reset: starfive: jh7110: Add reset driver for StarFive JH7110 SoC

Add a DM reset driver for StarFive JH7110 SoC.

Note that the register base address of reset controller is the
same with the clock controller. Therefore, there is no device
tree node alone for reset driver.It binds device node in
the clock driver

Signed-off-by: Yanhong Wang <yanhong.wang@starfivetech.com>
Tested-by: Conor Dooley <conor.dooley@microchip.com>

drivers/reset/Kconfig

@@ -172,6 +172,22 @@ config RESET_SIFIVE
 	  different hw blocks like DDR, gemgxl. With this driver we leverage
 	  U-Boot's reset framework to reset these hardware blocks.
 
+config RESET_JH7110
+	bool "Reset driver for StarFive JH7110 SoC"
+	depends on DM_RESET && STARFIVE_JH7110
+	default y
+	help
+	  Support for reset controller on StarFive
+	  JH7110 SoCs.
+
+config SPL_RESET_JH7110
+	bool "SPL Reset driver for StarFive JH7110 SoC"
+	depends on SPL && STARFIVE_JH7110
+	default y
+	help
+	  Support for reset controller on StarFive
+	  JH7110 SoCs in SPL.
+
 config RESET_SYSCON
 	bool "Enable generic syscon reset driver support"
 	depends on DM_RESET

drivers/reset/Makefile

@@ -32,3 +32,4 @@ obj-$(CONFIG_RESET_SCMI) += reset-scmi.o
 obj-$(CONFIG_RESET_ZYNQMP) += reset-zynqmp.o
 obj-$(CONFIG_RESET_DRA7) += reset-dra7.o
 obj-$(CONFIG_RESET_AT91) += reset-at91.o
+obj-$(CONFIG_$(SPL_TPL_)RESET_JH7110) += reset-jh7110.o

drivers/reset/reset-jh7110.c

@@ -0,0 +1,158 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2022 StarFive Technology Co., Ltd.
+ * Author:	Yanhong Wang <yanhong.wang@starfivetech.com>
+ *
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <dm/ofnode.h>
+#include <dt-bindings/reset/starfive,jh7110-crg.h>
+#include <errno.h>
+#include <linux/iopoll.h>
+#include <reset-uclass.h>
+
+struct jh7110_reset_priv {
+	void __iomem *reg;
+	u32	assert;
+	u32	status;
+	u32	resets;
+};
+
+struct reset_info {
+	const char *compat;
+	const u32 nr_resets;
+	const u32 assert_offset;
+	const u32 status_offset;
+};
+
+static const struct reset_info jh7110_rst_info[] = {
+	{
+		.compat = "starfive,jh7110-syscrg",
+		.nr_resets = JH7110_SYSRST_END,
+		.assert_offset = 0x2F8,
+		.status_offset = 0x308,
+	},
+	{
+		.compat = "starfive,jh7110-aoncrg",
+		.nr_resets = JH7110_AONRST_END,
+		.assert_offset = 0x38,
+		.status_offset = 0x3C,
+	},
+	{
+		.compat = "starfive,jh7110-stgcrg",
+		.nr_resets = JH7110_STGRST_END,
+		.assert_offset = 0x74,
+		.status_offset = 0x78,
+	}
+};
+
+static const struct reset_info *jh7110_reset_get_cfg(const char *compat)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(jh7110_rst_info); i++)
+		if (!strcmp(compat, jh7110_rst_info[i].compat))
+			return &jh7110_rst_info[i];
+
+	return NULL;
+}
+
+static int jh7110_reset_trigger(struct jh7110_reset_priv *priv,
+				unsigned long id, bool assert)
+{
+	ulong group;
+	u32 mask, value, done = 0;
+	ulong addr;
+
+	group = id / 32;
+	mask = BIT(id % 32);
+
+	if (!assert)
+		done ^= mask;
+
+	addr = (ulong)priv->reg + priv->assert + group * sizeof(u32);
+	value = readl((ulong *)addr);
+
+	if (assert)
+		value |= mask;
+	else
+		value &= ~mask;
+
+	writel(value, (ulong *)addr);
+	addr = (ulong)priv->reg + priv->status + group * sizeof(u32);
+
+	return readl_poll_timeout((ulong *)addr, value,
+						(value & mask) == done, 1000);
+}
+
+static int jh7110_reset_assert(struct reset_ctl *rst)
+{
+	struct jh7110_reset_priv *priv = dev_get_priv(rst->dev);
+
+	jh7110_reset_trigger(priv, rst->id, true);
+
+	return 0;
+}
+
+static int jh7110_reset_deassert(struct reset_ctl *rst)
+{
+	struct jh7110_reset_priv *priv = dev_get_priv(rst->dev);
+
+	jh7110_reset_trigger(priv, rst->id, false);
+
+	return 0;
+}
+
+static int jh7110_reset_free(struct reset_ctl *rst)
+{
+	return 0;
+}
+
+static int jh7110_reset_request(struct reset_ctl *rst)
+{
+	struct jh7110_reset_priv *priv = dev_get_priv(rst->dev);
+
+	if (rst->id >= priv->resets)
+		return -EINVAL;
+
+	return 0;
+}
+
+static int jh7110_reset_probe(struct udevice *dev)
+{
+	struct jh7110_reset_priv *priv = dev_get_priv(dev);
+	const struct reset_info *cfg;
+	const char *compat;
+
+	compat = ofnode_get_property(dev_ofnode(dev), "compatible", NULL);
+	if (!compat)
+		return -EINVAL;
+
+	cfg = jh7110_reset_get_cfg(compat);
+	if (!cfg)
+		return -EINVAL;
+
+	priv->assert = cfg->assert_offset;
+	priv->status = cfg->status_offset;
+	priv->resets = cfg->nr_resets;
+	priv->reg = (void __iomem *)dev_read_addr_index(dev, 0);
+
+	return 0;
+}
+
+const struct reset_ops jh7110_reset_reset_ops = {
+	.rfree = jh7110_reset_free,
+	.request = jh7110_reset_request,
+	.rst_assert = jh7110_reset_assert,
+	.rst_deassert = jh7110_reset_deassert,
+};
+
+U_BOOT_DRIVER(jh7110_reset) = {
+	.name = "jh7110_reset",
+	.id = UCLASS_RESET,
+	.ops = &jh7110_reset_reset_ops,
+	.probe = jh7110_reset_probe,
+	.priv_auto = sizeof(struct jh7110_reset_priv),
+};