[PATCH 2/4] ARM i.MX: add SoC type detection for i.MX6SL

[Sascha Hauer]

Hi Alexander,

On Mon, Nov 28, 2016 at 10:27:33AM +0100, Alexander Kurz wrote:
> The i.MX6 series SoC type is determined by barebox by examining the
> USB_ANALOG_DIGPROG aka IMX6_ANATOP_SI_REV register. This register is located
> at a common offset for all mx6 SoC - except for i.MX6SL where a different
> offset is used. This creates a dilemma while distinguishing the mx6sl from
> non-mx6sl SOC since the SoC type identification register location is type
> specific itself.
> 
> Access to undocumented and probably invalid or unpredictable registers should
> be avoided as possible. For the mx6sl detection an access to the general
> USB_ANALOG_DIGPROG @0x260 cannot be avoided when running on mx6sl. This
> register contained the value 0x00014009 for different mx6sl Rev. 1.2 based
> e-book readers using MCIMX6L7DVN10AB and MCIMX6L8DVN10AB SoC. This
> implementation assumes the value of MAJOR_UPPER (here 0x01) to be smaller
> than the smallest non-6sl MAJOR_UPPER (0x61 for mx6s).

The i.MX6SL code would be quite straight forward and easy to merge
without this handicap. I'll probably need a few more days to swallow
this pill. I assume you already searched for better ways to detect a
i.MX6SL, right?

Sascha

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