On Mon, May 09, 2022 at 02:18:34PM +0200, AngeloGioacchino Del Regno wrote:
> Il 04/04/22 16:48, AngeloGioacchino Del Regno ha scritto:
> > The controller may have been left out of reset by the bootloader,
> > in which case, before the powerup sequence, the controller will be
> > found preconfigured with values that were set before booting the
> > kernel: this produces a controller failure, with the result of
> > a failure during the mtk_pcie_startup_port() sequence as the PCIe
> > link never gets up.
> >
> > To ensure that we get a clean start in an expected state, assert
> > both the PHY and MAC resets before executing the controller
> > power-up sequence.
> >
> > Fixes: d3bf75b579b9 ("PCI: mediatek-gen3: Add MediaTek Gen3 driver for MT8192")
> > Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>
>
> Friendly ping for an important fix :-)
d3bf75b579b9 appeared in v5.13-rc1 (May 2021, a year ago), so I assume
this is important for v5.19, but not urgent enough to require being in
v5.18. Right?
> > ---
> > drivers/pci/controller/pcie-mediatek-gen3.c | 8 ++++++++
> > 1 file changed, 8 insertions(+)
> >
> > diff --git a/drivers/pci/controller/pcie-mediatek-gen3.c b/drivers/pci/controller/pcie-mediatek-gen3.c
> > index f7048ea4c020..dccdfce12b1c 100644
> > --- a/drivers/pci/controller/pcie-mediatek-gen3.c
> > +++ b/drivers/pci/controller/pcie-mediatek-gen3.c
> > @@ -838,6 +838,14 @@ static int mtk_pcie_setup(struct mtk_gen3_pcie *pcie)
> > if (err)
> > return err;
> > + /*
> > + * The controller may have been left out of reset by the bootloader
> > + * so make sure that we get a clean start by asserting resets here.
> > + */
> > + reset_control_assert(pcie->phy_reset);
> > + reset_control_assert(pcie->mac_reset);
> > + usleep_range(10, 20);
> > +
> > /* Don't touch the hardware registers before power up */
> > err = mtk_pcie_power_up(pcie);
> > if (err)
>
>
>
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