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Message-ID: <6e40c4ee-e549-4b41-8a12-65b474b8ef24@ti.com>
Date:   Wed, 25 Oct 2023 16:28:23 +0530
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CC:     Bjorn Helgaas <helgaas@kernel.org>,
        Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>,
        <bhelgaas@google.com>, <lpieralisi@kernel.org>, <robh@kernel.org>,
        <kw@linux.com>, <linux-pci@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>,
        <linux-arm-kernel@lists.infradead.org>, <r-gunasekaran@ti.com>,
        <srk@ti.com>, <s-vadapalli@ti.com>
Subject: Re: [PATCH v3] PCI: keystone: Fix pci_ops for AM654x SoC
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To:     Serge Semin <fancer.lancer@gmail.com>
References: <20231023212628.GA1627567@bhelgaas>
 <c7851172-f474-42f3-9730-1f323f9e6c73@ti.com>
 <3szgydgz7ege5h75mwdket5lniwy4oe52dq2uqehf74il5hc5j@oaqcbmfuf6de>
From:   Siddharth Vadapalli <s-vadapalli@ti.com>
In-Reply-To: <3szgydgz7ege5h75mwdket5lniwy4oe52dq2uqehf74il5hc5j@oaqcbmfuf6de>
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Serge,

On 25/10/23 15:58, Serge Semin wrote:
> Hi Siddharth, Bjorn
> 
> On Wed, Oct 25, 2023 at 10:32:50AM +0530, Siddharth Vadapalli wrote:

...

>>
> 
>> ks_pcie_probe()
>>     dw_pcie_host_init()
>>         pci_host_probe()
>>     ks_pcie_v3_65_add_bus()
> 
> I guess what Bjorn implied was to add the ks_pcie_v3_65_add_bus()
> invocation to the host_init() callback, i.e. in ks_pcie_host_init().

I misunderstood the term "host_init()", and interpret it as
"dw_pcie_host_init()", due to which I thought I will add it after
dw_pcie_host_init() invocation in ks_pcie_probe. Thank you for clarifying.

> Moreover initializing the BARs/MSI after all the PCIe hierarchy has
> been probed will eventually cause problems since MSI's won't work
> until the ks_pcie_v3_65_add_bus() is called.
> 
>>
>> Since the .add_bus() method will be removed following this change, I suppose
>> that the patch I post for it can be applied instead of this v3 patch which fixes
>> pci_ops.
>>
> 
>> The patch I plan to post as a replacement for the current patch which shall also
>> remove the ks_pcie_v3_65_add_bus() and the .add_bus() method is:
> 
> Just a note. Seeing the Bjorn's suggestion may cause a regression on
> the Keystone PCIe Host v3.65 I would suggest to merge in the original
> fix as is and post an additional cleanup patch, like below with proper
> modifications, on top of it. Thus we'll minimize a risk to break
> things at least on the stable kernels.

I will post it as a separate cleanup patch in that case and this v3 patch can be
merged independently as you suggested.

-- 
Regards,
Siddharth.