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From: Bjorn Helgaas <helgaas@kernel.org>
To: Murali Karicheri <m-karicheri2@ti.com>
Cc: linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org
Subject: ks_dw_pcie_initiate_link_train() question
Date: Tue, 4 Oct 2016 12:40:51 -0500	[thread overview]
Message-ID: <20161004174051.GE3449@localhost> (raw)

Hi Murali,

This code looks suspicious.  Can you comment?

    void ks_dw_pcie_initiate_link_train(struct keystone_pcie *ks_pcie)
    {
        u32 val;

        /* Disable Link training */
        val = readl(ks_pcie->va_app_base + CMD_STATUS);
        val &= ~LTSSM_EN_VAL;
        writel(LTSSM_EN_VAL | val,  ks_pcie->va_app_base + CMD_STATUS);

Here we cleared the LTSSM_EN_VAL bit in "val", but then we add it
right back in before writing it back to CMD_STATUS.

That looks like a cut and paste error to me, but of course I don't
know the hardware.

        /* Initiate Link Training */
        val = readl(ks_pcie->va_app_base + CMD_STATUS);
        writel(LTSSM_EN_VAL | val,  ks_pcie->va_app_base + CMD_STATUS);
    }



             reply	other threads:[~2016-10-04 17:40 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-10-04 17:40 Bjorn Helgaas [this message]
2016-10-04 21:52 ` ks_dw_pcie_initiate_link_train() question Murali Karicheri

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