[PATCH 00/15] rework at91-reset driver

[PATCH 00/15] rework at91-reset driver

[Claudiu.Beznea]

Hi,

The following patches rework the at91-reset driver and solves
the SAM9X60 VDDCORE fast drop in the first 100us after power down.

Thank you,
Claudiu Beznea

Claudiu Beznea (15):
  power: reset: at91-reset: introduce struct at91_reset
  power: reset: at91-reset: add ramc_base[] to struct at91_reset
  power: reset: at91-reset: add sclk to struct at91_reset
  power: reset: at91-reset: add notifier block to struct at91_reset
  power: reset: at91-reset: convert reset in pointer to struct
    at91_reset
  power: reset: at91-reset: pass rstc base address to
    at91_reset_status()
  power: reset: at91-reset: devm_kzalloc() for at91_reset data structure
  power: reset: at91-reset: introduce struct at91_reset_data
  power: reset: at91-reset: introduce args member in at91_reset_data
  power: reset: at91-reset: use r4 as tmp argument
  power: reset: at91-reset: introduce ramc_lpr to struct at91_reset
  power: reset: at91-reset: make at91sam9g45_restart() generic
  power: reset: at91-reset: keep only one reset function
  power: reset: at91-reset: get rid of at91_reset_data
  power: reset: at91-reset: handle nrst async for sam9x60

 drivers/power/reset/at91-reset.c | 190 +++++++++++++++++++--------------------
 1 file changed, 94 insertions(+), 96 deletions(-)

-- 
2.7.4

[PATCH 01/15] power: reset: at91-reset: introduce struct at91_reset

[Claudiu.Beznea]

Introduce struct at91_reset intended to keep all the at91 reset controller
data.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
---
 drivers/power/reset/at91-reset.c | 26 +++++++++++++++++---------
 1 file changed, 17 insertions(+), 9 deletions(-)

diff --git a/drivers/power/reset/at91-reset.c b/drivers/power/reset/at91-reset.c
index d94e3267c3b6..2df0610e5527 100644
--- a/drivers/power/reset/at91-reset.c
+++ b/drivers/power/reset/at91-reset.c
@@ -49,7 +49,13 @@ enum reset_type {
 	RESET_TYPE_ULP2		= 8,
 };
 
-static void __iomem *at91_ramc_base[2], *at91_rstc_base;
+struct at91_reset {
+	void __iomem *rstc_base;
+};
+
+static struct at91_reset reset;
+
+static void __iomem *at91_ramc_base[2];
 static struct clk *sclk;
 
 /*
@@ -76,7 +82,7 @@ static int at91sam9260_restart(struct notifier_block *this, unsigned long mode,
 		"b	.\n\t"
 		:
 		: "r" (at91_ramc_base[0]),
-		  "r" (at91_rstc_base),
+		  "r" (reset.rstc_base),
 		  "r" (1),
 		  "r" cpu_to_le32(AT91_SDRAMC_LPCB_POWER_DOWN),
 		  "r" cpu_to_le32(AT91_RSTC_KEY | AT91_RSTC_PERRST | AT91_RSTC_PROCRST));
@@ -119,7 +125,7 @@ static int at91sam9g45_restart(struct notifier_block *this, unsigned long mode,
 		:
 		: "r" (at91_ramc_base[0]),
 		  "r" (at91_ramc_base[1]),
-		  "r" (at91_rstc_base),
+		  "r" (reset.rstc_base),
 		  "r" (1),
 		  "r" cpu_to_le32(AT91_DDRSDRC_LPCB_POWER_DOWN),
 		  "r" cpu_to_le32(AT91_RSTC_KEY | AT91_RSTC_PERRST | AT91_RSTC_PROCRST)
@@ -131,8 +137,8 @@ static int at91sam9g45_restart(struct notifier_block *this, unsigned long mode,
 static int sama5d3_restart(struct notifier_block *this, unsigned long mode,
 			   void *cmd)
 {
-	writel(AT91_RSTC_KEY | AT91_RSTC_PERRST | AT91_RSTC_PROCRST,
-	       at91_rstc_base);
+	writel(cpu_to_le32(AT91_RSTC_KEY | AT91_RSTC_PERRST | AT91_RSTC_PROCRST),
+	       reset.rstc_base);
 
 	return NOTIFY_DONE;
 }
@@ -140,14 +146,16 @@ static int sama5d3_restart(struct notifier_block *this, unsigned long mode,
 static int samx7_restart(struct notifier_block *this, unsigned long mode,
 			 void *cmd)
 {
-	writel(AT91_RSTC_KEY | AT91_RSTC_PROCRST, at91_rstc_base);
+	writel(cpu_to_le32(AT91_RSTC_KEY | AT91_RSTC_PROCRST),
+	       reset.rstc_base);
+
 	return NOTIFY_DONE;
 }
 
 static void __init at91_reset_status(struct platform_device *pdev)
 {
 	const char *reason;
-	u32 reg = readl(at91_rstc_base + AT91_RSTC_SR);
+	u32 reg = readl(reset.rstc_base + AT91_RSTC_SR);
 
 	switch ((reg & AT91_RSTC_RSTTYP) >> 8) {
 	case RESET_TYPE_GENERAL:
@@ -208,8 +216,8 @@ static int __init at91_reset_probe(struct platform_device *pdev)
 	struct device_node *np;
 	int ret, idx = 0;
 
-	at91_rstc_base = of_iomap(pdev->dev.of_node, 0);
-	if (!at91_rstc_base) {
+	reset.rstc_base = of_iomap(pdev->dev.of_node, 0);
+	if (!reset.rstc_base) {
 		dev_err(&pdev->dev, "Could not map reset controller address\n");
 		return -ENODEV;
 	}
-- 
2.7.4

[PATCH 03/15] power: reset: at91-reset: add sclk to struct at91_reset

[Claudiu.Beznea]

Add sclk to struct at91_reset.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
---
 drivers/power/reset/at91-reset.c | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/drivers/power/reset/at91-reset.c b/drivers/power/reset/at91-reset.c
index 999d3a1653d2..1bc39bfda0aa 100644
--- a/drivers/power/reset/at91-reset.c
+++ b/drivers/power/reset/at91-reset.c
@@ -52,12 +52,11 @@ enum reset_type {
 struct at91_reset {
 	void __iomem *rstc_base;
 	void __iomem *ramc_base[2];
+	struct clk *sclk;
 };
 
 static struct at91_reset reset;
 
-static struct clk *sclk;
-
 /*
 * unless the SDRAM is cleanly shutdown before we hit the
 * reset register it can be left driving the data bus and
@@ -238,11 +237,11 @@ static int __init at91_reset_probe(struct platform_device *pdev)
 	match = of_match_node(at91_reset_of_match, pdev->dev.of_node);
 	at91_restart_nb.notifier_call = match->data;
 
-	sclk = devm_clk_get(&pdev->dev, NULL);
-	if (IS_ERR(sclk))
-		return PTR_ERR(sclk);
+	reset.sclk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(reset.sclk))
+		return PTR_ERR(reset.sclk);
 
-	ret = clk_prepare_enable(sclk);
+	ret = clk_prepare_enable(reset.sclk);
 	if (ret) {
 		dev_err(&pdev->dev, "Could not enable slow clock\n");
 		return ret;
@@ -250,7 +249,7 @@ static int __init at91_reset_probe(struct platform_device *pdev)
 
 	ret = register_restart_handler(&at91_restart_nb);
 	if (ret) {
-		clk_disable_unprepare(sclk);
+		clk_disable_unprepare(reset.sclk);
 		return ret;
 	}
 
@@ -262,7 +261,7 @@ static int __init at91_reset_probe(struct platform_device *pdev)
 static int __exit at91_reset_remove(struct platform_device *pdev)
 {
 	unregister_restart_handler(&at91_restart_nb);
-	clk_disable_unprepare(sclk);
+	clk_disable_unprepare(reset.sclk);
 
 	return 0;
 }
-- 
2.7.4

[PATCH 02/15] power: reset: at91-reset: add ramc_base[] to struct at91_reset

[Claudiu.Beznea]

Add ramc_base[] to struct at91_reset.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
---
 drivers/power/reset/at91-reset.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/power/reset/at91-reset.c b/drivers/power/reset/at91-reset.c
index 2df0610e5527..999d3a1653d2 100644
--- a/drivers/power/reset/at91-reset.c
+++ b/drivers/power/reset/at91-reset.c
@@ -51,11 +51,11 @@ enum reset_type {
 
 struct at91_reset {
 	void __iomem *rstc_base;
+	void __iomem *ramc_base[2];
 };
 
 static struct at91_reset reset;
 
-static void __iomem *at91_ramc_base[2];
 static struct clk *sclk;
 
 /*
@@ -81,7 +81,7 @@ static int at91sam9260_restart(struct notifier_block *this, unsigned long mode,
 
 		"b	.\n\t"
 		:
-		: "r" (at91_ramc_base[0]),
+		: "r" (reset.ramc_base[0]),
 		  "r" (reset.rstc_base),
 		  "r" (1),
 		  "r" cpu_to_le32(AT91_SDRAMC_LPCB_POWER_DOWN),
@@ -123,8 +123,8 @@ static int at91sam9g45_restart(struct notifier_block *this, unsigned long mode,
 
 		"	b	.\n\t"
 		:
-		: "r" (at91_ramc_base[0]),
-		  "r" (at91_ramc_base[1]),
+		: "r" (reset.ramc_base[0]),
+		  "r" (reset.ramc_base[1]),
 		  "r" (reset.rstc_base),
 		  "r" (1),
 		  "r" cpu_to_le32(AT91_DDRSDRC_LPCB_POWER_DOWN),
@@ -225,8 +225,8 @@ static int __init at91_reset_probe(struct platform_device *pdev)
 	if (!of_device_is_compatible(pdev->dev.of_node, "atmel,sama5d3-rstc")) {
 		/* we need to shutdown the ddr controller, so get ramc base */
 		for_each_matching_node(np, at91_ramc_of_match) {
-			at91_ramc_base[idx] = of_iomap(np, 0);
-			if (!at91_ramc_base[idx]) {
+			reset.ramc_base[idx] = of_iomap(np, 0);
+			if (!reset.ramc_base[idx]) {
 				dev_err(&pdev->dev, "Could not map ram controller address\n");
 				of_node_put(np);
 				return -ENODEV;
-- 
2.7.4

[PATCH 04/15] power: reset: at91-reset: add notifier block to struct at91_reset

[Claudiu.Beznea]

Add struct notifier_block to struct at91_reset.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
---
 drivers/power/reset/at91-reset.c | 12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)

diff --git a/drivers/power/reset/at91-reset.c b/drivers/power/reset/at91-reset.c
index 1bc39bfda0aa..e8840193620d 100644
--- a/drivers/power/reset/at91-reset.c
+++ b/drivers/power/reset/at91-reset.c
@@ -53,6 +53,7 @@ struct at91_reset {
 	void __iomem *rstc_base;
 	void __iomem *ramc_base[2];
 	struct clk *sclk;
+	struct notifier_block nb;
 };
 
 static struct at91_reset reset;
@@ -205,10 +206,6 @@ static const struct of_device_id at91_reset_of_match[] = {
 };
 MODULE_DEVICE_TABLE(of, at91_reset_of_match);
 
-static struct notifier_block at91_restart_nb = {
-	.priority = 192,
-};
-
 static int __init at91_reset_probe(struct platform_device *pdev)
 {
 	const struct of_device_id *match;
@@ -235,7 +232,8 @@ static int __init at91_reset_probe(struct platform_device *pdev)
 	}
 
 	match = of_match_node(at91_reset_of_match, pdev->dev.of_node);
-	at91_restart_nb.notifier_call = match->data;
+	reset.nb.notifier_call = match->data;
+	reset.nb.priority = 192;
 
 	reset.sclk = devm_clk_get(&pdev->dev, NULL);
 	if (IS_ERR(reset.sclk))
@@ -247,7 +245,7 @@ static int __init at91_reset_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	ret = register_restart_handler(&at91_restart_nb);
+	ret = register_restart_handler(&reset.nb);
 	if (ret) {
 		clk_disable_unprepare(reset.sclk);
 		return ret;
@@ -260,7 +258,7 @@ static int __init at91_reset_probe(struct platform_device *pdev)
 
 static int __exit at91_reset_remove(struct platform_device *pdev)
 {
-	unregister_restart_handler(&at91_restart_nb);
+	unregister_restart_handler(&reset.nb);
 	clk_disable_unprepare(reset.sclk);
 
 	return 0;
-- 
2.7.4

[PATCH 05/15] power: reset: at91-reset: convert reset in pointer to struct at91_reset

[Claudiu.Beznea]

Convert reset in pointer to struct at91_reset.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
---
 drivers/power/reset/at91-reset.c | 50 ++++++++++++++++++++++------------------
 1 file changed, 27 insertions(+), 23 deletions(-)

diff --git a/drivers/power/reset/at91-reset.c b/drivers/power/reset/at91-reset.c
index e8840193620d..4bb5eef4b258 100644
--- a/drivers/power/reset/at91-reset.c
+++ b/drivers/power/reset/at91-reset.c
@@ -56,7 +56,7 @@ struct at91_reset {
 	struct notifier_block nb;
 };
 
-static struct at91_reset reset;
+static struct at91_reset *reset;
 
 /*
 * unless the SDRAM is cleanly shutdown before we hit the
@@ -81,8 +81,8 @@ static int at91sam9260_restart(struct notifier_block *this, unsigned long mode,
 
 		"b	.\n\t"
 		:
-		: "r" (reset.ramc_base[0]),
-		  "r" (reset.rstc_base),
+		: "r" (reset->ramc_base[0]),
+		  "r" (reset->rstc_base),
 		  "r" (1),
 		  "r" cpu_to_le32(AT91_SDRAMC_LPCB_POWER_DOWN),
 		  "r" cpu_to_le32(AT91_RSTC_KEY | AT91_RSTC_PERRST | AT91_RSTC_PROCRST));
@@ -123,9 +123,9 @@ static int at91sam9g45_restart(struct notifier_block *this, unsigned long mode,
 
 		"	b	.\n\t"
 		:
-		: "r" (reset.ramc_base[0]),
-		  "r" (reset.ramc_base[1]),
-		  "r" (reset.rstc_base),
+		: "r" (reset->ramc_base[0]),
+		  "r" (reset->ramc_base[1]),
+		  "r" (reset->rstc_base),
 		  "r" (1),
 		  "r" cpu_to_le32(AT91_DDRSDRC_LPCB_POWER_DOWN),
 		  "r" cpu_to_le32(AT91_RSTC_KEY | AT91_RSTC_PERRST | AT91_RSTC_PROCRST)
@@ -138,7 +138,7 @@ static int sama5d3_restart(struct notifier_block *this, unsigned long mode,
 			   void *cmd)
 {
 	writel(cpu_to_le32(AT91_RSTC_KEY | AT91_RSTC_PERRST | AT91_RSTC_PROCRST),
-	       reset.rstc_base);
+	       reset->rstc_base);
 
 	return NOTIFY_DONE;
 }
@@ -147,7 +147,7 @@ static int samx7_restart(struct notifier_block *this, unsigned long mode,
 			 void *cmd)
 {
 	writel(cpu_to_le32(AT91_RSTC_KEY | AT91_RSTC_PROCRST),
-	       reset.rstc_base);
+	       reset->rstc_base);
 
 	return NOTIFY_DONE;
 }
@@ -155,7 +155,7 @@ static int samx7_restart(struct notifier_block *this, unsigned long mode,
 static void __init at91_reset_status(struct platform_device *pdev)
 {
 	const char *reason;
-	u32 reg = readl(reset.rstc_base + AT91_RSTC_SR);
+	u32 reg = readl(reset->rstc_base + AT91_RSTC_SR);
 
 	switch ((reg & AT91_RSTC_RSTTYP) >> 8) {
 	case RESET_TYPE_GENERAL:
@@ -212,8 +212,12 @@ static int __init at91_reset_probe(struct platform_device *pdev)
 	struct device_node *np;
 	int ret, idx = 0;
 
-	reset.rstc_base = of_iomap(pdev->dev.of_node, 0);
-	if (!reset.rstc_base) {
+	reset = devm_kzalloc(&pdev->dev, sizeof(*reset), GFP_KERNEL);
+	if (!reset)
+		return -ENOMEM;
+
+	reset->rstc_base = of_iomap(pdev->dev.of_node, 0);
+	if (!reset->rstc_base) {
 		dev_err(&pdev->dev, "Could not map reset controller address\n");
 		return -ENODEV;
 	}
@@ -221,8 +225,8 @@ static int __init at91_reset_probe(struct platform_device *pdev)
 	if (!of_device_is_compatible(pdev->dev.of_node, "atmel,sama5d3-rstc")) {
 		/* we need to shutdown the ddr controller, so get ramc base */
 		for_each_matching_node(np, at91_ramc_of_match) {
-			reset.ramc_base[idx] = of_iomap(np, 0);
-			if (!reset.ramc_base[idx]) {
+			reset->ramc_base[idx] = of_iomap(np, 0);
+			if (!reset->ramc_base[idx]) {
 				dev_err(&pdev->dev, "Could not map ram controller address\n");
 				of_node_put(np);
 				return -ENODEV;
@@ -232,22 +236,22 @@ static int __init at91_reset_probe(struct platform_device *pdev)
 	}
 
 	match = of_match_node(at91_reset_of_match, pdev->dev.of_node);
-	reset.nb.notifier_call = match->data;
-	reset.nb.priority = 192;
+	reset->nb.notifier_call = match->data;
+	reset->nb.priority = 192;
 
-	reset.sclk = devm_clk_get(&pdev->dev, NULL);
-	if (IS_ERR(reset.sclk))
-		return PTR_ERR(reset.sclk);
+	reset->sclk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(reset->sclk))
+		return PTR_ERR(reset->sclk);
 
-	ret = clk_prepare_enable(reset.sclk);
+	ret = clk_prepare_enable(reset->sclk);
 	if (ret) {
 		dev_err(&pdev->dev, "Could not enable slow clock\n");
 		return ret;
 	}
 
-	ret = register_restart_handler(&reset.nb);
+	ret = register_restart_handler(&reset->nb);
 	if (ret) {
-		clk_disable_unprepare(reset.sclk);
+		clk_disable_unprepare(reset->sclk);
 		return ret;
 	}
 
@@ -258,8 +262,8 @@ static int __init at91_reset_probe(struct platform_device *pdev)
 
 static int __exit at91_reset_remove(struct platform_device *pdev)
 {
-	unregister_restart_handler(&reset.nb);
-	clk_disable_unprepare(reset.sclk);
+	unregister_restart_handler(&reset->nb);
+	clk_disable_unprepare(reset->sclk);
 
 	return 0;
 }
-- 
2.7.4

[PATCH 08/15] power: reset: at91-reset: introduce struct at91_reset_data

[Claudiu.Beznea]

Introduce struct at91_reset_data to be able to provide per SoC
data. At the moment this being only notifier callback.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
---
 drivers/power/reset/at91-reset.c | 50 +++++++++++++++++++++++++++++++++++-----
 1 file changed, 44 insertions(+), 6 deletions(-)

diff --git a/drivers/power/reset/at91-reset.c b/drivers/power/reset/at91-reset.c
index 7ba77555e9e1..c653bd7ac29a 100644
--- a/drivers/power/reset/at91-reset.c
+++ b/drivers/power/reset/at91-reset.c
@@ -49,6 +49,11 @@ enum reset_type {
 	RESET_TYPE_ULP2		= 8,
 };
 
+struct at91_reset_data {
+	int (*notifier_call)(struct notifier_block *this, unsigned long mode,
+			     void *cmd);
+};
+
 struct at91_reset {
 	void __iomem *rstc_base;
 	void __iomem *ramc_base[2];
@@ -203,18 +208,50 @@ static const struct of_device_id at91_ramc_of_match[] = {
 	{ /* sentinel */ }
 };
 
+static const struct at91_reset_data at91sam9260_reset_data = {
+	.notifier_call = at91sam9260_restart,
+};
+
+static const struct at91_reset_data at91sam9g45_reset_data = {
+	.notifier_call = at91sam9g45_restart,
+};
+
+static const struct at91_reset_data sama5d3_reset_data = {
+	.notifier_call = sama5d3_restart,
+};
+
+static const struct at91_reset_data samx7_reset_data = {
+	.notifier_call = samx7_restart,
+};
+
 static const struct of_device_id at91_reset_of_match[] = {
-	{ .compatible = "atmel,at91sam9260-rstc", .data = at91sam9260_restart },
-	{ .compatible = "atmel,at91sam9g45-rstc", .data = at91sam9g45_restart },
-	{ .compatible = "atmel,sama5d3-rstc", .data = sama5d3_restart },
-	{ .compatible = "atmel,samx7-rstc", .data = samx7_restart },
-	{ .compatible = "microchip,sam9x60-rstc", .data = samx7_restart },
+	{
+		.compatible = "atmel,at91sam9260-rstc",
+		.data = &at91sam9260_reset_data
+	},
+	{
+		.compatible = "atmel,at91sam9g45-rstc",
+		.data = &at91sam9g45_reset_data
+	},
+	{
+		.compatible = "atmel,sama5d3-rstc",
+		.data = &sama5d3_reset_data
+	},
+	{
+		.compatible = "atmel,samx7-rstc",
+		.data = &samx7_reset_data
+	},
+	{
+		.compatible = "microchip,sam9x60-rstc",
+		.data = &samx7_reset_data
+	},
 	{ /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, at91_reset_of_match);
 
 static int __init at91_reset_probe(struct platform_device *pdev)
 {
+	const struct at91_reset_data *reset_data;
 	const struct of_device_id *match;
 	struct at91_reset *reset;
 	struct device_node *np;
@@ -244,7 +281,8 @@ static int __init at91_reset_probe(struct platform_device *pdev)
 	}
 
 	match = of_match_node(at91_reset_of_match, pdev->dev.of_node);
-	reset->nb.notifier_call = match->data;
+	reset_data = match->data;
+	reset->nb.notifier_call = reset_data->notifier_call;
 	reset->nb.priority = 192;
 
 	reset->sclk = devm_clk_get(&pdev->dev, NULL);
-- 
2.7.4

[PATCH 06/15] power: reset: at91-reset: pass rstc base address to at91_reset_status()

[Claudiu.Beznea]

Add new argument to at91_reset_status() that is the pointer to reset
controller base address.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
---
 drivers/power/reset/at91-reset.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/power/reset/at91-reset.c b/drivers/power/reset/at91-reset.c
index 4bb5eef4b258..bd05496c5ac7 100644
--- a/drivers/power/reset/at91-reset.c
+++ b/drivers/power/reset/at91-reset.c
@@ -152,10 +152,11 @@ static int samx7_restart(struct notifier_block *this, unsigned long mode,
 	return NOTIFY_DONE;
 }
 
-static void __init at91_reset_status(struct platform_device *pdev)
+static void __init at91_reset_status(struct platform_device *pdev,
+				     void __iomem *base)
 {
 	const char *reason;
-	u32 reg = readl(reset->rstc_base + AT91_RSTC_SR);
+	u32 reg = readl(base + AT91_RSTC_SR);
 
 	switch ((reg & AT91_RSTC_RSTTYP) >> 8) {
 	case RESET_TYPE_GENERAL:
@@ -255,7 +256,7 @@ static int __init at91_reset_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	at91_reset_status(pdev);
+	at91_reset_status(pdev, reset->rstc_base);
 
 	return 0;
 }
-- 
2.7.4

[PATCH 07/15] power: reset: at91-reset: devm_kzalloc() for at91_reset data structure

[Claudiu.Beznea]

Allocate at91_reset data on probe and set it as platform data.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
---
 drivers/power/reset/at91-reset.c | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/drivers/power/reset/at91-reset.c b/drivers/power/reset/at91-reset.c
index bd05496c5ac7..7ba77555e9e1 100644
--- a/drivers/power/reset/at91-reset.c
+++ b/drivers/power/reset/at91-reset.c
@@ -56,8 +56,6 @@ struct at91_reset {
 	struct notifier_block nb;
 };
 
-static struct at91_reset *reset;
-
 /*
 * unless the SDRAM is cleanly shutdown before we hit the
 * reset register it can be left driving the data bus and
@@ -66,6 +64,8 @@ static struct at91_reset *reset;
 static int at91sam9260_restart(struct notifier_block *this, unsigned long mode,
 			       void *cmd)
 {
+	struct at91_reset *reset = container_of(this, struct at91_reset, nb);
+
 	asm volatile(
 		/* Align to cache lines */
 		".balign 32\n\t"
@@ -93,6 +93,8 @@ static int at91sam9260_restart(struct notifier_block *this, unsigned long mode,
 static int at91sam9g45_restart(struct notifier_block *this, unsigned long mode,
 			       void *cmd)
 {
+	struct at91_reset *reset = container_of(this, struct at91_reset, nb);
+
 	asm volatile(
 		/*
 		 * Test wether we have a second RAM controller to care
@@ -137,6 +139,8 @@ static int at91sam9g45_restart(struct notifier_block *this, unsigned long mode,
 static int sama5d3_restart(struct notifier_block *this, unsigned long mode,
 			   void *cmd)
 {
+	struct at91_reset *reset = container_of(this, struct at91_reset, nb);
+
 	writel(cpu_to_le32(AT91_RSTC_KEY | AT91_RSTC_PERRST | AT91_RSTC_PROCRST),
 	       reset->rstc_base);
 
@@ -146,6 +150,8 @@ static int sama5d3_restart(struct notifier_block *this, unsigned long mode,
 static int samx7_restart(struct notifier_block *this, unsigned long mode,
 			 void *cmd)
 {
+	struct at91_reset *reset = container_of(this, struct at91_reset, nb);
+
 	writel(cpu_to_le32(AT91_RSTC_KEY | AT91_RSTC_PROCRST),
 	       reset->rstc_base);
 
@@ -210,6 +216,7 @@ MODULE_DEVICE_TABLE(of, at91_reset_of_match);
 static int __init at91_reset_probe(struct platform_device *pdev)
 {
 	const struct of_device_id *match;
+	struct at91_reset *reset;
 	struct device_node *np;
 	int ret, idx = 0;
 
@@ -250,6 +257,8 @@ static int __init at91_reset_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	platform_set_drvdata(pdev, reset);
+
 	ret = register_restart_handler(&reset->nb);
 	if (ret) {
 		clk_disable_unprepare(reset->sclk);
@@ -263,6 +272,8 @@ static int __init at91_reset_probe(struct platform_device *pdev)
 
 static int __exit at91_reset_remove(struct platform_device *pdev)
 {
+	struct at91_reset *reset = platform_get_drvdata(pdev);
+
 	unregister_restart_handler(&reset->nb);
 	clk_disable_unprepare(reset->sclk);
 
-- 
2.7.4

[PATCH 10/15] power: reset: at91-reset: use r4 as tmp argument

[Claudiu.Beznea]

Use r4 as temporary register. On ARM r0-r3 should be used to hold
function arguments.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
---
 drivers/power/reset/at91-reset.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/power/reset/at91-reset.c b/drivers/power/reset/at91-reset.c
index dc48f6850796..3b1d566350f4 100644
--- a/drivers/power/reset/at91-reset.c
+++ b/drivers/power/reset/at91-reset.c
@@ -113,8 +113,8 @@ static int at91sam9g45_restart(struct notifier_block *this, unsigned long mode,
 		"beq	1f\n\t"
 
 		/* Then, test that the RAM controller is enabled */
-		"ldr	r0, [%1]\n\t"
-		"cmp	r0, #0\n\t"
+		"ldr	r4, [%1]\n\t"
+		"cmp	r4, #0\n\t"
 
 		/* Align to cache lines */
 		".balign 32\n\t"
@@ -138,7 +138,7 @@ static int at91sam9g45_restart(struct notifier_block *this, unsigned long mode,
 		  "r" (1),
 		  "r" cpu_to_le32(AT91_DDRSDRC_LPCB_POWER_DOWN),
 		  "r" (reset->args)
-		: "r0");
+		: "r4");
 
 	return NOTIFY_DONE;
 }
-- 
2.7.4

[PATCH 09/15] power: reset: at91-reset: introduce args member in at91_reset_data

[Claudiu.Beznea]

Introduce args member in struct at91_reset_data. It stores the value
that needs to be written in mode register so that the reboot actions
to happen. With these changes samx7_restart() could be removed.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
---
 drivers/power/reset/at91-reset.c | 27 +++++++++++----------------
 1 file changed, 11 insertions(+), 16 deletions(-)

diff --git a/drivers/power/reset/at91-reset.c b/drivers/power/reset/at91-reset.c
index c653bd7ac29a..dc48f6850796 100644
--- a/drivers/power/reset/at91-reset.c
+++ b/drivers/power/reset/at91-reset.c
@@ -52,6 +52,7 @@ enum reset_type {
 struct at91_reset_data {
 	int (*notifier_call)(struct notifier_block *this, unsigned long mode,
 			     void *cmd);
+	u32 args;
 };
 
 struct at91_reset {
@@ -59,6 +60,7 @@ struct at91_reset {
 	void __iomem *ramc_base[2];
 	struct clk *sclk;
 	struct notifier_block nb;
+	u32 args;
 };
 
 /*
@@ -90,7 +92,7 @@ static int at91sam9260_restart(struct notifier_block *this, unsigned long mode,
 		  "r" (reset->rstc_base),
 		  "r" (1),
 		  "r" cpu_to_le32(AT91_SDRAMC_LPCB_POWER_DOWN),
-		  "r" cpu_to_le32(AT91_RSTC_KEY | AT91_RSTC_PERRST | AT91_RSTC_PROCRST));
+		  "r" (reset->args));
 
 	return NOTIFY_DONE;
 }
@@ -135,7 +137,7 @@ static int at91sam9g45_restart(struct notifier_block *this, unsigned long mode,
 		  "r" (reset->rstc_base),
 		  "r" (1),
 		  "r" cpu_to_le32(AT91_DDRSDRC_LPCB_POWER_DOWN),
-		  "r" cpu_to_le32(AT91_RSTC_KEY | AT91_RSTC_PERRST | AT91_RSTC_PROCRST)
+		  "r" (reset->args)
 		: "r0");
 
 	return NOTIFY_DONE;
@@ -146,19 +148,7 @@ static int sama5d3_restart(struct notifier_block *this, unsigned long mode,
 {
 	struct at91_reset *reset = container_of(this, struct at91_reset, nb);
 
-	writel(cpu_to_le32(AT91_RSTC_KEY | AT91_RSTC_PERRST | AT91_RSTC_PROCRST),
-	       reset->rstc_base);
-
-	return NOTIFY_DONE;
-}
-
-static int samx7_restart(struct notifier_block *this, unsigned long mode,
-			 void *cmd)
-{
-	struct at91_reset *reset = container_of(this, struct at91_reset, nb);
-
-	writel(cpu_to_le32(AT91_RSTC_KEY | AT91_RSTC_PROCRST),
-	       reset->rstc_base);
+	writel(reset->args, reset->rstc_base);
 
 	return NOTIFY_DONE;
 }
@@ -210,18 +200,22 @@ static const struct of_device_id at91_ramc_of_match[] = {
 
 static const struct at91_reset_data at91sam9260_reset_data = {
 	.notifier_call = at91sam9260_restart,
+	.args = AT91_RSTC_KEY | AT91_RSTC_PERRST | AT91_RSTC_PROCRST,
 };
 
 static const struct at91_reset_data at91sam9g45_reset_data = {
 	.notifier_call = at91sam9g45_restart,
+	.args = AT91_RSTC_KEY | AT91_RSTC_PERRST | AT91_RSTC_PROCRST,
 };
 
 static const struct at91_reset_data sama5d3_reset_data = {
 	.notifier_call = sama5d3_restart,
+	.args = AT91_RSTC_KEY | AT91_RSTC_PERRST | AT91_RSTC_PROCRST,
 };
 
 static const struct at91_reset_data samx7_reset_data = {
-	.notifier_call = samx7_restart,
+	.notifier_call = sama5d3_restart,
+	.args = AT91_RSTC_KEY | AT91_RSTC_PROCRST,
 };
 
 static const struct of_device_id at91_reset_of_match[] = {
@@ -284,6 +278,7 @@ static int __init at91_reset_probe(struct platform_device *pdev)
 	reset_data = match->data;
 	reset->nb.notifier_call = reset_data->notifier_call;
 	reset->nb.priority = 192;
+	reset->args = reset_data->args;
 
 	reset->sclk = devm_clk_get(&pdev->dev, NULL);
 	if (IS_ERR(reset->sclk))
-- 
2.7.4

[PATCH 11/15] power: reset: at91-reset: introduce ramc_lpr to struct at91_reset

[Claudiu.Beznea]

Introduce ramc_lpr to struct at91_reset. This will lead to the
unification of at91sam9260_restart() and at91sam9g45_restart().

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
---
 drivers/power/reset/at91-reset.c | 26 ++++++++++++++++++--------
 1 file changed, 18 insertions(+), 8 deletions(-)

diff --git a/drivers/power/reset/at91-reset.c b/drivers/power/reset/at91-reset.c
index 3b1d566350f4..4e1961334e4d 100644
--- a/drivers/power/reset/at91-reset.c
+++ b/drivers/power/reset/at91-reset.c
@@ -61,6 +61,7 @@ struct at91_reset {
 	struct clk *sclk;
 	struct notifier_block nb;
 	u32 args;
+	u32 ramc_lpr;
 };
 
 /*
@@ -81,7 +82,7 @@ static int at91sam9260_restart(struct notifier_block *this, unsigned long mode,
 		"str	%2, [%0, #" __stringify(AT91_SDRAMC_TR) "]\n\t"
 
 		/* Power down SDRAM */
-		"str	%3, [%0, #" __stringify(AT91_SDRAMC_LPR) "]\n\t"
+		"str	%3, [%0, %5]\n\t"
 
 		/* Reset CPU */
 		"str	%4, [%1, #" __stringify(AT91_RSTC_CR) "]\n\t"
@@ -92,7 +93,8 @@ static int at91sam9260_restart(struct notifier_block *this, unsigned long mode,
 		  "r" (reset->rstc_base),
 		  "r" (1),
 		  "r" cpu_to_le32(AT91_SDRAMC_LPCB_POWER_DOWN),
-		  "r" (reset->args));
+		  "r" (reset->args),
+		  "r" (reset->ramc_lpr));
 
 	return NOTIFY_DONE;
 }
@@ -122,11 +124,11 @@ static int at91sam9g45_restart(struct notifier_block *this, unsigned long mode,
 		/* Disable SDRAM0 accesses */
 		"1:	str	%3, [%0, #" __stringify(AT91_DDRSDRC_RTR) "]\n\t"
 		/* Power down SDRAM0 */
-		"	str	%4, [%0, #" __stringify(AT91_DDRSDRC_LPR) "]\n\t"
+		"	str	%4, [%0, %6]\n\t"
 		/* Disable SDRAM1 accesses */
 		"	strne	%3, [%1, #" __stringify(AT91_DDRSDRC_RTR) "]\n\t"
 		/* Power down SDRAM1 */
-		"	strne	%4, [%1, #" __stringify(AT91_DDRSDRC_LPR) "]\n\t"
+		"	strne	%4, [%1, %6]\n\t"
 		/* Reset CPU */
 		"	str	%5, [%2, #" __stringify(AT91_RSTC_CR) "]\n\t"
 
@@ -137,7 +139,8 @@ static int at91sam9g45_restart(struct notifier_block *this, unsigned long mode,
 		  "r" (reset->rstc_base),
 		  "r" (1),
 		  "r" cpu_to_le32(AT91_DDRSDRC_LPCB_POWER_DOWN),
-		  "r" (reset->args)
+		  "r" (reset->args),
+		  "r" (reset->ramc_lpr)
 		: "r4");
 
 	return NOTIFY_DONE;
@@ -193,8 +196,14 @@ static void __init at91_reset_status(struct platform_device *pdev,
 }
 
 static const struct of_device_id at91_ramc_of_match[] = {
-	{ .compatible = "atmel,at91sam9260-sdramc", },
-	{ .compatible = "atmel,at91sam9g45-ddramc", },
+	{
+		.compatible = "atmel,at91sam9260-sdramc",
+		.data = (void *)AT91_SDRAMC_LPR,
+	},
+	{
+		.compatible = "atmel,at91sam9g45-ddramc",
+		.data = (void *)AT91_DDRSDRC_LPR,
+	},
 	{ /* sentinel */ }
 };
 
@@ -263,7 +272,8 @@ static int __init at91_reset_probe(struct platform_device *pdev)
 
 	if (!of_device_is_compatible(pdev->dev.of_node, "atmel,sama5d3-rstc")) {
 		/* we need to shutdown the ddr controller, so get ramc base */
-		for_each_matching_node(np, at91_ramc_of_match) {
+		for_each_matching_node_and_match(np, at91_ramc_of_match, &match) {
+			reset->ramc_lpr = (u32)match->data;
 			reset->ramc_base[idx] = of_iomap(np, 0);
 			if (!reset->ramc_base[idx]) {
 				dev_err(&pdev->dev, "Could not map ram controller address\n");
-- 
2.7.4

[PATCH 12/15] power: reset: at91-reset: make at91sam9g45_restart() generic

[Claudiu.Beznea]

Make at91sam9g45_restart() generic.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
---
 drivers/power/reset/at91-reset.c | 21 ++++++---------------
 1 file changed, 6 insertions(+), 15 deletions(-)

diff --git a/drivers/power/reset/at91-reset.c b/drivers/power/reset/at91-reset.c
index 4e1961334e4d..61433060d784 100644
--- a/drivers/power/reset/at91-reset.c
+++ b/drivers/power/reset/at91-reset.c
@@ -105,32 +105,23 @@ static int at91sam9g45_restart(struct notifier_block *this, unsigned long mode,
 	struct at91_reset *reset = container_of(this, struct at91_reset, nb);
 
 	asm volatile(
-		/*
-		 * Test wether we have a second RAM controller to care
-		 * about.
-		 *
-		 * First, test that we can dereference the virtual address.
-		 */
-		"cmp	%1, #0\n\t"
-		"beq	1f\n\t"
-
-		/* Then, test that the RAM controller is enabled */
-		"ldr	r4, [%1]\n\t"
-		"cmp	r4, #0\n\t"
-
 		/* Align to cache lines */
 		".balign 32\n\t"
 
 		/* Disable SDRAM0 accesses */
-		"1:	str	%3, [%0, #" __stringify(AT91_DDRSDRC_RTR) "]\n\t"
+		"	tst	%0, #0\n\t"
+		"	beq	1f\n\t"
+		"	str	%3, [%0, #" __stringify(AT91_DDRSDRC_RTR) "]\n\t"
 		/* Power down SDRAM0 */
 		"	str	%4, [%0, %6]\n\t"
 		/* Disable SDRAM1 accesses */
+		"1:	tst	%1, #0\n\t"
+		"	beq	2f\n\t"
 		"	strne	%3, [%1, #" __stringify(AT91_DDRSDRC_RTR) "]\n\t"
 		/* Power down SDRAM1 */
 		"	strne	%4, [%1, %6]\n\t"
 		/* Reset CPU */
-		"	str	%5, [%2, #" __stringify(AT91_RSTC_CR) "]\n\t"
+		"2:	str	%5, [%2, #" __stringify(AT91_RSTC_CR) "]\n\t"
 
 		"	b	.\n\t"
 		:
-- 
2.7.4

[PATCH 13/15] power: reset: at91-reset: keep only one reset function

[Claudiu.Beznea]

Keep only one reset function. With this, notifier_call member of
struct at91_reset_data could be removed.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
---
 drivers/power/reset/at91-reset.c | 52 +++-------------------------------------
 1 file changed, 3 insertions(+), 49 deletions(-)

diff --git a/drivers/power/reset/at91-reset.c b/drivers/power/reset/at91-reset.c
index 61433060d784..9c1b69f76a01 100644
--- a/drivers/power/reset/at91-reset.c
+++ b/drivers/power/reset/at91-reset.c
@@ -50,8 +50,6 @@ enum reset_type {
 };
 
 struct at91_reset_data {
-	int (*notifier_call)(struct notifier_block *this, unsigned long mode,
-			     void *cmd);
 	u32 args;
 };
 
@@ -69,38 +67,8 @@ struct at91_reset {
 * reset register it can be left driving the data bus and
 * killing the chance of a subsequent boot from NAND
 */
-static int at91sam9260_restart(struct notifier_block *this, unsigned long mode,
-			       void *cmd)
-{
-	struct at91_reset *reset = container_of(this, struct at91_reset, nb);
-
-	asm volatile(
-		/* Align to cache lines */
-		".balign 32\n\t"
-
-		/* Disable SDRAM accesses */
-		"str	%2, [%0, #" __stringify(AT91_SDRAMC_TR) "]\n\t"
-
-		/* Power down SDRAM */
-		"str	%3, [%0, %5]\n\t"
-
-		/* Reset CPU */
-		"str	%4, [%1, #" __stringify(AT91_RSTC_CR) "]\n\t"
-
-		"b	.\n\t"
-		:
-		: "r" (reset->ramc_base[0]),
-		  "r" (reset->rstc_base),
-		  "r" (1),
-		  "r" cpu_to_le32(AT91_SDRAMC_LPCB_POWER_DOWN),
-		  "r" (reset->args),
-		  "r" (reset->ramc_lpr));
-
-	return NOTIFY_DONE;
-}
-
-static int at91sam9g45_restart(struct notifier_block *this, unsigned long mode,
-			       void *cmd)
+static int at91_reset(struct notifier_block *this, unsigned long mode,
+		      void *cmd)
 {
 	struct at91_reset *reset = container_of(this, struct at91_reset, nb);
 
@@ -137,16 +105,6 @@ static int at91sam9g45_restart(struct notifier_block *this, unsigned long mode,
 	return NOTIFY_DONE;
 }
 
-static int sama5d3_restart(struct notifier_block *this, unsigned long mode,
-			   void *cmd)
-{
-	struct at91_reset *reset = container_of(this, struct at91_reset, nb);
-
-	writel(reset->args, reset->rstc_base);
-
-	return NOTIFY_DONE;
-}
-
 static void __init at91_reset_status(struct platform_device *pdev,
 				     void __iomem *base)
 {
@@ -199,22 +157,18 @@ static const struct of_device_id at91_ramc_of_match[] = {
 };
 
 static const struct at91_reset_data at91sam9260_reset_data = {
-	.notifier_call = at91sam9260_restart,
 	.args = AT91_RSTC_KEY | AT91_RSTC_PERRST | AT91_RSTC_PROCRST,
 };
 
 static const struct at91_reset_data at91sam9g45_reset_data = {
-	.notifier_call = at91sam9g45_restart,
 	.args = AT91_RSTC_KEY | AT91_RSTC_PERRST | AT91_RSTC_PROCRST,
 };
 
 static const struct at91_reset_data sama5d3_reset_data = {
-	.notifier_call = sama5d3_restart,
 	.args = AT91_RSTC_KEY | AT91_RSTC_PERRST | AT91_RSTC_PROCRST,
 };
 
 static const struct at91_reset_data samx7_reset_data = {
-	.notifier_call = sama5d3_restart,
 	.args = AT91_RSTC_KEY | AT91_RSTC_PROCRST,
 };
 
@@ -277,7 +231,7 @@ static int __init at91_reset_probe(struct platform_device *pdev)
 
 	match = of_match_node(at91_reset_of_match, pdev->dev.of_node);
 	reset_data = match->data;
-	reset->nb.notifier_call = reset_data->notifier_call;
+	reset->nb.notifier_call = at91_reset;
 	reset->nb.priority = 192;
 	reset->args = reset_data->args;
 
-- 
2.7.4

[PATCH 14/15] power: reset: at91-reset: get rid of at91_reset_data

[Claudiu.Beznea]

After refactoring struct at91_reset_data and
struct at91_reset_data at91sam9260_reset_data are not needed anymore.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
---
 drivers/power/reset/at91-reset.c | 37 +++++++++----------------------------
 1 file changed, 9 insertions(+), 28 deletions(-)

diff --git a/drivers/power/reset/at91-reset.c b/drivers/power/reset/at91-reset.c
index 9c1b69f76a01..537ccb180568 100644
--- a/drivers/power/reset/at91-reset.c
+++ b/drivers/power/reset/at91-reset.c
@@ -49,10 +49,6 @@ enum reset_type {
 	RESET_TYPE_ULP2		= 8,
 };
 
-struct at91_reset_data {
-	u32 args;
-};
-
 struct at91_reset {
 	void __iomem *rstc_base;
 	void __iomem *ramc_base[2];
@@ -156,42 +152,29 @@ static const struct of_device_id at91_ramc_of_match[] = {
 	{ /* sentinel */ }
 };
 
-static const struct at91_reset_data at91sam9260_reset_data = {
-	.args = AT91_RSTC_KEY | AT91_RSTC_PERRST | AT91_RSTC_PROCRST,
-};
-
-static const struct at91_reset_data at91sam9g45_reset_data = {
-	.args = AT91_RSTC_KEY | AT91_RSTC_PERRST | AT91_RSTC_PROCRST,
-};
-
-static const struct at91_reset_data sama5d3_reset_data = {
-	.args = AT91_RSTC_KEY | AT91_RSTC_PERRST | AT91_RSTC_PROCRST,
-};
-
-static const struct at91_reset_data samx7_reset_data = {
-	.args = AT91_RSTC_KEY | AT91_RSTC_PROCRST,
-};
-
 static const struct of_device_id at91_reset_of_match[] = {
 	{
 		.compatible = "atmel,at91sam9260-rstc",
-		.data = &at91sam9260_reset_data
+		.data = (void *)(AT91_RSTC_KEY | AT91_RSTC_PERRST |
+				 AT91_RSTC_PROCRST),
 	},
 	{
 		.compatible = "atmel,at91sam9g45-rstc",
-		.data = &at91sam9g45_reset_data
+		.data = (void *)(AT91_RSTC_KEY | AT91_RSTC_PERRST |
+				 AT91_RSTC_PROCRST)
 	},
 	{
 		.compatible = "atmel,sama5d3-rstc",
-		.data = &sama5d3_reset_data
+		.data = (void *)(AT91_RSTC_KEY | AT91_RSTC_PERRST |
+				 AT91_RSTC_PROCRST)
 	},
 	{
 		.compatible = "atmel,samx7-rstc",
-		.data = &samx7_reset_data
+		.data = (void *)(AT91_RSTC_KEY | AT91_RSTC_PROCRST)
 	},
 	{
 		.compatible = "microchip,sam9x60-rstc",
-		.data = &samx7_reset_data
+		.data = (void *)(AT91_RSTC_KEY | AT91_RSTC_PROCRST)
 	},
 	{ /* sentinel */ }
 };
@@ -199,7 +182,6 @@ MODULE_DEVICE_TABLE(of, at91_reset_of_match);
 
 static int __init at91_reset_probe(struct platform_device *pdev)
 {
-	const struct at91_reset_data *reset_data;
 	const struct of_device_id *match;
 	struct at91_reset *reset;
 	struct device_node *np;
@@ -230,10 +212,9 @@ static int __init at91_reset_probe(struct platform_device *pdev)
 	}
 
 	match = of_match_node(at91_reset_of_match, pdev->dev.of_node);
-	reset_data = match->data;
 	reset->nb.notifier_call = at91_reset;
 	reset->nb.priority = 192;
-	reset->args = reset_data->args;
+	reset->args = (u32)match->data;
 
 	reset->sclk = devm_clk_get(&pdev->dev, NULL);
 	if (IS_ERR(reset->sclk))
-- 
2.7.4

[PATCH 15/15] power: reset: at91-reset: handle nrst async for sam9x60

[Claudiu.Beznea]

Handle NRST asynchronously for SAM9X60 to avoid problem with fast drop of
VDDCORE on shutdown operations in the first 100 us after CPU is shutdown.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
---
 drivers/power/reset/at91-reset.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/power/reset/at91-reset.c b/drivers/power/reset/at91-reset.c
index 537ccb180568..3ff9d93a5226 100644
--- a/drivers/power/reset/at91-reset.c
+++ b/drivers/power/reset/at91-reset.c
@@ -35,6 +35,7 @@
 
 #define AT91_RSTC_MR	0x08		/* Reset Controller Mode Register */
 #define AT91_RSTC_URSTEN	BIT(0)		/* User Reset Enable */
+#define AT91_RSTC_URSTASYNC	BIT(2)		/* User Reset Asynchronous Control */
 #define AT91_RSTC_URSTIEN	BIT(4)		/* User Reset Interrupt Enable */
 #define AT91_RSTC_ERSTL		GENMASK(11, 8)	/* External Reset Length */
 
@@ -228,6 +229,13 @@ static int __init at91_reset_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, reset);
 
+	if (of_device_is_compatible(pdev->dev.of_node, "microchip,sam9x60-rstc")) {
+		u32 val = readl(reset->rstc_base + AT91_RSTC_MR);
+
+		writel(AT91_RSTC_KEY | AT91_RSTC_URSTASYNC | val,
+		       reset->rstc_base + AT91_RSTC_MR);
+	}
+
 	ret = register_restart_handler(&reset->nb);
 	if (ret) {
 		clk_disable_unprepare(reset->sclk);
-- 
2.7.4

Re: [PATCH 00/15] rework at91-reset driver

[Sebastian Reichel]

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Hi,

On Tue, Jan 21, 2020 at 10:03:29AM +0000, Claudiu.Beznea@microchip.com wrote:
> The following patches rework the at91-reset driver and solves
> the SAM9X60 VDDCORE fast drop in the first 100us after power down.

Thanks, queued to power-supply's for-next branch.

-- Sebastian

> Claudiu Beznea (15):
>   power: reset: at91-reset: introduce struct at91_reset
>   power: reset: at91-reset: add ramc_base[] to struct at91_reset
>   power: reset: at91-reset: add sclk to struct at91_reset
>   power: reset: at91-reset: add notifier block to struct at91_reset
>   power: reset: at91-reset: convert reset in pointer to struct
>     at91_reset
>   power: reset: at91-reset: pass rstc base address to
>     at91_reset_status()
>   power: reset: at91-reset: devm_kzalloc() for at91_reset data structure
>   power: reset: at91-reset: introduce struct at91_reset_data
>   power: reset: at91-reset: introduce args member in at91_reset_data
>   power: reset: at91-reset: use r4 as tmp argument
>   power: reset: at91-reset: introduce ramc_lpr to struct at91_reset
>   power: reset: at91-reset: make at91sam9g45_restart() generic
>   power: reset: at91-reset: keep only one reset function
>   power: reset: at91-reset: get rid of at91_reset_data
>   power: reset: at91-reset: handle nrst async for sam9x60
> 
>  drivers/power/reset/at91-reset.c | 190 +++++++++++++++++++--------------------
>  1 file changed, 94 insertions(+), 96 deletions(-)
> 
> -- 
> 2.7.4

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