[PATCH 00/23] RFC: exynos multiplatform support

On Tuesday 05 March 2013, Tomasz Figa wrote:

quoted

With this patch set, we can build mach-exynos as part
of a multiplatform kernel, with the following caveats:

* Only DT based boards are supported

As far as I'm aware, there are plans to drop non-DT Exynos support. Kgene 
should know more on this.

Yes, that was my understanding as well. It might not actually be too 
hard to get multiplatform working with the ATAGS based board files
(we do that on some of the other platforms), but there is probably
no reason to try hard.
 

quoted

* Moving to common-clk breaks things including cpufreq
  and others. Thomas is working on a patch for this

We have several patches internally for fixing things up to run correclty with 
common-clk. I'll see if we can post some patches.

Ok, excellent.

quoted

* We disable the gpio implementation, which also breaks
  stuff, but Thomas has a patch already

The legacy GPIO code is needed only for non-DT case. DT-case uses the new 
pinctrl-samsung driver, which is (AFAIK) multiplatform-aware.

Please have a closer look at the "ARM: exynos: work around missing gpio
code on multiplatform" patch, I think there a few files I had to touch
that actually rely on the legacy gpio code:

* the pm-gpio.c file
* the s3c_i2c0_cfg_gpio function
* the eint irqchip

If none of these are needed for DT-based systems, we should probably
build that code conditionally based on the CONFIG_EXYNOS_ATAGS symbol
I introduced.

quoted

* sparsemem support is not available on multiplatform

There was some discussion some time ago whether we really need sparsemem on 
Exynos. If I remember correctly, it turned out that we don't. So this is not 
really an issue.

Ok, good.
 

quoted

Arnd Bergmann (23):
  ARM: exynos: introduce EXYNOS_ATAGS symbol
  irqchip: exynos: remove dependency on mach/irqs.h
  tty: serial/samsung: prepare for common clock API
  tty: serial/samsung: make register definitions global
  tty: serial/samsung: fix modular build
  ARM: exynos: move debug-macro.S to include/debug/
  i2c: s3c2410: make header file local
  mmc: sdhci-s3c: remove platform dependencies
  usb: exynos: do not include plat/usb-phy.h
  [media] exynos: remove unnecessary header inclusions
  video/exynos: remove unnecessary header inclusions
  thermal/exynos: remove unnecessary header inclusions
  mtd: onenand/samsung: make regs-onenand.h file local
  rtc: s3c: make header file local
  spi: s3c64xx: move to generic dmaengine API
  pwm: samsung: repair the worst MMIO abuses

I'm currently working (in my free time) on a series of cleanup patches 
sanitizing Samsung PWM code for S3C64xx and S5PV210 DT (and multiplatform) 
support.

Ah, nice.

On those platforms it is a bit more complex case as there are two blocks of 
code that access the same hardware - samsung-time (using two PWM channels for 
clocksource and clock events) and pwm-samsung.

Hopefully, I will have some patches ready soon.

How are you planning to solve this? Do you want to have a combined driver that
registers both a clocksource and a pwm?

	Arnd