Re: [PATCH 11/37] PCI: dwc: Split pcie-designware.c into host and core files

[Kishon Vijay Abraham I]

Hi Joao,

On Monday 16 January 2017 03:57 PM, Joao Pinto wrote:
> 
> Hi,
> 
> Às 5:21 AM de 1/16/2017, Kishon Vijay Abraham I escreveu:
>> Hi Joao,
>>
>> On Friday 13 January 2017 10:19 PM, Joao Pinto wrote:
>>> Às 10:26 AM de 1/12/2017, Kishon Vijay Abraham I escreveu:
>>>> Split pcie-designware.c into pcie-designware-host.c that contains
>>>> the host specific parts of the driver and pcie-designware.c that
>>>> contains the parts used by both host driver and endpoint driver.
>>>>
>>>> Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
>>>> ---
>>>>  drivers/pci/dwc/Makefile               |    2 +-
>>>>  drivers/pci/dwc/pcie-designware-host.c |  619 ++++++++++++++++++++++++++++++++
>>>>  drivers/pci/dwc/pcie-designware.c      |  613 +------------------------------
>>>>  drivers/pci/dwc/pcie-designware.h      |    8 +
>>>>  4 files changed, 634 insertions(+), 608 deletions(-)
>>>>  create mode 100644 drivers/pci/dwc/pcie-designware-host.c
>>>>
>>>> diff --git a/drivers/pci/dwc/Makefile b/drivers/pci/dwc/Makefile
>>>> index 7d27c14..3b57e55 100644
>>>> --- a/drivers/pci/dwc/Makefile
>>>> +++ b/drivers/pci/dwc/Makefile
>>>> @@ -1,4 +1,4 @@
>>>
>>> (snip...)
>>>
>>>> -static void dw_pcie_prog_outbound_atu(struct dw_pcie *pci, int index,
>>>> -				      int type, u64 cpu_addr, u64 pci_addr,
>>>> -				      u32 size)
>>>> +void dw_pcie_prog_outbound_atu(struct dw_pcie *pci, int index, int type,
>>>> +			       u64 cpu_addr, u64 pci_addr, u32 size)
>>>>  {
>>>>  	u32 retries, val;
>>>>  
>>>> @@ -186,220 +151,6 @@ static void dw_pcie_prog_outbound_atu(struct dw_pcie *pci, int index,
>>>>  	dev_err(pci->dev, "iATU is not being enabled\n");
>>>>  }
>>>
>>> Kishon, iATU only makes sense in The Root Complex (host), so it should be inside
>>> the pcie-designware-host.
>>
>> That is not true. Outbound ATU should be programmed to access host side buffers
>> and inbound ATU should be programmed for the host to access EP mem space.
> 
> Sorry, I was not clear enough. What I was trying to suggest is, since the ATU
> programming is done by the host, wouldn't be better to include it in the
> pcie-designware-host? It is just an architectural detail.

ATU programming is required in EP mode. See "[PATCH 24/37] PCI: dwc:
designware: Add EP mode support" in this patch series.

Anything that's required by both EP mode and RC mode, I've placed in
pcie-designware.c

Thanks
Kishon