Re: dra7xx pci driver broken on dra7xx-evm

Re: dra7xx pci driver broken on dra7xx-evm

[Suman Anna]

On 01/06/2016 11:17 PM, Kishon Vijay Abraham I wrote:
> Hi,

+ Tero, Tony and linux-omap

> 
> On Thursday 07 January 2016 03:15 AM, Richard Cochran wrote:
>>
>> The dra7xx-evm box freezes hard at the very first PCI bus access, the
>> call to in dra7xx_pcie_readl() in dra7xx_pcie_probe().
>>
>> The out-of-tree 3.14.53 TI driver performs a reset via platform data,
>> calling omap_device_assert_hardreset() by hook and crook.

Yeah, this is the only feasible way and not break multi-arch atm until a
reset framework is in place. We have couple of drivers (omap_iommu and
wkup_m3_rproc) following this approach.

>>
>> Adding the reset into the mainline driver cures the freeze.


>>
>> Question: How on earth is this driver supposed to work?
> 
> It doesn't work out of the box in mainline. (Every time I post a PCI patch, I
> add the pdata-quirks mechanism to test it). The pdata-quirks mechanism used in
> TI tree is not an upstream-able solution. Something like this [1] was done for
> performing reset. Not sure the latest state of that. Dan? Suman?

Yeah, [1] is very old, and it doesn't deal with the hwmod integration
for pm_runtime API usage. Tero has posted another revamped series [2]
with hwmod integration, and it needs to be refreshed with few additional
patches and fixes. It will probably take couple of releases before it
hits mainline. So, I guess it is then a question of picking up the pdata
quirks solution for interim to get the driver functional until the reset
framework hits mainline, or mark the driver as broken.

regards
Suman

> 
> [1] -> https://patches.linaro.org/33797/

[2] http://marc.info/?l=linux-omap&m=144310496514782&w=2

Re: dra7xx pci driver broken on dra7xx-evm

[Tony Lindgren]

* Suman Anna <s-anna@ti.com> [160107 13:26]:
> On 01/06/2016 11:17 PM, Kishon Vijay Abraham I wrote:
> > Hi,
> 
> + Tero, Tony and linux-omap
> 
> > 
> > On Thursday 07 January 2016 03:15 AM, Richard Cochran wrote:
> >>
> >> The dra7xx-evm box freezes hard at the very first PCI bus access, the
> >> call to in dra7xx_pcie_readl() in dra7xx_pcie_probe().
> >>
> >> The out-of-tree 3.14.53 TI driver performs a reset via platform data,
> >> calling omap_device_assert_hardreset() by hook and crook.
> 
> Yeah, this is the only feasible way and not break multi-arch atm until a
> reset framework is in place. We have couple of drivers (omap_iommu and
> wkup_m3_rproc) following this approach.

Sounds like doing reset with platform data is the way to go until the
reset controller works.

Regards,

Tony

Re: dra7xx pci driver broken on dra7xx-evm

[Kishon Vijay Abraham I]

Hi,

On Friday 08 January 2016 03:29 AM, Tony Lindgren wrote:
> * Suman Anna <s-anna@ti.com> [160107 13:26]:
>> On 01/06/2016 11:17 PM, Kishon Vijay Abraham I wrote:
>>> Hi,
>>
>> + Tero, Tony and linux-omap
>>
>>>
>>> On Thursday 07 January 2016 03:15 AM, Richard Cochran wrote:
>>>>
>>>> The dra7xx-evm box freezes hard at the very first PCI bus access, the
>>>> call to in dra7xx_pcie_readl() in dra7xx_pcie_probe().
>>>>
>>>> The out-of-tree 3.14.53 TI driver performs a reset via platform data,
>>>> calling omap_device_assert_hardreset() by hook and crook.
>>
>> Yeah, this is the only feasible way and not break multi-arch atm until a
>> reset framework is in place. We have couple of drivers (omap_iommu and
>> wkup_m3_rproc) following this approach.
> 
> Sounds like doing reset with platform data is the way to go until the
> reset controller works.

All right. I'll post the patch to do reset using platform data.

Thanks
Kishon

Re: dra7xx pci driver broken on dra7xx-evm

[Richard Cochran]

On Fri, Jan 08, 2016 at 11:37:09AM +0530, Kishon Vijay Abraham I wrote:
> All right. I'll post the patch to do reset using platform data.

Thanks for taking care of this.

BTW, I am trying to get a new board working.  Are there any *other*
dra7xx peripherals I should know about, or is the mainline stuff all
working?

Thanks,
Richard

Re: dra7xx pci driver broken on dra7xx-evm

[Kishon Vijay Abraham I]

Hi,

On Friday 08 January 2016 02:52 PM, Richard Cochran wrote:
> On Fri, Jan 08, 2016 at 11:37:09AM +0530, Kishon Vijay Abraham I wrote:
>> All right. I'll post the patch to do reset using platform data.
> 
> Thanks for taking care of this.
> 
> BTW, I am trying to get a new board working.  Are there any *other*
> dra7xx peripherals I should know about, or is the mainline stuff all
> working?

Nothing that I'm aware of. I've tested Ethernet, USB, SATA, MMC and PCIe (with
reset changes) myself. PCI was the only device that needed out of tree patches.

Thanks
Kishon