[U-Boot] [PATCH 5/7] OMAP5: EMIF: Add support for DDR3 device

[Tom Rini]

On 05/22/2012 08:27 AM, R, Sricharan wrote:
>>>>> - ? ? if (!in_sdram)
>>>>> - ? ? ? ? ? ? lpddr2_init(base, regs);
>>>>> + ? ? if (!in_sdram) {
>>>>> + ? ? ? ? ? ? if (omap_revision() != OMAP5432_ES1_0)
>>>>> + ? ? ? ? ? ? ? ? ? ? lpddr2_init(base, regs);
>>>>> + ? ? ? ? ? ? else
>>>>> + ? ? ? ? ? ? ? ? ? ? ddr3_init(base, regs);
>>>>> + ? ? }
>>>>
>>>> In omap4+ land do we have any other way of telling which family we're
>>>> on? ?I ask since I'm preparing to add DDR3 support to am33xx and I'd
>>>> like to switch it over to the common emif framework as well.
>>>>
>>>    I think the SDRAM_TYPE[31:29] EMIF_SDRAM_CONFIG
>>>   register should tell the connected device at reset.
>>>   I will cross confirm this on the board and tell.
>>
>> OK.  I can't find the omap5430 TRM quickly but on the am335x one,
>> SDRAM_TYPE is 3 for DDR3, 2 for DDR2 and 1 for LPDDR1 and 0 for DDR1.
>
>   ah, this is what is there on OMAP5.
>     3 for DDR3
>     4 for LPDDR2-S4,
>     5 for LPDDR2-S2

4/5 are listed as reserved here :( http://www.ti.com/lit/pdf/spruh73

> Atleast DDR3 encoding is same. So we can differentiate bw DDR3 and 2
> in same way.
> Is the reset value set correctly on am335x according to the device connected?

I'll have to do some checking as the code doesn't check that today.

-- 
Tom