On Wed, Apr 23, 2014 at 10:19:30AM +0100, Kukjin Kim wrote:
Arnd Bergmann wrote:
On Wednesday 16 April 2014, Jingoo Han wrote:
Samsung GH7 has four PCIe controllers which can be used as root complex for PCIe interface.
Signed-off-by: Jingoo Han jg1.han@samsung.com
drivers/pci/host/Kconfig | 2 +- drivers/pci/host/pci-exynos.c | 135
++++++++++++++++++++++++++++++++++++++---
2 files changed, 126 insertions(+), 11 deletions(-)
- Byungho An, Ilho Lee
Hi Arnd,
Can you explain how much the GH7 and Exynos front-ends actually have in common? Would it make sense to have a separate driver for gh7?
Basically, ARMv8 based GH7 has same PCIe hardware IP with previous ARMv7 based exynos5440, several features in PCIe are different though. In other words, basic functionalities for PCIe are same. So I think, would be nice if we could use one PCIe device driver for both SoCs.
However, if we need to support the PCIe with each own device driver because of difference of 32bit and 64bit, please kindly let us know. Honestly, I'm not sure about that right now.
Hi Kukjin,
I will let Arnd offer his view as a maintainer of DT enabled platforms for arch/arm, but in my understanding the goal is to convert individual host bridge drivers to use my patch series directly, as they intentionally don't depend on any arch specific code and then leave the existing bios32 code for the non-DT platforms and the ones that do not see the need to convert to the framework.
Rob Herring has posted an example on how he can add support for a host bridge running under arm32 that uses my framework, so it is not an impossible task and can be used as an example for future conversions.
Does that make sense?
Best regards, Liviu
Also, if gh7 is expected to run a full firmware, I think you should do all the setup in the firmware before booting Linux, and just do the required run-time operations in the driver itself.
Well, we're expecting that all the setup should be done by the device driver in kernel not firmware.
Thanks, Kukjin