Re: [PATCH v2 4/4] PCI: cadence: Fix to read 32-bit Vendor ID/Device ID property from DT

[Kishon Vijay Abraham I]

Hi Lorenzo,

On 5/1/2020 8:41 PM, Lorenzo Pieralisi wrote:
> On Fri, Apr 17, 2020 at 05:13:22PM +0530, Kishon Vijay Abraham I wrote:
>> The PCI Bus Binding specification (IEEE Std 1275-1994 Revision 2.1 [1])
>> defines both Vendor ID and Device ID to be 32-bits. Fix
>> pcie-cadence-host.c driver to read 32-bit Vendor ID and Device ID
>> properties from device tree.
>>
>> [1] -> https://www.devicetree.org/open-firmware/bindings/pci/pci2_1.pdf
>>
>> Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
>> ---
>>  drivers/pci/controller/cadence/pcie-cadence-host.c | 4 ++--
>>  drivers/pci/controller/cadence/pcie-cadence.h      | 4 ++--
>>  2 files changed, 4 insertions(+), 4 deletions(-)
> 
> I don't see how you would use a 32-bit value for a 16-bit register so
> certainly the struct cdns_pcie_rc fields size is questionable anyway.
> 
> I *assume* you are referring to 4.1.2.1 and the property list
> encoded as "encode-int".
> 
> I would like to get RobH's opinion on this - I don't know myself
> whether the PCI OF bindings you added are still relevant and how
> they should be interpreted.

This change was made due to RobH's comment below [1]

[1] ->
https://lore.kernel.org/r/CAL_JsqLYScxGySy8xaN-UB6URfw8K_jSiuSXwVoTU9-RdJecww@xxxxxxxxxxxxxx/

Thanks
Kishon

> 
> Thanks
> Lorenzo
> 
>> diff --git a/drivers/pci/controller/cadence/pcie-cadence-host.c b/drivers/pci/controller/cadence/pcie-cadence-host.c
>> index 8f72967f298f..31e67c9c88cf 100644
>> --- a/drivers/pci/controller/cadence/pcie-cadence-host.c
>> +++ b/drivers/pci/controller/cadence/pcie-cadence-host.c
>> @@ -229,10 +229,10 @@ int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
>>  	}
>>  
>>  	rc->vendor_id = 0xffff;
>> -	of_property_read_u16(np, "vendor-id", &rc->vendor_id);
>> +	of_property_read_u32(np, "vendor-id", &rc->vendor_id);
>>  
>>  	rc->device_id = 0xffff;
>> -	of_property_read_u16(np, "device-id", &rc->device_id);
>> +	of_property_read_u32(np, "device-id", &rc->device_id);
>>  
>>  	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "reg");
>>  	pcie->reg_base = devm_ioremap_resource(dev, res);
>> diff --git a/drivers/pci/controller/cadence/pcie-cadence.h b/drivers/pci/controller/cadence/pcie-cadence.h
>> index 6bd89a21bb1c..df14ad002fe9 100644
>> --- a/drivers/pci/controller/cadence/pcie-cadence.h
>> +++ b/drivers/pci/controller/cadence/pcie-cadence.h
>> @@ -262,8 +262,8 @@ struct cdns_pcie_rc {
>>  	struct resource		*bus_range;
>>  	void __iomem		*cfg_base;
>>  	u32			no_bar_nbits;
>> -	u16			vendor_id;
>> -	u16			device_id;
>> +	u32			vendor_id;
>> +	u32			device_id;
>>  };
>>  
>>  /**
>> -- 
>> 2.17.1
>>