[PATCH 0/2] arm: lpc32xx: restart: add support for soft reset

[PATCH 0/2] arm: lpc32xx: restart: add support for soft reset

[slemieux.tyco at gmail.com]

From: Sylvain Lemieux <slemieux@tycoint.com>

The LPC32xx provide the capability to perform a soft or hard reset;
a soft reset will no reset the external peripheral
(i.e. RESOUT_N output not asserted).

The default behavior (i.e. hard reset) remain unchanged.

Sylvain Lemieux (2):
  arm: lpc32xx: restart: add support for soft reset
  arm: lpc32xx: restart: support "cmd" from userspace

 arch/arm/mach-lpc32xx/common.c | 26 +++++++++++++++++++++++---
 1 file changed, 23 insertions(+), 3 deletions(-)

-- 
1.8.3.1

[PATCH 1/2] arm: lpc32xx: restart: add support for soft reset

[slemieux.tyco at gmail.com]

From: Sylvain Lemieux <slemieux@tycoint.com>

Add support for explicit soft reset using the reboot mode.

The default reboot mode behavior is unchanged;
you can specified the default reboot type in the board specific file
"DT_MACHINE_START" definition using the "reboot_mode" parameter.

Signed-off-by: Sylvain Lemieux <slemieux@tycoint.com>
---
 arch/arm/mach-lpc32xx/common.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/arch/arm/mach-lpc32xx/common.c b/arch/arm/mach-lpc32xx/common.c
index 716e83e..9eb9f22 100644
--- a/arch/arm/mach-lpc32xx/common.c
+++ b/arch/arm/mach-lpc32xx/common.c
@@ -200,9 +200,16 @@ void lpc23xx_restart(enum reboot_mode mode, const char *cmd)
 	__raw_writel(LPC32XX_CLKPWR_PWMCLK_WDOG_EN,
 		LPC32XX_CLKPWR_TIMER_CLK_CTRL);
 
-	/* Instant assert of RESETOUT_N with pulse length 1mS */
-	__raw_writel(13000, io_p2v(LPC32XX_WDTIM_BASE + 0x18));
-	__raw_writel(0x70, io_p2v(LPC32XX_WDTIM_BASE + 0xC));
+	if (mode == REBOOT_SOFT) {
+		/* Force match output active */
+		__raw_writel(0x01, io_p2v(LPC32XX_WDTIM_BASE + 0x14));
+		/* Enable internal reset on match output (RESOUT_N not asserted) */
+		__raw_writel(0x08, io_p2v(LPC32XX_WDTIM_BASE + 0xC));
+	} else {
+		/* Instant assert of RESETOUT_N with pulse length 1mS */
+		__raw_writel(13000, io_p2v(LPC32XX_WDTIM_BASE + 0x18));
+		__raw_writel(0x70, io_p2v(LPC32XX_WDTIM_BASE + 0xC));
+	}
 
 	/* Wait for watchdog to reset system */
 	while (1)
-- 
1.8.3.1

[PATCH 2/2] arm: lpc32xx: restart: support "cmd" from userspace

[slemieux.tyco at gmail.com]

From: Sylvain Lemieux <slemieux@tycoint.com>

Add the support to verify if a "cmd" is passed from the userspace program rebooting the system;
- if a valid "cmd" is available, it will be handle;
- If the received "cmd" is not supported, the default reboot mode is used.

Signed-off-by: Sylvain Lemieux <slemieux@tycoint.com>
---
 arch/arm/mach-lpc32xx/common.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/arch/arm/mach-lpc32xx/common.c b/arch/arm/mach-lpc32xx/common.c
index 9eb9f22..ba61839 100644
--- a/arch/arm/mach-lpc32xx/common.c
+++ b/arch/arm/mach-lpc32xx/common.c
@@ -196,6 +196,19 @@ void __init lpc32xx_map_io(void)
 
 void lpc23xx_restart(enum reboot_mode mode, const char *cmd)
 {
+	/*
+	 * Verify if a "cmd" passed from the userspace program rebooting
+	 * the system; if available, and handle it.
+	 * - For details, see the 'reboot' syscall in kernel/reboot.c
+	 * - If the received "cmd" is not supported, use the default mode.
+	 */
+	if (cmd) {
+		if (cmd[0] == 'h')
+			mode = REBOOT_HARD;
+		else if (cmd[0] == 's')
+			mode = REBOOT_SOFT;
+	}
+
 	/* Make sure WDT clocks are enabled */
 	__raw_writel(LPC32XX_CLKPWR_PWMCLK_WDOG_EN,
 		LPC32XX_CLKPWR_TIMER_CLK_CTRL);
-- 
1.8.3.1

[PATCH 0/2] arm: lpc32xx: restart: add support for soft reset

[Joachim Eastwood]

Hi Sylvain,

On 18 February 2016 at 22:35,  <slemieux.tyco@gmail.com> wrote:
> From: Sylvain Lemieux <slemieux@tycoint.com>
>
> The LPC32xx provide the capability to perform a soft or hard reset;
> a soft reset will no reset the external peripheral
> (i.e. RESOUT_N output not asserted).
>
> The default behavior (i.e. hard reset) remain unchanged.
>
> Sylvain Lemieux (2):
>   arm: lpc32xx: restart: add support for soft reset
>   arm: lpc32xx: restart: support "cmd" from userspace
>
>  arch/arm/mach-lpc32xx/common.c | 26 +++++++++++++++++++++++---
>  1 file changed, 23 insertions(+), 3 deletions(-)

Instead of adding more code to mach-lpc32xx could this code be moved
to the watchdog driver (pnx4008_wdt.c) ?
See register_restart_handler() and how it's used in other watchdog drivers.

Then maybe the restart hook in phy3250.c could be removed all together.


regards,
Joachim Eastwood