Luo Dislo <dislo_b_j <at> yahoo.com.tw> writes: > > Hello, > > 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. We have a similar issue on cns3xxx http://www.spinics.net/lists/linux-ide/msg39512.html http://www.spinics.net/lists/linux-ide/msg39859.html Could you try the following patch with CONFIG_SATA_PMP enabled and see if it fix the issue? If so, then it would be the same issue. --- drivers/ata/libahci.c | 7 ++++++- 1 files changed, 6 insertions(+), 1 deletions(-) diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c index ebc08d6..081548f 100644 --- a/drivers/ata/libahci.c +++ b/drivers/ata/libahci.c @@ -1302,10 +1302,15 @@ static int ahci_softreset(struct ata_link *link, unsigned int *class, unsigned long deadline) { int pmp = sata_srst_pmp(link); + int ret; DPRINTK("ENTER\n"); - return ahci_do_softreset(link, class, pmp, deadline, ahci_check_ready); + ret = ahci_do_softreset(link, class, pmp, deadline, ahci_check_ready); + if (ret && pmp) + return ahci_do_softreset(link, class, 0, deadline, + ahci_check_ready); + return ret; } EXPORT_SYMBOL_GPL(ahci_do_softreset); -- > > Regards, > > Dislo > > --- 11/1/8 (å)ïTejun Heo <tj <at> kernel.org> åéï > > > åäè: Tejun Heo <tj <at> kernel.org> > > äæ: Re: AHCI support Port Multiplier problem. > > æäè: "Luo Dislo" <dislo_b_j <at> yahoo.com.tw> > > åæ: jgarzik <at> pobox.com, linux-ide <at> vger.kernel.org > > ææ: 2011å1æ8æ,å,äå5:25 > > Hello, > > > > On Fri, Jan 07, 2011 at 10:55:14AM +0800, Luo Dislo wrote: > > > I am using AHCI driver, when CONFIG_SATA_PMP is set > > and the ahci > > > driver DOES NOT have AHCI_HFLAG_NO_PMP. Libata sends > > Software Reset > > > with PMP=0xF, trying to detect if Port Multiplier > > connected to the > > > port. Unfortunately, if I plugged in general Hard > > drive, my > > > controller failed to identify the hard drive. > > > > > > What I observed was that libata always sent Software > > Reset with > > > PMP=0xF and I guessed expecting signature is > > 0x96690101. I think > > > libata should give up if the device does not return > > the Port > > > Multiplier signature at the first time and take the > > signature value > > > from device as the real device connnecting to the port > > now. > > > > > > What we said "support" PMP does not mean the port can > > only connnect > > > to Port Multiplier. It might connect with hard drive > > or ATAPI > > > device. > > > > Which controller is this? Can you please post the > > output of "lspci > > -nn"? SB600 had this problem and needed workaround > > but later SBs > > fixed it. Looks like someone else screwed up > > similarly. > > > > Thanks. > > > > -- > > tejun Best Regards, Mac Lin -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
