[PATCH v3 6/9] phy: qcom-qmp-pcie: support separate tables for EP mode

[Dmitry Baryshkov <dmitry.baryshkov@linaro.org>]

The PCIe QMP PHY requires different programming sequences when being
used for the RC (Root Complex) or for the EP (End Point) modes. Allow
selecting the submode and thus selecting a set of PHY programming
tables.

Since the RC and EP modes share common some common init sequence, the
common sequence is kept in the main table and the sequence differences
are pushed to the secondary tables.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/phy/qualcomm/phy-qcom-qmp-pcie.c | 54 ++++++++++++++++++++----
 1 file changed, 46 insertions(+), 8 deletions(-)

diff --git a/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c b/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c
index d115f7ef3901..d945e8c61811 100644
--- a/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c
+++ b/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c
@@ -1369,10 +1369,14 @@ struct qmp_phy_cfg {
 	/* Main init sequence for PHY blocks - serdes, tx, rx, pcs */
 	struct qmp_phy_cfg_tables main;
 	/*
-	 * Additional init sequence for PHY blocks, providing additional
-	 * register programming. Unless required it can be left omitted.
+	 * Additional init sequences for PHY blocks, providing additional
+	 * register programming. They are used for providing separate sequences
+	 * for the Root Complex and for the End Point usecases.
+	 *
+	 * If EP mode is not supported, both tables can be left empty.
 	 */
-	struct qmp_phy_cfg_tables *secondary;
+	struct qmp_phy_cfg_tables *secondary_rc; /* for the RC only */
+	struct qmp_phy_cfg_tables *secondary_ep; /* for the EP only */
 
 	/* clock ids to be requested */
 	const char * const *clk_list;
@@ -1422,6 +1426,7 @@ struct qmp_phy_cfg {
  * @index: lane index
  * @qmp: QMP phy to which this lane belongs
  * @mode: current PHY mode
+ * @secondary: currently selected PHY secondary init table set
  */
 struct qmp_phy {
 	struct phy *phy;
@@ -1434,6 +1439,7 @@ struct qmp_phy {
 	void __iomem *rx2;
 	void __iomem *pcs_misc;
 	struct clk *pipe_clk;
+	const struct qmp_phy_cfg_tables *secondary;
 	unsigned int index;
 	struct qcom_qmp *qmp;
 	enum phy_mode mode;
@@ -1687,7 +1693,15 @@ static const struct qmp_phy_cfg sm8250_qmp_gen3x1_pciephy_cfg = {
 	.pcs_misc_tbl		= sm8250_qmp_pcie_pcs_misc_tbl,
 	.pcs_misc_tbl_num	= ARRAY_SIZE(sm8250_qmp_pcie_pcs_misc_tbl),
 	},
-	.secondary = &(struct qmp_phy_cfg_tables) {
+	/*
+	 * For sm8250 the split between the primary and secondary_rc tables is
+	 * historical, it reflects the programming sequence common to all PCIe
+	 * PHYs on this platform and a sequence required for this particular
+	 * PHY type. If EP support for sm8250 is required, the
+	 * primary/secondary_rc split is to be reconsidered and adjusted
+	 * according to EP programming sequence.
+	 */
+	.secondary_rc = &(struct qmp_phy_cfg_tables) {
 	.serdes_tbl		= sm8250_qmp_gen3x1_pcie_serdes_tbl,
 	.serdes_tbl_num		= ARRAY_SIZE(sm8250_qmp_gen3x1_pcie_serdes_tbl),
 	.rx_tbl			= sm8250_qmp_gen3x1_pcie_rx_tbl,
@@ -1730,7 +1744,15 @@ static const struct qmp_phy_cfg sm8250_qmp_gen3x2_pciephy_cfg = {
 	.pcs_misc_tbl		= sm8250_qmp_pcie_pcs_misc_tbl,
 	.pcs_misc_tbl_num	= ARRAY_SIZE(sm8250_qmp_pcie_pcs_misc_tbl),
 	},
-	.secondary = &(struct qmp_phy_cfg_tables) {
+	/*
+	 * For sm8250 the split between the primary and secondary_rc tables is
+	 * historical, it reflects the programming sequence common to all PCIe
+	 * PHYs on this platform and a sequence required for this particular
+	 * PHY type. If EP support for sm8250 is required, the
+	 * primary/secondary_rc split is to be reconsidered and adjusted
+	 * according to EP programming sequence.
+	 */
+	.secondary_rc = &(struct qmp_phy_cfg_tables) {
 	.tx_tbl			= sm8250_qmp_gen3x2_pcie_tx_tbl,
 	.tx_tbl_num		= ARRAY_SIZE(sm8250_qmp_gen3x2_pcie_tx_tbl),
 	.rx_tbl			= sm8250_qmp_gen3x2_pcie_rx_tbl,
@@ -2085,8 +2107,12 @@ static int qcom_qmp_phy_pcie_power_on(struct phy *phy)
 	unsigned int mask, val, ready;
 	int ret;
 
+	/* Default to RC mode if the mode was not selected using phy_set_mode_ext() */
+	if (!qphy->secondary)
+		qphy->secondary = cfg->secondary_rc;
+
 	qcom_qmp_phy_pcie_serdes_init(qphy, &cfg->main);
-	qcom_qmp_phy_pcie_serdes_init(qphy, cfg->secondary);
+	qcom_qmp_phy_pcie_serdes_init(qphy, qphy->secondary);
 
 	ret = clk_prepare_enable(qphy->pipe_clk);
 	if (ret) {
@@ -2096,10 +2122,10 @@ static int qcom_qmp_phy_pcie_power_on(struct phy *phy)
 
 	/* Tx, Rx, and PCS configurations */
 	qcom_qmp_phy_pcie_lanes_init(qphy, &cfg->main);
-	qcom_qmp_phy_pcie_lanes_init(qphy, cfg->secondary);
+	qcom_qmp_phy_pcie_lanes_init(qphy, qphy->secondary);
 
 	qcom_qmp_phy_pcie_pcs_init(qphy, &cfg->main);
-	qcom_qmp_phy_pcie_pcs_init(qphy, cfg->secondary);
+	qcom_qmp_phy_pcie_pcs_init(qphy, qphy->secondary);
 
 	/*
 	 * Pull out PHY from POWER DOWN state.
@@ -2201,6 +2227,18 @@ static int qcom_qmp_phy_pcie_set_mode(struct phy *phy,
 
 	qphy->mode = mode;
 
+	switch (submode) {
+	case PHY_SUBMODE_PCIE_RC:
+		qphy->secondary = qphy->cfg->secondary_rc;
+		break;
+	case PHY_SUBMODE_PCIE_EP:
+		qphy->secondary = qphy->cfg->secondary_ep;
+		break;
+	default:
+		dev_err(&phy->dev, "Unuspported submode %d\n", submode);
+		return -EINVAL;
+	}
+
 	return 0;
 }
 
-- 
2.35.1