reset: starfive: Factor out common JH71X0 reset code

The StarFive JH7100 SoC has additional reset controllers for audio and
video, but the registers follow the same structure. On the JH7110 the
reset registers don't get their own memory range, but instead follow the
clock control registers. The registers still follow the same structure
though, so let's factor out the common code to handle all these cases.

Tested-by: Tommaso Merciai <[email protected]>
Reviewed-by: Conor Dooley <[email protected]>
Reviewed-by: Emil Renner Berthing <[email protected]>
Signed-off-by: Emil Renner Berthing <[email protected]>
Signed-off-by: Hal Feng <[email protected]>
Signed-off-by: Conor Dooley <[email protected]>

drivers/reset/starfive/Kconfig

@@ -1,8 +1,12 @@
 # SPDX-License-Identifier: GPL-2.0-only
 
+config RESET_STARFIVE_JH71X0
+	bool
+
 config RESET_STARFIVE_JH7100
 	bool "StarFive JH7100 Reset Driver"
 	depends on ARCH_STARFIVE || COMPILE_TEST
+	select RESET_STARFIVE_JH71X0
 	default ARCH_STARFIVE
 	help
 	  This enables the reset controller driver for the StarFive JH7100 SoC.

drivers/reset/starfive/Makefile

@@ -1,2 +1,4 @@
 # SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_RESET_STARFIVE_JH71X0)		+= reset-starfive-jh71x0.o
+
 obj-$(CONFIG_RESET_STARFIVE_JH7100)		+= reset-starfive-jh7100.o

drivers/reset/starfive/reset-starfive-jh7100.c

@@ -5,158 +5,10 @@
  * Copyright (C) 2021 Emil Renner Berthing <[email protected]>
  */
 
-#include <linux/bitmap.h>
-#include <linux/io.h>
-#include <linux/io-64-nonatomic-lo-hi.h>
-#include <linux/iopoll.h>
 #include <linux/mod_devicetable.h>
 #include <linux/platform_device.h>
-#include <linux/reset-controller.h>
-#include <linux/spinlock.h>
 
-#include <dt-bindings/reset/starfive-jh7100.h>
-
-/* register offsets */
-#define JH7100_RESET_ASSERT0	0x00
-#define JH7100_RESET_ASSERT1	0x04
-#define JH7100_RESET_ASSERT2	0x08
-#define JH7100_RESET_ASSERT3	0x0c
-#define JH7100_RESET_STATUS0	0x10
-#define JH7100_RESET_STATUS1	0x14
-#define JH7100_RESET_STATUS2	0x18
-#define JH7100_RESET_STATUS3	0x1c
-
-/*
- * Writing a 1 to the n'th bit of the m'th ASSERT register asserts
- * line 32m + n, and writing a 0 deasserts the same line.
- * Most reset lines have their status inverted so a 0 bit in the STATUS
- * register means the line is asserted and a 1 means it's deasserted. A few
- * lines don't though, so store the expected value of the status registers when
- * all lines are asserted.
- */
-static const u64 jh7100_reset_asserted[2] = {
-	/* STATUS0 */
-	BIT_ULL_MASK(JH7100_RST_U74) |
-	BIT_ULL_MASK(JH7100_RST_VP6_DRESET) |
-	BIT_ULL_MASK(JH7100_RST_VP6_BRESET) |
-	/* STATUS1 */
-	BIT_ULL_MASK(JH7100_RST_HIFI4_DRESET) |
-	BIT_ULL_MASK(JH7100_RST_HIFI4_BRESET),
-	/* STATUS2 */
-	BIT_ULL_MASK(JH7100_RST_E24) |
-	/* STATUS3 */
-	0,
-};
-
-struct jh7100_reset {
-	struct reset_controller_dev rcdev;
-	/* protect registers against concurrent read-modify-write */
-	spinlock_t lock;
-	void __iomem *base;
-};
-
-static inline struct jh7100_reset *
-jh7100_reset_from(struct reset_controller_dev *rcdev)
-{
-	return container_of(rcdev, struct jh7100_reset, rcdev);
-}
-
-static int jh7100_reset_update(struct reset_controller_dev *rcdev,
-			       unsigned long id, bool assert)
-{
-	struct jh7100_reset *data = jh7100_reset_from(rcdev);
-	unsigned long offset = BIT_ULL_WORD(id);
-	u64 mask = BIT_ULL_MASK(id);
-	void __iomem *reg_assert = data->base + JH7100_RESET_ASSERT0 + offset * sizeof(u64);
-	void __iomem *reg_status = data->base + JH7100_RESET_STATUS0 + offset * sizeof(u64);
-	u64 done = jh7100_reset_asserted[offset] & mask;
-	u64 value;
-	unsigned long flags;
-	int ret;
-
-	if (!assert)
-		done ^= mask;
-
-	spin_lock_irqsave(&data->lock, flags);
-
-	value = readq(reg_assert);
-	if (assert)
-		value |= mask;
-	else
-		value &= ~mask;
-	writeq(value, reg_assert);
-
-	/* if the associated clock is gated, deasserting might otherwise hang forever */
-	ret = readq_poll_timeout_atomic(reg_status, value, (value & mask) == done, 0, 1000);
-
-	spin_unlock_irqrestore(&data->lock, flags);
-	return ret;
-}
-
-static int jh7100_reset_assert(struct reset_controller_dev *rcdev,
-			       unsigned long id)
-{
-	return jh7100_reset_update(rcdev, id, true);
-}
-
-static int jh7100_reset_deassert(struct reset_controller_dev *rcdev,
-				 unsigned long id)
-{
-	return jh7100_reset_update(rcdev, id, false);
-}
-
-static int jh7100_reset_reset(struct reset_controller_dev *rcdev,
-			      unsigned long id)
-{
-	int ret;
-
-	ret = jh7100_reset_assert(rcdev, id);
-	if (ret)
-		return ret;
-
-	return jh7100_reset_deassert(rcdev, id);
-}
-
-static int jh7100_reset_status(struct reset_controller_dev *rcdev,
-			       unsigned long id)
-{
-	struct jh7100_reset *data = jh7100_reset_from(rcdev);
-	unsigned long offset = BIT_ULL_WORD(id);
-	u64 mask = BIT_ULL_MASK(id);
-	void __iomem *reg_status = data->base + JH7100_RESET_STATUS0 + offset * sizeof(u64);
-	u64 value = readq(reg_status);
-
-	return !((value ^ jh7100_reset_asserted[offset]) & mask);
-}
-
-static const struct reset_control_ops jh7100_reset_ops = {
-	.assert		= jh7100_reset_assert,
-	.deassert	= jh7100_reset_deassert,
-	.reset		= jh7100_reset_reset,
-	.status		= jh7100_reset_status,
-};
-
-static int __init jh7100_reset_probe(struct platform_device *pdev)
-{
-	struct jh7100_reset *data;
-
-	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
-	if (!data)
-		return -ENOMEM;
-
-	data->base = devm_platform_ioremap_resource(pdev, 0);
-	if (IS_ERR(data->base))
-		return PTR_ERR(data->base);
-
-	data->rcdev.ops = &jh7100_reset_ops;
-	data->rcdev.owner = THIS_MODULE;
-	data->rcdev.nr_resets = JH7100_RSTN_END;
-	data->rcdev.dev = &pdev->dev;
-	data->rcdev.of_node = pdev->dev.of_node;
-	spin_lock_init(&data->lock);
-
-	return devm_reset_controller_register(&pdev->dev, &data->rcdev);
-}
+#include "reset-starfive-jh71x0.h"
 
 static const struct of_device_id jh7100_reset_dt_ids[] = {
 	{ .compatible = "starfive,jh7100-reset" },

drivers/reset/starfive/reset-starfive-jh71x0.c

@@ -0,0 +1,162 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Reset driver for the StarFive JH7100 SoC
+ *
+ * Copyright (C) 2021 Emil Renner Berthing <[email protected]>
+ */
+
+#include <linux/bitmap.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/io-64-nonatomic-lo-hi.h>
+#include <linux/iopoll.h>
+#include <linux/platform_device.h>
+#include <linux/reset-controller.h>
+#include <linux/spinlock.h>
+
+#include "reset-starfive-jh71x0.h"
+
+#include <dt-bindings/reset/starfive-jh7100.h>
+
+/* register offsets */
+#define JH7100_RESET_ASSERT0	0x00
+#define JH7100_RESET_ASSERT1	0x04
+#define JH7100_RESET_ASSERT2	0x08
+#define JH7100_RESET_ASSERT3	0x0c
+#define JH7100_RESET_STATUS0	0x10
+#define JH7100_RESET_STATUS1	0x14
+#define JH7100_RESET_STATUS2	0x18
+#define JH7100_RESET_STATUS3	0x1c
+
+/*
+ * Writing a 1 to the n'th bit of the m'th ASSERT register asserts
+ * line 32m + n, and writing a 0 deasserts the same line.
+ * Most reset lines have their status inverted so a 0 bit in the STATUS
+ * register means the line is asserted and a 1 means it's deasserted. A few
+ * lines don't though, so store the expected value of the status registers when
+ * all lines are asserted.
+ */
+static const u64 jh7100_reset_asserted[2] = {
+	/* STATUS0 */
+	BIT_ULL_MASK(JH7100_RST_U74) |
+	BIT_ULL_MASK(JH7100_RST_VP6_DRESET) |
+	BIT_ULL_MASK(JH7100_RST_VP6_BRESET) |
+	/* STATUS1 */
+	BIT_ULL_MASK(JH7100_RST_HIFI4_DRESET) |
+	BIT_ULL_MASK(JH7100_RST_HIFI4_BRESET),
+	/* STATUS2 */
+	BIT_ULL_MASK(JH7100_RST_E24) |
+	/* STATUS3 */
+	0,
+};
+
+struct jh7100_reset {
+	struct reset_controller_dev rcdev;
+	/* protect registers against concurrent read-modify-write */
+	spinlock_t lock;
+	void __iomem *base;
+};
+
+static inline struct jh7100_reset *
+jh7100_reset_from(struct reset_controller_dev *rcdev)
+{
+	return container_of(rcdev, struct jh7100_reset, rcdev);
+}
+
+static int jh7100_reset_update(struct reset_controller_dev *rcdev,
+			       unsigned long id, bool assert)
+{
+	struct jh7100_reset *data = jh7100_reset_from(rcdev);
+	unsigned long offset = BIT_ULL_WORD(id);
+	u64 mask = BIT_ULL_MASK(id);
+	void __iomem *reg_assert = data->base + JH7100_RESET_ASSERT0 + offset * sizeof(u64);
+	void __iomem *reg_status = data->base + JH7100_RESET_STATUS0 + offset * sizeof(u64);
+	u64 done = jh7100_reset_asserted[offset] & mask;
+	u64 value;
+	unsigned long flags;
+	int ret;
+
+	if (!assert)
+		done ^= mask;
+
+	spin_lock_irqsave(&data->lock, flags);
+
+	value = readq(reg_assert);
+	if (assert)
+		value |= mask;
+	else
+		value &= ~mask;
+	writeq(value, reg_assert);
+
+	/* if the associated clock is gated, deasserting might otherwise hang forever */
+	ret = readq_poll_timeout_atomic(reg_status, value, (value & mask) == done, 0, 1000);
+
+	spin_unlock_irqrestore(&data->lock, flags);
+	return ret;
+}
+
+static int jh7100_reset_assert(struct reset_controller_dev *rcdev,
+			       unsigned long id)
+{
+	return jh7100_reset_update(rcdev, id, true);
+}
+
+static int jh7100_reset_deassert(struct reset_controller_dev *rcdev,
+				 unsigned long id)
+{
+	return jh7100_reset_update(rcdev, id, false);
+}
+
+static int jh7100_reset_reset(struct reset_controller_dev *rcdev,
+			      unsigned long id)
+{
+	int ret;
+
+	ret = jh7100_reset_assert(rcdev, id);
+	if (ret)
+		return ret;
+
+	return jh7100_reset_deassert(rcdev, id);
+}
+
+static int jh7100_reset_status(struct reset_controller_dev *rcdev,
+			       unsigned long id)
+{
+	struct jh7100_reset *data = jh7100_reset_from(rcdev);
+	unsigned long offset = BIT_ULL_WORD(id);
+	u64 mask = BIT_ULL_MASK(id);
+	void __iomem *reg_status = data->base + JH7100_RESET_STATUS0 + offset * sizeof(u64);
+	u64 value = readq(reg_status);
+
+	return !((value ^ jh7100_reset_asserted[offset]) & mask);
+}
+
+static const struct reset_control_ops jh7100_reset_ops = {
+	.assert		= jh7100_reset_assert,
+	.deassert	= jh7100_reset_deassert,
+	.reset		= jh7100_reset_reset,
+	.status		= jh7100_reset_status,
+};
+
+int jh7100_reset_probe(struct platform_device *pdev)
+{
+	struct jh7100_reset *data;
+
+	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(data->base))
+		return PTR_ERR(data->base);
+
+	data->rcdev.ops = &jh7100_reset_ops;
+	data->rcdev.owner = THIS_MODULE;
+	data->rcdev.nr_resets = JH7100_RSTN_END;
+	data->rcdev.dev = &pdev->dev;
+	data->rcdev.of_node = pdev->dev.of_node;
+	spin_lock_init(&data->lock);
+
+	return devm_reset_controller_register(&pdev->dev, &data->rcdev);
+}
+EXPORT_SYMBOL_GPL(jh7100_reset_probe);

drivers/reset/starfive/reset-starfive-jh71x0.h

@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2021 Emil Renner Berthing <[email protected]>
+ */
+
+#ifndef __RESET_STARFIVE_JH71X0_H
+#define __RESET_STARFIVE_JH71X0_H
+
+int jh7100_reset_probe(struct platform_device *pdev);
+
+#endif /* __RESET_STARFIVE_JH71X0_H */