[PATCH v2 2/2] PCI: keystone: update to support multiple pci ports
m-karicheri2 at ti.com
Tue Sep 9 14:51:07 PDT 2014
On 09/09/2014 05:49 PM, Murali Karicheri wrote:
> On 09/09/2014 05:09 PM, Arnd Bergmann wrote:
>> On Tuesday 09 September 2014 16:42:46 Murali Karicheri wrote:
>>>>> /* update the Vendor ID */
>>>>> - vendor_device_id = readl(ks_pcie->va_reg_pciid);
>>>>> - writew((vendor_device_id>> 16), pp->dbi_base + PCI_DEVICE_ID);
>>>>> + writew(ks_pcie->device_id, pp->dbi_base + PCI_DEVICE_ID);
>>>>> /* update the DEV_STAT_CTRL to publish right mrrs */
>>>>> val = readl(pp->dbi_base + PCIE_CAP_BASE + PCI_EXP_DEVCTL);
>>>> This change must have slipped in accidentally, at least it's not
>>>> described in the changelog. Should this be another patch?
>>>> The change seems useful.
>>> Are you referring to mrrs or update to device id? device id is in a SoC
>>> register at index2 and is read and updated by the driver here. MRRS
>>> update was originally in the code.
>> I meant the device id change. Maybe you accidentally did 'git commit
>> --amend' during a rebase and that replaced the real changelog with
>> the one of the patch in front of it and merged the two patches?
> Actually this is an inteded. The vendor ID is in a register indicated by
> reg offset and as per the device spec, it needs to be read and updated
> by the software. Now since multiple instances of PCI device needs to be
> read the same register, the reading happens in the probe() and same is
> unmapped after that.
> + ks_pcie->device_id = readl(reg_p) >> 16;
> + devm_iounmap(dev, reg_p);
> + devm_release_mem_region(dev, res->start, resource_size(res));
> Afetr that in ks_pcie_host_init(), it update the device_id in the RC's
> config space.
BTW, I will update the commit log with more description to indicate the
above and re-send it if this is fine.
>> That happened to me a few times and would explain the strange mix
>> of two changes.
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