serial Flash over SPI as rootdevice?
Hello,
is it currently possible to use a serial Flash connected over SPI to use as a rootdevice? If not, would it be possible and which drivers need to be written for that then?
Best regards,
Alexander
Hello Alexander:
Quoted 4 lines
is it currently possible to use a serial Flash connected over SPI to use as a rootdevice?
If not, would it be possible and which drivers need to be written for that then?
Yes, it is certainly possible; we are doing it ourselves. No extra drivers are required for this beyond those you need anyway (SPI driver, SPI flash driver).
The real problem, though, is that you cannot boot from standard SPI flash. For this, you need memory which can be read directly by the CPU, such as parallel NOR flash.
Best regards,
Thomas
Hello Thomas,
Quoted 10 lines · On Tuesday 09 April 2013 10:21:26, [email protected] wrote:
Hello Alexander:
Quoted 4 lines
is it currently possible to use a serial Flash connected over SPI to use as a rootdevice?
If not, would it be possible and which drivers need to be written for that then?Yes, it is certainly possible; we are doing it ourselves. No extra drivers are required for this beyond those you need anyway (SPI driver, SPI flash driver).
That sound great. Could you please point me to the driver needed for that? Do you have any performance comparisons to e.g. NOR flash?
Quoted 3 lines
The real problem, though, is that you cannot boot from standard SPI flash. For this, you need memory which can be read directly by the CPU, such as parallel NOR flash.
Well, the idea is to use an AT91 which can boot directly from serial flash with it's own ROM code. This would load the bootloader (will be u-boot likely) which in turns needs to fetch the kernel from the serial flash too. Should be possible, no?
Best regards,
Alexander