[PATCH v3 1/3] spi: airoha-snfi: en7523: workaround flash damaging if UART_TXD was short to GND

[AngeloGioacchino Del Regno]

Il 20/11/25 05:27, Mikhail Kshevetskiy ha scritto:
> We found that some serial console may pull TX line to GROUND during board
> boot time. Airoha uses TX line as one of it's BOOT pins. This will lead
> to booting in RESERVED boot mode.
> 
> It was found that some flashes operates incorrectly in RESERVED mode.
> Micron and Skyhigh flashes are definitely affected by the issue,
> Winbond flashes are NOT affected.
> 
> Details:
> --------
> DMA reading of odd pages on affected flashes operates incorrectly. Page
> reading offset (start of the page) on hardware level is replaced by 0x10.
> Thus results in incorrect data reading. Usage of UBI make things even
> worse. Any attempt to access UBI leads to ubi damaging. As result OS loading
> becomes impossible.
> 
> Non-DMA reading is OK.
> 
> This patch detects booting in reserved mode, turn off DMA and print big
> fat warning.
> 
> Signed-off-by: Mikhail Kshevetskiy <mikhail.kshevetskiy at iopsys.eu>

This is important enough to get a Fixes tag.

Please resend with the appropriate one, after which:

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno at collabora.com>