ioremap to a specific virtual address
Arnd Bergmann
arnd at arndb.de
Fri Mar 23 11:20:22 EDT 2012
On Friday 23 March 2012, jonsmirl at gmail.com wrote:
> I will need to check how similar the chips actually are. NXP did not
> use primecells in the lpc31xx family.
>
> I'd be happy to have some help. My trees are here:
> https://github.com/jonsmirl
I've taken a brief look at your tree, some comments:
* Once you're done with the DT conversion, you should be able to
completely remvoe the three board files. You probably know that already
* We're merging the new common clock framework in v3.4. Once that has
matured, all new platforms will be required to use it. You should probably
move to that already.
* The dma driver uses a nonstandard interface and should be moved to
drivers/dma, using the dmaengine API.
* The __REG needs to be removed. All MMIO register accesses should go
through readl/writel or readl_relaxed/writel_relaxed, using a pointer
you get from ioremap.
* gpio*.c should get moved to drivers/gpio/gpio-lpc31xx. If it's similar
to the 32xx version, merge the two
* i2c.c should no longer be needed with the device tree, but you might
have to add stuff to i2c-pnx.c. That file is shared with pnx4008 and
lpc32xx.
* irq.c will eventually go to drivers/irqchip/. We have a plan to create
that directory, but nobody has started moving drivers there.
* Some of the header files have been removed on other platforms, you
should do the same.
* Regarding the static mappings, it certainly makes sense to map all of
ABP01_PHYS and IO_APB2_PHYS using 1MB mappings, for performance reasons,
and I guess you need INTC_PHYS to be mapped, too, for the interrupt
controller code to work. However, none of the drivers should be aware
of this and just call ioremap anyway, which will now return an address
from the static mapping.
Arnd
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