Re: AHCI support Port Multiplier problem.

[Luo Dislo <dislo_b_j@yahoo.com.tw>]

Yes, refer to ahci_sb600_softreset() function solved my problem.

Thanks 

--- 11/1/11 (二)，Tejun Heo <tj@kernel.org> 寫道：

> 寄件者: Tejun Heo <tj@kernel.org>
> 主旨: Re: AHCI support Port Multiplier problem.
> 收件者: "Luo Dislo" <dislo_b_j@yahoo.com.tw>
> 副本: jgarzik@pobox.com, linux-ide@vger.kernel.org
> 日期: 2011年1月11日,二,下午10:37
> Hi,
> 
> On Mon, Jan 10, 2011 at 09:46:45AM +0800, Luo Dislo wrote:
> > This is my company(Faraday) implemented AHCI SATA
> controller. Our 
> > controller is not located at PCI bus, but AHB bus(ARM
> based platform).
> > 
> > However, I modify Linux kernel builtin AHCI
> driver(ahci.c) to replace
> > the PCI related code by using platform bus. Just
> pretty similar way 
> > with drivers/ata/ahci_platform.c (Kernel 2.6.35).
> > 
> > I think the problem happens because libata does not
> give up, keep on 
> > expecting the Port Multiplier Signature when we set
> CONFIG_SATA_PMP 
> > to 1. 
> > 
> > I know how to fix this problem, just add
> AHCI_HFLAG_NO_PMP to
> > AHCI_HFLAGS when I connect hard drive to the
> controller. Meanwhile,
> > when I want to connect the Port Muliplier to my
> controller, I need
> > to remove AHCI_HFLAG_NO_PMP from AHCI_HFLAGS.
> > 
> > I don't think this is a good solution because I have
> to compile two
> > version of my code. It does not make sense. We set
> CONFIG_SATA_PMP
> > to 1 and inside the driver code DOES NOT have
> AHCI_HFLAG_NO_PMP just
> > means that controller support Port Multiplier but the
> device
> > connecting to the port might be others type.
> 
> Please take a look at ahci_sb600_softreset() in
> ahci.c.  The
> controller had the same problem.  Preferably, please
> fix your
> controller but as there are more than one controller with
> this
> problem, we probably should implement it as a quirk in
> libahci.c.
> 
> Thanks.
> 
> -- 
> tejun
>