On Tue, Sep 22, 2020 at 07:49:02PM +0800, Chuanhong Guo wrote:

>  		if ((op->data.dir == SPI_MEM_DATA_IN) &&
>  		    mtk_nor_match_read(op)) {
> +			// limit size to prevent timeout calculation overflow
> +			if (op->data.nbytes > 0x400000)
> +				op->data.nbytes = 0x400000;

If there's a limit on transfer sizes there should also be a
max_transfer_size or max_message_size set (which we should pay attention
to in the core for flash stuff but IIRC we didn't do that yet).