Use the MMU hardware to set up 1:1 mappings between physical and virtual
addresses. This allows us to bypass the cache when accessing the flash
without having to do any physical-to-virtual address mapping in the CFI
driver.
The virtual memory mappings are defined at compile time through a sorted
array of virtual memory range objects. When a TLB miss exception
happens, the exception handler does a binary search through the array
until it finds a matching entry and loads it into the TLB. The u-boot
image itself is covered by a fixed TLB entry which is never replaced.
This makes the 'saveenv' command work again on ATNGW100 and other boards
using the CFI driver, hopefully without breaking any rules.
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
- Separate the portmux configuration functionality from the GPIO pin
control API.
- Separate the controller-specific code from the chip-specific code.
- Allow "ganged" port configuration (multiple pins at once).
- Add more flexibility to the "canned" peripheral select functions:
- Allow using more than 23 address bits, more chip selects, as
well as NAND- and CF-specific pins.
- Make the MACB SPEED pin optional, and choose between MII/RMII
using a parameter instead of an #ifdef.
- Make it possible to use other MMC slots than slot 0, and support
different MMC/SDCard data bus widths.
- Use more reasonable pull-up defaults; floating pins may consume a
lot of power.
- Get rid of some custom portmux code from the mimc200 board code. The
old gpio/portmux API couldn't really handle its requirements, but
the new one can.
- Add documentation.
The end result is slightly smaller code for all boards. Which isn't
really the point, but at least it isn't any larger.
This has been verified on ATSTK1002 and ATNGW100. I'd appreciate if
the board maintainers could help me test this on their boards. In
particular, the mimc200 port has lost a lot of code, so I'm hoping Mark
can help me out.
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Cc: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Cc: Mark Jackson <mpfj@mimc.co.uk>
Cc: Alex Raimondi <alex.raimondi@miromico.ch>
Cc: Julien May <julien.may@miromico.ch>
Changes since v1:
* Enable pullup on NWAIT
* Add missing include to portmux-pio.h
* Rename CONFIG_PIO2 -> CONFIG_PORTMUX_PIO to match docs
The Hammerhead platform is built around a AVR32 32-bit microcontroller
from Atmel. It offers versatile peripherals, such as ethernet, usb
device, usb host etc.
The board also incooperates a power supply and is a Power over Ethernet
(PoE) Powered Device (PD).
Additonally, a Cyclone III FPGA from Altera is integrated on the board.
The FPGA is mapped into the 32-bit AVR memory bus. The FPGA offers two
DDR2 SDRAM interfaces, which will cover even the most exceptional need
of memory bandwidth. Together with the onboard video decoder the board
is ready for video processing.
For more information see: http:///www.miromico.com/hammerhead
Signed-off-by: Julien May <mailinglist@miromico.ch>
[haavard.skinnemoen@atmel.com: various small fixes and adaptions]
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
