drivers: net: add Aspeed MDIO driver

Add a driver for the MDIO interface for Aspeed AST2600 SOC.  The driver
only supports clause 22 for now.

Signed-off-by: Dylan Hung <dylan_hung@aspeedtech.com>
Reviewed-by: Ramon Fried <rfried.dev@gmail.com>
Reviewed-by: Ryan Chen <ryan_chen@aspeedtech.com>

diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 8e9109c..e054bec 100644 (file)
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -851,6 +851,13 @@ config FSL_LS_MDIO
          This driver supports the MDIO bus found on the Fman 10G Ethernet MACs and
          on the mEMAC (which supports both Clauses 22 and 45).
 
+config ASPEED_MDIO
+       bool "Aspeed MDIO interface support"
+       depends on DM_MDIO
+       help
+         This driver supports the MDIO bus of Aspeed AST2600 SOC.  The driver
+         currently supports Clause 22.
+
 config MDIO_MUX_MMIOREG
        bool "MDIO MUX accessed as a MMIO register access"
        depends on DM_MDIO_MUX

diff --git a/drivers/net/Makefile b/drivers/net/Makefile
index 38d0f3f..cf6294c 100644 (file)
--- a/drivers/net/Makefile
+++ b/drivers/net/Makefile
@@ -102,3 +102,4 @@ obj-$(CONFIG_HIGMACV300_ETH) += higmacv300.o
 obj-$(CONFIG_MDIO_SANDBOX) += mdio_sandbox.o
 obj-$(CONFIG_FSL_ENETC) += fsl_enetc.o fsl_enetc_mdio.o
 obj-$(CONFIG_FSL_LS_MDIO) += fsl_ls_mdio.o
+obj-$(CONFIG_ASPEED_MDIO) += aspeed_mdio.o

diff --git a/drivers/net/aspeed_mdio.c b/drivers/net/aspeed_mdio.c
new file mode 100644 (file)
index 0000000..a99715a
--- /dev/null
+++ b/drivers/net/aspeed_mdio.c
@@ -0,0 +1,128 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Aspeed MDIO driver
+ *
+ * (C) Copyright 2021 Aspeed Technology Inc.
+ *
+ * This file is inspired from the Linux kernel driver drivers/net/phy/mdio-aspeed.c
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <log.h>
+#include <miiphy.h>
+#include <net.h>
+#include <reset.h>
+#include <linux/bitops.h>
+#include <linux/bitfield.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+
+#define ASPEED_MDIO_CTRL               0x0
+#define   ASPEED_MDIO_CTRL_FIRE                BIT(31)
+#define   ASPEED_MDIO_CTRL_ST          BIT(28)
+#define     ASPEED_MDIO_CTRL_ST_C45    0
+#define     ASPEED_MDIO_CTRL_ST_C22    1
+#define   ASPEED_MDIO_CTRL_OP          GENMASK(27, 26)
+#define     MDIO_C22_OP_WRITE          0b01
+#define     MDIO_C22_OP_READ           0b10
+#define   ASPEED_MDIO_CTRL_PHYAD       GENMASK(25, 21)
+#define   ASPEED_MDIO_CTRL_REGAD       GENMASK(20, 16)
+#define   ASPEED_MDIO_CTRL_MIIWDATA    GENMASK(15, 0)
+
+#define ASPEED_MDIO_DATA               0x4
+#define   ASPEED_MDIO_DATA_MDC_THRES   GENMASK(31, 24)
+#define   ASPEED_MDIO_DATA_MDIO_EDGE   BIT(23)
+#define   ASPEED_MDIO_DATA_MDIO_LATCH  GENMASK(22, 20)
+#define   ASPEED_MDIO_DATA_IDLE                BIT(16)
+#define   ASPEED_MDIO_DATA_MIIRDATA    GENMASK(15, 0)
+
+#define ASPEED_MDIO_TIMEOUT_US         1000
+
+struct aspeed_mdio_priv {
+       void *base;
+};
+
+static int aspeed_mdio_read(struct udevice *mdio_dev, int addr, int devad, int reg)
+{
+       struct aspeed_mdio_priv *priv = dev_get_priv(mdio_dev);
+       u32 ctrl;
+       u32 data;
+       int rc;
+
+       if (devad != MDIO_DEVAD_NONE)
+               return -EOPNOTSUPP;
+
+       ctrl = ASPEED_MDIO_CTRL_FIRE
+               | FIELD_PREP(ASPEED_MDIO_CTRL_ST, ASPEED_MDIO_CTRL_ST_C22)
+               | FIELD_PREP(ASPEED_MDIO_CTRL_OP, MDIO_C22_OP_READ)
+               | FIELD_PREP(ASPEED_MDIO_CTRL_PHYAD, addr)
+               | FIELD_PREP(ASPEED_MDIO_CTRL_REGAD, reg);
+
+       writel(ctrl, priv->base + ASPEED_MDIO_CTRL);
+
+       rc = readl_poll_timeout(priv->base + ASPEED_MDIO_DATA, data,
+                               data & ASPEED_MDIO_DATA_IDLE,
+                               ASPEED_MDIO_TIMEOUT_US);
+
+       if (rc < 0)
+               return rc;
+
+       return FIELD_GET(ASPEED_MDIO_DATA_MIIRDATA, data);
+}
+
+static int aspeed_mdio_write(struct udevice *mdio_dev, int addr, int devad, int reg, u16 val)
+{
+       struct aspeed_mdio_priv *priv = dev_get_priv(mdio_dev);
+       u32 ctrl;
+
+       if (devad != MDIO_DEVAD_NONE)
+               return -EOPNOTSUPP;
+
+       ctrl = ASPEED_MDIO_CTRL_FIRE
+               | FIELD_PREP(ASPEED_MDIO_CTRL_ST, ASPEED_MDIO_CTRL_ST_C22)
+               | FIELD_PREP(ASPEED_MDIO_CTRL_OP, MDIO_C22_OP_WRITE)
+               | FIELD_PREP(ASPEED_MDIO_CTRL_PHYAD, addr)
+               | FIELD_PREP(ASPEED_MDIO_CTRL_REGAD, reg)
+               | FIELD_PREP(ASPEED_MDIO_CTRL_MIIWDATA, val);
+
+       writel(ctrl, priv->base + ASPEED_MDIO_CTRL);
+
+       return readl_poll_timeout(priv->base + ASPEED_MDIO_CTRL, ctrl,
+                                 !(ctrl & ASPEED_MDIO_CTRL_FIRE),
+                                 ASPEED_MDIO_TIMEOUT_US);
+}
+
+static const struct mdio_ops aspeed_mdio_ops = {
+       .read = aspeed_mdio_read,
+       .write = aspeed_mdio_write,
+};
+
+static int aspeed_mdio_probe(struct udevice *dev)
+{
+       struct aspeed_mdio_priv *priv = dev_get_priv(dev);
+       struct reset_ctl reset_ctl;
+       int ret = 0;
+
+       priv->base = dev_read_addr_ptr(dev);
+
+       ret = reset_get_by_index(dev, 0, &reset_ctl);
+       reset_deassert(&reset_ctl);
+
+       return 0;
+}
+
+static const struct udevice_id aspeed_mdio_ids[] = {
+       { .compatible = "aspeed,ast2600-mdio" },
+       { }
+};
+
+U_BOOT_DRIVER(aspeed_mdio) = {
+       .name = "aspeed_mdio",
+       .id = UCLASS_MDIO,
+       .of_match = aspeed_mdio_ids,
+       .probe = aspeed_mdio_probe,
+       .ops = &aspeed_mdio_ops,
+       .plat_auto = sizeof(struct mdio_perdev_priv),
+       .priv_auto = sizeof(struct aspeed_mdio_priv),
+};