On 8/5/2017 8:12 AM, Nishanth Menon wrote:
> OMAP5432 did go into production with AVS class0 registers which were
> mutually exclusive from AVS Class 1.5 registers.
> Most OMAP5-uEVM boards use the pre-production Class1.5 which has
> production efuse registers set to 0. However on production devices,
> these are set to valid data.
> scale_vcore logic is already smart enough to detect this and use the
> "Nominal voltage" on devices that do not have efuse registers populated.
> On a test production device populated as follows:
> MPU OPP_NOM:
> => md.l 0x04A0021C4 1
> 4a0021c4: 03a003e9 ....
> (0x3e9 = 1.01v) vs nom voltage of 1.06v
> MPU OPP_HIGH:
> => md.l 0x04A0021C8 1
> 4a0021c8: 03400485 ..@.
> MM OPP_NOM:
> => md.l 0x04A0021A4 1
> 4a0021a4: 038003d4 ....
> (0x3d4 = 980mV) vs nom voltage of 1.025v
> MM OPP_OD:
> => md.l 0x04A0021A8 1
> 4a0021a8: 03600403 ..`.
> CORE OPP_NOM:
> => md.l 0x04A0021D8 1
> 4a0021d8: 000003cf ....
> (0x3cf = 975mV) vs nom voltage of 1.040v
> Since the efuse values are'nt currently used, we do not regress on
> existing pre-production samples (they continue to use nominal voltage).
> But on boards that do have production samples populated, we can leverage
> the optimal voltages necessary for proper operation.
> Tested on:
> a) 720-2644-001 OMAP5UEVM with production sample.
> b) 750-2628-222(A) UEVM5432G-02 with pre-production sample.
> Data based on OMAP5432 Technical reference Manual SWPU282AF (May
> 2012-Revised Aug 2016)
> NOTE: All collaterals on OMAP5432 silicon itself seems to have been
> removed from ti.com, though EVM details are still available:
Reviewed-by: Lokesh Vutla <lokeshvu...@ti.com>
Thanks and regards,
> Signed-off-by: Nishanth Menon <n...@ti.com>
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