[U-Boot] [PATCH v2 2/3] mx23: Enable tRAS lockout (24 bit of HW_DRAM_CTL08) as in imx-bootlets

Marek Vasut marek.vasut at gmail.com
Tue Jan 29 03:33:56 CET 2013


Dear Otavio Salvador,

> This enables the 'Fast Auto Pre-Charge' found in the memory chip.
> 
> Signed-off-by: Otavio Salvador <otavio at ossystems.com.br>
> ---
> Changes in v2:
> - Improve commit message
> 
>  arch/arm/cpu/arm926ejs/mxs/spl_mem_init.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/arm/cpu/arm926ejs/mxs/spl_mem_init.c
> b/arch/arm/cpu/arm926ejs/mxs/spl_mem_init.c index 836e636..a9efd87 100644
> --- a/arch/arm/cpu/arm926ejs/mxs/spl_mem_init.c
> +++ b/arch/arm/cpu/arm926ejs/mxs/spl_mem_init.c
> @@ -90,7 +90,7 @@ static uint32_t dram_vals[] = {
>  #elif defined(CONFIG_MX23)
>  	0x01010001, 0x00010100, 0x01000101, 0x00000001,
>  	0x00000101, 0x00000000, 0x00010000, 0x01000001,
> -	0x00000000, 0x00000001, 0x07000200, 0x00070202,
> +	0x01000000, 0x00000001, 0x07000200, 0x00070202,
>  	0x02020000, 0x04040a01, 0x00000201, 0x02040000,
>  	0x02000000, 0x19000f08, 0x0d0d0000, 0x02021313,
>  	0x02061521, 0x0000000a, 0x00080008, 0x00200020,

I went through the u-boot mem init and detected you apparently added the 
following undocumented portion of code (the writel((1 << 24 ...) already:

112 static void initialize_dram_values(void)
113 {
114         int i;
115 
116         mxs_adjust_memory_params(dram_vals);
117 
118         for (i = 0; i < ARRAY_SIZE(dram_vals); i++)
119                 writel(dram_vals[i], MXS_DRAM_BASE + (4 * i));
120 
121 #ifdef CONFIG_MX23
122         writel((1 << 24), MXS_DRAM_BASE + (4 * 8));
123 #endif
124 }

It does enable the TRANS_LOCKOUT. So what the heck is going on here? Are you 
coding this stuff at random now ? WHAT THE FUCK IS HAPPENING HERE ?!

Best regards,
Marek Vasut


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