[U-Boot] [PATCH] powerpc/mpc85xx: Add support for single source clocking

[York Sun]

On 12/09/2013 01:28 AM, Priyanka.Jain at freescale.com wrote:
> Hello York,
> 
> I am not able to find mail which contains your comment on to undefined CONFIG_DDR_CLK_FREQ, so replying on original mail.
> 
> ----
> You are right that we don't need to define CONFIG_DDR_CLK_FREQ in case of single source clocking. 
> But as T1040QDS supports both single source clocking and separate clocking (for DDR and sysclk) and we intend to keep single u-boot binary for both modes, we need a mechanism to decide clocking mode at runtime. We thought of implementing it via rcw bit. Please suggest if there is some other good way to do so.


I am thinking this pseudo code

#ifdef CONFIG_SINGLE_SOURCE_CLK
	if (test)
		sys_info->freq_ddrbus = CONFIG_SYS_CLK_FREQ;
	else
#endif
#ifdef CONFIG_DDR_CLK_FREQ
		sys_info->freq_ddrbus = CONFIG_DDR_CLK_FREQ;
#else
		sys_info->freq_ddrbus = sysclk;
#endif

York