Messages in this thread | | | Date | Thu, 31 Jan 2019 13:01:50 +0100 | From | Boris Brezillon <> | Subject | Re: [PATCH 9/9] spi: atmel-quadspi: add support for sam9x60 qspi controller |
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On Wed, 30 Jan 2019 15:08:47 +0000 <Tudor.Ambarus@microchip.com> wrote:
> +/* > + * atmel_qspi_set_address_mode() - set address mode. > + * @cfg: contains register values > + * @op: describes a SPI memory operation > + * > + * The controller allows 24 and 32-bit addressing while NAND-flash requires > + * 16-bit long. Handling 8-bit long addresses is done using the option field. > + * For the 16-bit addresses, the workaround depends of the number of requested > + * dummy bits. If there are 8 or more dummy cycles, the address is shifted and > + * sent with the first dummy byte. Otherwise opcode is disabled and the first > + * byte of the address contains the command opcode (works only if the opcode and > + * address use the same buswidth). The limitation is when the 16-bit address is > + * used without enough dummy cycles and the opcode is using a different buswidth > + * than the address.
Too bad they didn't patch the IP to support 1 to 4 address bytes instead of only 3 or 4 :-(.
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