[RFC PATCH dev-5.1 5/6] i2c: aspeed: add buffer mode transfer support

[Tao Ren]

On 6/21/19 3:34 PM, Jae Hyun Yoo wrote:
> On 6/21/2019 3:29 PM, Tao Ren wrote:
>> On 6/20/19 12:49 PM, Jae Hyun Yoo wrote:
>>> Byte mode currently this driver uses makes lots of interrupt call
>>> which isn't good for performance and it makes the driver very
>>> timing sensitive. To improve performance of the driver, this commit
>>> adds buffer mode transfer support which uses I2C SRAM buffer
>>> instead of using a single byte buffer.
>>>
>>> Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo at linux.intel.com>
>>
>> Let me apply the patch to my ast2500 BMC platform and will share results earlier next week.
> 
> Thanks Tao! It would be helpful.

Hi Jae,

I applied patches 1-5 (except DMA mode) to my local tree: buffer mode is enabled by default, and reg_base/buf_base also looks correct to me, but I'm seeing some pca9548/lm75 driver binding failures on CMM BMC. I'm wondering if I missed some dependency patches as I'm still working on kernel 5.0 (although i2c-aspeed.c is up to date)?

BTW, USB is enabled in my image because both EHCI and UHCI are needed. But I guess it won't impact buffer mode?

Let me see if I can quickly set up kernel 5.1 and re-run testing; meanwhile, kindly let me know what information will be helpful for your debugging.


Cheers,

Tao