[U-Boot] [PATCH] drivers: mtd: add Microchip PIC32 internal non-CFI flash driver.

[Purna Chandra Mandal]

On 03/10/2016 07:11 PM, Jagan Teki wrote:
> On Thursday 10 March 2016 06:42 PM, Purna Chandra Mandal wrote:
>> PIC32 embedded flash banks are memory mapped, directly read by CPU,
>> and programming (erase followed by write) operation on them are
>> handled by on-chip NVM controller.
>
> Can you please add some more description to understand bit more, which kind of flash it is, parallel NOR?
>
Jagan,

These are parallel NOR flash divided into number of banks to allow
erase/programming in one while fetch/execution continues from other.
As the flash is memory-mapped code stored can be directly executed
from flash (XIP), also there is additional hardware logic to prefetch
and cache contents to improve code execution. These flash can also
be used to store user data.

In PIC32 there are two sets of embedded flash memory of same type -
boot flash, and program flash; early-boot-code executes from
boot-flash and one bank of program-flash is used for u-boot, other
bank for environment.

> thanks!
> -- 
> Jagan.