--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2019 Baylibre, SAS.
+ * Author: Jerome Brunet <jbrunet@baylibre.com>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/mdio-mux.h>
+#include <linux/module.h>
+#include <linux/phy.h>
+#include <linux/platform_device.h>
+
+#define ETH_PLL_STS 0x40
+#define ETH_PLL_CTL0 0x44
+#define PLL_CTL0_LOCK_DIG BIT(30)
+#define PLL_CTL0_RST BIT(29)
+#define PLL_CTL0_EN BIT(28)
+#define PLL_CTL0_SEL BIT(23)
+#define PLL_CTL0_N GENMASK(14, 10)
+#define PLL_CTL0_M GENMASK(8, 0)
+#define PLL_LOCK_TIMEOUT 1000000
+#define PLL_MUX_NUM_PARENT 2
+#define ETH_PLL_CTL1 0x48
+#define ETH_PLL_CTL2 0x4c
+#define ETH_PLL_CTL3 0x50
+#define ETH_PLL_CTL4 0x54
+#define ETH_PLL_CTL5 0x58
+#define ETH_PLL_CTL6 0x5c
+#define ETH_PLL_CTL7 0x60
+
+#define ETH_PHY_CNTL0 0x80
+#define EPHY_G12A_ID 0x33000180
+#define ETH_PHY_CNTL1 0x84
+#define PHY_CNTL1_ST_MODE GENMASK(2, 0)
+#define PHY_CNTL1_ST_PHYADD GENMASK(7, 3)
+#define EPHY_DFLT_ADD 8
+#define PHY_CNTL1_MII_MODE GENMASK(15, 14)
+#define EPHY_MODE_RMII 0x1
+#define PHY_CNTL1_CLK_EN BIT(16)
+#define PHY_CNTL1_CLKFREQ BIT(17)
+#define PHY_CNTL1_PHY_ENB BIT(18)
+#define ETH_PHY_CNTL2 0x88
+#define PHY_CNTL2_USE_INTERNAL BIT(5)
+#define PHY_CNTL2_SMI_SRC_MAC BIT(6)
+#define PHY_CNTL2_RX_CLK_EPHY BIT(9)
+
+#define MESON_G12A_MDIO_EXTERNAL_ID 0
+#define MESON_G12A_MDIO_INTERNAL_ID 1
+
+struct g12a_mdio_mux {
+ bool pll_is_enabled;
+ void __iomem *regs;
+ void *mux_handle;
+ struct clk *pclk;
+ struct clk *pll;
+};
+
+struct g12a_ephy_pll {
+ void __iomem *base;
+ struct clk_hw hw;
+};
+
+#define g12a_ephy_pll_to_dev(_hw) \
+ container_of(_hw, struct g12a_ephy_pll, hw)
+
+static unsigned long g12a_ephy_pll_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct g12a_ephy_pll *pll = g12a_ephy_pll_to_dev(hw);
+ u32 val, m, n;
+
+ val = readl(pll->base + ETH_PLL_CTL0);
+ m = FIELD_GET(PLL_CTL0_M, val);
+ n = FIELD_GET(PLL_CTL0_N, val);
+
+ return parent_rate * m / n;
+}
+
+static int g12a_ephy_pll_enable(struct clk_hw *hw)
+{
+ struct g12a_ephy_pll *pll = g12a_ephy_pll_to_dev(hw);
+ u32 val = readl(pll->base + ETH_PLL_CTL0);
+
+ /* Apply both enable an reset */
+ val |= PLL_CTL0_RST | PLL_CTL0_EN;
+ writel(val, pll->base + ETH_PLL_CTL0);
+
+ /* Clear the reset to let PLL lock */
+ val &= ~PLL_CTL0_RST;
+ writel(val, pll->base + ETH_PLL_CTL0);
+
+ /* Poll on the digital lock instead of the usual analog lock
+ * This is done because bit 31 is unreliable on some SoC. Bit
+ * 31 may indicate that the PLL is not lock eventhough the clock
+ * is actually running
+ */
+ return readl_poll_timeout(pll->base + ETH_PLL_CTL0, val,
+ val & PLL_CTL0_LOCK_DIG, 0, PLL_LOCK_TIMEOUT);
+}
+
+static void g12a_ephy_pll_disable(struct clk_hw *hw)
+{
+ struct g12a_ephy_pll *pll = g12a_ephy_pll_to_dev(hw);
+ u32 val;
+
+ val = readl(pll->base + ETH_PLL_CTL0);
+ val &= ~PLL_CTL0_EN;
+ val |= PLL_CTL0_RST;
+ writel(val, pll->base + ETH_PLL_CTL0);
+}
+
+static int g12a_ephy_pll_is_enabled(struct clk_hw *hw)
+{
+ struct g12a_ephy_pll *pll = g12a_ephy_pll_to_dev(hw);
+ unsigned int val;
+
+ val = readl(pll->base + ETH_PLL_CTL0);
+
+ return (val & PLL_CTL0_LOCK_DIG) ? 1 : 0;
+}
+
+static void g12a_ephy_pll_init(struct clk_hw *hw)
+{
+ struct g12a_ephy_pll *pll = g12a_ephy_pll_to_dev(hw);
+
+ /* Apply PLL HW settings */
+ writel(0x29c0040a, pll->base + ETH_PLL_CTL0);
+ writel(0x927e0000, pll->base + ETH_PLL_CTL1);
+ writel(0xac5f49e5, pll->base + ETH_PLL_CTL2);
+ writel(0x00000000, pll->base + ETH_PLL_CTL3);
+ writel(0x00000000, pll->base + ETH_PLL_CTL4);
+ writel(0x20200000, pll->base + ETH_PLL_CTL5);
+ writel(0x0000c002, pll->base + ETH_PLL_CTL6);
+ writel(0x00000023, pll->base + ETH_PLL_CTL7);
+}
+
+static const struct clk_ops g12a_ephy_pll_ops = {
+ .recalc_rate = g12a_ephy_pll_recalc_rate,
+ .is_enabled = g12a_ephy_pll_is_enabled,
+ .enable = g12a_ephy_pll_enable,
+ .disable = g12a_ephy_pll_disable,
+ .init = g12a_ephy_pll_init,
+};
+
+static int g12a_enable_internal_mdio(struct g12a_mdio_mux *priv)
+{
+ int ret;
+
+ /* Enable the phy clock */
+ if (!priv->pll_is_enabled) {
+ ret = clk_prepare_enable(priv->pll);
+ if (ret)
+ return ret;
+ }
+
+ priv->pll_is_enabled = true;
+
+ /* Initialize ephy control */
+ writel(EPHY_G12A_ID, priv->regs + ETH_PHY_CNTL0);
+ writel(FIELD_PREP(PHY_CNTL1_ST_MODE, 3) |
+ FIELD_PREP(PHY_CNTL1_ST_PHYADD, EPHY_DFLT_ADD) |
+ FIELD_PREP(PHY_CNTL1_MII_MODE, EPHY_MODE_RMII) |
+ PHY_CNTL1_CLK_EN |
+ PHY_CNTL1_CLKFREQ |
+ PHY_CNTL1_PHY_ENB,
+ priv->regs + ETH_PHY_CNTL1);
+ writel(PHY_CNTL2_USE_INTERNAL |
+ PHY_CNTL2_SMI_SRC_MAC |
+ PHY_CNTL2_RX_CLK_EPHY,
+ priv->regs + ETH_PHY_CNTL2);
+
+ return 0;
+}
+
+static int g12a_enable_external_mdio(struct g12a_mdio_mux *priv)
+{
+ /* Reset the mdio bus mux */
+ writel_relaxed(0x0, priv->regs + ETH_PHY_CNTL2);
+
+ /* Disable the phy clock if enabled */
+ if (priv->pll_is_enabled) {
+ clk_disable_unprepare(priv->pll);
+ priv->pll_is_enabled = false;
+ }
+
+ return 0;
+}
+
+static int g12a_mdio_switch_fn(int current_child, int desired_child,
+ void *data)
+{
+ struct g12a_mdio_mux *priv = dev_get_drvdata(data);
+
+ if (current_child == desired_child)
+ return 0;
+
+ switch (desired_child) {
+ case MESON_G12A_MDIO_EXTERNAL_ID:
+ return g12a_enable_external_mdio(priv);
+ case MESON_G12A_MDIO_INTERNAL_ID:
+ return g12a_enable_internal_mdio(priv);
+ default:
+ return -EINVAL;
+ }
+}
+
+static const struct of_device_id g12a_mdio_mux_match[] = {
+ { .compatible = "amlogic,g12a-mdio-mux", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, g12a_mdio_mux_match);
+
+static int g12a_ephy_glue_clk_register(struct device *dev)
+{
+ struct g12a_mdio_mux *priv = dev_get_drvdata(dev);
+ const char *parent_names[PLL_MUX_NUM_PARENT];
+ struct clk_init_data init;
+ struct g12a_ephy_pll *pll;
+ struct clk_mux *mux;
+ struct clk *clk;
+ char *name;
+ int i;
+
+ /* get the mux parents */
+ for (i = 0; i < PLL_MUX_NUM_PARENT; i++) {
+ char in_name[8];
+
+ snprintf(in_name, sizeof(in_name), "clkin%d", i);
+ clk = devm_clk_get(dev, in_name);
+ if (IS_ERR(clk)) {
+ if (PTR_ERR(clk) != -EPROBE_DEFER)
+ dev_err(dev, "Missing clock %s\n", in_name);
+ return PTR_ERR(clk);
+ }
+
+ parent_names[i] = __clk_get_name(clk);
+ }
+
+ /* create the input mux */
+ mux = devm_kzalloc(dev, sizeof(*mux), GFP_KERNEL);
+ if (!mux)
+ return -ENOMEM;
+
+ name = kasprintf(GFP_KERNEL, "%s#mux", dev_name(dev));
+ if (!name)
+ return -ENOMEM;
+
+ init.name = name;
+ init.ops = &clk_mux_ro_ops;
+ init.flags = 0;
+ init.parent_names = parent_names;
+ init.num_parents = PLL_MUX_NUM_PARENT;
+
+ mux->reg = priv->regs + ETH_PLL_CTL0;
+ mux->shift = __ffs(PLL_CTL0_SEL);
+ mux->mask = PLL_CTL0_SEL >> mux->shift;
+ mux->hw.init = &init;
+
+ clk = devm_clk_register(dev, &mux->hw);
+ kfree(name);
+ if (IS_ERR(clk)) {
+ dev_err(dev, "failed to register input mux\n");
+ return PTR_ERR(clk);
+ }
+
+ /* create the pll */
+ pll = devm_kzalloc(dev, sizeof(*pll), GFP_KERNEL);
+ if (!pll)
+ return -ENOMEM;
+
+ name = kasprintf(GFP_KERNEL, "%s#pll", dev_name(dev));
+ if (!name)
+ return -ENOMEM;
+
+ init.name = name;
+ init.ops = &g12a_ephy_pll_ops;
+ init.flags = 0;
+ parent_names[0] = __clk_get_name(clk);
+ init.parent_names = parent_names;
+ init.num_parents = 1;
+
+ pll->base = priv->regs;
+ pll->hw.init = &init;
+
+ clk = devm_clk_register(dev, &pll->hw);
+ kfree(name);
+ if (IS_ERR(clk)) {
+ dev_err(dev, "failed to register input mux\n");
+ return PTR_ERR(clk);
+ }
+
+ priv->pll = clk;
+
+ return 0;
+}
+
+static int g12a_mdio_mux_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct g12a_mdio_mux *priv;
+ struct resource *res;
+ int ret;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, priv);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ priv->regs = devm_ioremap_resource(dev, res);
+ if (IS_ERR(priv->regs))
+ return PTR_ERR(priv->regs);
+
+ priv->pclk = devm_clk_get(dev, "pclk");
+ if (IS_ERR(priv->pclk)) {
+ ret = PTR_ERR(priv->pclk);
+ if (ret != -EPROBE_DEFER)
+ dev_err(dev, "failed to get peripheral clock\n");
+ return ret;
+ }
+
+ /* Make sure the device registers are clocked */
+ ret = clk_prepare_enable(priv->pclk);
+ if (ret) {
+ dev_err(dev, "failed to enable peripheral clock");
+ return ret;
+ }
+
+ /* Register PLL in CCF */
+ ret = g12a_ephy_glue_clk_register(dev);
+ if (ret)
+ goto err;
+
+ ret = mdio_mux_init(dev, dev->of_node, g12a_mdio_switch_fn,
+ &priv->mux_handle, dev, NULL);
+ if (ret) {
+ if (ret != -EPROBE_DEFER)
+ dev_err(dev, "mdio multiplexer init failed: %d", ret);
+ goto err;
+ }
+
+ return 0;
+
+err:
+ clk_disable_unprepare(priv->pclk);
+ return ret;
+}
+
+static int g12a_mdio_mux_remove(struct platform_device *pdev)
+{
+ struct g12a_mdio_mux *priv = platform_get_drvdata(pdev);
+
+ mdio_mux_uninit(priv->mux_handle);
+
+ if (priv->pll_is_enabled)
+ clk_disable_unprepare(priv->pll);
+
+ clk_disable_unprepare(priv->pclk);
+
+ return 0;
+}
+
+static struct platform_driver g12a_mdio_mux_driver = {
+ .probe = g12a_mdio_mux_probe,
+ .remove = g12a_mdio_mux_remove,
+ .driver = {
+ .name = "g12a-mdio_mux",
+ .of_match_table = g12a_mdio_mux_match,
+ },
+};
+module_platform_driver(g12a_mdio_mux_driver);
+
+MODULE_DESCRIPTION("Amlogic G12a MDIO multiplexer driver");
+MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
+MODULE_LICENSE("GPL v2");
projects / linux.git / commitdiff