[PATCH 0/3] AT91 PM improvements

[PATCH 0/3] AT91 PM improvements

[Claudiu Beznea]

Hi,

This series adds ULP0 fast mode intended to reduce the suspend/resume
time in the detriment of power consumption (patch 1/3).
Along with this patch 2/3 adds code to avoid requesting a PM mode
not available on platforms not supporting it.
Patch 3/3 decrements a device_node refcount after its usage.

Thank you,
Claudiu Beznea

Claudiu Beznea (3):
  ARM: at91: pm: add support for ulp0 fast mode
  ARM: at91: pm: add per soc validation of pm modes
  ARM: at91: pm: put node after its usage

 arch/arm/mach-at91/at91rm9200.c | 10 +++++-
 arch/arm/mach-at91/at91sam9.c   |  9 ++++-
 arch/arm/mach-at91/generic.h    | 20 +++++------
 arch/arm/mach-at91/pm.c         | 79 +++++++++++++++++++++++++++++++++++------
 arch/arm/mach-at91/pm.h         |  5 +--
 arch/arm/mach-at91/pm_suspend.S | 41 ++++++++++++++++++---
 arch/arm/mach-at91/sam9x60.c    | 11 +++++-
 arch/arm/mach-at91/sama5.c      | 21 +++++++++--
 8 files changed, 165 insertions(+), 31 deletions(-)

-- 
2.7.4

[PATCH 1/3] ARM: at91: pm: add support for ulp0 fast mode

[Claudiu Beznea]

ULP0 fast improves suspend/resume time with few milliseconds the drawback
being the power consumption. The mean values measured for suspend/resume
time are as follows (measured on SAMA5D2 Xplained board), ULP0 compared
with ULP0 fast:
- ulp0 fast: suspend time: 169 ms, resume time: 216 ms
- ulp0     : suspend time: 197 ms, resume time: 258 ms

Current consumption while suspended (measured on SAMA5D2 Xplained board):
- ulp0 fast: 730uA
- ulp0     : 270uA

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
---
 arch/arm/mach-at91/pm.c         |  9 +++++----
 arch/arm/mach-at91/pm.h         |  5 +++--
 arch/arm/mach-at91/pm_suspend.S | 41 +++++++++++++++++++++++++++++++++++++----
 3 files changed, 45 insertions(+), 10 deletions(-)

diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c
index 074bde64064e..04fdcbd57100 100644
--- a/arch/arm/mach-at91/pm.c
+++ b/arch/arm/mach-at91/pm.c
@@ -51,10 +51,11 @@ static struct at91_soc_pm soc_pm = {
 };
 
 static const match_table_t pm_modes __initconst = {
-	{ AT91_PM_STANDBY, "standby" },
-	{ AT91_PM_ULP0, "ulp0" },
-	{ AT91_PM_ULP1, "ulp1" },
-	{ AT91_PM_BACKUP, "backup" },
+	{ AT91_PM_STANDBY,	"standby" },
+	{ AT91_PM_ULP0,		"ulp0" },
+	{ AT91_PM_ULP0_FAST,    "ulp0-fast" },
+	{ AT91_PM_ULP1,		"ulp1" },
+	{ AT91_PM_BACKUP,	"backup" },
 	{ -1, NULL },
 };
 
diff --git a/arch/arm/mach-at91/pm.h b/arch/arm/mach-at91/pm.h
index 218e8d1a30fb..bfb260be371e 100644
--- a/arch/arm/mach-at91/pm.h
+++ b/arch/arm/mach-at91/pm.h
@@ -19,8 +19,9 @@
 
 #define	AT91_PM_STANDBY		0x00
 #define AT91_PM_ULP0		0x01
-#define AT91_PM_ULP1		0x02
-#define	AT91_PM_BACKUP		0x03
+#define AT91_PM_ULP0_FAST	0x02
+#define AT91_PM_ULP1		0x03
+#define	AT91_PM_BACKUP		0x04
 
 #ifndef __ASSEMBLY__
 struct at91_pm_data {
diff --git a/arch/arm/mach-at91/pm_suspend.S b/arch/arm/mach-at91/pm_suspend.S
index be9764e8d3fa..0184de05c1be 100644
--- a/arch/arm/mach-at91/pm_suspend.S
+++ b/arch/arm/mach-at91/pm_suspend.S
@@ -164,7 +164,22 @@ ENDPROC(at91_backup_mode)
 
 .macro at91_pm_ulp0_mode
 	ldr	pmc, .pmc_base
+	ldr	tmp2, .pm_mode
+	ldr	tmp3, .mckr_offset
+
+	/* Check if ULP0 fast variant has been requested. */
+	cmp	tmp2, #AT91_PM_ULP0_FAST
+	bne	0f
+
+	/* Set highest prescaler for power saving */
+	ldr	tmp1, [pmc, tmp3]
+	bic	tmp1, tmp1, #AT91_PMC_PRES
+	orr	tmp1, tmp1, #AT91_PMC_PRES_64
+	str	tmp1, [pmc, tmp3]
+	wait_mckrdy
+	b	1f
 
+0:
 	/* Turn off the crystal oscillator */
 	ldr	tmp1, [pmc, #AT91_CKGR_MOR]
 	bic	tmp1, tmp1, #AT91_PMC_MOSCEN
@@ -192,7 +207,18 @@ ENDPROC(at91_backup_mode)
 	/* Wait for interrupt */
 1:	at91_cpu_idle
 
-	/* Restore RC oscillator state */
+	/* Check if ULP0 fast variant has been requested. */
+	cmp	tmp2, #AT91_PM_ULP0_FAST
+	bne	5f
+
+	/* Set lowest prescaler for fast resume. */
+	ldr	tmp1, [pmc, tmp3]
+	bic	tmp1, tmp1, #AT91_PMC_PRES
+	str	tmp1, [pmc, tmp3]
+	wait_mckrdy
+	b	6f
+
+5:	/* Restore RC oscillator state */
 	ldr	tmp1, .saved_osc_status
 	tst	tmp1, #AT91_PMC_MOSCRCS
 	beq	4f
@@ -216,6 +242,7 @@ ENDPROC(at91_backup_mode)
 	str	tmp1, [pmc, #AT91_CKGR_MOR]
 
 	wait_moscrdy
+6:
 .endm
 
 /**
@@ -473,23 +500,29 @@ ENDPROC(at91_backup_mode)
 ENTRY(at91_ulp_mode)
 	ldr	pmc, .pmc_base
 	ldr	tmp2, .mckr_offset
+	ldr	tmp3, .pm_mode
 
 	/* Save Master clock setting */
 	ldr	tmp1, [pmc, tmp2]
 	str	tmp1, .saved_mckr
 
 	/*
-	 * Set the Master clock source to slow clock
+	 * Set master clock source to:
+	 * - MAINCK if using ULP0 fast variant
+	 * - slow clock, otherwise
 	 */
 	bic	tmp1, tmp1, #AT91_PMC_CSS
+	cmp	tmp3, #AT91_PM_ULP0_FAST
+	bne	save_mck
+	orr	tmp1, tmp1, #AT91_PMC_CSS_MAIN
+save_mck:
 	str	tmp1, [pmc, tmp2]
 
 	wait_mckrdy
 
 	at91_plla_disable
 
-	ldr	r0, .pm_mode
-	cmp	r0, #AT91_PM_ULP1
+	cmp	tmp3, #AT91_PM_ULP1
 	beq	ulp1_mode
 
 	at91_pm_ulp0_mode
-- 
2.7.4

[PATCH 2/3] ARM: at91: pm: add per soc validation of pm modes

[Claudiu Beznea]

Not all SoCs supports all the PM mode. User may end up settings,
e.g. backup mode, on a non SAMA5D2 device, but the mode to not be valid.
If backup mode is used on a devices not supporting it there will be no
way of resuming other than rebooting.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
---
 arch/arm/mach-at91/at91rm9200.c | 10 +++++-
 arch/arm/mach-at91/at91sam9.c   |  9 +++++-
 arch/arm/mach-at91/generic.h    | 20 ++++++------
 arch/arm/mach-at91/pm.c         | 69 +++++++++++++++++++++++++++++++++++++----
 arch/arm/mach-at91/sam9x60.c    | 11 ++++++-
 arch/arm/mach-at91/sama5.c      | 21 +++++++++++--
 6 files changed, 119 insertions(+), 21 deletions(-)

diff --git a/arch/arm/mach-at91/at91rm9200.c b/arch/arm/mach-at91/at91rm9200.c
index 4f8186211619..7318d8e16797 100644
--- a/arch/arm/mach-at91/at91rm9200.c
+++ b/arch/arm/mach-at91/at91rm9200.c
@@ -13,12 +13,20 @@
 #include <asm/mach/arch.h>
 
 #include "generic.h"
+#include "pm.h"
+
+/* AT91RM9200 valid PM modes. */
+static const int at91rm9200_pm_modes[] = {
+	AT91_PM_STANDBY,
+	AT91_PM_ULP0,
+};
 
 static void __init at91rm9200_dt_device_init(void)
 {
 	of_platform_default_populate(NULL, NULL, NULL);
 
-	at91rm9200_pm_init();
+	at91rm9200_pm_init(at91rm9200_pm_modes,
+			   ARRAY_SIZE(at91rm9200_pm_modes));
 }
 
 static const char *const at91rm9200_dt_board_compat[] __initconst = {
diff --git a/arch/arm/mach-at91/at91sam9.c b/arch/arm/mach-at91/at91sam9.c
index 7e572189a5eb..683f2c35a116 100644
--- a/arch/arm/mach-at91/at91sam9.c
+++ b/arch/arm/mach-at91/at91sam9.c
@@ -13,12 +13,19 @@
 #include <asm/system_misc.h>
 
 #include "generic.h"
+#include "pm.h"
+
+/* AT91SAM9 valid PM modes. */
+static const int at91sam9_pm_modes[] = {
+	AT91_PM_STANDBY,
+	AT91_PM_ULP0,
+};
 
 static void __init at91sam9_init(void)
 {
 	of_platform_default_populate(NULL, NULL, NULL);
 
-	at91sam9_pm_init();
+	at91sam9_pm_init(at91sam9_pm_modes, ARRAY_SIZE(at91sam9_pm_modes));
 }
 
 static const char *const at91_dt_board_compat[] __initconst = {
diff --git a/arch/arm/mach-at91/generic.h b/arch/arm/mach-at91/generic.h
index 0a4cdcb4985b..610a12e5a71c 100644
--- a/arch/arm/mach-at91/generic.h
+++ b/arch/arm/mach-at91/generic.h
@@ -9,17 +9,17 @@
 #define _AT91_GENERIC_H
 
 #ifdef CONFIG_PM
-extern void __init at91rm9200_pm_init(void);
-extern void __init at91sam9_pm_init(void);
-extern void __init sam9x60_pm_init(void);
-extern void __init sama5_pm_init(void);
-extern void __init sama5d2_pm_init(void);
+extern void __init at91rm9200_pm_init(const int *modes, int len);
+extern void __init at91sam9_pm_init(const int *modes, int len);
+extern void __init sam9x60_pm_init(const int *modes, int len);
+extern void __init sama5_pm_init(const int *modes, int len);
+extern void __init sama5d2_pm_init(const int *modes, int len);
 #else
-static inline void __init at91rm9200_pm_init(void) { }
-static inline void __init at91sam9_pm_init(void) { }
-static inline void __init sam9x60_pm_init(void) { }
-static inline void __init sama5_pm_init(void) { }
-static inline void __init sama5d2_pm_init(void) { }
+static inline void __init at91rm9200_pm_init(const int *modes, int len) { }
+static inline void __init at91sam9_pm_init(const int *modes, int len) { }
+static inline void __init sam9x60_pm_init(const int *modes, int len) { }
+static inline void __init sama5_pm_init(const int *modes, int len) { }
+static inline void __init sama5d2_pm_init(const int *modes, int len) { }
 #endif
 
 #endif /* _AT91_GENERIC_H */
diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c
index 04fdcbd57100..caf87efc7eeb 100644
--- a/arch/arm/mach-at91/pm.c
+++ b/arch/arm/mach-at91/pm.c
@@ -785,6 +785,59 @@ static const struct of_device_id atmel_pmc_ids[] __initconst = {
 	{ /* sentinel */ },
 };
 
+static void __init at91_pm_modes_validate(const int *modes, int len)
+{
+	u8 i, located = 0;
+	int mode;
+
+#define STANDBY	BIT(0)
+#define SUSPEND	BIT(1)
+
+	for (i = 0; i < len; i++) {
+		if ((located & STANDBY) && (located & SUSPEND))
+			break;
+
+		if (modes[i] == soc_pm.data.standby_mode &&
+		    !(located & STANDBY)) {
+			located |= STANDBY;
+			continue;
+		}
+
+		if (modes[i] == soc_pm.data.suspend_mode &&
+		    !(located & SUSPEND)) {
+			located |= SUSPEND;
+			continue;
+		}
+	}
+
+	if (!(located & STANDBY)) {
+		if (soc_pm.data.suspend_mode == AT91_PM_STANDBY)
+			mode = AT91_PM_ULP0;
+		else
+			mode = AT91_PM_STANDBY;
+
+		pr_warn("AT91: PM: %s mode not supported! Using %s.\n",
+			pm_modes[soc_pm.data.standby_mode].pattern,
+			pm_modes[mode].pattern);
+		soc_pm.data.standby_mode = mode;
+	}
+
+	if (!(located & SUSPEND)) {
+		if (soc_pm.data.standby_mode == AT91_PM_ULP0)
+			mode = AT91_PM_STANDBY;
+		else
+			mode = AT91_PM_ULP0;
+
+		pr_warn("AT91: PM: %s mode not supported! Using %s.\n",
+			pm_modes[soc_pm.data.suspend_mode].pattern,
+			pm_modes[mode].pattern);
+		soc_pm.data.suspend_mode = mode;
+	}
+
+#undef STANDBY
+#undef SUSPEND
+}
+
 static void __init at91_pm_init(void (*pm_idle)(void))
 {
 	struct device_node *pmc_np;
@@ -821,11 +874,12 @@ static void __init at91_pm_init(void (*pm_idle)(void))
 	}
 }
 
-void __init at91rm9200_pm_init(void)
+void __init at91rm9200_pm_init(const int *modes, int len)
 {
 	if (!IS_ENABLED(CONFIG_SOC_AT91RM9200))
 		return;
 
+	at91_pm_modes_validate(modes, len);
 	at91_dt_ramc();
 
 	/*
@@ -836,11 +890,12 @@ void __init at91rm9200_pm_init(void)
 	at91_pm_init(at91rm9200_idle);
 }
 
-void __init sam9x60_pm_init(void)
+void __init sam9x60_pm_init(const int *modes, int len)
 {
 	if (!IS_ENABLED(CONFIG_SOC_SAM9X60))
 		return;
 
+	at91_pm_modes_validate(modes, len);
 	at91_pm_modes_init();
 	at91_dt_ramc();
 	at91_pm_init(at91sam9x60_idle);
@@ -849,31 +904,33 @@ void __init sam9x60_pm_init(void)
 	soc_pm.config_pmc_ws = at91_sam9x60_config_pmc_ws;
 }
 
-void __init at91sam9_pm_init(void)
+void __init at91sam9_pm_init(const int *modes, int len)
 {
 	if (!IS_ENABLED(CONFIG_SOC_AT91SAM9))
 		return;
 
+	at91_pm_modes_validate(modes, len);
 	at91_dt_ramc();
 	at91_pm_init(at91sam9_idle);
 }
 
-void __init sama5_pm_init(void)
+void __init sama5_pm_init(const int *modes, int len)
 {
 	if (!IS_ENABLED(CONFIG_SOC_SAMA5))
 		return;
 
+	at91_pm_modes_validate(modes, len);
 	at91_dt_ramc();
 	at91_pm_init(NULL);
 }
 
-void __init sama5d2_pm_init(void)
+void __init sama5d2_pm_init(const int *modes, int len)
 {
 	if (!IS_ENABLED(CONFIG_SOC_SAMA5D2))
 		return;
 
+	sama5_pm_init(modes, len);
 	at91_pm_modes_init();
-	sama5_pm_init();
 
 	soc_pm.ws_ids = sama5d2_ws_ids;
 	soc_pm.config_shdwc_ws = at91_sama5d2_config_shdwc_ws;
diff --git a/arch/arm/mach-at91/sam9x60.c b/arch/arm/mach-at91/sam9x60.c
index d8c739d25458..d7c869c7b542 100644
--- a/arch/arm/mach-at91/sam9x60.c
+++ b/arch/arm/mach-at91/sam9x60.c
@@ -14,12 +14,21 @@
 #include <asm/system_misc.h>
 
 #include "generic.h"
+#include "pm.h"
+
+/* SAM9X60 valid PM modes. */
+static const int sam9x60_pm_modes[] = {
+	AT91_PM_STANDBY,
+	AT91_PM_ULP0,
+	AT91_PM_ULP0_FAST,
+	AT91_PM_ULP1,
+};
 
 static void __init sam9x60_init(void)
 {
 	of_platform_default_populate(NULL, NULL, NULL);
 
-	sam9x60_pm_init();
+	sam9x60_pm_init(sam9x60_pm_modes, ARRAY_SIZE(sam9x60_pm_modes));
 }
 
 static const char *const sam9x60_dt_board_compat[] __initconst = {
diff --git a/arch/arm/mach-at91/sama5.c b/arch/arm/mach-at91/sama5.c
index 89dab7cf01e8..7eb124612a10 100644
--- a/arch/arm/mach-at91/sama5.c
+++ b/arch/arm/mach-at91/sama5.c
@@ -14,11 +14,19 @@
 #include <asm/system_misc.h>
 
 #include "generic.h"
+#include "pm.h"
+
+/* SAMA5 valid PM modes. */
+static const int sama5_pm_modes[] = {
+	AT91_PM_STANDBY,
+	AT91_PM_ULP0,
+	AT91_PM_ULP0_FAST,
+};
 
 static void __init sama5_dt_device_init(void)
 {
 	of_platform_default_populate(NULL, NULL, NULL);
-	sama5_pm_init();
+	sama5_pm_init(sama5_pm_modes, ARRAY_SIZE(sama5_pm_modes));
 }
 
 static const char *const sama5_dt_board_compat[] __initconst = {
@@ -44,10 +52,19 @@ DT_MACHINE_START(sama5_alt_dt, "Atmel SAMA5")
 	.l2c_aux_mask	= ~0UL,
 MACHINE_END
 
+/* sama5d2 PM modes. */
+static const int sama5d2_pm_modes[] = {
+	AT91_PM_STANDBY,
+	AT91_PM_ULP0,
+	AT91_PM_ULP0_FAST,
+	AT91_PM_ULP1,
+	AT91_PM_BACKUP,
+};
+
 static void __init sama5d2_init(void)
 {
 	of_platform_default_populate(NULL, NULL, NULL);
-	sama5d2_pm_init();
+	sama5d2_pm_init(sama5d2_pm_modes, ARRAY_SIZE(sama5d2_pm_modes));
 }
 
 static const char *const sama5d2_compat[] __initconst = {
-- 
2.7.4

[PATCH 3/3] ARM: at91: pm: put node after its usage

[Claudiu Beznea]

of_find_matching_node_and_match() returns a node pointer with refcount
incremented. Use of_node_put() after the node has been used.

Fixes: 13f16017d3e3f ("ARM: at91: pm: Tie the USB clock mask to the pmc")
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
---
 arch/arm/mach-at91/pm.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c
index caf87efc7eeb..3d2ee8273b4c 100644
--- a/arch/arm/mach-at91/pm.c
+++ b/arch/arm/mach-at91/pm.c
@@ -849,6 +849,7 @@ static void __init at91_pm_init(void (*pm_idle)(void))
 
 	pmc_np = of_find_matching_node_and_match(NULL, atmel_pmc_ids, &of_id);
 	soc_pm.data.pmc = of_iomap(pmc_np, 0);
+	of_node_put(pmc_np);
 	if (!soc_pm.data.pmc) {
 		pr_err("AT91: PM not supported, PMC not found\n");
 		return;
-- 
2.7.4

Re: [PATCH 2/3] ARM: at91: pm: add per soc validation of pm modes

[Alexandre Belloni]

On 03/08/2020 10:25:16+0300, Claudiu Beznea wrote:
> Not all SoCs supports all the PM mode. User may end up settings,
> e.g. backup mode, on a non SAMA5D2 device, but the mode to not be valid.
> If backup mode is used on a devices not supporting it there will be no
> way of resuming other than rebooting.

I don't think this actually happens as if backup mode is requested on a
non sama5d2 device, of_find_compatible_node(NULL, NULL,
"atmel,sama5d2-sfrbu") will fail and the PM will default to
AT91_PM_ULP0.

ULP1 will also default to ULP0 if the shdwc is not from sama5d2 or
sam9x60.

I'm guessing the actual issue is introduced with ulp0 fast.

> 
> Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
> ---
>  arch/arm/mach-at91/at91rm9200.c | 10 +++++-
>  arch/arm/mach-at91/at91sam9.c   |  9 +++++-
>  arch/arm/mach-at91/generic.h    | 20 ++++++------
>  arch/arm/mach-at91/pm.c         | 69 +++++++++++++++++++++++++++++++++++++----
>  arch/arm/mach-at91/sam9x60.c    | 11 ++++++-
>  arch/arm/mach-at91/sama5.c      | 21 +++++++++++--
>  6 files changed, 119 insertions(+), 21 deletions(-)
> 
> diff --git a/arch/arm/mach-at91/at91rm9200.c b/arch/arm/mach-at91/at91rm9200.c
> index 4f8186211619..7318d8e16797 100644
> --- a/arch/arm/mach-at91/at91rm9200.c
> +++ b/arch/arm/mach-at91/at91rm9200.c
> @@ -13,12 +13,20 @@
>  #include <asm/mach/arch.h>
>  
>  #include "generic.h"
> +#include "pm.h"
> +
> +/* AT91RM9200 valid PM modes. */
> +static const int at91rm9200_pm_modes[] = {
> +	AT91_PM_STANDBY,
> +	AT91_PM_ULP0,
> +};
>  
>  static void __init at91rm9200_dt_device_init(void)
>  {
>  	of_platform_default_populate(NULL, NULL, NULL);
>  
> -	at91rm9200_pm_init();
> +	at91rm9200_pm_init(at91rm9200_pm_modes,
> +			   ARRAY_SIZE(at91rm9200_pm_modes));
>  }
>  

You can avoid the changes in the soc files and leave everything
contained in pm.c as each <soc>_pm_init has a known list of mode that
will very likely never change. Bonus points if you make the arrays
__initdata.

>  static const char *const at91rm9200_dt_board_compat[] __initconst = {
> diff --git a/arch/arm/mach-at91/at91sam9.c b/arch/arm/mach-at91/at91sam9.c
> index 7e572189a5eb..683f2c35a116 100644
> --- a/arch/arm/mach-at91/at91sam9.c
> +++ b/arch/arm/mach-at91/at91sam9.c
> @@ -13,12 +13,19 @@
>  #include <asm/system_misc.h>
>  
>  #include "generic.h"
> +#include "pm.h"
> +
> +/* AT91SAM9 valid PM modes. */
> +static const int at91sam9_pm_modes[] = {
> +	AT91_PM_STANDBY,
> +	AT91_PM_ULP0,
> +};
>  
>  static void __init at91sam9_init(void)
>  {
>  	of_platform_default_populate(NULL, NULL, NULL);
>  
> -	at91sam9_pm_init();
> +	at91sam9_pm_init(at91sam9_pm_modes, ARRAY_SIZE(at91sam9_pm_modes));
>  }
>  
>  static const char *const at91_dt_board_compat[] __initconst = {
> diff --git a/arch/arm/mach-at91/generic.h b/arch/arm/mach-at91/generic.h
> index 0a4cdcb4985b..610a12e5a71c 100644
> --- a/arch/arm/mach-at91/generic.h
> +++ b/arch/arm/mach-at91/generic.h
> @@ -9,17 +9,17 @@
>  #define _AT91_GENERIC_H
>  
>  #ifdef CONFIG_PM
> -extern void __init at91rm9200_pm_init(void);
> -extern void __init at91sam9_pm_init(void);
> -extern void __init sam9x60_pm_init(void);
> -extern void __init sama5_pm_init(void);
> -extern void __init sama5d2_pm_init(void);
> +extern void __init at91rm9200_pm_init(const int *modes, int len);
> +extern void __init at91sam9_pm_init(const int *modes, int len);
> +extern void __init sam9x60_pm_init(const int *modes, int len);
> +extern void __init sama5_pm_init(const int *modes, int len);
> +extern void __init sama5d2_pm_init(const int *modes, int len);
>  #else
> -static inline void __init at91rm9200_pm_init(void) { }
> -static inline void __init at91sam9_pm_init(void) { }
> -static inline void __init sam9x60_pm_init(void) { }
> -static inline void __init sama5_pm_init(void) { }
> -static inline void __init sama5d2_pm_init(void) { }
> +static inline void __init at91rm9200_pm_init(const int *modes, int len) { }
> +static inline void __init at91sam9_pm_init(const int *modes, int len) { }
> +static inline void __init sam9x60_pm_init(const int *modes, int len) { }
> +static inline void __init sama5_pm_init(const int *modes, int len) { }
> +static inline void __init sama5d2_pm_init(const int *modes, int len) { }
>  #endif
>  

Then this change is not necessary.

>  #endif /* _AT91_GENERIC_H */
> diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c
> index 04fdcbd57100..caf87efc7eeb 100644
> --- a/arch/arm/mach-at91/pm.c
> +++ b/arch/arm/mach-at91/pm.c
> @@ -785,6 +785,59 @@ static const struct of_device_id atmel_pmc_ids[] __initconst = {
>  	{ /* sentinel */ },
>  };
>  
> +static void __init at91_pm_modes_validate(const int *modes, int len)
> +{
> +	u8 i, located = 0;
> +	int mode;
> +
> +#define STANDBY	BIT(0)
> +#define SUSPEND	BIT(1)
> +
> +	for (i = 0; i < len; i++) {
> +		if ((located & STANDBY) && (located & SUSPEND))
> +			break;
> +
> +		if (modes[i] == soc_pm.data.standby_mode &&
> +		    !(located & STANDBY)) {
> +			located |= STANDBY;
> +			continue;
> +		}
> +
> +		if (modes[i] == soc_pm.data.suspend_mode &&
> +		    !(located & SUSPEND)) {
> +			located |= SUSPEND;
> +			continue;
> +		}
> +	}
> +
> +	if (!(located & STANDBY)) {
> +		if (soc_pm.data.suspend_mode == AT91_PM_STANDBY)
> +			mode = AT91_PM_ULP0;
> +		else
> +			mode = AT91_PM_STANDBY;
> +
> +		pr_warn("AT91: PM: %s mode not supported! Using %s.\n",
> +			pm_modes[soc_pm.data.standby_mode].pattern,
> +			pm_modes[mode].pattern);
> +		soc_pm.data.standby_mode = mode;
> +	}
> +
> +	if (!(located & SUSPEND)) {
> +		if (soc_pm.data.standby_mode == AT91_PM_ULP0)
> +			mode = AT91_PM_STANDBY;
> +		else
> +			mode = AT91_PM_ULP0;
> +
> +		pr_warn("AT91: PM: %s mode not supported! Using %s.\n",
> +			pm_modes[soc_pm.data.suspend_mode].pattern,
> +			pm_modes[mode].pattern);
> +		soc_pm.data.suspend_mode = mode;
> +	}
> +
> +#undef STANDBY
> +#undef SUSPEND

You should use two booleans instead of a bit array, this would not make
the code longer and will avoid this #def/#undef thing.

> +}
> +
>  static void __init at91_pm_init(void (*pm_idle)(void))
>  {
>  	struct device_node *pmc_np;
> @@ -821,11 +874,12 @@ static void __init at91_pm_init(void (*pm_idle)(void))
>  	}
>  }
>  
> -void __init at91rm9200_pm_init(void)
> +void __init at91rm9200_pm_init(const int *modes, int len)
>  {
>  	if (!IS_ENABLED(CONFIG_SOC_AT91RM9200))
>  		return;
>  
> +	at91_pm_modes_validate(modes, len);
>  	at91_dt_ramc();
>  
>  	/*
> @@ -836,11 +890,12 @@ void __init at91rm9200_pm_init(void)
>  	at91_pm_init(at91rm9200_idle);
>  }
>  
> -void __init sam9x60_pm_init(void)
> +void __init sam9x60_pm_init(const int *modes, int len)
>  {
>  	if (!IS_ENABLED(CONFIG_SOC_SAM9X60))
>  		return;
>  
> +	at91_pm_modes_validate(modes, len);
>  	at91_pm_modes_init();
>  	at91_dt_ramc();
>  	at91_pm_init(at91sam9x60_idle);
> @@ -849,31 +904,33 @@ void __init sam9x60_pm_init(void)
>  	soc_pm.config_pmc_ws = at91_sam9x60_config_pmc_ws;
>  }
>  
> -void __init at91sam9_pm_init(void)
> +void __init at91sam9_pm_init(const int *modes, int len)
>  {
>  	if (!IS_ENABLED(CONFIG_SOC_AT91SAM9))
>  		return;
>  
> +	at91_pm_modes_validate(modes, len);
>  	at91_dt_ramc();
>  	at91_pm_init(at91sam9_idle);
>  }
>  
> -void __init sama5_pm_init(void)
> +void __init sama5_pm_init(const int *modes, int len)
>  {
>  	if (!IS_ENABLED(CONFIG_SOC_SAMA5))
>  		return;
>  
> +	at91_pm_modes_validate(modes, len);
>  	at91_dt_ramc();
>  	at91_pm_init(NULL);
>  }
>  
> -void __init sama5d2_pm_init(void)
> +void __init sama5d2_pm_init(const int *modes, int len)
>  {
>  	if (!IS_ENABLED(CONFIG_SOC_SAMA5D2))
>  		return;
>  
> +	sama5_pm_init(modes, len);
>  	at91_pm_modes_init();
> -	sama5_pm_init();
>  
>  	soc_pm.ws_ids = sama5d2_ws_ids;
>  	soc_pm.config_shdwc_ws = at91_sama5d2_config_shdwc_ws;
> diff --git a/arch/arm/mach-at91/sam9x60.c b/arch/arm/mach-at91/sam9x60.c
> index d8c739d25458..d7c869c7b542 100644
> --- a/arch/arm/mach-at91/sam9x60.c
> +++ b/arch/arm/mach-at91/sam9x60.c
> @@ -14,12 +14,21 @@
>  #include <asm/system_misc.h>
>  
>  #include "generic.h"
> +#include "pm.h"
> +
> +/* SAM9X60 valid PM modes. */
> +static const int sam9x60_pm_modes[] = {
> +	AT91_PM_STANDBY,
> +	AT91_PM_ULP0,
> +	AT91_PM_ULP0_FAST,
> +	AT91_PM_ULP1,
> +};
>  
>  static void __init sam9x60_init(void)
>  {
>  	of_platform_default_populate(NULL, NULL, NULL);
>  
> -	sam9x60_pm_init();
> +	sam9x60_pm_init(sam9x60_pm_modes, ARRAY_SIZE(sam9x60_pm_modes));
>  }
>  
>  static const char *const sam9x60_dt_board_compat[] __initconst = {
> diff --git a/arch/arm/mach-at91/sama5.c b/arch/arm/mach-at91/sama5.c
> index 89dab7cf01e8..7eb124612a10 100644
> --- a/arch/arm/mach-at91/sama5.c
> +++ b/arch/arm/mach-at91/sama5.c
> @@ -14,11 +14,19 @@
>  #include <asm/system_misc.h>
>  
>  #include "generic.h"
> +#include "pm.h"
> +
> +/* SAMA5 valid PM modes. */
> +static const int sama5_pm_modes[] = {
> +	AT91_PM_STANDBY,
> +	AT91_PM_ULP0,
> +	AT91_PM_ULP0_FAST,
> +};
>  
>  static void __init sama5_dt_device_init(void)
>  {
>  	of_platform_default_populate(NULL, NULL, NULL);
> -	sama5_pm_init();
> +	sama5_pm_init(sama5_pm_modes, ARRAY_SIZE(sama5_pm_modes));
>  }
>  
>  static const char *const sama5_dt_board_compat[] __initconst = {
> @@ -44,10 +52,19 @@ DT_MACHINE_START(sama5_alt_dt, "Atmel SAMA5")
>  	.l2c_aux_mask	= ~0UL,
>  MACHINE_END
>  
> +/* sama5d2 PM modes. */
> +static const int sama5d2_pm_modes[] = {
> +	AT91_PM_STANDBY,
> +	AT91_PM_ULP0,
> +	AT91_PM_ULP0_FAST,
> +	AT91_PM_ULP1,
> +	AT91_PM_BACKUP,
> +};
> +
>  static void __init sama5d2_init(void)
>  {
>  	of_platform_default_populate(NULL, NULL, NULL);
> -	sama5d2_pm_init();
> +	sama5d2_pm_init(sama5d2_pm_modes, ARRAY_SIZE(sama5d2_pm_modes));
>  }
>  
>  static const char *const sama5d2_compat[] __initconst = {
> -- 
> 2.7.4
> 

-- 
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

Re: [PATCH 2/3] ARM: at91: pm: add per soc validation of pm modes

[Claudiu.Beznea]

On 03.08.2020 11:34, Alexandre Belloni wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> 
> On 03/08/2020 10:25:16+0300, Claudiu Beznea wrote:
>> Not all SoCs supports all the PM mode. User may end up settings,
>> e.g. backup mode, on a non SAMA5D2 device, but the mode to not be valid.
>> If backup mode is used on a devices not supporting it there will be no
>> way of resuming other than rebooting.
> 
> I don't think this actually happens as if backup mode is requested on a
> non sama5d2 device, of_find_compatible_node(NULL, NULL,
> "atmel,sama5d2-sfrbu") will fail and the PM will default to
> AT91_PM_ULP0.

of_find_compatible_node(NULL, NULL, "atmel,sama5d2-sfrbu") is called by
at91_pm_backup_init() which is called by at91_pm_modes_init() which is
called only by sam9x60_pm_init() and sama5d2_pm_init(). Same thing with
shutdown controller compatibles. Concluding, backup could be requested for
SoCs calling:
- at91rm9200_pm_init()
- at91sam9_pm_init()
- sama5_pm_init()

The other solution for this would be to call at91_pm_modes_init() also in
the functions above. I choose the approach in this patch to avoid tracking
the dependency b/w compatibles and supported modes.

Let me know what would you prefer as a solution.

> 
> ULP1 will also default to ULP0 if the shdwc is not from sama5d2 or
> sam9x60.>
> I'm guessing the actual issue is introduced with ulp0 fast.
> 
>>
>> Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
>> ---
>>  arch/arm/mach-at91/at91rm9200.c | 10 +++++-
>>  arch/arm/mach-at91/at91sam9.c   |  9 +++++-
>>  arch/arm/mach-at91/generic.h    | 20 ++++++------
>>  arch/arm/mach-at91/pm.c         | 69 +++++++++++++++++++++++++++++++++++++----
>>  arch/arm/mach-at91/sam9x60.c    | 11 ++++++-
>>  arch/arm/mach-at91/sama5.c      | 21 +++++++++++--
>>  6 files changed, 119 insertions(+), 21 deletions(-)
>>
>> diff --git a/arch/arm/mach-at91/at91rm9200.c b/arch/arm/mach-at91/at91rm9200.c
>> index 4f8186211619..7318d8e16797 100644
>> --- a/arch/arm/mach-at91/at91rm9200.c
>> +++ b/arch/arm/mach-at91/at91rm9200.c
>> @@ -13,12 +13,20 @@
>>  #include <asm/mach/arch.h>
>>
>>  #include "generic.h"
>> +#include "pm.h"
>> +
>> +/* AT91RM9200 valid PM modes. */
>> +static const int at91rm9200_pm_modes[] = {
>> +     AT91_PM_STANDBY,
>> +     AT91_PM_ULP0,
>> +};
>>
>>  static void __init at91rm9200_dt_device_init(void)
>>  {
>>       of_platform_default_populate(NULL, NULL, NULL);
>>
>> -     at91rm9200_pm_init();
>> +     at91rm9200_pm_init(at91rm9200_pm_modes,
>> +                        ARRAY_SIZE(at91rm9200_pm_modes));
>>  }
>>
> 
> You can avoid the changes in the soc files and leave everything
> contained in pm.c as each <soc>_pm_init has a known list of mode that
> will very likely never change. Bonus points if you make the arrays
> __initdata.

That was my initial approach. I went with the one in this patch to avoid
adding yet another struct of_device_id array in pm.c and keep code in pm.c
somehow platform independent. If you feel is better your way, then OK, I
have no problems with moving it in pm.c.

> 
>>  static const char *const at91rm9200_dt_board_compat[] __initconst = {
>> diff --git a/arch/arm/mach-at91/at91sam9.c b/arch/arm/mach-at91/at91sam9.c
>> index 7e572189a5eb..683f2c35a116 100644
>> --- a/arch/arm/mach-at91/at91sam9.c
>> +++ b/arch/arm/mach-at91/at91sam9.c
>> @@ -13,12 +13,19 @@
>>  #include <asm/system_misc.h>
>>
>>  #include "generic.h"
>> +#include "pm.h"
>> +
>> +/* AT91SAM9 valid PM modes. */
>> +static const int at91sam9_pm_modes[] = {
>> +     AT91_PM_STANDBY,
>> +     AT91_PM_ULP0,
>> +};
>>
>>  static void __init at91sam9_init(void)
>>  {
>>       of_platform_default_populate(NULL, NULL, NULL);
>>
>> -     at91sam9_pm_init();
>> +     at91sam9_pm_init(at91sam9_pm_modes, ARRAY_SIZE(at91sam9_pm_modes));
>>  }
>>
>>  static const char *const at91_dt_board_compat[] __initconst = {
>> diff --git a/arch/arm/mach-at91/generic.h b/arch/arm/mach-at91/generic.h
>> index 0a4cdcb4985b..610a12e5a71c 100644
>> --- a/arch/arm/mach-at91/generic.h
>> +++ b/arch/arm/mach-at91/generic.h
>> @@ -9,17 +9,17 @@
>>  #define _AT91_GENERIC_H
>>
>>  #ifdef CONFIG_PM
>> -extern void __init at91rm9200_pm_init(void);
>> -extern void __init at91sam9_pm_init(void);
>> -extern void __init sam9x60_pm_init(void);
>> -extern void __init sama5_pm_init(void);
>> -extern void __init sama5d2_pm_init(void);
>> +extern void __init at91rm9200_pm_init(const int *modes, int len);
>> +extern void __init at91sam9_pm_init(const int *modes, int len);
>> +extern void __init sam9x60_pm_init(const int *modes, int len);
>> +extern void __init sama5_pm_init(const int *modes, int len);
>> +extern void __init sama5d2_pm_init(const int *modes, int len);
>>  #else
>> -static inline void __init at91rm9200_pm_init(void) { }
>> -static inline void __init at91sam9_pm_init(void) { }
>> -static inline void __init sam9x60_pm_init(void) { }
>> -static inline void __init sama5_pm_init(void) { }
>> -static inline void __init sama5d2_pm_init(void) { }
>> +static inline void __init at91rm9200_pm_init(const int *modes, int len) { }
>> +static inline void __init at91sam9_pm_init(const int *modes, int len) { }
>> +static inline void __init sam9x60_pm_init(const int *modes, int len) { }
>> +static inline void __init sama5_pm_init(const int *modes, int len) { }
>> +static inline void __init sama5d2_pm_init(const int *modes, int len) { }
>>  #endif
>>
> 
> Then this change is not necessary.
> 
>>  #endif /* _AT91_GENERIC_H */
>> diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c
>> index 04fdcbd57100..caf87efc7eeb 100644
>> --- a/arch/arm/mach-at91/pm.c
>> +++ b/arch/arm/mach-at91/pm.c
>> @@ -785,6 +785,59 @@ static const struct of_device_id atmel_pmc_ids[] __initconst = {
>>       { /* sentinel */ },
>>  };
>>
>> +static void __init at91_pm_modes_validate(const int *modes, int len)
>> +{
>> +     u8 i, located = 0;
>> +     int mode;
>> +
>> +#define STANDBY      BIT(0)
>> +#define SUSPEND      BIT(1)
>> +
>> +     for (i = 0; i < len; i++) {
>> +             if ((located & STANDBY) && (located & SUSPEND))
>> +                     break;
>> +
>> +             if (modes[i] == soc_pm.data.standby_mode &&
>> +                 !(located & STANDBY)) {
>> +                     located |= STANDBY;
>> +                     continue;
>> +             }
>> +
>> +             if (modes[i] == soc_pm.data.suspend_mode &&
>> +                 !(located & SUSPEND)) {
>> +                     located |= SUSPEND;
>> +                     continue;
>> +             }
>> +     }
>> +
>> +     if (!(located & STANDBY)) {
>> +             if (soc_pm.data.suspend_mode == AT91_PM_STANDBY)
>> +                     mode = AT91_PM_ULP0;
>> +             else
>> +                     mode = AT91_PM_STANDBY;
>> +
>> +             pr_warn("AT91: PM: %s mode not supported! Using %s.\n",
>> +                     pm_modes[soc_pm.data.standby_mode].pattern,
>> +                     pm_modes[mode].pattern);
>> +             soc_pm.data.standby_mode = mode;
>> +     }
>> +
>> +     if (!(located & SUSPEND)) {
>> +             if (soc_pm.data.standby_mode == AT91_PM_ULP0)
>> +                     mode = AT91_PM_STANDBY;
>> +             else
>> +                     mode = AT91_PM_ULP0;
>> +
>> +             pr_warn("AT91: PM: %s mode not supported! Using %s.\n",
>> +                     pm_modes[soc_pm.data.suspend_mode].pattern,
>> +                     pm_modes[mode].pattern);
>> +             soc_pm.data.suspend_mode = mode;
>> +     }
>> +
>> +#undef STANDBY
>> +#undef SUSPEND
> 
> You should use two booleans instead of a bit array, this would not make
> the code longer and will avoid this #def/#undef thing.

OK, I have no strong opinion on this. I'll switch to booleans.

> 
>> +}
>> +
>>  static void __init at91_pm_init(void (*pm_idle)(void))
>>  {
>>       struct device_node *pmc_np;
>> @@ -821,11 +874,12 @@ static void __init at91_pm_init(void (*pm_idle)(void))
>>       }
>>  }
>>
>> -void __init at91rm9200_pm_init(void)
>> +void __init at91rm9200_pm_init(const int *modes, int len)
>>  {
>>       if (!IS_ENABLED(CONFIG_SOC_AT91RM9200))
>>               return;
>>
>> +     at91_pm_modes_validate(modes, len);
>>       at91_dt_ramc();
>>
>>       /*
>> @@ -836,11 +890,12 @@ void __init at91rm9200_pm_init(void)
>>       at91_pm_init(at91rm9200_idle);
>>  }
>>
>> -void __init sam9x60_pm_init(void)
>> +void __init sam9x60_pm_init(const int *modes, int len)
>>  {
>>       if (!IS_ENABLED(CONFIG_SOC_SAM9X60))
>>               return;
>>
>> +     at91_pm_modes_validate(modes, len);
>>       at91_pm_modes_init();
>>       at91_dt_ramc();
>>       at91_pm_init(at91sam9x60_idle);
>> @@ -849,31 +904,33 @@ void __init sam9x60_pm_init(void)
>>       soc_pm.config_pmc_ws = at91_sam9x60_config_pmc_ws;
>>  }
>>
>> -void __init at91sam9_pm_init(void)
>> +void __init at91sam9_pm_init(const int *modes, int len)
>>  {
>>       if (!IS_ENABLED(CONFIG_SOC_AT91SAM9))
>>               return;
>>
>> +     at91_pm_modes_validate(modes, len);
>>       at91_dt_ramc();
>>       at91_pm_init(at91sam9_idle);
>>  }
>>
>> -void __init sama5_pm_init(void)
>> +void __init sama5_pm_init(const int *modes, int len)
>>  {
>>       if (!IS_ENABLED(CONFIG_SOC_SAMA5))
>>               return;
>>
>> +     at91_pm_modes_validate(modes, len);
>>       at91_dt_ramc();
>>       at91_pm_init(NULL);
>>  }
>>
>> -void __init sama5d2_pm_init(void)
>> +void __init sama5d2_pm_init(const int *modes, int len)
>>  {
>>       if (!IS_ENABLED(CONFIG_SOC_SAMA5D2))
>>               return;
>>
>> +     sama5_pm_init(modes, len);
>>       at91_pm_modes_init();
>> -     sama5_pm_init();
>>
>>       soc_pm.ws_ids = sama5d2_ws_ids;
>>       soc_pm.config_shdwc_ws = at91_sama5d2_config_shdwc_ws;
>> diff --git a/arch/arm/mach-at91/sam9x60.c b/arch/arm/mach-at91/sam9x60.c
>> index d8c739d25458..d7c869c7b542 100644
>> --- a/arch/arm/mach-at91/sam9x60.c
>> +++ b/arch/arm/mach-at91/sam9x60.c
>> @@ -14,12 +14,21 @@
>>  #include <asm/system_misc.h>
>>
>>  #include "generic.h"
>> +#include "pm.h"
>> +
>> +/* SAM9X60 valid PM modes. */
>> +static const int sam9x60_pm_modes[] = {
>> +     AT91_PM_STANDBY,
>> +     AT91_PM_ULP0,
>> +     AT91_PM_ULP0_FAST,
>> +     AT91_PM_ULP1,
>> +};
>>
>>  static void __init sam9x60_init(void)
>>  {
>>       of_platform_default_populate(NULL, NULL, NULL);
>>
>> -     sam9x60_pm_init();
>> +     sam9x60_pm_init(sam9x60_pm_modes, ARRAY_SIZE(sam9x60_pm_modes));
>>  }
>>
>>  static const char *const sam9x60_dt_board_compat[] __initconst = {
>> diff --git a/arch/arm/mach-at91/sama5.c b/arch/arm/mach-at91/sama5.c
>> index 89dab7cf01e8..7eb124612a10 100644
>> --- a/arch/arm/mach-at91/sama5.c
>> +++ b/arch/arm/mach-at91/sama5.c
>> @@ -14,11 +14,19 @@
>>  #include <asm/system_misc.h>
>>
>>  #include "generic.h"
>> +#include "pm.h"
>> +
>> +/* SAMA5 valid PM modes. */
>> +static const int sama5_pm_modes[] = {
>> +     AT91_PM_STANDBY,
>> +     AT91_PM_ULP0,
>> +     AT91_PM_ULP0_FAST,
>> +};
>>
>>  static void __init sama5_dt_device_init(void)
>>  {
>>       of_platform_default_populate(NULL, NULL, NULL);
>> -     sama5_pm_init();
>> +     sama5_pm_init(sama5_pm_modes, ARRAY_SIZE(sama5_pm_modes));
>>  }
>>
>>  static const char *const sama5_dt_board_compat[] __initconst = {
>> @@ -44,10 +52,19 @@ DT_MACHINE_START(sama5_alt_dt, "Atmel SAMA5")
>>       .l2c_aux_mask   = ~0UL,
>>  MACHINE_END
>>
>> +/* sama5d2 PM modes. */
>> +static const int sama5d2_pm_modes[] = {
>> +     AT91_PM_STANDBY,
>> +     AT91_PM_ULP0,
>> +     AT91_PM_ULP0_FAST,
>> +     AT91_PM_ULP1,
>> +     AT91_PM_BACKUP,
>> +};
>> +
>>  static void __init sama5d2_init(void)
>>  {
>>       of_platform_default_populate(NULL, NULL, NULL);
>> -     sama5d2_pm_init();
>> +     sama5d2_pm_init(sama5d2_pm_modes, ARRAY_SIZE(sama5d2_pm_modes));
>>  }
>>
>>  static const char *const sama5d2_compat[] __initconst = {
>> --
>> 2.7.4
>>
> 
> --
> Alexandre Belloni, Bootlin
> Embedded Linux and Kernel engineering
> https://bootlin.com
> 

Re: [PATCH 2/3] ARM: at91: pm: add per soc validation of pm modes

[Alexandre Belloni]

On 03/08/2020 10:54:51+0000, Claudiu.Beznea@microchip.com wrote:
> >> diff --git a/arch/arm/mach-at91/at91rm9200.c b/arch/arm/mach-at91/at91rm9200.c
> >> index 4f8186211619..7318d8e16797 100644
> >> --- a/arch/arm/mach-at91/at91rm9200.c
> >> +++ b/arch/arm/mach-at91/at91rm9200.c
> >> @@ -13,12 +13,20 @@
> >>  #include <asm/mach/arch.h>
> >>
> >>  #include "generic.h"
> >> +#include "pm.h"
> >> +
> >> +/* AT91RM9200 valid PM modes. */
> >> +static const int at91rm9200_pm_modes[] = {
> >> +     AT91_PM_STANDBY,
> >> +     AT91_PM_ULP0,
> >> +};
> >>
> >>  static void __init at91rm9200_dt_device_init(void)
> >>  {
> >>       of_platform_default_populate(NULL, NULL, NULL);
> >>
> >> -     at91rm9200_pm_init();
> >> +     at91rm9200_pm_init(at91rm9200_pm_modes,
> >> +                        ARRAY_SIZE(at91rm9200_pm_modes));
> >>  }
> >>
> > 
> > You can avoid the changes in the soc files and leave everything
> > contained in pm.c as each <soc>_pm_init has a known list of mode that
> > will very likely never change. Bonus points if you make the arrays
> > __initdata.
> 
> That was my initial approach. I went with the one in this patch to avoid
> adding yet another struct of_device_id array in pm.c and keep code in pm.c
> somehow platform independent. If you feel is better your way, then OK, I
> have no problems with moving it in pm.c.
> 

You don't need an other struct of_device_id array as you already have
all the _pm_init functions broken out by soc family.

Going further, for at91rm9200_pm_init and at91sam9_pm_init, maybe you
can simply enforce soc_pm.data.standby_mode = AT91_PM_STANDBY and
soc_pm.data.suspend_mode = AT91_PM_ULP0 instead of checking the modes.


> > 
> >>  static const char *const at91rm9200_dt_board_compat[] __initconst = {
> >> diff --git a/arch/arm/mach-at91/at91sam9.c b/arch/arm/mach-at91/at91sam9.c
> >> index 7e572189a5eb..683f2c35a116 100644
> >> --- a/arch/arm/mach-at91/at91sam9.c
> >> +++ b/arch/arm/mach-at91/at91sam9.c
> >> @@ -13,12 +13,19 @@
> >>  #include <asm/system_misc.h>
> >>
> >>  #include "generic.h"
> >> +#include "pm.h"
> >> +
> >> +/* AT91SAM9 valid PM modes. */
> >> +static const int at91sam9_pm_modes[] = {
> >> +     AT91_PM_STANDBY,
> >> +     AT91_PM_ULP0,
> >> +};
> >>
> >>  static void __init at91sam9_init(void)
> >>  {
> >>       of_platform_default_populate(NULL, NULL, NULL);
> >>
> >> -     at91sam9_pm_init();
> >> +     at91sam9_pm_init(at91sam9_pm_modes, ARRAY_SIZE(at91sam9_pm_modes));
> >>  }
> >>
> >>  static const char *const at91_dt_board_compat[] __initconst = {
> >> diff --git a/arch/arm/mach-at91/generic.h b/arch/arm/mach-at91/generic.h
> >> index 0a4cdcb4985b..610a12e5a71c 100644
> >> --- a/arch/arm/mach-at91/generic.h
> >> +++ b/arch/arm/mach-at91/generic.h
> >> @@ -9,17 +9,17 @@
> >>  #define _AT91_GENERIC_H
> >>
> >>  #ifdef CONFIG_PM
> >> -extern void __init at91rm9200_pm_init(void);
> >> -extern void __init at91sam9_pm_init(void);
> >> -extern void __init sam9x60_pm_init(void);
> >> -extern void __init sama5_pm_init(void);
> >> -extern void __init sama5d2_pm_init(void);
> >> +extern void __init at91rm9200_pm_init(const int *modes, int len);
> >> +extern void __init at91sam9_pm_init(const int *modes, int len);
> >> +extern void __init sam9x60_pm_init(const int *modes, int len);
> >> +extern void __init sama5_pm_init(const int *modes, int len);
> >> +extern void __init sama5d2_pm_init(const int *modes, int len);
> >>  #else
> >> -static inline void __init at91rm9200_pm_init(void) { }
> >> -static inline void __init at91sam9_pm_init(void) { }
> >> -static inline void __init sam9x60_pm_init(void) { }
> >> -static inline void __init sama5_pm_init(void) { }
> >> -static inline void __init sama5d2_pm_init(void) { }
> >> +static inline void __init at91rm9200_pm_init(const int *modes, int len) { }
> >> +static inline void __init at91sam9_pm_init(const int *modes, int len) { }
> >> +static inline void __init sam9x60_pm_init(const int *modes, int len) { }
> >> +static inline void __init sama5_pm_init(const int *modes, int len) { }
> >> +static inline void __init sama5d2_pm_init(const int *modes, int len) { }
> >>  #endif
> >>
> > 
> > Then this change is not necessary.
> > 
> >>  #endif /* _AT91_GENERIC_H */
> >> diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c
> >> index 04fdcbd57100..caf87efc7eeb 100644
> >> --- a/arch/arm/mach-at91/pm.c
> >> +++ b/arch/arm/mach-at91/pm.c
> >> @@ -785,6 +785,59 @@ static const struct of_device_id atmel_pmc_ids[] __initconst = {
> >>       { /* sentinel */ },
> >>  };
> >>
> >> +static void __init at91_pm_modes_validate(const int *modes, int len)
> >> +{
> >> +     u8 i, located = 0;
> >> +     int mode;
> >> +
> >> +#define STANDBY      BIT(0)
> >> +#define SUSPEND      BIT(1)
> >> +
> >> +     for (i = 0; i < len; i++) {
> >> +             if ((located & STANDBY) && (located & SUSPEND))
> >> +                     break;
> >> +
> >> +             if (modes[i] == soc_pm.data.standby_mode &&
> >> +                 !(located & STANDBY)) {
> >> +                     located |= STANDBY;
> >> +                     continue;
> >> +             }
> >> +
> >> +             if (modes[i] == soc_pm.data.suspend_mode &&
> >> +                 !(located & SUSPEND)) {
> >> +                     located |= SUSPEND;
> >> +                     continue;
> >> +             }
> >> +     }
> >> +
> >> +     if (!(located & STANDBY)) {
> >> +             if (soc_pm.data.suspend_mode == AT91_PM_STANDBY)
> >> +                     mode = AT91_PM_ULP0;
> >> +             else
> >> +                     mode = AT91_PM_STANDBY;
> >> +
> >> +             pr_warn("AT91: PM: %s mode not supported! Using %s.\n",
> >> +                     pm_modes[soc_pm.data.standby_mode].pattern,
> >> +                     pm_modes[mode].pattern);
> >> +             soc_pm.data.standby_mode = mode;
> >> +     }
> >> +
> >> +     if (!(located & SUSPEND)) {
> >> +             if (soc_pm.data.standby_mode == AT91_PM_ULP0)
> >> +                     mode = AT91_PM_STANDBY;
> >> +             else
> >> +                     mode = AT91_PM_ULP0;
> >> +
> >> +             pr_warn("AT91: PM: %s mode not supported! Using %s.\n",
> >> +                     pm_modes[soc_pm.data.suspend_mode].pattern,
> >> +                     pm_modes[mode].pattern);
> >> +             soc_pm.data.suspend_mode = mode;
> >> +     }
> >> +
> >> +#undef STANDBY
> >> +#undef SUSPEND
> > 
> > You should use two booleans instead of a bit array, this would not make
> > the code longer and will avoid this #def/#undef thing.
> 
> OK, I have no strong opinion on this. I'll switch to booleans.
> 
> > 
> >> +}
> >> +
> >>  static void __init at91_pm_init(void (*pm_idle)(void))
> >>  {
> >>       struct device_node *pmc_np;
> >> @@ -821,11 +874,12 @@ static void __init at91_pm_init(void (*pm_idle)(void))
> >>       }
> >>  }
> >>
> >> -void __init at91rm9200_pm_init(void)
> >> +void __init at91rm9200_pm_init(const int *modes, int len)
> >>  {
> >>       if (!IS_ENABLED(CONFIG_SOC_AT91RM9200))
> >>               return;
> >>
> >> +     at91_pm_modes_validate(modes, len);
> >>       at91_dt_ramc();
> >>
> >>       /*
> >> @@ -836,11 +890,12 @@ void __init at91rm9200_pm_init(void)
> >>       at91_pm_init(at91rm9200_idle);
> >>  }
> >>
> >> -void __init sam9x60_pm_init(void)
> >> +void __init sam9x60_pm_init(const int *modes, int len)
> >>  {
> >>       if (!IS_ENABLED(CONFIG_SOC_SAM9X60))
> >>               return;
> >>
> >> +     at91_pm_modes_validate(modes, len);
> >>       at91_pm_modes_init();
> >>       at91_dt_ramc();
> >>       at91_pm_init(at91sam9x60_idle);
> >> @@ -849,31 +904,33 @@ void __init sam9x60_pm_init(void)
> >>       soc_pm.config_pmc_ws = at91_sam9x60_config_pmc_ws;
> >>  }
> >>
> >> -void __init at91sam9_pm_init(void)
> >> +void __init at91sam9_pm_init(const int *modes, int len)
> >>  {
> >>       if (!IS_ENABLED(CONFIG_SOC_AT91SAM9))
> >>               return;
> >>
> >> +     at91_pm_modes_validate(modes, len);
> >>       at91_dt_ramc();
> >>       at91_pm_init(at91sam9_idle);
> >>  }
> >>
> >> -void __init sama5_pm_init(void)
> >> +void __init sama5_pm_init(const int *modes, int len)
> >>  {
> >>       if (!IS_ENABLED(CONFIG_SOC_SAMA5))
> >>               return;
> >>
> >> +     at91_pm_modes_validate(modes, len);
> >>       at91_dt_ramc();
> >>       at91_pm_init(NULL);
> >>  }
> >>
> >> -void __init sama5d2_pm_init(void)
> >> +void __init sama5d2_pm_init(const int *modes, int len)
> >>  {
> >>       if (!IS_ENABLED(CONFIG_SOC_SAMA5D2))
> >>               return;
> >>
> >> +     sama5_pm_init(modes, len);
> >>       at91_pm_modes_init();
> >> -     sama5_pm_init();
> >>
> >>       soc_pm.ws_ids = sama5d2_ws_ids;
> >>       soc_pm.config_shdwc_ws = at91_sama5d2_config_shdwc_ws;
> >> diff --git a/arch/arm/mach-at91/sam9x60.c b/arch/arm/mach-at91/sam9x60.c
> >> index d8c739d25458..d7c869c7b542 100644
> >> --- a/arch/arm/mach-at91/sam9x60.c
> >> +++ b/arch/arm/mach-at91/sam9x60.c
> >> @@ -14,12 +14,21 @@
> >>  #include <asm/system_misc.h>
> >>
> >>  #include "generic.h"
> >> +#include "pm.h"
> >> +
> >> +/* SAM9X60 valid PM modes. */
> >> +static const int sam9x60_pm_modes[] = {
> >> +     AT91_PM_STANDBY,
> >> +     AT91_PM_ULP0,
> >> +     AT91_PM_ULP0_FAST,
> >> +     AT91_PM_ULP1,
> >> +};
> >>
> >>  static void __init sam9x60_init(void)
> >>  {
> >>       of_platform_default_populate(NULL, NULL, NULL);
> >>
> >> -     sam9x60_pm_init();
> >> +     sam9x60_pm_init(sam9x60_pm_modes, ARRAY_SIZE(sam9x60_pm_modes));
> >>  }
> >>
> >>  static const char *const sam9x60_dt_board_compat[] __initconst = {
> >> diff --git a/arch/arm/mach-at91/sama5.c b/arch/arm/mach-at91/sama5.c
> >> index 89dab7cf01e8..7eb124612a10 100644
> >> --- a/arch/arm/mach-at91/sama5.c
> >> +++ b/arch/arm/mach-at91/sama5.c
> >> @@ -14,11 +14,19 @@
> >>  #include <asm/system_misc.h>
> >>
> >>  #include "generic.h"
> >> +#include "pm.h"
> >> +
> >> +/* SAMA5 valid PM modes. */
> >> +static const int sama5_pm_modes[] = {
> >> +     AT91_PM_STANDBY,
> >> +     AT91_PM_ULP0,
> >> +     AT91_PM_ULP0_FAST,
> >> +};
> >>
> >>  static void __init sama5_dt_device_init(void)
> >>  {
> >>       of_platform_default_populate(NULL, NULL, NULL);
> >> -     sama5_pm_init();
> >> +     sama5_pm_init(sama5_pm_modes, ARRAY_SIZE(sama5_pm_modes));
> >>  }
> >>
> >>  static const char *const sama5_dt_board_compat[] __initconst = {
> >> @@ -44,10 +52,19 @@ DT_MACHINE_START(sama5_alt_dt, "Atmel SAMA5")
> >>       .l2c_aux_mask   = ~0UL,
> >>  MACHINE_END
> >>
> >> +/* sama5d2 PM modes. */
> >> +static const int sama5d2_pm_modes[] = {
> >> +     AT91_PM_STANDBY,
> >> +     AT91_PM_ULP0,
> >> +     AT91_PM_ULP0_FAST,
> >> +     AT91_PM_ULP1,
> >> +     AT91_PM_BACKUP,
> >> +};
> >> +
> >>  static void __init sama5d2_init(void)
> >>  {
> >>       of_platform_default_populate(NULL, NULL, NULL);
> >> -     sama5d2_pm_init();
> >> +     sama5d2_pm_init(sama5d2_pm_modes, ARRAY_SIZE(sama5d2_pm_modes));
> >>  }

-- 
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com