net: add Amlogic Meson G12A MDIO MUX driver

The Amlogic G12A & compatible SoCs embeds a mux to either communicate with
the external PHY or the internal 10/100 PHY.

This adds support for this mux as a MDIO MUX device.

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Ramon Fried <rfried.dev@gmail.com>

diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 41fa2fe..e1d3b26 100644 (file)
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -797,4 +797,11 @@ config MDIO_MUX_MMIOREG
          This driver is used for MDIO muxes driven by writing to a register in
          the MMIO physical memory.
 
+config MDIO_MUX_MESON_G12A
+       bool "MDIO MUX for Amlogic Meson G12A SoCs"
+       depends on DM_MDIO_MUX
+       help
+         This driver is used for the MDIO mux found on the Amlogic G12A & compatible
+         SoCs.
+
 endif # NETDEVICES

diff --git a/drivers/net/Makefile b/drivers/net/Makefile
index 511c87c..070ae76 100644 (file)
--- a/drivers/net/Makefile
+++ b/drivers/net/Makefile
@@ -43,6 +43,7 @@ obj-$(CONFIG_MACB) += macb.o
 obj-$(CONFIG_MCFFEC) += mcffec.o mcfmii.o
 obj-$(CONFIG_MDIO_IPQ4019) += mdio-ipq4019.o
 obj-$(CONFIG_MDIO_MUX_I2CREG) += mdio_mux_i2creg.o
+obj-$(CONFIG_MDIO_MUX_MESON_G12A) += mdio_mux_meson_g12a.o
 obj-$(CONFIG_MDIO_MUX_MMIOREG) += mdio_mux_mmioreg.o
 obj-$(CONFIG_MDIO_MUX_SANDBOX) += mdio_mux_sandbox.o
 obj-$(CONFIG_MPC8XX_FEC) += mpc8xx_fec.o

diff --git a/drivers/net/mdio_mux_meson_g12a.c b/drivers/net/mdio_mux_meson_g12a.c
new file mode 100644 (file)
index 0000000..b520bf9
--- /dev/null
+++ b/drivers/net/mdio_mux_meson_g12a.c
@@ -0,0 +1,149 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * (C) Copyright 2021 BayLibre, SAS
+ * Author: Neil Armstrong <narmstrong@baylibre.com>
+ */
+
+#include <dm.h>
+#include <errno.h>
+#include <log.h>
+#include <miiphy.h>
+#include <asm/io.h>
+#include <linux/bitfield.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         0x33010180
+#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 mdio_mux_meson_g12a_priv {
+       struct udevice *chip;
+       phys_addr_t phys;
+};
+
+static int meson_g12a_ephy_pll_init(struct mdio_mux_meson_g12a_priv *priv)
+{
+       /* Fire up the PHY PLL */
+       writel(0x29c0040a, priv->phys + ETH_PLL_CTL0);
+       writel(0x927e0000, priv->phys + ETH_PLL_CTL1);
+       writel(0xac5f49e5, priv->phys + ETH_PLL_CTL2);
+       writel(0x00000000, priv->phys + ETH_PLL_CTL3);
+       writel(0x00000000, priv->phys + ETH_PLL_CTL4);
+       writel(0x20200000, priv->phys + ETH_PLL_CTL5);
+       writel(0x0000c002, priv->phys + ETH_PLL_CTL6);
+       writel(0x00000023, priv->phys + ETH_PLL_CTL7);
+       writel(0x39c0040a, priv->phys + ETH_PLL_CTL0);
+       writel(0x19c0040a, priv->phys + ETH_PLL_CTL0);
+
+       return 0;
+}
+
+static int meson_g12a_enable_internal_mdio(struct mdio_mux_meson_g12a_priv *priv)
+{
+       /* Initialize ephy control */
+       writel(EPHY_G12A_ID, priv->phys + 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->phys + ETH_PHY_CNTL1);
+       writel(PHY_CNTL2_USE_INTERNAL |
+              PHY_CNTL2_SMI_SRC_MAC |
+              PHY_CNTL2_RX_CLK_EPHY,
+              priv->phys + ETH_PHY_CNTL2);
+
+       return 0;
+}
+
+static int meson_g12a_enable_external_mdio(struct mdio_mux_meson_g12a_priv *priv)
+{
+       /* Reset the mdio bus mux */
+       writel(0x0, priv->phys + ETH_PHY_CNTL2);
+
+       return 0;
+}
+
+static int mdio_mux_meson_g12a_select(struct udevice *mux, int cur, int sel)
+{
+       struct mdio_mux_meson_g12a_priv *priv = dev_get_priv(mux);
+
+       debug("%s: %x -> %x\n", __func__, (u32)cur, (u32)sel);
+
+       /* if last selection didn't change we're good to go */
+       if (cur == sel)
+               return 0;
+
+       switch (sel) {
+       case MESON_G12A_MDIO_EXTERNAL_ID:
+               return meson_g12a_enable_external_mdio(priv);
+       case MESON_G12A_MDIO_INTERNAL_ID:
+               return meson_g12a_enable_internal_mdio(priv);
+       default:
+               return -EINVAL;
+       }
+
+       return 0;
+}
+
+static const struct mdio_mux_ops mdio_mux_meson_g12a_ops = {
+       .select = mdio_mux_meson_g12a_select,
+};
+
+static int mdio_mux_meson_g12a_probe(struct udevice *dev)
+{
+       struct mdio_mux_meson_g12a_priv *priv = dev_get_priv(dev);
+
+       priv->phys = dev_read_addr(dev);
+
+       meson_g12a_ephy_pll_init(priv);
+
+       return 0;
+}
+
+static const struct udevice_id mdio_mux_meson_g12a_ids[] = {
+       { .compatible = "amlogic,g12a-mdio-mux" },
+       { }
+};
+
+U_BOOT_DRIVER(mdio_mux_meson_g12a) = {
+       .name           = "mdio_mux_meson_g12a",
+       .id             = UCLASS_MDIO_MUX,
+       .of_match       = mdio_mux_meson_g12a_ids,
+       .probe          = mdio_mux_meson_g12a_probe,
+       .ops            = &mdio_mux_meson_g12a_ops,
+       .priv_auto      = sizeof(struct mdio_mux_meson_g12a_priv),
+};