On 03/18/2016 11:09 AM, Murali Karicheri wrote:
> On 03/18/2016 07:28 AM, Lorenzo Pieralisi wrote:
>> On Thu, Mar 17, 2016 at 05:28:31PM -0400, Murali Karicheri wrote:
>>
>> [...]
>>
>>>> The only ways I see that PCI_PROBE_ONLY can be set on ARM are if you have
>>>> "linux,pci-probe-only" in your DT or you boot with "pci=firmware".
>>>>
>>>> I expect you're in this path:
>>>>
>>>> ahci_init_one
>>>> pcim_enable_device
>>>> pci_enable_device
>>>> pci_enable_device_flags(dev, IORESOURCE_MEM | IORESOURCE_IO)
>>>> # build "bars" mask
>>>> do_pci_enable_device(dev, bars)
>>>> pcibios_enable_device
>>>> if (pci_has_flag(PCI_PROBE_ONLY))
>>>> return 0;
>>>> pci_enable_resources
>>>>
>>>> Can you add a little debug code like this to verify that we're in this
>>>> path?
>>>
>>> Yes we are in the path.
>>>
>>>
>>> [ 1.557561] ahci_init_one
>>> [ 1.560214] ahci 0000:01:00.0: version 3.0
>>> [ 1.564302] pcim_enable_device
>>> [ 1.567349] pci_enable_device
>>> [ 1.570340] pci_enable_device_flags
>>> [ 1.573824] do_pci_enable_device
>>> [ 1.577042] pcibios_enable_device
>>> [ 1.580380] pci_enable_resources
>>
>> So resources are actually enabled (ie PCI_PROBE_ONLY is not set)
>> and that makes sense otherwise you would not be able to use the
>> MEM resources anyway (ie they would not be enabled).
>>
>> I suspect the PCI dev IO resources were reset in reset_resource() in
>> assign_requested_resource_sorted(), hence the bar mask that is built
>> in pci_enable_device_flags() does not contain the IO resources,
>> it would be helpful if you can print the bar mask passed to
>> pcibios_enable_device() (ie the mask parameter).
>
> Here it is
>
> [ 1.556507] ahci_init_one
> [ 1.559124] ahci 0000:01:00.0: version 3.0
> [ 1.563246] pcim_enable_device
> [ 1.566294] pci_enable_device
> [ 1.569252] pci_enable_device_flags
> [ 1.572766] do_pci_enable_device
> [ 1.575985] pcibios_enable_device 60
> [ 1.579551] pci_enable_resources
>
I see only see memory resources passed in
[ 1.592835] pci_enable_resources, mask 60
[ 1.596843] ahci 0000:01:00.0: res 5: [mem 0x60000000-0x600001ff]
[ 1.602962] ahci 0000:01:00.0: res 6: [mem 0x60100000-0x6010ffff pref]
> I know that some of our customers use PCIe SATA from u-boot and would
> like to honor the assignment in Linux space.. I believe they use PCI_PROBE_ONLY
> by setting the bootarg. So Keystone PCI should work in both cases.
>
> Murali
>>
>> Not saying that's what should happen, I think that's what's happening,
>> that's the only reason I see why you do not have pci_enable_resources()
>> failures when you remove the IO range from the host bridge.
>>
>> Lorenzo
>>
>>> [ 1.583608] ahci 0000:01:00.0: limiting MRRS to 256
>>> [ 1.588595] ahci 0000:01:00.0: AHCI 0001.0000 32 slots 2 ports 6 Gbps 0x3 impl SATA mode
>>> [ 1.596716] ahci 0000:01:00.0: flags: 64bit ncq sntf led only pmp fbs pio slum part sxs
>>> [ 1.606183] scsi host0: ahci
>>> [ 1.609448] scsi host1: ahci
>>> [ 1.612636] ata1: SATA max UDMA/133 abar m512@0x60000000 port 0x60000100 irq 82
>>> [ 1.619974] ata2: SATA max UDMA/133 abar m512@0x60000000 port 0x60000180 irq 82
>>>
>>>>
>>>>> I looked at pci_enable_resources()
>>>>>
>>>>> for (i = 0; i < PCI_NUM_RESOURCES; i++) {
>>>>> if (!(mask & (1 << i)))
>>>>> continue;
>>>>>
>>>>> r = &dev->resource[i];
>>>>
>>>> dev_info(&dev->dev, "BAR %d %pR mask %#04x parent %p\n", i, r, mask, r->parent);
>>>>
>>>>>
>>>>> if (!(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
>>>>> continue;
>>>>> if ((i == PCI_ROM_RESOURCE) &&
>>>>> (!(r->flags & IORESOURCE_ROM_ENABLE)))
>>>>> continue;
>>>>>
>>>>> if (r->flags & IORESOURCE_UNSET) {
>>>>> dev_err(&dev->dev, "can't enable device: BAR %d %pR not assigned\n",
>>>>> i, r);
>>>>> return -EINVAL;
>>>>> }
>>>>>
>>>>> if (!r->parent) {
>>>>> dev_err(&dev->dev, "can't enable device: BAR %d %pR not claimed\n",
>>>>> i, r);
>>>>> return -EINVAL;
>>>>> }
>>>>>
>>>>> I don't see the error "can't enable device: BAR %d %pR not assigned" , so it doesn't
>>>>> depend on IO bar as you mention below or is it in a different function?
>>>>
>>>
>>>
>>> --
>>> Murali Karicheri
>>> Linux Kernel, Keystone
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>
>
--
Murali Karicheri
Linux Kernel, Keystone
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