misc: Add MPC83xx serdes driver

Add a driver to configure the SerDes (Serializer/Deserializer) lanes on
the MPC83xx architecture.

Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Mario Six <mario.six@gdsys.cc>
diff --git a/drivers/misc/mpc83xx_serdes.c b/drivers/misc/mpc83xx_serdes.c
new file mode 100644
index 0000000..d572dda
--- /dev/null
+++ b/drivers/misc/mpc83xx_serdes.c
@@ -0,0 +1,185 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * (C) Copyright 2018
+ * Mario Six, Guntermann & Drunck GmbH, mario.six@gdsys.cc
+ *
+ * base on the MPC83xx serdes initialization, which is
+ *
+ * Copyright 2007,2011 Freescale Semiconductor, Inc.
+ * Copyright (C) 2008 MontaVista Software, Inc.
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <mapmem.h>
+#include <misc.h>
+
+#include "mpc83xx_serdes.h"
+
+/**
+ * struct mpc83xx_serdes_priv - Private structure for MPC83xx serdes
+ * @regs:  The device's register map
+ * @rfcks: Variable to keep the serdes reference clock selection set during
+ *	   initialization in (is or'd to every value written to SRDSCR4)
+ */
+struct mpc83xx_serdes_priv {
+	struct mpc83xx_serdes_regs *regs;
+	u32 rfcks;
+};
+
+/**
+ * setup_sata() - Configure the SerDes device to SATA mode
+ * @dev: The device to configure
+ */
+static void setup_sata(struct udevice *dev)
+{
+	struct mpc83xx_serdes_priv *priv = dev_get_priv(dev);
+
+	/* Set and clear reset bits */
+	setbits_be32(&priv->regs->srdsrstctl, SRDSRSTCTL_SATA_RESET);
+	udelay(1000);
+	clrbits_be32(&priv->regs->srdsrstctl, SRDSRSTCTL_SATA_RESET);
+
+	/* Configure SRDSCR0 */
+	clrsetbits_be32(&priv->regs->srdscr0,
+			SRDSCR0_TXEQA_MASK | SRDSCR0_TXEQE_MASK,
+			SRDSCR0_TXEQA_SATA | SRDSCR0_TXEQE_SATA);
+
+	/* Configure SRDSCR1 */
+	clrbits_be32(&priv->regs->srdscr1, SRDSCR1_PLLBW);
+
+	/* Configure SRDSCR2 */
+	clrsetbits_be32(&priv->regs->srdscr2,
+			SRDSCR2_SEIC_MASK,
+			SRDSCR2_SEIC_SATA);
+
+	/* Configure SRDSCR3 */
+	out_be32(&priv->regs->srdscr3,
+		 SRDSCR3_KFR_SATA | SRDSCR3_KPH_SATA |
+		 SRDSCR3_SDFM_SATA_PEX | SRDSCR3_SDTXL_SATA);
+
+	/* Configure SRDSCR4 */
+	out_be32(&priv->regs->srdscr4, priv->rfcks | SRDSCR4_PROT_SATA);
+}
+
+/**
+ * setup_pex() - Configure the SerDes device to PCI Express mode
+ * @dev:  The device to configure
+ * @type: The PCI Express type to configure for (x1 or x2)
+ */
+static void setup_pex(struct udevice *dev, enum pex_type type)
+{
+	struct mpc83xx_serdes_priv *priv = dev_get_priv(dev);
+
+	/* Configure SRDSCR1 */
+	setbits_be32(&priv->regs->srdscr1, SRDSCR1_PLLBW);
+
+	/* Configure SRDSCR2 */
+	clrsetbits_be32(&priv->regs->srdscr2,
+			SRDSCR2_SEIC_MASK,
+			SRDSCR2_SEIC_PEX);
+
+	/* Configure SRDSCR3 */
+	out_be32(&priv->regs->srdscr3, SRDSCR3_SDFM_SATA_PEX);
+
+	/* Configure SRDSCR4 */
+	if (type == PEX_X2)
+		out_be32(&priv->regs->srdscr4,
+			 priv->rfcks | SRDSCR4_PROT_PEX | SRDSCR4_PLANE_X2);
+	else
+		out_be32(&priv->regs->srdscr4,
+			 priv->rfcks | SRDSCR4_PROT_PEX);
+}
+
+/**
+ * setup_sgmii() - Configure the SerDes device to SGMII mode
+ * @dev: The device to configure
+ */
+static void setup_sgmii(struct udevice *dev)
+{
+	struct mpc83xx_serdes_priv *priv = dev_get_priv(dev);
+
+	/* Configure SRDSCR1 */
+	clrbits_be32(&priv->regs->srdscr1, SRDSCR1_PLLBW);
+
+	/* Configure SRDSCR2 */
+	clrsetbits_be32(&priv->regs->srdscr2,
+			SRDSCR2_SEIC_MASK,
+			SRDSCR2_SEIC_SGMII);
+
+	/* Configure SRDSCR3 */
+	out_be32(&priv->regs->srdscr3, 0);
+
+	/* Configure SRDSCR4 */
+	out_be32(&priv->regs->srdscr4, priv->rfcks | SRDSCR4_PROT_SGMII);
+}
+
+static int mpc83xx_serdes_probe(struct udevice *dev)
+{
+	struct mpc83xx_serdes_priv *priv = dev_get_priv(dev);
+	bool vdd;
+	const char *proto;
+
+	priv->regs = map_sysmem(dev_read_addr(dev),
+				sizeof(struct mpc83xx_serdes_regs));
+
+	switch (dev_read_u32_default(dev, "serdes-clk", -1)) {
+	case 100:
+		priv->rfcks = SRDSCR4_RFCKS_100;
+		break;
+	case 125:
+		priv->rfcks = SRDSCR4_RFCKS_125;
+		break;
+	case 150:
+		priv->rfcks = SRDSCR4_RFCKS_150;
+		break;
+	default:
+		debug("%s: Could not read serdes clock value\n", dev->name);
+		return -EINVAL;
+	}
+
+	vdd = dev_read_bool(dev, "vdd");
+
+	/* 1.0V corevdd */
+	if (vdd) {
+		/* DPPE/DPPA = 0 */
+		clrbits_be32(&priv->regs->srdscr0, SRDSCR0_DPP_1V2);
+
+		/* VDD = 0 */
+		clrbits_be32(&priv->regs->srdscr0, SRDSCR2_VDD_1V2);
+	}
+
+	proto = dev_read_string(dev, "proto");
+
+	/* protocol specific configuration */
+	if (!strcmp(proto, "sata")) {
+		setup_sata(dev);
+	} else if (!strcmp(proto, "pex")) {
+		setup_pex(dev, PEX_X1);
+	} else if (!strcmp(proto, "pex-x2")) {
+		setup_pex(dev, PEX_X2);
+	} else if (!strcmp(proto, "sgmii")) {
+		setup_sgmii(dev);
+	} else {
+		debug("%s: Invalid protocol value %s\n", dev->name, proto);
+		return -EINVAL;
+	}
+
+	/* Do a software reset */
+	setbits_be32(&priv->regs->srdsrstctl, SRDSRSTCTL_RST);
+
+	return 0;
+}
+
+static const struct udevice_id mpc83xx_serdes_ids[] = {
+	{ .compatible = "fsl,mpc83xx-serdes" },
+	{ }
+};
+
+U_BOOT_DRIVER(mpc83xx_serdes) = {
+	.name           = "mpc83xx_serdes",
+	.id             = UCLASS_MISC,
+	.of_match       = mpc83xx_serdes_ids,
+	.probe          = mpc83xx_serdes_probe,
+	.priv_auto_alloc_size = sizeof(struct mpc83xx_serdes_priv),
+};