11-09-2021, 03:51 PM
(11-09-2021, 03:46 PM)z4v4l Wrote:(09-17-2021, 04:50 PM)dieselnutjob Wrote: Why with the ROCKPro64 the default is to boot eMMC and you have to set a jumper disabling eMMC if you want to boot from SD card, whereas, with the PineBook Pro the microSD card is a higher boot priority than the eMMC ?there is ROM code boot order and uboot boot order. the former is hardcoded into SoCs and cannot be changed. it first checks SPI NOR/NAND, then eMMC and then SD.
Given that they have the same SoC what is controlling this boot order?
Quote:One thing I like about the RK3399 is that if an internal eMMC is corrupted or something then one can just put an SD card in and boot that, so I would say very safe from bricking. OK that creates some security issues for normal device manufacturers (I guess) but for open source hacking it's great. Is the RK3566 the same?it's not that easy. if you have the onboard eMMC "corrupted", that doesn't necessarily mean, you can put an SD card and get booted from it. it depends on how exactly the former is "corrupted". if ID block, that indicates to the ROM code that the payload is here, is still valid, then you easily get a bricked board. and having onboard SPI wouldn't make it any safer, rather opposite, since NOR devices are harder to deal with. apart from gating the offending device off, the only hope is entering the mask rom mode (by pressing the appropriate button) and erasing the corrupted storage through USB, using rockchip tools.
But I guess, rk3566 isn't any different from rk3399 - I bet, all rockchip SoCs have the same ROM code boot order. On Allwinner SoCs, ROM code really first checks SD interface before eMMC, but this goodie is rather rare, because for, say phones, such an order would mean easy hackability, which vendors would hardly be happy about.
I believe on the Quartz64 that if there is both an eMMC module and a microSD card then it boots the microSD card.
The difference with the Pinebook Pro is that there is an SPI chip that boots before either.