[PATCH v6 0/6] ARM: at91: pm: add ULP1 mode support

[PATCH v6 0/6] ARM: at91: pm: add ULP1 mode support

[Wenyou Yang]

The ULP1 (Ultra Low-power mode 1) is introduced by SAMA5D2.

In order to achieve the lowest power consumption, in the ULP1 mode,
all the clocks are shut off, inclusive the embedded 12MHz RC oscillator.

The fast startup signal is used as a wake up source for ULP1 mode.
As soon as the wake up event is asserted, the embedded 12MHz RC
oscillator restarts automatically, which fast startup signal
to trigger the PMC to wake up the system from the ULP1 mode can be
configured via DT.

Changes in v6:
 - Add Acked-by tag.
 - Add specific sama5d2_pm_init() for SAMA5D2, which supports ULP1.
   It is called sama5d2_dt_device_init(). Instead of by reading
   the PMC version to check if it supports ULP1.
 - Add comment to describe the platform condition of calling
   at91_pm_ulp1_mode().
 - Update the commit log.
 - Add a new patch to support a new DT_MACHINE for SAMA5D2.

Changes in v5:
 - to improve the scalability, rework the DT expression part, use
   the child nodes to describe the wake-up input and its active level.
 - due to the DT property expression change, update the binding
   document.
 - due to the DT property expression change, update the fast restart
   node's property.

Changes in v4:
 - add Acked-by tag.
 - add fast_restart node to the DT file.

Changes in v3:
 - use 0 and 1, not string, to define the trigger active polarity.
 - update the property description.

Changes in v2:
 - fix label pm_exit to ulp_exit.
 - shorten the pmc-fast-startup property's name.
 - use the value property, instead of bool property for high
   or low triggered.
 - change the property name and property description.

Wenyou Yang (6):
  ARM: at91: sama5: Add a new DT_MACHINE for SAMA5D2
  ARM: at91: pm: Create a procedure for the ULP0 mode
  ARM: at91: pm: Add ULP1 mode support
  ARM: at91: pm: Configure PMC fast startup signals
  Documentation: atmel-pmc: Add DT bindings for fast startup
  ARM: at91/dt: sama5d2_xplained: Add fast_restart node

 .../devicetree/bindings/arm/atmel-pmc.txt          |  52 +++++++
 arch/arm/boot/dts/at91-sama5d2_xplained.dts        |  19 +++
 arch/arm/mach-at91/generic.h                       |   2 +
 arch/arm/mach-at91/pm.c                            |  83 ++++++++++-
 arch/arm/mach-at91/pm.h                            |   7 +
 arch/arm/mach-at91/pm_suspend.S                    | 160 ++++++++++++++++++---
 arch/arm/mach-at91/sama5.c                         |  26 +++-
 include/linux/clk/at91_pmc.h                       |  16 +++
 8 files changed, 338 insertions(+), 27 deletions(-)

-- 
2.7.4

[PATCH v6 1/6] ARM: at91: sama5: Add a new DT_MACHINE for SAMA5D2

[Wenyou Yang]

To support the SAMA5D2 specific pm_init function, add a new
DT_MACHINE for SAMA5D2.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
---

Changes in v6: None
Changes in v5: None
Changes in v4: None
Changes in v3: None
Changes in v2: None

 arch/arm/mach-at91/sama5.c | 25 +++++++++++++++++++++++--
 1 file changed, 23 insertions(+), 2 deletions(-)

diff --git a/arch/arm/mach-at91/sama5.c b/arch/arm/mach-at91/sama5.c
index 922b85f..2debfe2 100644
--- a/arch/arm/mach-at91/sama5.c
+++ b/arch/arm/mach-at91/sama5.c
@@ -59,7 +59,7 @@ static const struct at91_soc sama5_socs[] = {
 	{ /* sentinel */ },
 };
 
-static void __init sama5_dt_device_init(void)
+static void __init sama5_common_init(void)
 {
 	struct soc_device *soc;
 	struct device *soc_dev = NULL;
@@ -69,6 +69,11 @@ static void __init sama5_dt_device_init(void)
 		soc_dev = soc_device_to_device(soc);
 
 	of_platform_populate(NULL, of_default_bus_match_table, NULL, soc_dev);
+}
+
+static void __init sama5_dt_device_init(void)
+{
+	sama5_common_init();
 	sama5_pm_init();
 }
 
@@ -84,7 +89,6 @@ DT_MACHINE_START(sama5_dt, "Atmel SAMA5")
 MACHINE_END
 
 static const char *const sama5_alt_dt_board_compat[] __initconst = {
-	"atmel,sama5d2",
 	"atmel,sama5d4",
 	NULL
 };
@@ -95,3 +99,20 @@ DT_MACHINE_START(sama5_alt_dt, "Atmel SAMA5")
 	.dt_compat	= sama5_alt_dt_board_compat,
 	.l2c_aux_mask	= ~0UL,
 MACHINE_END
+
+static void __init sama5d2_dt_device_init(void)
+{
+	sama5_common_init();
+}
+
+static const char *const sama5d2_dt_board_compat[] __initconst = {
+	"atmel,sama5d2",
+	NULL
+};
+
+DT_MACHINE_START(sama5d2_dt, "Atmel SAMA5")
+	/* Maintainer: Atmel */
+	.init_machine	= sama5d2_dt_device_init,
+	.dt_compat	= sama5d2_dt_board_compat,
+	.l2c_aux_mask	= ~0UL,
+MACHINE_END
-- 
2.7.4

[PATCH v6 2/6] ARM: at91: pm: Create a procedure for the ULP0 mode

[Wenyou Yang]

To make the code more legible and prepare to add the ULP1 mode
support in the future, create a separate procedure for the ULP0 mode.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
---

Changes in v6:
 - Add Acked-by tag.

Changes in v5: None
Changes in v4: None
Changes in v3: None
Changes in v2: None

 arch/arm/mach-at91/pm_suspend.S | 65 +++++++++++++++++++++++++----------------
 1 file changed, 40 insertions(+), 25 deletions(-)

diff --git a/arch/arm/mach-at91/pm_suspend.S b/arch/arm/mach-at91/pm_suspend.S
index a25defd..5fcffdc 100644
--- a/arch/arm/mach-at91/pm_suspend.S
+++ b/arch/arm/mach-at91/pm_suspend.S
@@ -107,7 +107,7 @@ ENTRY(at91_pm_suspend_in_sram)
 
 	ldr	r0, .pm_mode
 	tst	r0, #AT91_PM_SLOW_CLOCK
-	beq	skip_disable_main_clock
+	beq	standby_mode
 
 	ldr	pmc, .pmc_base
 
@@ -131,32 +131,13 @@ ENTRY(at91_pm_suspend_in_sram)
 	orr	tmp1, tmp1, #(1 << 29)		/* bit 29 always set */
 	str	tmp1, [pmc, #AT91_CKGR_PLLAR]
 
-	/* Turn off the main oscillator */
-	ldr	tmp1, [pmc, #AT91_CKGR_MOR]
-	bic	tmp1, tmp1, #AT91_PMC_MOSCEN
-	orr	tmp1, tmp1, #AT91_PMC_KEY
-	str	tmp1, [pmc, #AT91_CKGR_MOR]
-
-skip_disable_main_clock:
-	ldr	pmc, .pmc_base
-
-	/* Wait for interrupt */
-	at91_cpu_idle
-
-	ldr	r0, .pm_mode
-	tst	r0, #AT91_PM_SLOW_CLOCK
-	beq	skip_enable_main_clock
+ulp0_mode:
+	bl	at91_pm_ulp0_mode
+	b	ulp_exit
 
+ulp_exit:
 	ldr	pmc, .pmc_base
 
-	/* Turn on the main oscillator */
-	ldr	tmp1, [pmc, #AT91_CKGR_MOR]
-	orr	tmp1, tmp1, #AT91_PMC_MOSCEN
-	orr	tmp1, tmp1, #AT91_PMC_KEY
-	str	tmp1, [pmc, #AT91_CKGR_MOR]
-
-	wait_moscrdy
-
 	/* Restore PLLA setting */
 	ldr	tmp1, .saved_pllar
 	str	tmp1, [pmc, #AT91_CKGR_PLLAR]
@@ -177,7 +158,15 @@ skip_disable_main_clock:
 
 	wait_mckrdy
 
-skip_enable_main_clock:
+	b	pm_exit
+
+standby_mode:
+	ldr	pmc, .pmc_base
+
+	/* Wait for interrupt */
+	at91_cpu_idle
+
+pm_exit:
 	/* Exit the self-refresh mode */
 	mov	r0, #SRAMC_SELF_FRESH_EXIT
 	bl	at91_sramc_self_refresh
@@ -311,6 +300,32 @@ exit_sramc_sf:
 	mov	pc, lr
 ENDPROC(at91_sramc_self_refresh)
 
+/*
+ * void at91_pm_ulp0_mode(void)
+ */
+ENTRY(at91_pm_ulp0_mode)
+	ldr	pmc, .pmc_base
+
+	/* Turn off the crystal oscillator */
+	ldr	tmp1, [pmc, #AT91_CKGR_MOR]
+	bic	tmp1, tmp1, #AT91_PMC_MOSCEN
+	orr	tmp1, tmp1, #AT91_PMC_KEY
+	str	tmp1, [pmc, #AT91_CKGR_MOR]
+
+	/* Wait for interrupt */
+	at91_cpu_idle
+
+	/* Turn on the crystal oscillator */
+	ldr	tmp1, [pmc, #AT91_CKGR_MOR]
+	orr	tmp1, tmp1, #AT91_PMC_MOSCEN
+	orr	tmp1, tmp1, #AT91_PMC_KEY
+	str	tmp1, [pmc, #AT91_CKGR_MOR]
+
+	wait_moscrdy
+
+	mov	pc, lr
+ENDPROC(at91_pm_ulp0_mode)
+
 .pmc_base:
 	.word 0
 .sramc_base:
-- 
2.7.4

[PATCH v6 3/6] ARM: at91: pm: Add ULP1 mode support

[Wenyou Yang]

In the ULP1 mode, in order to achieve the lowest power consumption
with the system in retention mode and be able to resume on the wake
up events, all the clocks are shut off, inclusive the embedded 12MHz
RC oscillator, and the number of wake up sources is limited as well.
When the wake up event is asserted, the embedded 12MHz RC oscillator
restarts automatically.

The ULP1 (Ultra Low-power mode 1) is introduced by SAMA5D2.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
---

Changes in v6:
 - Add specific sama5d2_pm_init() for SAMA5D2, which supports ULP1.
   It is called sama5d2_dt_device_init(). Instead of by reading
   the PMC version to check if it supports ULP1.
 - Add comment to describe the platform condition of calling
   at91_pm_ulp1_mode().
 - Update the commit log.

Changes in v5: None
Changes in v4: None
Changes in v3: None
Changes in v2:
 - fix label pm_exit to ulp_exit.

 arch/arm/mach-at91/generic.h    |  2 +
 arch/arm/mach-at91/pm.c         | 18 +++++++-
 arch/arm/mach-at91/pm.h         |  7 +++
 arch/arm/mach-at91/pm_suspend.S | 99 +++++++++++++++++++++++++++++++++++++++++
 arch/arm/mach-at91/sama5.c      |  1 +
 include/linux/clk/at91_pmc.h    |  2 +
 6 files changed, 127 insertions(+), 2 deletions(-)

diff --git a/arch/arm/mach-at91/generic.h b/arch/arm/mach-at91/generic.h
index 28ca57a..d716164 100644
--- a/arch/arm/mach-at91/generic.h
+++ b/arch/arm/mach-at91/generic.h
@@ -17,12 +17,14 @@ extern void __init at91sam9260_pm_init(void);
 extern void __init at91sam9g45_pm_init(void);
 extern void __init at91sam9x5_pm_init(void);
 extern void __init sama5_pm_init(void);
+extern void __init sama5d2_pm_init(void);
 #else
 static inline void __init at91rm9200_pm_init(void) { }
 static inline void __init at91sam9260_pm_init(void) { }
 static inline void __init at91sam9g45_pm_init(void) { }
 static inline void __init at91sam9x5_pm_init(void) { }
 static inline void __init sama5_pm_init(void) { }
+static inline void __init sama5d2_pm_init(void) { }
 #endif
 
 #endif /* _AT91_GENERIC_H */
diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c
index f062701..dad412f 100644
--- a/arch/arm/mach-at91/pm.c
+++ b/arch/arm/mach-at91/pm.c
@@ -36,6 +36,9 @@
 #include "generic.h"
 #include "pm.h"
 
+#define ULP0_MODE	0x00
+#define ULP1_MODE	0x11
+
 static void __iomem *pmc;
 
 /*
@@ -52,6 +55,7 @@ extern void at91_pinctrl_gpio_resume(void);
 static struct {
 	unsigned long uhp_udp_mask;
 	int memctrl;
+	u32 ulp_mode;
 } at91_pm_data;
 
 void __iomem *at91_ramc_base[2];
@@ -141,8 +145,11 @@ static void at91_pm_suspend(suspend_state_t state)
 {
 	unsigned int pm_data = at91_pm_data.memctrl;
 
-	pm_data |= (state == PM_SUSPEND_MEM) ?
-				AT91_PM_MODE(AT91_PM_SLOW_CLOCK) : 0;
+	if (state == PM_SUSPEND_MEM) {
+		pm_data |= AT91_PM_MODE(AT91_PM_SLOW_CLOCK);
+		if (at91_pm_data.ulp_mode == ULP1_MODE)
+			pm_data |= AT91_PM_ULP(AT91_PM_ULP1_MODE);
+	}
 
 	flush_cache_all();
 	outer_disable();
@@ -498,3 +505,10 @@ void __init sama5_pm_init(void)
 	at91_pm_data.memctrl = AT91_MEMCTRL_DDRSDR;
 	at91_pm_init(NULL);
 }
+
+void __init sama5d2_pm_init(void)
+{
+	sama5_pm_init();
+
+	at91_pm_data.ulp_mode = ULP1_MODE;
+}
diff --git a/arch/arm/mach-at91/pm.h b/arch/arm/mach-at91/pm.h
index 3fcf881..2e76745 100644
--- a/arch/arm/mach-at91/pm.h
+++ b/arch/arm/mach-at91/pm.h
@@ -39,4 +39,11 @@ extern void __iomem *at91_ramc_base[];
 
 #define	AT91_PM_SLOW_CLOCK	0x01
 
+#define AT91_PM_ULP_OFFSET	5
+#define AT91_PM_ULP_MASK	0x03
+#define AT91_PM_ULP(x)		(((x) & AT91_PM_ULP_MASK) << AT91_PM_ULP_OFFSET)
+
+#define AT91_PM_ULP0_MODE	0x00
+#define AT91_PM_ULP1_MODE	0x01
+
 #endif
diff --git a/arch/arm/mach-at91/pm_suspend.S b/arch/arm/mach-at91/pm_suspend.S
index 5fcffdc..de45575 100644
--- a/arch/arm/mach-at91/pm_suspend.S
+++ b/arch/arm/mach-at91/pm_suspend.S
@@ -41,6 +41,15 @@ tmp2	.req	r5
 	.endm
 
 /*
+ * Wait for main oscillator selection is done
+ */
+	.macro wait_moscsels
+1:	ldr	tmp1, [pmc, #AT91_PMC_SR]
+	tst	tmp1, #AT91_PMC_MOSCSELS
+	beq	1b
+	.endm
+
+/*
  * Wait until PLLA has locked.
  */
 	.macro wait_pllalock
@@ -101,6 +110,10 @@ ENTRY(at91_pm_suspend_in_sram)
 	and	r0, r0, #AT91_PM_MODE_MASK
 	str	r0, .pm_mode
 
+	lsr	r0, r3, #AT91_PM_ULP_OFFSET
+	and	r0, r0, #AT91_PM_ULP_MASK
+	str	r0, .ulp_mode
+
 	/* Active the self-refresh mode */
 	mov	r0, #SRAMC_SELF_FRESH_ACTIVE
 	bl	at91_sramc_self_refresh
@@ -131,6 +144,13 @@ ENTRY(at91_pm_suspend_in_sram)
 	orr	tmp1, tmp1, #(1 << 29)		/* bit 29 always set */
 	str	tmp1, [pmc, #AT91_CKGR_PLLAR]
 
+	ldr	r0, .ulp_mode
+	tst	r0, #AT91_PM_ULP1_MODE
+	beq	ulp0_mode
+
+	bl	at91_pm_ulp1_mode
+	b	ulp_exit
+
 ulp0_mode:
 	bl	at91_pm_ulp0_mode
 	b	ulp_exit
@@ -326,6 +346,83 @@ ENTRY(at91_pm_ulp0_mode)
 	mov	pc, lr
 ENDPROC(at91_pm_ulp0_mode)
 
+/**
+ * void at91_pm_ulp1_mode(void)
+ * Note: This procedure only applies on the platform which uses
+ * the external crystal oscillator as a main clock source.
+ */
+ENTRY(at91_pm_ulp1_mode)
+	ldr	pmc, .pmc_base
+
+	/* Switch the main clock source to 12-MHz RC oscillator */
+	ldr	tmp1, [pmc, #AT91_CKGR_MOR]
+	bic	tmp1, tmp1, #AT91_PMC_MOSCSEL
+	bic	tmp1, tmp1, #AT91_PMC_KEY_MASK
+	orr	tmp1, tmp1, #AT91_PMC_KEY
+	str	tmp1, [pmc, #AT91_CKGR_MOR]
+
+	wait_moscsels
+
+	/* Disable the crystal oscillator */
+	ldr	tmp1, [pmc, #AT91_CKGR_MOR]
+	bic	tmp1, tmp1, #AT91_PMC_MOSCEN
+	bic	tmp1, tmp1, #AT91_PMC_KEY_MASK
+	orr	tmp1, tmp1, #AT91_PMC_KEY
+	str	tmp1, [pmc, #AT91_CKGR_MOR]
+
+	/* Switch the master clock source to main clock */
+	ldr	tmp1, [pmc, #AT91_PMC_MCKR]
+	bic	tmp1, tmp1, #AT91_PMC_CSS
+	orr	tmp1, tmp1, #AT91_PMC_CSS_MAIN
+	str	tmp1, [pmc, #AT91_PMC_MCKR]
+
+	wait_mckrdy
+
+	/* Enter the ULP1 mode by set WAITMODE bit in CKGR_MOR */
+	ldr	tmp1, [pmc, #AT91_CKGR_MOR]
+	orr	tmp1, tmp1, #AT91_PMC_WAITMODE
+	bic	tmp1, tmp1, #AT91_PMC_KEY_MASK
+	orr	tmp1, tmp1, #AT91_PMC_KEY
+	str	tmp1, [pmc, #AT91_CKGR_MOR]
+
+	wait_mckrdy
+
+	/* Enable the crystal oscillator */
+	ldr	tmp1, [pmc, #AT91_CKGR_MOR]
+	orr	tmp1, tmp1, #AT91_PMC_MOSCEN
+	bic	tmp1, tmp1, #AT91_PMC_KEY_MASK
+	orr	tmp1, tmp1, #AT91_PMC_KEY
+	str	tmp1, [pmc, #AT91_CKGR_MOR]
+
+	wait_moscrdy
+
+	/* Switch the master clock source to slow clock */
+	ldr	tmp1, [pmc, #AT91_PMC_MCKR]
+	bic	tmp1, tmp1, #AT91_PMC_CSS
+	str	tmp1, [pmc, #AT91_PMC_MCKR]
+
+	wait_mckrdy
+
+	/* Switch main clock source to crystal oscillator */
+	ldr	tmp1, [pmc, #AT91_CKGR_MOR]
+	orr	tmp1, tmp1, #AT91_PMC_MOSCSEL
+	bic	tmp1, tmp1, #AT91_PMC_KEY_MASK
+	orr	tmp1, tmp1, #AT91_PMC_KEY
+	str	tmp1, [pmc, #AT91_CKGR_MOR]
+
+	wait_moscsels
+
+	/* Switch the master clock source to main clock */
+	ldr	tmp1, [pmc, #AT91_PMC_MCKR]
+	bic	tmp1, tmp1, #AT91_PMC_CSS
+	orr	tmp1, tmp1, #AT91_PMC_CSS_MAIN
+	str	tmp1, [pmc, #AT91_PMC_MCKR]
+
+	wait_mckrdy
+
+	mov	pc, lr
+ENDPROC(at91_pm_ulp1_mode)
+
 .pmc_base:
 	.word 0
 .sramc_base:
@@ -336,6 +433,8 @@ ENDPROC(at91_pm_ulp0_mode)
 	.word 0
 .pm_mode:
 	.word 0
+.ulp_mode:
+	.word 0
 .saved_mckr:
 	.word 0
 .saved_pllar:
diff --git a/arch/arm/mach-at91/sama5.c b/arch/arm/mach-at91/sama5.c
index 2debfe2..5bc3fc8 100644
--- a/arch/arm/mach-at91/sama5.c
+++ b/arch/arm/mach-at91/sama5.c
@@ -103,6 +103,7 @@ MACHINE_END
 static void __init sama5d2_dt_device_init(void)
 {
 	sama5_common_init();
+	sama5d2_pm_init();
 }
 
 static const char *const sama5d2_dt_board_compat[] __initconst = {
diff --git a/include/linux/clk/at91_pmc.h b/include/linux/clk/at91_pmc.h
index 17f413b..cec6cc3 100644
--- a/include/linux/clk/at91_pmc.h
+++ b/include/linux/clk/at91_pmc.h
@@ -47,8 +47,10 @@
 #define	AT91_CKGR_MOR		0x20			/* Main Oscillator Register [not on SAM9RL] */
 #define		AT91_PMC_MOSCEN		(1    <<  0)		/* Main Oscillator Enable */
 #define		AT91_PMC_OSCBYPASS	(1    <<  1)		/* Oscillator Bypass */
+#define		AT91_PMC_WAITMODE	(1    <<  2)		/* Wait Mode Command */
 #define		AT91_PMC_MOSCRCEN	(1    <<  3)		/* Main On-Chip RC Oscillator Enable [some SAM9] */
 #define		AT91_PMC_OSCOUNT	(0xff <<  8)		/* Main Oscillator Start-up Time */
+#define		AT91_PMC_KEY_MASK	(0xff << 16)
 #define		AT91_PMC_KEY		(0x37 << 16)		/* MOR Writing Key */
 #define		AT91_PMC_MOSCSEL	(1    << 24)		/* Main Oscillator Selection [some SAM9] */
 #define		AT91_PMC_CFDEN		(1    << 25)		/* Clock Failure Detector Enable [some SAM9] */
-- 
2.7.4

[PATCH v6 4/6] ARM: at91: pm: Configure PMC fast startup signals

[Wenyou Yang]

The fast startup signal is used as wake up sources for ULP1 mode.
As soon as a fast startup signal is asserted, the embedded 12 MHz
RC oscillator restarts automatically.

This patch is to configure the fast startup signals, which signal
is enabled to trigger the PMC to wake up the system from ULP1 mode
should be configured via the DT.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
---

Changes in v6: None
Changes in v5:
 - to improve the scalability, rework the DT expression part, use
   the child nodes to describe the wake-up input and its active level.

Changes in v4: None
Changes in v3:
 - use 0 and 1, not string, to define the trigger active polarity.

Changes in v2:
 - shorten the pmc-fast-startup property's name.
 - use the value property, instead of bool property for high
   or low triggered.

 arch/arm/mach-at91/pm.c      | 65 ++++++++++++++++++++++++++++++++++++++++++++
 include/linux/clk/at91_pmc.h | 14 ++++++++++
 2 files changed, 79 insertions(+)

diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c
index dad412f..e451d34 100644
--- a/arch/arm/mach-at91/pm.c
+++ b/arch/arm/mach-at91/pm.c
@@ -24,6 +24,8 @@
 #include <linux/platform_device.h>
 #include <linux/io.h>
 #include <linux/clk/at91_pmc.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
 
 #include <asm/irq.h>
 #include <linux/atomic.h>
@@ -459,6 +461,68 @@ static void __init at91_pm_init(void (*pm_idle)(void))
 		pr_info("AT91: PM not supported, due to no SRAM allocated\n");
 }
 
+static int __init at91_pmc_fast_startup_init(void)
+{
+	struct device_node *np, *cnp;
+	struct regmap *regmap;
+	u32 input, input_mask;
+	u32 mode = 0, polarity = 0;
+
+	np = of_find_compatible_node(NULL, NULL,
+				     "atmel,sama5d2-pmc-fast-startup");
+	if (!np)
+		return -ENODEV;
+
+	regmap = syscon_node_to_regmap(of_get_parent(np));
+	if (IS_ERR(regmap)) {
+		pr_info("AT91: failed to find PMC fast startup node\n");
+		return PTR_ERR(regmap);
+	}
+
+	for_each_child_of_node(np, cnp) {
+		if (of_property_read_u32(cnp, "reg", &input)) {
+			pr_warn("AT91: reg property is missing for %s\n",
+				cnp->full_name);
+			continue;
+		}
+
+		input_mask = 1 << input;
+		if (!(input_mask & AT91_PMC_FS_INPUT_MASK)) {
+			pr_warn("AT91: wake-up input %d out of range\n", input);
+			continue;
+		}
+		mode |= input_mask;
+
+		if (of_property_read_bool(cnp, "atmel,wakeup-active-high"))
+			polarity |= input_mask;
+	}
+
+	if (of_property_read_bool(np, "atmel,wakeup-rtc-timer"))
+		mode |= AT91_PMC_RTCAL;
+
+	if (of_property_read_bool(np, "atmel,wakeup-usb-resume"))
+		mode |= AT91_PMC_USBAL;
+
+	if (of_property_read_bool(np, "atmel,wakeup-sdmmc-cd"))
+		mode |= AT91_PMC_SDMMC_CD;
+
+	if (of_property_read_bool(np, "atmel,wakeup-rxlp-match"))
+		mode |= AT91_PMC_RXLP_MCE;
+
+	if (of_property_read_bool(np, "atmel,wakeup-acc-comparison"))
+		mode |= AT91_PMC_ACC_CE;
+
+	pr_debug("AT91: mode = 0x%x, ploarity = 0%x\n", mode, polarity);
+
+	regmap_write(regmap, AT91_PMC_FSMR, mode);
+
+	regmap_write(regmap, AT91_PMC_FSPR, polarity);
+
+	of_node_put(np);
+
+	return 0;
+}
+
 void __init at91rm9200_pm_init(void)
 {
 	at91_dt_ramc();
@@ -511,4 +575,5 @@ void __init sama5d2_pm_init(void)
 	sama5_pm_init();
 
 	at91_pm_data.ulp_mode = ULP1_MODE;
+	at91_pmc_fast_startup_init();
 }
diff --git a/include/linux/clk/at91_pmc.h b/include/linux/clk/at91_pmc.h
index cec6cc3..08a55f2 100644
--- a/include/linux/clk/at91_pmc.h
+++ b/include/linux/clk/at91_pmc.h
@@ -157,6 +157,20 @@
 #define		AT91_PMC_GCKRDY		(1 << 24)		/* Generated Clocks */
 #define	AT91_PMC_IMR		0x6c			/* Interrupt Mask Register */
 
+#define AT91_PMC_FSMR		0x70		/* Fast Startup Mode Register */
+#define AT91_PMC_FSTT(n)	(0x1 << n)
+#define AT91_PMC_RTCAL		BIT(17)		/* RTC Alarm Enable */
+#define AT91_PMC_USBAL		BIT(18)		/* USB Resume Enable */
+#define AT91_PMC_SDMMC_CD	BIT(19)		/* SDMMC Card Detect Enable */
+#define AT91_PMC_LPM		BIT(20)		/* Low-power Mode */
+#define AT91_PMC_RXLP_MCE	BIT(24)		/* Backup UART Receive Enable */
+#define AT91_PMC_ACC_CE		BIT(25)		/* ACC Enable */
+
+#define AT91_PMC_FSPR		0x74		/* Fast Startup Polarity Reg */
+#define AT91_PMC_FSTP(n)	(0x1 << n)
+
+#define AT91_PMC_FS_INPUT_MASK  0x7ff
+
 #define AT91_PMC_PLLICPR	0x80			/* PLL Charge Pump Current Register */
 
 #define AT91_PMC_PROT		0xe4			/* Write Protect Mode Register [some SAM9] */
-- 
2.7.4

[PATCH v6 5/6] Documentation: atmel-pmc: Add DT bindings for fast startup

[Wenyou Yang]

Add DT bindings to configurate the PMC_FSMR and PMC_FSPR registers
to trigger a fast restart signal to PMC.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Acked-by: Rob Herring <robh+dt@kernel.org>
---

Changes in v6: None
Changes in v5:
 - due to the DT property expression change, update the binding
   document.

Changes in v4:
 - add Acked-by tag.

Changes in v3:
 - update the property description.

Changes in v2:
 - change the property name and property description.

 .../devicetree/bindings/arm/atmel-pmc.txt          | 52 ++++++++++++++++++++++
 1 file changed, 52 insertions(+)

diff --git a/Documentation/devicetree/bindings/arm/atmel-pmc.txt b/Documentation/devicetree/bindings/arm/atmel-pmc.txt
index 795cc78..76fdc66 100644
--- a/Documentation/devicetree/bindings/arm/atmel-pmc.txt
+++ b/Documentation/devicetree/bindings/arm/atmel-pmc.txt
@@ -12,3 +12,55 @@ Examples:
 		compatible = "atmel,at91rm9200-pmc";
 		reg = <0xfffffc00 0x100>;
 	};
+
+PMC Fast Startup Signals
+
+The PMC Fast Start Signals are used as the wake up source to trigger the PMC
+to wake up the system from the ULP1 mode.
+
+required properties:
+- compatible: should be "atmel,sama5d2-pmc-fast-startup".
+
+optional properties:
+- atmel,wakeup-rtc-timer: boolean to enable RTC alarm wake-up.
+- atmel,wakeup-usb-resume: boolean to enable USB resume wake-up.
+- atmel,wakeup-sdmmc-cd: boolean to enable SDMMC card detect wake-up.
+- atmel,wakeup-rxlp-match: boolean to enable RXLP matching condition wake-up.
+- atmel,wakeup-acc-comparison: boolean to enable ACC comparison wake-up.
+
+The node contains child nodes for each wake-up input pin that the platform uses.
+
+Input nodes
+
+Required properties:
+- reg: should contain the wake-up input index [0 - 10], to enable
+  the corresponding wake-up input.
+
+Optional properties:
+- atmel,wakeup-active-high: boolean to declare the corresponding wake-up
+  input described by the child be active high.
+  The default is to be active low.
+
+Example:
+
+	pmc: pmc@f0014000 {
+		compatible = "atmel,sama5d2-pmc";
+		reg = <0xf0014000 0x160>;
+
+		pmc_fast_restart {
+			compatible = "atmel,sama5d2-pmc-fast-startup";
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			atmel,wakeup-rtc-timer;
+
+			wkpin: input@0 {
+				reg = <0>;
+			};
+
+			gmac_wol: input@10 {
+				reg = <10>;
+				atmel,wakeup-active-high;
+			};
+		};
+	};
-- 
2.7.4

[PATCH v6 6/6] ARM: at91/dt: sama5d2_xplained: Add fast_restart node

[Wenyou Yang]

Add fast_restart node as a pmc's child node to support fast startup
signal configuration.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
---

Changes in v6:
 - Add a new patch to support a new DT_MACHINE for SAMA5D2.

Changes in v5:
 - due to the DT property expression change, update the fast restart
   node's property.

Changes in v4:
 - add fast_restart node to the DT file.

Changes in v3: None
Changes in v2: None

 arch/arm/boot/dts/at91-sama5d2_xplained.dts | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/arch/arm/boot/dts/at91-sama5d2_xplained.dts b/arch/arm/boot/dts/at91-sama5d2_xplained.dts
index eb4f1ac..714fd82 100644
--- a/arch/arm/boot/dts/at91-sama5d2_xplained.dts
+++ b/arch/arm/boot/dts/at91-sama5d2_xplained.dts
@@ -110,6 +110,25 @@
 		};
 
 		apb {
+			pmc: pmc@f0014000 {
+				pmc_fast_restart {
+					compatible = "atmel,sama5d2-pmc-fast-startup";
+					#address-cells = <1>;
+					#size-cells = <0>;
+
+					atmel,wakeup-rtc-timer;
+
+					wkpin: input@0 {
+						reg = <0>;
+					};
+
+					gmac_wol: input@10 {
+						reg = <10>;
+						atmel,wakeup-active-high;
+					};
+				};
+			};
+
 			spi0: spi@f8000000 {
 				pinctrl-names = "default";
 				pinctrl-0 = <&pinctrl_spi0_default>;
-- 
2.7.4