[PATCH v2] phy: cadence: Sierra: Add support for skipping configuration
Aswath Govindraju
a-govindraju at ti.com
Tue Feb 1 21:31:23 PST 2022
Hi Vinod,
On 02/02/22 10:25 am, Vinod Koul wrote:
> 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.
>>
>> Signed-off-by: Aswath Govindraju <a-govindraju at ti.com>
>> ---
>>
>> 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;
>
> where is this set and is set based on..?
>
It is being set at [1] based on reading phy_cmn_ready bit field. This
gets set when the configuration is done and the PLLs are locked.
>> 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);
>> +
[1]
Thanks,
Aswath
>> + 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
>
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