In-Circuit Programming of SPI NOR Flash

[Arwen]

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Does this mean - at least to the best knowledge - that a desired uBoot image could be flashed in place to the SPI? Is there any special parameterization, other than the usual image, that would be required?
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The SPI can be flashed from the OS, no special hardware needed. Only special software. The U-Boot image would be similar to an eMMC or SD card image.

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It seems that the risk of screwing this up is minimal. Since the default state is a blank SPI image, then any failed attempts could be recovered by zeroing the SPI as you describe. Is this also right?

Thanks much,

Correct. If something does go wrong, you would be able to over-write the SPI with zeros and then the SoC would follow the next device, (eMMC, then SD card).

So a bad SPI image would soft-brick a Pinebook Pro. Annoying recovery, but possible without cutting a leg off the SPI, or un-soldering the SPI.