Re: [PATCH v2] phy: cadence: Sierra: Add support for skipping configuration

From: Vinod Koul
Date: Wed Feb 02 2022 - 09:23:40 EST


On 28-01-22, 12:56, Aswath Govindraju wrote:
> In some cases, a single SerDes instance can be shared between two different
> processors, each using a separate link. In these cases, the SerDes
> configuration is done in an earlier boot stage. Therefore, add support to
> skip reconfiguring, if it is was already configured beforehand.

This fails to apply, pls rebase and resend

>
> Signed-off-by: Aswath Govindraju <a-govindraju@xxxxxx>
> ---
>
> Changes since v1:
> - Removed redundant braces
> - Corrected the logic for skipping multilink configuration
> - Corrected the order in failure path
>
> drivers/phy/cadence/phy-cadence-sierra.c | 82 ++++++++++++++++--------
> 1 file changed, 57 insertions(+), 25 deletions(-)
>
> diff --git a/drivers/phy/cadence/phy-cadence-sierra.c b/drivers/phy/cadence/phy-cadence-sierra.c
> index e265647e29a2..6b917f7bddbe 100644
> --- a/drivers/phy/cadence/phy-cadence-sierra.c
> +++ b/drivers/phy/cadence/phy-cadence-sierra.c
> @@ -370,6 +370,7 @@ struct cdns_sierra_phy {
> int nsubnodes;
> u32 num_lanes;
> bool autoconf;
> + int already_configured;
> struct clk_onecell_data clk_data;
> struct clk *output_clks[CDNS_SIERRA_OUTPUT_CLOCKS];
> };
> @@ -517,7 +518,7 @@ static int cdns_sierra_phy_init(struct phy *gphy)
> int i, j;
>
> /* Initialise the PHY registers, unless auto configured */
> - if (phy->autoconf || phy->nsubnodes > 1)
> + if (phy->autoconf || phy->already_configured || phy->nsubnodes > 1)
> return 0;
>
> clk_set_rate(phy->input_clks[CMN_REFCLK_DIG_DIV], 25000000);
> @@ -646,6 +647,18 @@ static const struct phy_ops ops = {
> .owner = THIS_MODULE,
> };
>
> +static int cdns_sierra_noop_phy_on(struct phy *gphy)
> +{
> + usleep_range(5000, 10000);
> +
> + return 0;
> +}
> +
> +static const struct phy_ops noop_ops = {
> + .power_on = cdns_sierra_noop_phy_on,
> + .owner = THIS_MODULE,
> +};
> +
> static u8 cdns_sierra_pll_mux_get_parent(struct clk_hw *hw)
> {
> struct cdns_sierra_pll_mux *mux = to_cdns_sierra_pll_mux(hw);
> @@ -1118,13 +1131,6 @@ static int cdns_sierra_phy_get_clocks(struct cdns_sierra_phy *sp,
> struct clk *clk;
> int ret;
>
> - clk = devm_clk_get_optional(dev, "phy_clk");
> - if (IS_ERR(clk)) {
> - dev_err(dev, "failed to get clock phy_clk\n");
> - return PTR_ERR(clk);
> - }
> - sp->input_clks[PHY_CLK] = clk;
> -
> clk = devm_clk_get_optional(dev, "cmn_refclk_dig_div");
> if (IS_ERR(clk)) {
> dev_err(dev, "cmn_refclk_dig_div clock not found\n");
> @@ -1160,17 +1166,33 @@ static int cdns_sierra_phy_get_clocks(struct cdns_sierra_phy *sp,
> return 0;
> }
>
> -static int cdns_sierra_phy_enable_clocks(struct cdns_sierra_phy *sp)
> +static int cdns_sierra_phy_clk(struct cdns_sierra_phy *sp)
> {
> + struct device *dev = sp->dev;
> + struct clk *clk;
> int ret;
>
> + clk = devm_clk_get_optional(dev, "phy_clk");
> + if (IS_ERR(clk)) {
> + dev_err(dev, "failed to get clock phy_clk\n");
> + return PTR_ERR(clk);
> + }
> + sp->input_clks[PHY_CLK] = clk;
> +
> ret = clk_prepare_enable(sp->input_clks[PHY_CLK]);
> if (ret)
> return ret;
>
> + return 0;
> +}
> +
> +static int cdns_sierra_phy_enable_clocks(struct cdns_sierra_phy *sp)
> +{
> + int ret;
> +
> ret = clk_prepare_enable(sp->output_clks[CDNS_SIERRA_PLL_CMNLC]);
> if (ret)
> - goto err_pll_cmnlc;
> + return ret;
>
> ret = clk_prepare_enable(sp->output_clks[CDNS_SIERRA_PLL_CMNLC1]);
> if (ret)
> @@ -1181,9 +1203,6 @@ static int cdns_sierra_phy_enable_clocks(struct cdns_sierra_phy *sp)
> err_pll_cmnlc1:
> clk_disable_unprepare(sp->output_clks[CDNS_SIERRA_PLL_CMNLC]);
>
> -err_pll_cmnlc:
> - clk_disable_unprepare(sp->input_clks[PHY_CLK]);
> -
> return ret;
> }
>
> @@ -1191,7 +1210,8 @@ static void cdns_sierra_phy_disable_clocks(struct cdns_sierra_phy *sp)
> {
> clk_disable_unprepare(sp->output_clks[CDNS_SIERRA_PLL_CMNLC1]);
> clk_disable_unprepare(sp->output_clks[CDNS_SIERRA_PLL_CMNLC]);
> - clk_disable_unprepare(sp->input_clks[PHY_CLK]);
> + if (!sp->already_configured)
> + clk_disable_unprepare(sp->input_clks[PHY_CLK]);
> }
>
> static int cdns_sierra_phy_get_resets(struct cdns_sierra_phy *sp,
> @@ -1382,22 +1402,30 @@ static int cdns_sierra_phy_probe(struct platform_device *pdev)
> if (ret)
> return ret;
>
> - ret = cdns_sierra_phy_get_resets(sp, dev);
> - if (ret)
> - goto unregister_clk;
> -
> ret = cdns_sierra_phy_enable_clocks(sp);
> if (ret)
> goto unregister_clk;
>
> - /* Enable APB */
> - reset_control_deassert(sp->apb_rst);
> + regmap_field_read(sp->pma_cmn_ready, &sp->already_configured);
> +
> + if (!sp->already_configured) {
> + ret = cdns_sierra_phy_clk(sp);
> + if (ret)
> + goto clk_disable;
> +
> + ret = cdns_sierra_phy_get_resets(sp, dev);
> + if (ret)
> + goto clk_disable;
> +
> + /* Enable APB */
> + reset_control_deassert(sp->apb_rst);
> + }
>
> /* Check that PHY is present */
> regmap_field_read(sp->macro_id_type, &id_value);
> if (sp->init_data->id_value != id_value) {
> ret = -EINVAL;
> - goto clk_disable;
> + goto ctrl_assert;
> }
>
> sp->autoconf = of_property_read_bool(dn, "cdns,autoconf");
> @@ -1433,8 +1461,10 @@ static int cdns_sierra_phy_probe(struct platform_device *pdev)
>
> sp->num_lanes += sp->phys[node].num_lanes;
>
> - gphy = devm_phy_create(dev, child, &ops);
> -
> + if (!sp->already_configured)
> + gphy = devm_phy_create(dev, child, &ops);
> + else
> + gphy = devm_phy_create(dev, child, &noop_ops);
> if (IS_ERR(gphy)) {
> ret = PTR_ERR(gphy);
> of_node_put(child);
> @@ -1455,7 +1485,7 @@ static int cdns_sierra_phy_probe(struct platform_device *pdev)
> }
>
> /* If more than one subnode, configure the PHY as multilink */
> - if (!sp->autoconf && sp->nsubnodes > 1) {
> + if (!sp->already_configured && !sp->autoconf && sp->nsubnodes > 1) {
> ret = cdns_sierra_phy_configure_multilink(sp);
> if (ret)
> goto put_control;
> @@ -1473,9 +1503,11 @@ static int cdns_sierra_phy_probe(struct platform_device *pdev)
> put_control:
> while (--node >= 0)
> reset_control_put(sp->phys[node].lnk_rst);
> +ctrl_assert:
> + if (!sp->already_configured)
> + reset_control_assert(sp->apb_rst);
> clk_disable:
> cdns_sierra_phy_disable_clocks(sp);
> - reset_control_assert(sp->apb_rst);
> unregister_clk:
> cdns_sierra_clk_unregister(sp);
> return ret;
> --
> 2.17.1

--
~Vinod