl_mem_init: Skip the initialization of some DRAM_CTL registers

Marek Vasut marex at denx.de
Fri May 3 04:26:48 CEST 2013


Dear Fabio Estevam,

> From: Fabio Estevam <fabio.estevam at freescale.com>
> 
> HW_DRAM_CTL27, HW_DRAM_CTL28 and HW_DRAM_CTL35 are not initialized as per
> FSL bootlets code.
> 
> mx23 Reference Manual mark HW_DRAM_CTL27 and HW_DRAM_CTL28 as "reserved".
> 
> HW_DRAM_CTL8 is setup as the last element.
> 
> So skip the initialization of these DRAM_CTL registers.
> 
> Signed-off-by: Fabio Estevam <fabio.estevam at freescale.com>
> ---
> Changes since v2:
> - None
> Changes since v1:
> - To avoid polluting the mx28 case, separate the function definition in
> mx23 and for mx28.
> 
>  arch/arm/cpu/arm926ejs/mxs/spl_mem_init.c |   16 ++++++++++++++--
>  1 file changed, 14 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/arm/cpu/arm926ejs/mxs/spl_mem_init.c
> b/arch/arm/cpu/arm926ejs/mxs/spl_mem_init.c index df25535..bf58058 100644
> --- a/arch/arm/cpu/arm926ejs/mxs/spl_mem_init.c
> +++ b/arch/arm/cpu/arm926ejs/mxs/spl_mem_init.c
> @@ -110,6 +110,7 @@ __weak void mxs_adjust_memory_params(uint32_t
> *dram_vals) {
>  }
> 
> +#ifdef CONFIG_MX28
>  static void initialize_dram_values(void)
>  {
>  	int i;
> @@ -118,15 +119,26 @@ static void initialize_dram_values(void)
> 
>  	for (i = 0; i < ARRAY_SIZE(dram_vals); i++)
>  		writel(dram_vals[i], MXS_DRAM_BASE + (4 * i));
> +}
> +#else
> +static void initialize_dram_values(void)
> +{
> +	int i;
> +
> +	mxs_adjust_memory_params(dram_vals);
> +
> +	for (i = 0; i < ARRAY_SIZE(dram_vals); i++) {
> +		if (!(i == 8 || i == 27 || i == 28 || i == 35))

if (foo || bar || baz)
 continue;
writel();

This will be much more readable.

> +			writel(dram_vals[i], MXS_DRAM_BASE + (4 * i));
> +	}
> 
> -#ifdef CONFIG_MX23
>  	/*
>  	 * Enable tRAS lockout in HW_DRAM_CTL08 ; it must be the last
>  	 * element to be set
>  	 */
>  	writel((1 << 24), MXS_DRAM_BASE + (4 * 8));
> -#endif
>  }
> +#endif
> 
>  static void mxs_mem_init_clock(void)
>  {

Best regards,
Marek Vasut


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