--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2022 Texas Instruments Incorporated - https://www.ti.com/
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/module.h>
+#include <linux/phy/phy.h>
+#include <linux/phy/phy-mipi-dphy.h>
+#include <linux/platform_device.h>
+
+#define DPHY_PMA_CMN(reg) (reg)
+#define DPHY_PCS(reg) (0xb00 + (reg))
+#define DPHY_ISO(reg) (0xc00 + (reg))
+
+#define DPHY_CMN_SSM DPHY_PMA_CMN(0x20)
+#define DPHY_CMN_RX_MODE_EN BIT(10)
+#define DPHY_CMN_RX_BANDGAP_TIMER_MASK GENMASK(8, 1)
+#define DPHY_CMN_SSM_EN BIT(0)
+
+#define DPHY_CMN_RX_BANDGAP_TIMER 0x14
+
+#define DPHY_BAND_CFG DPHY_PCS(0x0)
+#define DPHY_BAND_CFG_RIGHT_BAND GENMASK(9, 5)
+#define DPHY_BAND_CFG_LEFT_BAND GENMASK(4, 0)
+
+#define DPHY_POWER_ISLAND_EN_DATA DPHY_PCS(0x8)
+#define DPHY_POWER_ISLAND_EN_DATA_VAL 0xaaaaaaaa
+
+#define DPHY_POWER_ISLAND_EN_CLK DPHY_PCS(0xc)
+#define DPHY_POWER_ISLAND_EN_CLK_VAL 0xaa
+
+#define DPHY_ISO_CL_CTRL_L DPHY_ISO(0x10)
+#define DPHY_ISO_DL_CTRL_L0 DPHY_ISO(0x14)
+#define DPHY_ISO_DL_CTRL_L1 DPHY_ISO(0x20)
+#define DPHY_ISO_DL_CTRL_L2 DPHY_ISO(0x30)
+#define DPHY_ISO_DL_CTRL_L3 DPHY_ISO(0x3c)
+
+#define DPHY_ISO_LANE_READY_BIT 0
+#define DPHY_ISO_LANE_READY_TIMEOUT_MS 100UL
+
+#define DPHY_LANES_MIN 1
+#define DPHY_LANES_MAX 4
+
+struct cdns_dphy_rx {
+ void __iomem *regs;
+ struct device *dev;
+ struct phy *phy;
+};
+
+struct cdns_dphy_rx_band {
+ /* Rates are in Mbps. */
+ unsigned int min_rate;
+ unsigned int max_rate;
+};
+
+/* Order of bands is important since the index is the band number. */
+static const struct cdns_dphy_rx_band bands[] = {
+ { 80, 100 }, { 100, 120 }, { 120, 160 }, { 160, 200 }, { 200, 240 },
+ { 240, 280 }, { 280, 320 }, { 320, 360 }, { 360, 400 }, { 400, 480 },
+ { 480, 560 }, { 560, 640 }, { 640, 720 }, { 720, 800 }, { 800, 880 },
+ { 880, 1040 }, { 1040, 1200 }, { 1200, 1350 }, { 1350, 1500 },
+ { 1500, 1750 }, { 1750, 2000 }, { 2000, 2250 }, { 2250, 2500 }
+};
+
+static int cdns_dphy_rx_power_on(struct phy *phy)
+{
+ struct cdns_dphy_rx *dphy = phy_get_drvdata(phy);
+
+ /* Start RX state machine. */
+ writel(DPHY_CMN_SSM_EN | DPHY_CMN_RX_MODE_EN |
+ FIELD_PREP(DPHY_CMN_RX_BANDGAP_TIMER_MASK,
+ DPHY_CMN_RX_BANDGAP_TIMER),
+ dphy->regs + DPHY_CMN_SSM);
+
+ return 0;
+}
+
+static int cdns_dphy_rx_power_off(struct phy *phy)
+{
+ struct cdns_dphy_rx *dphy = phy_get_drvdata(phy);
+
+ writel(0, dphy->regs + DPHY_CMN_SSM);
+
+ return 0;
+}
+
+static int cdns_dphy_rx_get_band_ctrl(unsigned long hs_clk_rate)
+{
+ unsigned int rate, i;
+
+ rate = hs_clk_rate / 1000000UL;
+ /* Since CSI-2 clock is DDR, the bit rate is twice the clock rate. */
+ rate *= 2;
+
+ if (rate < bands[0].min_rate)
+ return -EOPNOTSUPP;
+
+ for (i = 0; i < ARRAY_SIZE(bands); i++)
+ if (rate < bands[i].max_rate)
+ return i;
+
+ return -EOPNOTSUPP;
+}
+
+static inline int cdns_dphy_rx_wait_for_bit(void __iomem *addr,
+ unsigned int bit)
+{
+ u32 val;
+
+ return readl_relaxed_poll_timeout(addr, val, val & BIT(bit), 10,
+ DPHY_ISO_LANE_READY_TIMEOUT_MS * 1000);
+}
+
+static int cdns_dphy_rx_wait_lane_ready(struct cdns_dphy_rx *dphy,
+ unsigned int lanes)
+{
+ static const u32 data_lane_ctrl[] = {DPHY_ISO_DL_CTRL_L0,
+ DPHY_ISO_DL_CTRL_L1,
+ DPHY_ISO_DL_CTRL_L2,
+ DPHY_ISO_DL_CTRL_L3};
+ void __iomem *reg = dphy->regs;
+ unsigned int i;
+ int ret;
+
+ /* Clock lane */
+ ret = cdns_dphy_rx_wait_for_bit(reg + DPHY_ISO_CL_CTRL_L,
+ DPHY_ISO_LANE_READY_BIT);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < lanes; i++) {
+ ret = cdns_dphy_rx_wait_for_bit(reg + data_lane_ctrl[i],
+ DPHY_ISO_LANE_READY_BIT);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+static int cdns_dphy_rx_configure(struct phy *phy,
+ union phy_configure_opts *opts)
+{
+ struct cdns_dphy_rx *dphy = phy_get_drvdata(phy);
+ unsigned int reg, lanes = opts->mipi_dphy.lanes;
+ int band_ctrl, ret;
+
+ /* Data lanes. Minimum one lane is mandatory. */
+ if (lanes < DPHY_LANES_MIN || lanes > DPHY_LANES_MAX)
+ return -EINVAL;
+
+ band_ctrl = cdns_dphy_rx_get_band_ctrl(opts->mipi_dphy.hs_clk_rate);
+ if (band_ctrl < 0)
+ return band_ctrl;
+
+ reg = FIELD_PREP(DPHY_BAND_CFG_LEFT_BAND, band_ctrl) |
+ FIELD_PREP(DPHY_BAND_CFG_RIGHT_BAND, band_ctrl);
+ writel(reg, dphy->regs + DPHY_BAND_CFG);
+
+ /*
+ * Set the required power island phase 2 time. This is mandated by DPHY
+ * specs.
+ */
+ reg = DPHY_POWER_ISLAND_EN_DATA_VAL;
+ writel(reg, dphy->regs + DPHY_POWER_ISLAND_EN_DATA);
+ reg = DPHY_POWER_ISLAND_EN_CLK_VAL;
+ writel(reg, dphy->regs + DPHY_POWER_ISLAND_EN_CLK);
+
+ ret = cdns_dphy_rx_wait_lane_ready(dphy, lanes);
+ if (ret) {
+ dev_err(dphy->dev, "DPHY wait for lane ready timeout\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static int cdns_dphy_rx_validate(struct phy *phy, enum phy_mode mode,
+ int submode, union phy_configure_opts *opts)
+{
+ int ret;
+
+ if (mode != PHY_MODE_MIPI_DPHY)
+ return -EINVAL;
+
+ ret = cdns_dphy_rx_get_band_ctrl(opts->mipi_dphy.hs_clk_rate);
+ if (ret < 0)
+ return ret;
+
+ return phy_mipi_dphy_config_validate(&opts->mipi_dphy);
+}
+
+static const struct phy_ops cdns_dphy_rx_ops = {
+ .power_on = cdns_dphy_rx_power_on,
+ .power_off = cdns_dphy_rx_power_off,
+ .configure = cdns_dphy_rx_configure,
+ .validate = cdns_dphy_rx_validate,
+};
+
+static int cdns_dphy_rx_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct phy_provider *provider;
+ struct cdns_dphy_rx *dphy;
+
+ dphy = devm_kzalloc(dev, sizeof(*dphy), GFP_KERNEL);
+ if (!dphy)
+ return -ENOMEM;
+
+ dev_set_drvdata(dev, dphy);
+ dphy->dev = dev;
+
+ dphy->regs = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(dphy->regs))
+ return PTR_ERR(dphy->regs);
+
+ dphy->phy = devm_phy_create(dev, NULL, &cdns_dphy_rx_ops);
+ if (IS_ERR(dphy->phy)) {
+ dev_err(dev, "Failed to create PHY: %ld\n", PTR_ERR(dphy->phy));
+ return PTR_ERR(dphy->phy);
+ }
+
+ phy_set_drvdata(dphy->phy, dphy);
+ provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
+ if (IS_ERR(provider)) {
+ dev_err(dev, "Failed to register PHY provider: %ld\n",
+ PTR_ERR(provider));
+ return PTR_ERR(provider);
+ }
+
+ return 0;
+}
+
+static const struct of_device_id cdns_dphy_rx_of_match[] = {
+ { .compatible = "cdns,dphy-rx" },
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, cdns_dphy_rx_of_match);
+
+static struct platform_driver cdns_dphy_rx_platform_driver = {
+ .probe = cdns_dphy_rx_probe,
+ .driver = {
+ .name = "cdns-mipi-dphy-rx",
+ .of_match_table = cdns_dphy_rx_of_match,
+ },
+};
+module_platform_driver(cdns_dphy_rx_platform_driver);
+
+MODULE_AUTHOR("Pratyush Yadav <p.yadav@ti.com>");
+MODULE_DESCRIPTION("Cadence D-PHY Rx Driver");
+MODULE_LICENSE("GPL");
projects / linux-2.6-microblaze.git / commitdiff