Re: Enabling MSI on the Asus Vintage AH-1

Pyun YongHyeon wrote:
> On Sat, Dec 23, 2006 at 09:54:58PM +0000, Bruce M. Simpson wrote:
>  > Hi,
>  > 
>  > It looks like MSI was detected, but not used by the msk(4) driver on the 
>  > Asus Vintage AH-1.
>  > 
>  > This is a uniprocessor Athlon64 system. The PCI bridges on this system 
>  > aren't in the MSI blacklist, however, there are several odd messages 
>  > regarding a non-default MSI window. Looking at the code suggests it 
>  > expects to see the MSI window at 0xfee00000.
>  > 
>  > BTW: This system's on-board SATA controller stopped working with 6.2-RC, 
>  > so I'm using an add-on PCI-e card for SATA to connect the root disk.
>  > 
>  > pcib0: <ACPI Host-PCI bridge> port 0xcf8-0xcff on acpi0
>  > pci0: <ACPI PCI bus> on pcib0
>  > pci0: physical bus=0
> 
> [...]
> 
>  > pcib2: <ACPI PCI-PCI bridge> at device 6.0 on pci0
>  > pcib2:   secondary bus     2
>  > pcib2:   subordinate bus   2
>  > pcib2:   I/O decode        0xc000-0xcfff
>  > pcib2:   memory decode     0xfe400000-0xfe4fffff
>  > pcib2:   no prefetched decode
>  > pci2: <ACPI PCI bus> on pcib2
>  > pci2: physical bus=2
>  > found-> vendor=0x11ab, dev=0x4362, revid=0x19
>  >        bus=2, slot=0, func=0
>  >        class=02-00-00, hdrtype=0x00, mfdev=0
>  >        cmdreg=0x0107, statreg=0x4010, cachelnsz=16 (dwords)
>  >        lattimer=0x00 (0 ns), mingnt=0x00 (0 ns), maxlat=0x00 (0 ns)
>  >        intpin=a, irq=5
>  >        powerspec 2  supports D0 D1 D2 D3  current D0
>  >        VPD Ident: Marvell Yukon 88E8053 Gigabit Ethernet Controller
>  >        PN: Yukon 88E8053
>  >        EC: Rev. 1.9
>  >        MN: Marvell
>  >        SN: AbCdEfG32a88a
>  >        CP: id 1, BAR16, off 0x3cc
>  >        RV: 0x24
>  >        MSI supports 2 messages, 64 bit
>           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> I think Yukon II supports one MSI message. But all systems I know
> reported that it supports two MSI messages. This is main reason why
> msk(4) doesn't use MSI ATM. I don't know why Yukon II claims to
> support two MSI messages.(for dual port MAC configuraiton?)

My guess is that it advertises 2 messages for the dual-port 
configuration.  The intention is probably that the driver would
run a loop where it allocates a message as it configures each port.
So if you only have a single port, then you only allocate a single
message and ignore the other one.  This looks like it will be hard to
fit into the msk+mskc code that is there right now.

> 
> You can force to use MSI by assigning 'msic = 1' before calling
> pci_alloc_msi(9) in mskc_attach(). However it wouldn't work if you
> reload the msk(4) again. Other than that it works well with MSI.

I don't understand why there would be a failure here.  Can you explain?

Scott