[PATCH v3 0/8] Add the Quadspi driver for vf610-twr

[Huang Shijie]

于 2013年09月11日 18:41, Mark Brown 写道:
> So why does the SPI driver have references to the opcodes in it?
I admit that the Freescale's quadspi controller is very special
(it is designed too coupled with the SPI Nor FLASH),
it is driven by the LUT registers.

I just quote the comment from the patch 1:


-------------------------------------------------------------
(2) The definition of the LUT register shows below:

---------------------------------------------------
| INSTR1 | PAD1 | OPRND1 | INSTR0 | PAD0 | OPRND0 |
---------------------------------------------------

There are several types of INSTRx, such as:
CMD : the SPI NOR command.
ADDR : the address for the SPI NOR command.
DUMMY : the dummy cycles needed by the SPI NOR command.
....
-------------------------------------------------------------------

The LUT registers needs to be filled with the SPI NOR command, such
Fast-read/Quad-read.
So the Quadspi driver needs to know the spi commands, and that's why the
SPI driver has
references to the spi command opcodes.

 
thanks
Huang Shijie