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: > http://www.ti.com/tool/OMAP5432-EVM >
Reviewed-by: Lokesh Vutla <lokeshvu...@ti.com> Thanks and regards, Lokesh > Signed-off-by: Nishanth Menon <n...@ti.com> _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot