[PATCH v3 0/7] wdt: Add support for watchdogs on Kendryte K210

[PATCH v3 0/7] wdt: Add support for watchdogs on Kendryte K210

[Sean Anderson]

This series depends on
https://patchwork.ozlabs.org/project/uboot/patch/20200901195548.542737-1-seanga2 at gmail.com/

Changes in v3:
- Note dependency on "time: Fix get_ticks being non-monotonic"
- Add a few signed-off-bys which were sent for version 1

Changes in v2:
- Fix fls being off-by-one when compared to log_2_n_round_up
- Move watchdog enable to k210.dtsi as it does not depend on anything
  board-specific.

Sean Anderson (7):
  wdt: dw: Switch to using fls for log2
  wdt: dw: Switch to if(CONFIG()) instead of using #if
  wdt: dw: Fix clock rate being off by 1000
  wdt: dw: Enable the clock before using it
  wdt: dw: Free the clock on error
  riscv: Add watchdog bindings for the k210
  riscv: Enable watchdog for the k210

 arch/riscv/dts/k210.dtsi          |  1 -
 board/sipeed/maix/Kconfig         |  2 ++
 drivers/watchdog/designware_wdt.c | 38 +++++++++++++++++++------------
 3 files changed, 26 insertions(+), 15 deletions(-)

-- 
2.28.0

[PATCH v3 1/7] wdt: dw: Switch to using fls for log2

[Sean Anderson]

log_2_n_round_up is only found in arm. fls performs the same job and is
generic.

Signed-off-by: Sean Anderson <seanga2@gmail.com>
---

(no changes since v2)

Changes in v2:
- Fix fls being off-by-one when compared to log_2_n_round_up

 drivers/watchdog/designware_wdt.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/watchdog/designware_wdt.c b/drivers/watchdog/designware_wdt.c
index 12f09a7a39..f25c8d9ab3 100644
--- a/drivers/watchdog/designware_wdt.c
+++ b/drivers/watchdog/designware_wdt.c
@@ -9,7 +9,6 @@
 #include <reset.h>
 #include <wdt.h>
 #include <asm/io.h>
-#include <asm/utils.h>
 #include <linux/bitops.h>
 
 #define DW_WDT_CR	0x00
@@ -35,7 +34,7 @@ static int designware_wdt_settimeout(void __iomem *base, unsigned int clk_khz,
 	signed int i;
 
 	/* calculate the timeout range value */
-	i = log_2_n_round_up(timeout * clk_khz) - 16;
+	i = fls(timeout * clk_khz - 1) - 16;
 	i = clamp(i, 0, 15);
 
 	writel(i | (i << 4), base + DW_WDT_TORR);
-- 
2.28.0

[PATCH v3 1/7] wdt: dw: Switch to using fls for log2

[Simon Glass]

On Tue, 1 Sep 2020 at 14:08, Sean Anderson <seanga2@gmail.com> wrote:
>
> log_2_n_round_up is only found in arm. fls performs the same job and is
> generic.
>
> Signed-off-by: Sean Anderson <seanga2@gmail.com>
> ---
>
> (no changes since v2)
>
> Changes in v2:
> - Fix fls being off-by-one when compared to log_2_n_round_up
>
>  drivers/watchdog/designware_wdt.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
>

Reviewed-by: Simon Glass <sjg@chromium.org>

[PATCH v3 2/7] wdt: dw: Switch to if(CONFIG()) instead of using #if

[Sean Anderson]

This is preferred over #if because the compiler can check syntax even if
the feature is disabled. This cannot be used for CONFIG_CLK because
CONFIG_DW_WDT_CLOCK_KHZ is not defined on all platforms.

Signed-off-by: Sean Anderson <seanga2@gmail.com>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
---

(no changes since v1)

 drivers/watchdog/designware_wdt.c | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/drivers/watchdog/designware_wdt.c b/drivers/watchdog/designware_wdt.c
index f25c8d9ab3..49cf861d46 100644
--- a/drivers/watchdog/designware_wdt.c
+++ b/drivers/watchdog/designware_wdt.c
@@ -136,17 +136,17 @@ static int designware_wdt_probe(struct udevice *dev)
 	priv->clk_khz = CONFIG_DW_WDT_CLOCK_KHZ;
 #endif
 
-#if CONFIG_IS_ENABLED(DM_RESET)
-	struct reset_ctl_bulk resets;
+	if (CONFIG_IS_ENABLED(DM_RESET)) {
+		struct reset_ctl_bulk resets;
 
-	ret = reset_get_bulk(dev, &resets);
-	if (ret)
-		return ret;
+		ret = reset_get_bulk(dev, &resets);
+		if (ret)
+			return ret;
 
-	ret = reset_deassert_bulk(&resets);
-	if (ret)
-		return ret;
-#endif
+		ret = reset_deassert_bulk(&resets);
+		if (ret)
+			return ret;
+	}
 
 	/* reset to disable the watchdog */
 	return designware_wdt_stop(dev);
-- 
2.28.0

[PATCH v3 3/7] wdt: dw: Fix clock rate being off by 1000

[Sean Anderson]

The clock subsystem returns clock rates in Hz. We need to divide by 1000 so
the rate is in kHz.

Fixes: cf89ef8d10f240554541c20b2e1bdcdd58d1d7e6
Signed-off-by: Sean Anderson <seanga2@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
---

(no changes since v1)

 drivers/watchdog/designware_wdt.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/watchdog/designware_wdt.c b/drivers/watchdog/designware_wdt.c
index 49cf861d46..41866fa01b 100644
--- a/drivers/watchdog/designware_wdt.c
+++ b/drivers/watchdog/designware_wdt.c
@@ -129,7 +129,7 @@ static int designware_wdt_probe(struct udevice *dev)
 	if (ret)
 		return ret;
 
-	priv->clk_khz = clk_get_rate(&clk);
+	priv->clk_khz = clk_get_rate(&clk) / 1000;
 	if (!priv->clk_khz)
 		return -EINVAL;
 #else
-- 
2.28.0

[PATCH v3 4/7] wdt: dw: Enable the clock before using it

[Sean Anderson]

The watchdog won't work if the clock isn't enabled.

Fixes: cf89ef8d10f240554541c20b2e1bdcdd58d1d7e6
Signed-off-by: Sean Anderson <seanga2@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
---

(no changes since v1)

 drivers/watchdog/designware_wdt.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/watchdog/designware_wdt.c b/drivers/watchdog/designware_wdt.c
index 41866fa01b..e6f5437056 100644
--- a/drivers/watchdog/designware_wdt.c
+++ b/drivers/watchdog/designware_wdt.c
@@ -129,6 +129,10 @@ static int designware_wdt_probe(struct udevice *dev)
 	if (ret)
 		return ret;
 
+	ret = clk_enable(&clk);
+	if (ret)
+		return ret;
+
 	priv->clk_khz = clk_get_rate(&clk) / 1000;
 	if (!priv->clk_khz)
 		return -EINVAL;
-- 
2.28.0

[PATCH v3 5/7] wdt: dw: Free the clock on error

[Sean Anderson]

The clock subsystem requires that clk_free be called on clocks obtained via
clk_get_*.

Signed-off-by: Sean Anderson <seanga2@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
---

(no changes since v1)

 drivers/watchdog/designware_wdt.c | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/drivers/watchdog/designware_wdt.c b/drivers/watchdog/designware_wdt.c
index e6f5437056..189d555f29 100644
--- a/drivers/watchdog/designware_wdt.c
+++ b/drivers/watchdog/designware_wdt.c
@@ -131,11 +131,13 @@ static int designware_wdt_probe(struct udevice *dev)
 
 	ret = clk_enable(&clk);
 	if (ret)
-		return ret;
+		goto err;
 
 	priv->clk_khz = clk_get_rate(&clk) / 1000;
-	if (!priv->clk_khz)
-		return -EINVAL;
+	if (!priv->clk_khz) {
+		ret = -EINVAL;
+		goto err;
+	}
 #else
 	priv->clk_khz = CONFIG_DW_WDT_CLOCK_KHZ;
 #endif
@@ -145,15 +147,20 @@ static int designware_wdt_probe(struct udevice *dev)
 
 		ret = reset_get_bulk(dev, &resets);
 		if (ret)
-			return ret;
+			goto err;
 
 		ret = reset_deassert_bulk(&resets);
 		if (ret)
-			return ret;
+			goto err;
 	}
 
 	/* reset to disable the watchdog */
 	return designware_wdt_stop(dev);
+
+err:
+	if (CONFIG_IS_ENABLED(CLK))
+		clk_free(&clk);
+	return ret;
 }
 
 static const struct wdt_ops designware_wdt_ops = {
-- 
2.28.0

[PATCH v3 5/7] wdt: dw: Free the clock on error

[Sean Anderson]

On 9/1/20 4:07 PM, Sean Anderson wrote:
> The clock subsystem requires that clk_free be called on clocks obtained via
> clk_get_*.
> 
> Signed-off-by: Sean Anderson <seanga2@gmail.com>
> Reviewed-by: Simon Glass <sjg@chromium.org>
> ---
> 
> (no changes since v1)
> 
>  drivers/watchdog/designware_wdt.c | 17 ++++++++++++-----
>  1 file changed, 12 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/watchdog/designware_wdt.c b/drivers/watchdog/designware_wdt.c
> index e6f5437056..189d555f29 100644
> --- a/drivers/watchdog/designware_wdt.c
> +++ b/drivers/watchdog/designware_wdt.c
> @@ -131,11 +131,13 @@ static int designware_wdt_probe(struct udevice *dev)
>  
>  	ret = clk_enable(&clk);
>  	if (ret)
> -		return ret;
> +		goto err;
>  
>  	priv->clk_khz = clk_get_rate(&clk) / 1000;
> -	if (!priv->clk_khz)
> -		return -EINVAL;
> +	if (!priv->clk_khz) {
> +		ret = -EINVAL;
> +		goto err;
> +	}
>  #else
>  	priv->clk_khz = CONFIG_DW_WDT_CLOCK_KHZ;
>  #endif
> @@ -145,15 +147,20 @@ static int designware_wdt_probe(struct udevice *dev)
>  
>  		ret = reset_get_bulk(dev, &resets);
>  		if (ret)
> -			return ret;
> +			goto err;
>  
>  		ret = reset_deassert_bulk(&resets);
>  		if (ret)
> -			return ret;
> +			goto err;
>  	}
>  
>  	/* reset to disable the watchdog */
>  	return designware_wdt_stop(dev);
> +
> +err:
> +	if (CONFIG_IS_ENABLED(CLK))

This should be an #if. Found by running CI at

https://dev.azure.com/seanga2/u-boot/_build/results?buildId=26&view=logs&jobId=673723c4-497f-506b-4750-995fcb7877b8&j=673723c4-497f-506b-4750-995fcb7877b8&t=b5278753-2bf3-55ba-a142-eaf3481f5b3e

Will be fixed in v4.

--Sean

> +		clk_free(&clk);
> +	return ret;
>  }
>  
>  static const struct wdt_ops designware_wdt_ops = {
> 

[PATCH v3 6/7] riscv: Add watchdog bindings for the k210

[Sean Anderson]

This adds the necessary bindings. Most of them are already there.

Signed-off-by: Sean Anderson <seanga2@gmail.com>
Acked-by: Rick Chen <rick@andestech.com>
---

(no changes since v2)

Changes in v2:
- Move watchdog enable to k210.dtsi as it does not depend on anything
  board-specific.

 arch/riscv/dts/k210.dtsi | 1 -
 1 file changed, 1 deletion(-)

diff --git a/arch/riscv/dts/k210.dtsi b/arch/riscv/dts/k210.dtsi
index 2546c7d4e0..f70318cb12 100644
--- a/arch/riscv/dts/k210.dtsi
+++ b/arch/riscv/dts/k210.dtsi
@@ -425,7 +425,6 @@
 				interrupts = <21>;
 				clocks = <&sysclk K210_CLK_WDT0>;
 				resets = <&sysrst K210_RST_WDT0>;
-				status = "disabled";
 			};
 
 			wdt1: watchdog at 50410000 {
-- 
2.28.0

[PATCH v3 7/7] riscv: Enable watchdog for the k210

[Sean Anderson]

This enables the necessary config options.

Signed-off-by: Sean Anderson <seanga2@gmail.com>
---

Changes in v3:
- Note dependency on "time: Fix get_ticks being non-monotonic"
- Add a few signed-off-bys which were sent for version 1

 board/sipeed/maix/Kconfig | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/board/sipeed/maix/Kconfig b/board/sipeed/maix/Kconfig
index 0cdcd32adc..b9dac5a64e 100644
--- a/board/sipeed/maix/Kconfig
+++ b/board/sipeed/maix/Kconfig
@@ -44,4 +44,6 @@ config BOARD_SPECIFIC_OPTIONS
 	imply RESET_SYSCON
 	imply SYSRESET
 	imply SYSRESET_SYSCON
+	imply WDT
+	imply DESIGNWARE_WATCHDOG
 endif
-- 
2.28.0

[PATCH v3 7/7] riscv: Enable watchdog for the k210

[Simon Glass]

On Tue, 1 Sep 2020 at 14:08, Sean Anderson <seanga2@gmail.com> wrote:
>
> This enables the necessary config options.
>
> Signed-off-by: Sean Anderson <seanga2@gmail.com>
> ---
>
> Changes in v3:
> - Note dependency on "time: Fix get_ticks being non-monotonic"
> - Add a few signed-off-bys which were sent for version 1
>
>  board/sipeed/maix/Kconfig | 2 ++
>  1 file changed, 2 insertions(+)

Reviewed-by: Simon Glass <sjg@chromium.org>

[PATCH v3 0/7] wdt: Add support for watchdogs on Kendryte K210

[Sean Anderson]

On 9/1/20 4:07 PM, Sean Anderson wrote:
> This series depends on
> https://patchwork.ozlabs.org/project/uboot/patch/20200901195548.542737-1-seanga2 at gmail.com/

A note for those following along at home: after further investigation,
this series depends on [1]. It works with v1 of the above patch (as
linked), but if one applies v2 [2], it will panic without [1].

[1] https://patchwork.ozlabs.org/project/uboot/list/?series=200642
[2] https://patchwork.ozlabs.org/project/uboot/list/?series=200645

> 
> Changes in v3:
> - Note dependency on "time: Fix get_ticks being non-monotonic"
> - Add a few signed-off-bys which were sent for version 1
> 
> Changes in v2:
> - Fix fls being off-by-one when compared to log_2_n_round_up
> - Move watchdog enable to k210.dtsi as it does not depend on anything
>   board-specific.
> 
> Sean Anderson (7):
>   wdt: dw: Switch to using fls for log2
>   wdt: dw: Switch to if(CONFIG()) instead of using #if
>   wdt: dw: Fix clock rate being off by 1000
>   wdt: dw: Enable the clock before using it
>   wdt: dw: Free the clock on error
>   riscv: Add watchdog bindings for the k210
>   riscv: Enable watchdog for the k210
> 
>  arch/riscv/dts/k210.dtsi          |  1 -
>  board/sipeed/maix/Kconfig         |  2 ++
>  drivers/watchdog/designware_wdt.c | 38 +++++++++++++++++++------------
>  3 files changed, 26 insertions(+), 15 deletions(-)
>