Messages in this thread | | | Date | Thu, 04 Nov 2010 21:30:26 +0100 | From | Eric Bénard <> | Subject | Re: [PATCH 2/2] ARM: imx: Add mx53 support to common msl functions. |
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Hi Dinh,
Le 04/11/2010 20:21, Nguyen Dinh-R00091 a écrit : > Reading the ROM code is probably the most reliable way to get the correct > silicon revision. Because the ROM that is on the chip is "most likely" > up-to-date with the silicon. "Most likely" means that 95% of the time, when > you get a new silicon, the ROM code will get updated. There is still a > chance that a new silicon will not require a ROM update. > > Also the other reason is that sometimes the fuses that identify the silicon > revision that are used by the IIM are sometimes not blown to reflect the > correct revision in pre-production parts. MX51 is a post production part, > so in theory, the fuses are blown correctly. But since we made MX51 boards > available prior to going into production, reading from the IIM is not as > reliable as reading the ROM. > Don't you think we should use the documented register which (if we believe the documentation) should be 100% reliable for production CPU instead of this undocumented method which from what you say is 95% reliable and here to handle the case of pre production CPU ?
The same problem occured on i.MX35 silicon 2.1 which where not correctly detected using the ROM code.
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