--- /dev/null
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright: 2017-2018 Cadence Design Systems, Inc.
+ */
+
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+
+#include <linux/phy/phy.h>
+#include <linux/phy/phy-mipi-dphy.h>
+
+#define REG_WAKEUP_TIME_NS 800
+#define DPHY_PLL_RATE_HZ 108000000
+
+/* DPHY registers */
+#define DPHY_PMA_CMN(reg) (reg)
+#define DPHY_PMA_LCLK(reg) (0x100 + (reg))
+#define DPHY_PMA_LDATA(lane, reg) (0x200 + ((lane) * 0x100) + (reg))
+#define DPHY_PMA_RCLK(reg) (0x600 + (reg))
+#define DPHY_PMA_RDATA(lane, reg) (0x700 + ((lane) * 0x100) + (reg))
+#define DPHY_PCS(reg) (0xb00 + (reg))
+
+#define DPHY_CMN_SSM DPHY_PMA_CMN(0x20)
+#define DPHY_CMN_SSM_EN BIT(0)
+#define DPHY_CMN_TX_MODE_EN BIT(9)
+
+#define DPHY_CMN_PWM DPHY_PMA_CMN(0x40)
+#define DPHY_CMN_PWM_DIV(x) ((x) << 20)
+#define DPHY_CMN_PWM_LOW(x) ((x) << 10)
+#define DPHY_CMN_PWM_HIGH(x) (x)
+
+#define DPHY_CMN_FBDIV DPHY_PMA_CMN(0x4c)
+#define DPHY_CMN_FBDIV_VAL(low, high) (((high) << 11) | ((low) << 22))
+#define DPHY_CMN_FBDIV_FROM_REG (BIT(10) | BIT(21))
+
+#define DPHY_CMN_OPIPDIV DPHY_PMA_CMN(0x50)
+#define DPHY_CMN_IPDIV_FROM_REG BIT(0)
+#define DPHY_CMN_IPDIV(x) ((x) << 1)
+#define DPHY_CMN_OPDIV_FROM_REG BIT(6)
+#define DPHY_CMN_OPDIV(x) ((x) << 7)
+
+#define DPHY_PSM_CFG DPHY_PCS(0x4)
+#define DPHY_PSM_CFG_FROM_REG BIT(0)
+#define DPHY_PSM_CLK_DIV(x) ((x) << 1)
+
+#define DSI_HBP_FRAME_OVERHEAD 12
+#define DSI_HSA_FRAME_OVERHEAD 14
+#define DSI_HFP_FRAME_OVERHEAD 6
+#define DSI_HSS_VSS_VSE_FRAME_OVERHEAD 4
+#define DSI_BLANKING_FRAME_OVERHEAD 6
+#define DSI_NULL_FRAME_OVERHEAD 6
+#define DSI_EOT_PKT_SIZE 4
+
+struct cdns_dphy_cfg {
+ u8 pll_ipdiv;
+ u8 pll_opdiv;
+ u16 pll_fbdiv;
+ unsigned int nlanes;
+};
+
+enum cdns_dphy_clk_lane_cfg {
+ DPHY_CLK_CFG_LEFT_DRIVES_ALL = 0,
+ DPHY_CLK_CFG_LEFT_DRIVES_RIGHT = 1,
+ DPHY_CLK_CFG_LEFT_DRIVES_LEFT = 2,
+ DPHY_CLK_CFG_RIGHT_DRIVES_ALL = 3,
+};
+
+struct cdns_dphy;
+struct cdns_dphy_ops {
+ int (*probe)(struct cdns_dphy *dphy);
+ void (*remove)(struct cdns_dphy *dphy);
+ void (*set_psm_div)(struct cdns_dphy *dphy, u8 div);
+ void (*set_clk_lane_cfg)(struct cdns_dphy *dphy,
+ enum cdns_dphy_clk_lane_cfg cfg);
+ void (*set_pll_cfg)(struct cdns_dphy *dphy,
+ const struct cdns_dphy_cfg *cfg);
+ unsigned long (*get_wakeup_time_ns)(struct cdns_dphy *dphy);
+};
+
+struct cdns_dphy {
+ struct cdns_dphy_cfg cfg;
+ void __iomem *regs;
+ struct clk *psm_clk;
+ struct clk *pll_ref_clk;
+ const struct cdns_dphy_ops *ops;
+ struct phy *phy;
+};
+
+static int cdns_dsi_get_dphy_pll_cfg(struct cdns_dphy *dphy,
+ struct cdns_dphy_cfg *cfg,
+ struct phy_configure_opts_mipi_dphy *opts,
+ unsigned int *dsi_hfp_ext)
+{
+ unsigned long pll_ref_hz = clk_get_rate(dphy->pll_ref_clk);
+ u64 dlane_bps;
+
+ memset(cfg, 0, sizeof(*cfg));
+
+ if (pll_ref_hz < 9600000 || pll_ref_hz >= 150000000)
+ return -EINVAL;
+ else if (pll_ref_hz < 19200000)
+ cfg->pll_ipdiv = 1;
+ else if (pll_ref_hz < 38400000)
+ cfg->pll_ipdiv = 2;
+ else if (pll_ref_hz < 76800000)
+ cfg->pll_ipdiv = 4;
+ else
+ cfg->pll_ipdiv = 8;
+
+ dlane_bps = opts->hs_clk_rate;
+
+ if (dlane_bps > 2500000000UL || dlane_bps < 160000000UL)
+ return -EINVAL;
+ else if (dlane_bps >= 1250000000)
+ cfg->pll_opdiv = 1;
+ else if (dlane_bps >= 630000000)
+ cfg->pll_opdiv = 2;
+ else if (dlane_bps >= 320000000)
+ cfg->pll_opdiv = 4;
+ else if (dlane_bps >= 160000000)
+ cfg->pll_opdiv = 8;
+
+ cfg->pll_fbdiv = DIV_ROUND_UP_ULL(dlane_bps * 2 * cfg->pll_opdiv *
+ cfg->pll_ipdiv,
+ pll_ref_hz);
+
+ return 0;
+}
+
+static int cdns_dphy_setup_psm(struct cdns_dphy *dphy)
+{
+ unsigned long psm_clk_hz = clk_get_rate(dphy->psm_clk);
+ unsigned long psm_div;
+
+ if (!psm_clk_hz || psm_clk_hz > 100000000)
+ return -EINVAL;
+
+ psm_div = DIV_ROUND_CLOSEST(psm_clk_hz, 1000000);
+ if (dphy->ops->set_psm_div)
+ dphy->ops->set_psm_div(dphy, psm_div);
+
+ return 0;
+}
+
+static void cdns_dphy_set_clk_lane_cfg(struct cdns_dphy *dphy,
+ enum cdns_dphy_clk_lane_cfg cfg)
+{
+ if (dphy->ops->set_clk_lane_cfg)
+ dphy->ops->set_clk_lane_cfg(dphy, cfg);
+}
+
+static void cdns_dphy_set_pll_cfg(struct cdns_dphy *dphy,
+ const struct cdns_dphy_cfg *cfg)
+{
+ if (dphy->ops->set_pll_cfg)
+ dphy->ops->set_pll_cfg(dphy, cfg);
+}
+
+static unsigned long cdns_dphy_get_wakeup_time_ns(struct cdns_dphy *dphy)
+{
+ return dphy->ops->get_wakeup_time_ns(dphy);
+}
+
+static unsigned long cdns_dphy_ref_get_wakeup_time_ns(struct cdns_dphy *dphy)
+{
+ /* Default wakeup time is 800 ns (in a simulated environment). */
+ return 800;
+}
+
+static void cdns_dphy_ref_set_pll_cfg(struct cdns_dphy *dphy,
+ const struct cdns_dphy_cfg *cfg)
+{
+ u32 fbdiv_low, fbdiv_high;
+
+ fbdiv_low = (cfg->pll_fbdiv / 4) - 2;
+ fbdiv_high = cfg->pll_fbdiv - fbdiv_low - 2;
+
+ writel(DPHY_CMN_IPDIV_FROM_REG | DPHY_CMN_OPDIV_FROM_REG |
+ DPHY_CMN_IPDIV(cfg->pll_ipdiv) |
+ DPHY_CMN_OPDIV(cfg->pll_opdiv),
+ dphy->regs + DPHY_CMN_OPIPDIV);
+ writel(DPHY_CMN_FBDIV_FROM_REG |
+ DPHY_CMN_FBDIV_VAL(fbdiv_low, fbdiv_high),
+ dphy->regs + DPHY_CMN_FBDIV);
+ writel(DPHY_CMN_PWM_HIGH(6) | DPHY_CMN_PWM_LOW(0x101) |
+ DPHY_CMN_PWM_DIV(0x8),
+ dphy->regs + DPHY_CMN_PWM);
+}
+
+static void cdns_dphy_ref_set_psm_div(struct cdns_dphy *dphy, u8 div)
+{
+ writel(DPHY_PSM_CFG_FROM_REG | DPHY_PSM_CLK_DIV(div),
+ dphy->regs + DPHY_PSM_CFG);
+}
+
+/*
+ * This is the reference implementation of DPHY hooks. Specific integration of
+ * this IP may have to re-implement some of them depending on how they decided
+ * to wire things in the SoC.
+ */
+static const struct cdns_dphy_ops ref_dphy_ops = {
+ .get_wakeup_time_ns = cdns_dphy_ref_get_wakeup_time_ns,
+ .set_pll_cfg = cdns_dphy_ref_set_pll_cfg,
+ .set_psm_div = cdns_dphy_ref_set_psm_div,
+};
+
+static int cdns_dphy_config_from_opts(struct phy *phy,
+ struct phy_configure_opts_mipi_dphy *opts,
+ struct cdns_dphy_cfg *cfg)
+{
+ struct cdns_dphy *dphy = phy_get_drvdata(phy);
+ unsigned int dsi_hfp_ext = 0;
+ int ret;
+
+ ret = phy_mipi_dphy_config_validate(opts);
+ if (ret)
+ return ret;
+
+ ret = cdns_dsi_get_dphy_pll_cfg(dphy, cfg,
+ opts, &dsi_hfp_ext);
+ if (ret)
+ return ret;
+
+ opts->wakeup = cdns_dphy_get_wakeup_time_ns(dphy) / 1000;
+
+ return 0;
+}
+
+static int cdns_dphy_validate(struct phy *phy, enum phy_mode mode, int submode,
+ union phy_configure_opts *opts)
+{
+ struct cdns_dphy_cfg cfg = { 0 };
+
+ if (mode != PHY_MODE_MIPI_DPHY)
+ return -EINVAL;
+
+ return cdns_dphy_config_from_opts(phy, &opts->mipi_dphy, &cfg);
+}
+
+static int cdns_dphy_configure(struct phy *phy, union phy_configure_opts *opts)
+{
+ struct cdns_dphy *dphy = phy_get_drvdata(phy);
+ struct cdns_dphy_cfg cfg = { 0 };
+ int ret;
+
+ ret = cdns_dphy_config_from_opts(phy, &opts->mipi_dphy, &cfg);
+ if (ret)
+ return ret;
+
+ /*
+ * Configure the internal PSM clk divider so that the DPHY has a
+ * 1MHz clk (or something close).
+ */
+ ret = cdns_dphy_setup_psm(dphy);
+ if (ret)
+ return ret;
+
+ /*
+ * Configure attach clk lanes to data lanes: the DPHY has 2 clk lanes
+ * and 8 data lanes, each clk lane can be attache different set of
+ * data lanes. The 2 groups are named 'left' and 'right', so here we
+ * just say that we want the 'left' clk lane to drive the 'left' data
+ * lanes.
+ */
+ cdns_dphy_set_clk_lane_cfg(dphy, DPHY_CLK_CFG_LEFT_DRIVES_LEFT);
+
+ /*
+ * Configure the DPHY PLL that will be used to generate the TX byte
+ * clk.
+ */
+ cdns_dphy_set_pll_cfg(dphy, &cfg);
+
+ return 0;
+}
+
+static int cdns_dphy_power_on(struct phy *phy)
+{
+ struct cdns_dphy *dphy = phy_get_drvdata(phy);
+
+ clk_prepare_enable(dphy->psm_clk);
+ clk_prepare_enable(dphy->pll_ref_clk);
+
+ /* Start TX state machine. */
+ writel(DPHY_CMN_SSM_EN | DPHY_CMN_TX_MODE_EN,
+ dphy->regs + DPHY_CMN_SSM);
+
+ return 0;
+}
+
+static int cdns_dphy_power_off(struct phy *phy)
+{
+ struct cdns_dphy *dphy = phy_get_drvdata(phy);
+
+ clk_disable_unprepare(dphy->pll_ref_clk);
+ clk_disable_unprepare(dphy->psm_clk);
+
+ return 0;
+}
+
+static const struct phy_ops cdns_dphy_ops = {
+ .configure = cdns_dphy_configure,
+ .validate = cdns_dphy_validate,
+ .power_on = cdns_dphy_power_on,
+ .power_off = cdns_dphy_power_off,
+};
+
+static int cdns_dphy_probe(struct platform_device *pdev)
+{
+ struct phy_provider *phy_provider;
+ struct cdns_dphy *dphy;
+ struct resource *res;
+ int ret;
+
+ dphy = devm_kzalloc(&pdev->dev, sizeof(*dphy), GFP_KERNEL);
+ if (!dphy)
+ return -ENOMEM;
+ dev_set_drvdata(&pdev->dev, dphy);
+
+ dphy->ops = of_device_get_match_data(&pdev->dev);
+ if (!dphy->ops)
+ return -EINVAL;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ dphy->regs = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(dphy->regs))
+ return PTR_ERR(dphy->regs);
+
+ dphy->psm_clk = devm_clk_get(&pdev->dev, "psm");
+ if (IS_ERR(dphy->psm_clk))
+ return PTR_ERR(dphy->psm_clk);
+
+ dphy->pll_ref_clk = devm_clk_get(&pdev->dev, "pll_ref");
+ if (IS_ERR(dphy->pll_ref_clk))
+ return PTR_ERR(dphy->pll_ref_clk);
+
+ if (dphy->ops->probe) {
+ ret = dphy->ops->probe(dphy);
+ if (ret)
+ return ret;
+ }
+
+ dphy->phy = devm_phy_create(&pdev->dev, NULL, &cdns_dphy_ops);
+ if (IS_ERR(dphy->phy)) {
+ dev_err(&pdev->dev, "failed to create PHY\n");
+ if (dphy->ops->remove)
+ dphy->ops->remove(dphy);
+ return PTR_ERR(dphy->phy);
+ }
+
+ phy_set_drvdata(dphy->phy, dphy);
+ phy_provider = devm_of_phy_provider_register(&pdev->dev,
+ of_phy_simple_xlate);
+
+ return PTR_ERR_OR_ZERO(phy_provider);
+}
+
+static int cdns_dphy_remove(struct platform_device *pdev)
+{
+ struct cdns_dphy *dphy = dev_get_drvdata(&pdev->dev);
+
+ if (dphy->ops->remove)
+ dphy->ops->remove(dphy);
+
+ return 0;
+}
+
+static const struct of_device_id cdns_dphy_of_match[] = {
+ { .compatible = "cdns,dphy", .data = &ref_dphy_ops },
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, cdns_dphy_of_match);
+
+static struct platform_driver cdns_dphy_platform_driver = {
+ .probe = cdns_dphy_probe,
+ .remove = cdns_dphy_remove,
+ .driver = {
+ .name = "cdns-mipi-dphy",
+ .of_match_table = cdns_dphy_of_match,
+ },
+};
+module_platform_driver(cdns_dphy_platform_driver);
+
+MODULE_AUTHOR("Maxime Ripard <maxime.ripard@bootlin.com>");
+MODULE_DESCRIPTION("Cadence MIPI D-PHY Driver");
+MODULE_LICENSE("GPL");
projects / users / hch / xfs.git / commitdiff