From 1c866de57bfcd2250fba09f5c186a4c3c256e31a Mon Sep 17 00:00:00 2001
From: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Date: Mon, 20 Feb 2023 14:50:30 +0900
Subject: [PATCH] reset: uniphier: Add USB glue reset support

Add reset control support in USB glue logic. This needs to control
the external clocks and resets for the logic before accessing the
glue logic.

The USB dm tree when using dwc3-generic is the following:

   USB glue
     +-- controller       (need controller-reset)
     +-- controller-reset (need syscon-reset)
     +-- phy

The controller needs to deassert "controller-reset" in USB glue before
the controller registers are accessed. The glue needs to deassert
"syscon-reset" before the glue registers are accessed.

The glue itself doesn't have "syscon-reset", so the controller-reset
controls "syscon-reset" instead.

Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Reviewed-by: Marek Vasut <marex@denx.de>
---
 drivers/reset/reset-uniphier.c | 78 +++++++++++++++++++++++++++++++++-
 1 file changed, 77 insertions(+), 1 deletion(-)

diff --git a/drivers/reset/reset-uniphier.c b/drivers/reset/reset-uniphier.c
index 7adae51873..35e3ccebd7 100644
--- a/drivers/reset/reset-uniphier.c
+++ b/drivers/reset/reset-uniphier.c
@@ -2,6 +2,7 @@
 /*
  * Copyright (C) 2016 Socionext Inc.
  *   Author: Masahiro Yamada <yamada.masahiro@socionext.com>
+ *   Author: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
  */
 
 #include <common.h>
@@ -9,6 +10,8 @@
 #include <log.h>
 #include <malloc.h>
 #include <reset-uclass.h>
+#include <clk.h>
+#include <reset.h>
 #include <dm/device_compat.h>
 #include <linux/bitops.h>
 #include <linux/io.h>
@@ -178,10 +181,17 @@ static const struct uniphier_reset_data uniphier_pro4_peri_reset_data[] = {
 	UNIPHIER_RESET_END,
 };
 
+/* Glue reset data */
+static const struct uniphier_reset_data uniphier_pro4_usb3_reset_data[] = {
+	UNIPHIER_RESETX(15, 0, 15)
+};
+
 /* core implementaton */
 struct uniphier_reset_priv {
 	void __iomem *base;
 	const struct uniphier_reset_data *data;
+	struct clk_bulk		clks;
+	struct reset_ctl_bulk	rsts;
 };
 
 static int uniphier_reset_update(struct reset_ctl *reset_ctl, int assert)
@@ -233,10 +243,47 @@ static const struct reset_ops uniphier_reset_ops = {
 	.rst_deassert = uniphier_reset_deassert,
 };
 
+static int uniphier_reset_rst_init(struct udevice *dev)
+{
+	struct uniphier_reset_priv *priv = dev_get_priv(dev);
+	int ret;
+
+	ret = reset_get_bulk(dev, &priv->rsts);
+	if (ret == -ENOSYS || ret == -ENOENT)
+		return 0;
+	else if (ret)
+		return ret;
+
+	ret = reset_deassert_bulk(&priv->rsts);
+	if (ret)
+		reset_release_bulk(&priv->rsts);
+
+	return ret;
+}
+
+static int uniphier_reset_clk_init(struct udevice *dev)
+{
+	struct uniphier_reset_priv *priv = dev_get_priv(dev);
+	int ret;
+
+	ret = clk_get_bulk(dev, &priv->clks);
+	if (ret == -ENOSYS || ret == -ENOENT)
+		return 0;
+	if (ret)
+		return ret;
+
+	ret = clk_enable_bulk(&priv->clks);
+	if (ret)
+		clk_release_bulk(&priv->clks);
+
+	return ret;
+}
+
 static int uniphier_reset_probe(struct udevice *dev)
 {
 	struct uniphier_reset_priv *priv = dev_get_priv(dev);
 	fdt_addr_t addr;
+	int ret;
 
 	addr = dev_read_addr(dev->parent);
 	if (addr == FDT_ADDR_T_NONE)
@@ -248,7 +295,11 @@ static int uniphier_reset_probe(struct udevice *dev)
 
 	priv->data = (void *)dev_get_driver_data(dev);
 
-	return 0;
+	ret = uniphier_reset_clk_init(dev);
+	if (ret)
+		return ret;
+
+	return uniphier_reset_rst_init(dev);
 }
 
 static const struct udevice_id uniphier_reset_match[] = {
@@ -355,6 +406,31 @@ static const struct udevice_id uniphier_reset_match[] = {
 		.compatible = "socionext,uniphier-pxs3-peri-reset",
 		.data = (ulong)uniphier_pro4_peri_reset_data,
 	},
+	/* USB glue reset */
+	{
+		.compatible = "socionext,uniphier-pro4-usb3-reset",
+		.data = (ulong)uniphier_pro4_usb3_reset_data,
+	},
+	{
+		.compatible = "socionext,uniphier-pro5-usb3-reset",
+		.data = (ulong)uniphier_pro4_usb3_reset_data,
+	},
+	{
+		.compatible = "socionext,uniphier-pxs2-usb3-reset",
+		.data = (ulong)uniphier_pro4_usb3_reset_data,
+	},
+	{
+		.compatible = "socionext,uniphier-ld20-usb3-reset",
+		.data = (ulong)uniphier_pro4_usb3_reset_data,
+	},
+	{
+		.compatible = "socionext,uniphier-pxs3-usb3-reset",
+		.data = (ulong)uniphier_pro4_usb3_reset_data,
+	},
+	{
+		.compatible = "socionext,uniphier-nx1-usb3-reset",
+		.data = (ulong)uniphier_pro4_usb3_reset_data,
+	},
 	{ /* sentinel */ }
 };
 
-- 
2.39.5