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Date:   Tue, 15 Dec 2020 14:25:04 +0100
From:   Mian Yousaf Kaukab <ykaukab@suse.de>
To:     Vidya Sagar <vidyas@nvidia.com>
Cc:     lorenzo.pieralisi@arm.com, robh@kernel.org, bhelgaas@google.com,
        linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: dwc: tegra194: issue with card containing a bridge
Message-ID: <20201215132504.GA20914@suse.de>
References: <20201215102442.GA20517@suse.de>
 <9a8abc90-cf18-b0c8-3bcb-efbe03f0ca4c@nvidia.com>
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On Tue, Dec 15, 2020 at 05:45:59PM +0530, Vidya Sagar wrote:
> Thanks Mian for bringing it to our notice.
> Have you tried removing the dw_pcie_setup_rc(pp); call from pcie-tegra194.c
> file on top of linux-next? and does that solve the issue?
> 
> diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c
> b/drivers/pci/controller/dwc/pcie-tegra194.c
> index 5597b2a49598..1c9e9c054592 100644
> --- a/drivers/pci/controller/dwc/pcie-tegra194.c
> +++ b/drivers/pci/controller/dwc/pcie-tegra194.c
> @@ -907,7 +907,7 @@ static void tegra_pcie_prepare_host(struct pcie_port
> *pp)
>                 dw_pcie_writel_dbi(pci, CFG_TIMER_CTRL_MAX_FUNC_NUM_OFF,
> val);
>         }
> 
> -       dw_pcie_setup_rc(pp);
> +       //dw_pcie_setup_rc(pp);
I still see the same issue with this change.
Reverting b9ac0f9dc8ea works though.
> 
>         clk_set_rate(pcie->core_clk, GEN4_CORE_CLK_FREQ);
> 
> I took a quick look at the dw_pcie_setup_rc() implementation and I'm not
> sure why calling it second time should create any issue for the enumeration
> of devices behind a switch. Perhaps I need to spend more time to debug that
> part.
> In any case, since dw_pcie_setup_rc() is already part of
> dw_pcie_host_init(), I think it can be removed from
> tegra_pcie_prepare_host() implemention.
> 
> Thanks,
> Vidya Sagar
> 
BR,
Yousaf