[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <CAE=gft75ej6bn4Z23b1+=9rjy9HfThkJagN20Jw9wZdhRWbfaw@mail.gmail.com>
Date: Mon, 10 Dec 2018 08:29:44 -0800
From: Evan Green <evgreen@...omium.org>
To: kishon@...com
Cc: vivek.gautam@...eaurora.org, robh@...nel.org,
Andy Gross <andy.gross@...aro.org>,
Doug Anderson <dianders@...omium.org>, swboyd@...omium.org,
cang@...eaurora.org, linux-kernel@...r.kernel.org,
Manu Gautam <mgautam@...eaurora.org>
Subject: Re: [PATCH v6 2/5] phy: qcom-qmp: Utilize fully-specified DT registers
On Fri, Dec 7, 2018 at 7:52 PM Kishon Vijay Abraham I <kishon@...com> wrote:
>
> Hi,
>
> On 07/12/18 2:16 PM, Vivek Gautam wrote:
> > On Fri, Dec 7, 2018 at 5:06 AM Evan Green <evgreen@...omium.org> wrote:
> >>
> >> Utilize the newly fixed up DT bindings to get the tx2 and rx2 register
> >> regions for the second lane of dual-lane PHYs. Before this change,
> >> the driver was simply using lane one's register region and adding
> >> 0x400, which reached well beyond the DT-specified register
> >> allocation. This would have been a crash were it not for the page size
> >> on ARM64. Fix the driver not to rely on the magic of virtual memory by
> >> using the newly specified DT register regions for tx2 and rx2.
> >>
> >> In order to support existing device trees, this change also contains a
> >> fallback mode for when those new register regions don't exist, which
> >> reverts to the original behavior of overreaching and prints a complaint.
> >>
> >> Signed-off-by: Evan Green <evgreen@...omium.org>
> >> Reviewed-by: Douglas Anderson <dianders@...omium.org>
> >> ---
> >> As Doug mentioned, this should land before the dts patches land, otherwise
> >> the old driver code will use the tx2 register region as pcs_misc.
> >>
> >> Changes in v6: None
> >> Changes in v5: None
> >> Changes in v4: None
> >> Changes in v3: None
> >> Changes in v2: None
> >>
> >> drivers/phy/qualcomm/phy-qcom-qmp.c | 51 +++++++++++++++++++++--------
> >> 1 file changed, 38 insertions(+), 13 deletions(-)
> >>
> >> diff --git a/drivers/phy/qualcomm/phy-qcom-qmp.c b/drivers/phy/qualcomm/phy-qcom-qmp.c
> >> index 514db7248a5d0..8204d55e2d650 100644
> >> --- a/drivers/phy/qualcomm/phy-qcom-qmp.c
> >> +++ b/drivers/phy/qualcomm/phy-qcom-qmp.c
> >> @@ -72,6 +72,9 @@
> >>
> >> #define MAX_PROP_NAME 32
> >>
> >> +/* Define the assumed distance between lanes for underspecified device trees. */
> >> +#define QMP_PHY_LEGACY_LANE_STRIDE 0x400
> >> +
> >> struct qmp_phy_init_tbl {
> >> unsigned int offset;
> >> unsigned int val;
> >> @@ -733,9 +736,6 @@ struct qmp_phy_cfg {
> >> bool has_phy_dp_com_ctrl;
> >> /* true, if PHY has secondary tx/rx lanes to be configured */
> >> bool is_dual_lane_phy;
> >> - /* Register offset of secondary tx/rx lanes for USB DP combo PHY */
> >> - unsigned int tx_b_lane_offset;
> >> - unsigned int rx_b_lane_offset;
> >>
> >> /* true, if PCS block has no separate SW_RESET register */
> >> bool no_pcs_sw_reset;
> >> @@ -748,6 +748,8 @@ struct qmp_phy_cfg {
> >> * @tx: iomapped memory space for lane's tx
> >> * @rx: iomapped memory space for lane's rx
> >> * @pcs: iomapped memory space for lane's pcs
> >> + * @tx2: iomapped memory space for second lane's tx (in dual lane PHYs)
> >> + * @rx2: iomapped memory space for second lane's rx (in dual lane PHYs)
> >> * @pcs_misc: iomapped memory space for lane's pcs_misc
> >> * @pipe_clk: pipe lock
> >> * @index: lane index
> >> @@ -759,6 +761,8 @@ struct qmp_phy {
> >> void __iomem *tx;
> >> void __iomem *rx;
> >> void __iomem *pcs;
> >> + void __iomem *tx2;
> >> + void __iomem *rx2;
> >> void __iomem *pcs_misc;
> >> struct clk *pipe_clk;
> >> unsigned int index;
> >> @@ -975,8 +979,6 @@ static const struct qmp_phy_cfg qmp_v3_usb3phy_cfg = {
> >>
> >> .has_phy_dp_com_ctrl = true,
> >> .is_dual_lane_phy = true,
> >> - .tx_b_lane_offset = 0x400,
> >> - .rx_b_lane_offset = 0x400,
> >> };
> >>
> >> static const struct qmp_phy_cfg qmp_v3_usb3_uniphy_cfg = {
> >> @@ -1031,9 +1033,6 @@ static const struct qmp_phy_cfg sdm845_ufsphy_cfg = {
> >> .mask_pcs_ready = PCS_READY,
> >>
> >> .is_dual_lane_phy = true,
> >> - .tx_b_lane_offset = 0x400,
> >> - .rx_b_lane_offset = 0x400,
> >> -
> >> .no_pcs_sw_reset = true,
> >> };
> >>
> >> @@ -1238,12 +1237,12 @@ static int qcom_qmp_phy_init(struct phy *phy)
> >> qcom_qmp_phy_configure(tx, cfg->regs, cfg->tx_tbl, cfg->tx_tbl_num);
> >> /* Configuration for other LANE for USB-DP combo PHY */
> >> if (cfg->is_dual_lane_phy)
> >> - qcom_qmp_phy_configure(tx + cfg->tx_b_lane_offset, cfg->regs,
> >> + qcom_qmp_phy_configure(qphy->tx2, cfg->regs,
> >> cfg->tx_tbl, cfg->tx_tbl_num);
> >>
> >> qcom_qmp_phy_configure(rx, cfg->regs, cfg->rx_tbl, cfg->rx_tbl_num);
> >> if (cfg->is_dual_lane_phy)
> >> - qcom_qmp_phy_configure(rx + cfg->rx_b_lane_offset, cfg->regs,
> >> + qcom_qmp_phy_configure(qphy->rx2, cfg->regs,
> >> cfg->rx_tbl, cfg->rx_tbl_num);
> >>
> >> qcom_qmp_phy_configure(pcs, cfg->regs, cfg->pcs_tbl, cfg->pcs_tbl_num);
> >> @@ -1615,8 +1614,9 @@ int qcom_qmp_phy_create(struct device *dev, struct device_node *np, int id)
> >>
> >> /*
> >> * Get memory resources for each phy lane:
> >> - * Resources are indexed as: tx -> 0; rx -> 1; pcs -> 2; and
> >> - * pcs_misc (optional) -> 3.
> >> + * Resources are indexed as: tx -> 0; rx -> 1; pcs -> 2.
> >> + * For dual lane PHYs: tx2 -> 3, rx2 -> 4, pcs_misc (optional) -> 5
> >> + * For single lane PHYs: pcs_misc (optional) -> 3.
> >> */
> >> qphy->tx = of_iomap(np, 0);
> >> if (!qphy->tx)
> >> @@ -1630,7 +1630,32 @@ int qcom_qmp_phy_create(struct device *dev, struct device_node *np, int id)
> >> if (!qphy->pcs)
> >> return -ENOMEM;
> >>
> >> - qphy->pcs_misc = of_iomap(np, 3);
> >> + /*
> >> + * If this is a dual-lane PHY, then there should be registers for the
> >> + * second lane. Some old device trees did not specify this, so fall
> >> + * back to old legacy behavior of assuming they can be reached at an
> >> + * offset from the first lane.
> >> + */
> >> + if (qmp->cfg->is_dual_lane_phy) {
> >> + qphy->tx2 = of_iomap(np, 3);
> >> + qphy->rx2 = of_iomap(np, 4);
> >> + if (!qphy->tx2 || !qphy->rx2) {
> >> + dev_warn(dev,
> >> + "Underspecified device tree, falling back to legacy register regions\n");
> >> +
> >> + /* In the old version, pcs_misc is at index 3. */
> >> + qphy->pcs_misc = qphy->tx2;
> >> + qphy->tx2 = qphy->tx + QMP_PHY_LEGACY_LANE_STRIDE;
> >> + qphy->rx2 = qphy->rx + QMP_PHY_LEGACY_LANE_STRIDE;
> >> +
> >> + } else {
> >> + qphy->pcs_misc = of_iomap(np, 5);
> >> + }
> >> +
> >> + } else {
> >> + qphy->pcs_misc = of_iomap(np, 3);
> >> + }
> >> +
> >> if (!qphy->pcs_misc)
> >> dev_vdbg(dev, "PHY pcs_misc-reg not used\n");
> >>
> >> --
> >> 2.18.1
> >>
> >
> > Tested on db820c [1]. USB, PCIe come up.
> > Tested-by: Vivek Gautam <vivek.gautam@...eaurora.org>
> >
> > [1] https://github.com/vivekgautam1/linux/tree/origin/v4.20-rc5/db820c
>
> Thank you Vivek.
> Evan, can you resend this series after rebasing to phy -next and also your
> other series?
Sure. The other series you're referring to is the #clock-cells one
here [1] I assume? I will resend both on top of phy-next.
-Evan
[1] https://lkml.org/lkml/2018/11/30/214
Powered by blists - more mailing lists