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Date:   Mon, 16 May 2022 15:32:46 -0500
From:   Rob Herring <robh@kernel.org>
To:     Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc:     Jingoo Han <jingoohan1@gmail.com>,
        Gustavo Pimentel <gustavo.pimentel@synopsys.com>,
        Bjorn Helgaas <bhelgaas@google.com>,
        Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
        Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= <kw@linux.com>,
        Serge Semin <fancer.lancer@gmail.com>,
        Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>,
        Pavel Parkhomenko <Pavel.Parkhomenko@baikalelectronics.ru>,
        Frank Li <Frank.Li@nxp.com>,
        Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>,
        linux-pci@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 06/17] PCI: dwc: Add IP-core version detection
 procedure
Message-ID: <20220516203246.GD3209795-robh@kernel.org>
References: <20220503214638.1895-1-Sergey.Semin@baikalelectronics.ru>
 <20220503214638.1895-7-Sergey.Semin@baikalelectronics.ru>
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In-Reply-To: <20220503214638.1895-7-Sergey.Semin@baikalelectronics.ru>
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On Wed, May 04, 2022 at 12:46:27AM +0300, Serge Semin wrote:
> Since DWC PCIe v4.70a the controller version and version type can be read
> from the PORT_LOGIC.PCIE_VERSION_OFF and PORT_LOGIC.PCIE_VERSION_TYPE_OFF
> registers respectively. Seeing the generic code has got version-dependent
> parts let's use these registers to find out the controller version.  The
> detection procedure is executed for both RC and EP modes right after the
> platform-specific initialization. We can't do that earlier since the
> glue-drivers can perform the DBI-related setups there including the bus
> reference clocks activation, without which the CSRs just can't be read.
> 
> Note the CSRs content is zero on the older DWC PCIe controller. In that
> case we have no choice but to rely on the platform setup.
> 
> Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
> 
> ---
> 
> Changelog v2:
> - Move the IP-core version detection procedure call from
>   dw_pcie_ep_init_complete() to dw_pcie_ep_init().
> ---
>  .../pci/controller/dwc/pcie-designware-ep.c   |  2 ++
>  .../pci/controller/dwc/pcie-designware-host.c |  2 ++
>  drivers/pci/controller/dwc/pcie-designware.c  | 24 +++++++++++++++++++
>  drivers/pci/controller/dwc/pcie-designware.h  |  6 +++++
>  4 files changed, 34 insertions(+)

Reviewed-by: Rob Herring <robh@kernel.org>