[PATCH v5 00/13] AT91 pm cleanup for 3.20

[PATCH v5 00/13] AT91 pm cleanup for 3.20

[Wenyou Yang]

Hi Nicolas,

This version is rebased on the branch: at91-3.20-cleanup of the repository
	git://git.kernel.org/pub/scm/linux/kernel/git/nferre/linux-at91.git

It is purpose to clean up the PM code, includes the patches from Peter Rosin and Sylvain Rochet.

Since verifying the USB clock and USB PLL disabling before suspending to memory,
it aslo depends on the following patch serials from Sylvain:
	[PATCHv6 0/5] USB: gadget: atmel_usba_udc: Driver improvements
	[PATCHv7 0/6] USB: host: Atmel OHCI and EHCI drivers improvements

Removes CONFIG_AT91_SLOW_CLOCK config item to simply the PM config,
The suspend to standby mode uses the same sram function as the suspend to memory mode.
Remove some unused code.

Alexandr & Sylvain, Thank you very much for so many feedbacks.

Changes in v5:
 - Rebase the branch: at91-3.20-cleanup HEAD:fa9df37

Changes in v4:
 - Clear unused state argument in at91_pm_verify_clocks()
 - Remove pr_info("AT91:... slow_clock ? ..") in patch 07/13.

Changes in v3
 - Sylvain splits the patch in two
 - Add handling if no sram allocated for PM
 - Retain the STANDBY and SUSPEND_MEM select in at91_pm_enter.

Changes in v2:
 - Rebase on the at91-3.20-cleanup branch
 - Recover the verify clock condition, only for suspend to memory.
 - Collect ACK from Alexandre
 - Add the macro for PM mode

Peter Rosin (1):
  pm: at91: Workaround DDRSDRC self-refresh bug with LPDDR1 memories.

Sylvain Rochet (2):
  pm: at91: pm_slowclock: fix suspend/resume hang up in timeouts
  pm: at91: pm_slowclock: remove clocks which are already stopped when
    entering slow clock mode

Wenyou Yang (10):
  pm: at91: pm_slowclock: remove the unused code related with
    SLOWDOWN_MASTER_CLOCK
  pm: at91: move the copying the sram function to the sram
    initializationi phase
  ARM: at91: move select SRAM to ARCH_AT91
  pm: at91: remove the config item CONFIG_AT91_SLOW_CLOCK
  pm: at91: the standby mode uses the same sram function as the suspend
    to memory mode
  pm: at91: rename file name: pm_slowclock.S -->pm_suspend.S
  pm: at91: rename function name:
    at91_slow_clock()-->at91_pm_suspend_sram_fn
  pm: at91: remove the at91_xxx_standby() function definitions in the
    pm.h
  pm: at91: remove the data member at91_xxx_standby() of struct
    ramc_ids
  pm: at91: amend the pm_suspend entry for at91_cpuidle_device

 arch/arm/mach-at91/Kconfig         |   17 +-
 arch/arm/mach-at91/Makefile        |    2 +-
 arch/arm/mach-at91/pm.c            |  166 +++++++++---------
 arch/arm/mach-at91/pm.h            |  100 +----------
 arch/arm/mach-at91/pm_slowclock.S  |  323 ------------------------------------
 arch/arm/mach-at91/pm_suspend.S    |  277 +++++++++++++++++++++++++++++++
 include/soc/at91/at91sam9_ddrsdr.h |    2 +-
 7 files changed, 366 insertions(+), 521 deletions(-)
 delete mode 100644 arch/arm/mach-at91/pm_slowclock.S
 create mode 100644 arch/arm/mach-at91/pm_suspend.S

-- 
1.7.9.5

[PATCH v5 01/13] pm: at91: pm_slowclock: fix suspend/resume hang up in timeouts

[Wenyou Yang]

From: Sylvain Rochet <sylvain.rochet@finsecur.com>

Removed timeout on XTAL, PLL lock and Master Clock Ready, hang if
something went wrong instead of continuing in unknown condition. There
is not much we can do if a PLL lock never ends, we are running in SRAM
and we will not be able to connect back the sdram or ddram in order to
be able to fire up a message or just panic.

As a bonus, not decounting the timeout register in slow clock mode
reduce cumulated suspend time and resume time from ~17ms to ~15ms.

Signed-off-by: Sylvain Rochet <sylvain.rochet@finsecur.com>
---
 arch/arm/mach-at91/pm_slowclock.S |   33 ++++-----------------------------
 1 file changed, 4 insertions(+), 29 deletions(-)

diff --git a/arch/arm/mach-at91/pm_slowclock.S b/arch/arm/mach-at91/pm_slowclock.S
index 556151e..50744e7 100644
--- a/arch/arm/mach-at91/pm_slowclock.S
+++ b/arch/arm/mach-at91/pm_slowclock.S
@@ -25,11 +25,6 @@
  */
 #undef SLOWDOWN_MASTER_CLOCK
 
-#define MCKRDY_TIMEOUT		1000
-#define MOSCRDY_TIMEOUT 	1000
-#define PLLALOCK_TIMEOUT	1000
-#define PLLBLOCK_TIMEOUT	1000
-
 pmc	.req	r0
 sdramc	.req	r1
 ramc1	.req	r2
@@ -41,56 +36,36 @@ tmp2	.req	r5
  * Wait until master clock is ready (after switching master clock source)
  */
 	.macro wait_mckrdy
-	mov	tmp2, #MCKRDY_TIMEOUT
-1:	sub	tmp2, tmp2, #1
-	cmp	tmp2, #0
-	beq	2f
-	ldr	tmp1, [pmc, #AT91_PMC_SR]
+1:	ldr	tmp1, [pmc, #AT91_PMC_SR]
 	tst	tmp1, #AT91_PMC_MCKRDY
 	beq	1b
-2:
 	.endm
 
 /*
  * Wait until master oscillator has stabilized.
  */
 	.macro wait_moscrdy
-	mov	tmp2, #MOSCRDY_TIMEOUT
-1:	sub	tmp2, tmp2, #1
-	cmp	tmp2, #0
-	beq	2f
-	ldr	tmp1, [pmc, #AT91_PMC_SR]
+1:	ldr	tmp1, [pmc, #AT91_PMC_SR]
 	tst	tmp1, #AT91_PMC_MOSCS
 	beq	1b
-2:
 	.endm
 
 /*
  * Wait until PLLA has locked.
  */
 	.macro wait_pllalock
-	mov	tmp2, #PLLALOCK_TIMEOUT
-1:	sub	tmp2, tmp2, #1
-	cmp	tmp2, #0
-	beq	2f
-	ldr	tmp1, [pmc, #AT91_PMC_SR]
+1:	ldr	tmp1, [pmc, #AT91_PMC_SR]
 	tst	tmp1, #AT91_PMC_LOCKA
 	beq	1b
-2:
 	.endm
 
 /*
  * Wait until PLLB has locked.
  */
 	.macro wait_pllblock
-	mov	tmp2, #PLLBLOCK_TIMEOUT
-1:	sub	tmp2, tmp2, #1
-	cmp	tmp2, #0
-	beq	2f
-	ldr	tmp1, [pmc, #AT91_PMC_SR]
+1:	ldr	tmp1, [pmc, #AT91_PMC_SR]
 	tst	tmp1, #AT91_PMC_LOCKB
 	beq	1b
-2:
 	.endm
 
 	.text
-- 
1.7.9.5

[PATCH v5 02/13] pm: at91: pm_slowclock: remove clocks which are already stopped when entering slow clock mode

[Wenyou Yang]

From: Sylvain Rochet <sylvain.rochet@finsecur.com>

Assume USB PLL and PLL B are already stopped before entering sleep mode,
print a warning if this isn't the case.

Removed PLL B from slow clock code, all drivers are supposed to properly
unprepare clocks.

Signed-off-by: Sylvain Rochet <sylvain.rochet@finsecur.com>
---
 arch/arm/mach-at91/pm.c           |   12 ++++++++++++
 arch/arm/mach-at91/pm_slowclock.S |   31 -------------------------------
 2 files changed, 12 insertions(+), 31 deletions(-)

diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c
index af8d8af..daa998d 100644
--- a/arch/arm/mach-at91/pm.c
+++ b/arch/arm/mach-at91/pm.c
@@ -100,6 +100,18 @@ static int at91_pm_verify_clocks(void)
 		}
 	}
 
+	/* Drivers should have previously suspended USB PLL */
+	if (at91_pmc_read(AT91_CKGR_UCKR) & AT91_PMC_UPLLEN) {
+		pr_err("AT91: PM - Suspend-to-RAM with USB PLL running\n");
+		return 0;
+	}
+
+	/* Drivers should have previously suspended PLL B */
+	if (at91_pmc_read(AT91_PMC_SR) & AT91_PMC_LOCKB) {
+		pr_err("AT91: PM - Suspend-to-RAM with PLL B running\n");
+		return 0;
+	}
+
 	return 1;
 }
 
diff --git a/arch/arm/mach-at91/pm_slowclock.S b/arch/arm/mach-at91/pm_slowclock.S
index 50744e7..e2bfaf5 100644
--- a/arch/arm/mach-at91/pm_slowclock.S
+++ b/arch/arm/mach-at91/pm_slowclock.S
@@ -59,15 +59,6 @@ tmp2	.req	r5
 	beq	1b
 	.endm
 
-/*
- * Wait until PLLB has locked.
- */
-	.macro wait_pllblock
-1:	ldr	tmp1, [pmc, #AT91_PMC_SR]
-	tst	tmp1, #AT91_PMC_LOCKB
-	beq	1b
-	.endm
-
 	.text
 
 /* void at91_slow_clock(void __iomem *pmc, void __iomem *sdramc,
@@ -173,13 +164,6 @@ sdr_sr_done:
 	orr	tmp1, tmp1, #(1 << 29)		/* bit 29 always set */
 	str	tmp1, [pmc, #AT91_CKGR_PLLAR]
 
-	/* Save PLLB setting and disable it */
-	ldr	tmp1, [pmc, #AT91_CKGR_PLLBR]
-	str	tmp1, .saved_pllbr
-
-	mov	tmp1, #AT91_PMC_PLLCOUNT
-	str	tmp1, [pmc, #AT91_CKGR_PLLBR]
-
 	/* Turn off the main oscillator */
 	ldr	tmp1, [pmc, #AT91_CKGR_MOR]
 	bic	tmp1, tmp1, #AT91_PMC_MOSCEN
@@ -195,18 +179,6 @@ sdr_sr_done:
 
 	wait_moscrdy
 
-	/* Restore PLLB setting */
-	ldr	tmp1, .saved_pllbr
-	str	tmp1, [pmc, #AT91_CKGR_PLLBR]
-
-	tst	tmp1, #(AT91_PMC_MUL &  0xff0000)
-	bne	1f
-	tst	tmp1, #(AT91_PMC_MUL & ~0xff0000)
-	beq	2f
-1:
-	wait_pllblock
-2:
-
 	/* Restore PLLA setting */
 	ldr	tmp1, .saved_pllar
 	str	tmp1, [pmc, #AT91_CKGR_PLLAR]
@@ -285,9 +257,6 @@ ram_restored:
 .saved_pllar:
 	.word 0
 
-.saved_pllbr:
-	.word 0
-
 .saved_sam9_lpr:
 	.word 0
 
-- 
1.7.9.5

[PATCH v5 03/13] pm: at91: Workaround DDRSDRC self-refresh bug with LPDDR1 memories.

[Wenyou Yang]

From: Peter Rosin <peda@axentia.se>

The DDRSDR controller fails miserably to put LPDDR1 memories in
self-refresh. Force the controller to think it has DDR2 memories
during the self-refresh period, as the DDR2 self-refresh spec is
equivalent to LPDDR1, and is correctly implemented in the
controller.

Assume that the second controller has the same fault, but that is
untested.

Signed-off-by: Peter Rosin <peda@axentia.se>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
 arch/arm/mach-at91/pm_slowclock.S  |   43 +++++++++++++++++++++++++++++++-----
 include/soc/at91/at91sam9_ddrsdr.h |    2 +-
 2 files changed, 39 insertions(+), 6 deletions(-)

diff --git a/arch/arm/mach-at91/pm_slowclock.S b/arch/arm/mach-at91/pm_slowclock.S
index e2bfaf5..1155217 100644
--- a/arch/arm/mach-at91/pm_slowclock.S
+++ b/arch/arm/mach-at91/pm_slowclock.S
@@ -100,6 +100,16 @@ ddr_sr_enable:
 	cmp	memctrl, #AT91_MEMCTRL_DDRSDR
 	bne	sdr_sr_enable
 
+	/* LPDDR1 --> force DDR2 mode during self-refresh */
+	ldr	tmp1, [sdramc, #AT91_DDRSDRC_MDR]
+	str	tmp1, .saved_sam9_mdr
+	bic	tmp1, tmp1, #~AT91_DDRSDRC_MD
+	cmp	tmp1, #AT91_DDRSDRC_MD_LOW_POWER_DDR
+	ldreq	tmp1, [sdramc, #AT91_DDRSDRC_MDR]
+	biceq	tmp1, tmp1, #AT91_DDRSDRC_MD
+	orreq	tmp1, tmp1, #AT91_DDRSDRC_MD_DDR2
+	streq	tmp1, [sdramc, #AT91_DDRSDRC_MDR]
+
 	/* prepare for DDRAM self-refresh mode */
 	ldr	tmp1, [sdramc, #AT91_DDRSDRC_LPR]
 	str	tmp1, .saved_sam9_lpr
@@ -108,14 +118,26 @@ ddr_sr_enable:
 
 	/* figure out if we use the second ram controller */
 	cmp	ramc1, #0
-	ldrne	tmp2, [ramc1, #AT91_DDRSDRC_LPR]
-	strne	tmp2, .saved_sam9_lpr1
-	bicne	tmp2, #AT91_DDRSDRC_LPCB
-	orrne	tmp2, #AT91_DDRSDRC_LPCB_SELF_REFRESH
+	beq	ddr_no_2nd_ctrl
+
+	ldr	tmp2, [ramc1, #AT91_DDRSDRC_MDR]
+	str	tmp2, .saved_sam9_mdr1
+	bic	tmp2, tmp2, #~AT91_DDRSDRC_MD
+	cmp	tmp2, #AT91_DDRSDRC_MD_LOW_POWER_DDR
+	ldreq	tmp2, [ramc1, #AT91_DDRSDRC_MDR]
+	biceq	tmp2, tmp2, #AT91_DDRSDRC_MD
+	orreq	tmp2, tmp2, #AT91_DDRSDRC_MD_DDR2
+	streq	tmp2, [ramc1, #AT91_DDRSDRC_MDR]
+
+	ldr	tmp2, [ramc1, #AT91_DDRSDRC_LPR]
+	str	tmp2, .saved_sam9_lpr1
+	bic	tmp2, #AT91_DDRSDRC_LPCB
+	orr	tmp2, #AT91_DDRSDRC_LPCB_SELF_REFRESH
 
 	/* Enable DDRAM self-refresh mode */
+	str	tmp2, [ramc1, #AT91_DDRSDRC_LPR]
+ddr_no_2nd_ctrl:
 	str	tmp1, [sdramc, #AT91_DDRSDRC_LPR]
-	strne	tmp2, [ramc1, #AT91_DDRSDRC_LPR]
 
 	b	sdr_sr_done
 
@@ -227,12 +249,17 @@ sdr_sr_done:
 	 */
 	cmp	memctrl, #AT91_MEMCTRL_DDRSDR
 	bne	sdr_en_restore
+	/* Restore MDR in case of LPDDR1 */
+	ldr	tmp1, .saved_sam9_mdr
+	str	tmp1, [sdramc, #AT91_DDRSDRC_MDR]
 	/* Restore LPR on AT91 with DDRAM */
 	ldr	tmp1, .saved_sam9_lpr
 	str	tmp1, [sdramc, #AT91_DDRSDRC_LPR]
 
 	/* if we use the second ram controller */
 	cmp	ramc1, #0
+	ldrne	tmp2, .saved_sam9_mdr1
+	strne	tmp2, [ramc1, #AT91_DDRSDRC_MDR]
 	ldrne	tmp2, .saved_sam9_lpr1
 	strne	tmp2, [ramc1, #AT91_DDRSDRC_LPR]
 
@@ -263,5 +290,11 @@ ram_restored:
 .saved_sam9_lpr1:
 	.word 0
 
+.saved_sam9_mdr:
+	.word 0
+
+.saved_sam9_mdr1:
+	.word 0
+
 ENTRY(at91_slow_clock_sz)
 	.word .-at91_slow_clock
diff --git a/include/soc/at91/at91sam9_ddrsdr.h b/include/soc/at91/at91sam9_ddrsdr.h
index 0210797..dc10c52 100644
--- a/include/soc/at91/at91sam9_ddrsdr.h
+++ b/include/soc/at91/at91sam9_ddrsdr.h
@@ -92,7 +92,7 @@
 #define		AT91_DDRSDRC_UPD_MR	(3 << 20)	 /* Update load mode register and extended mode register */
 
 #define AT91_DDRSDRC_MDR	0x20	/* Memory Device Register */
-#define		AT91_DDRSDRC_MD		(3 << 0)		/* Memory Device Type */
+#define		AT91_DDRSDRC_MD		(7 << 0)	/* Memory Device Type */
 #define			AT91_DDRSDRC_MD_SDR		0
 #define			AT91_DDRSDRC_MD_LOW_POWER_SDR	1
 #define			AT91_DDRSDRC_MD_LOW_POWER_DDR	3
-- 
1.7.9.5

[PATCH v5 04/13] pm: at91: pm_slowclock: remove the unused code related with SLOWDOWN_MASTER_CLOCK

[Wenyou Yang]

The SLOWDOWN_MASTER_CLOCK definition is not used, remove the redundant code.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
---
 arch/arm/mach-at91/pm_slowclock.S |   37 -------------------------------------
 1 file changed, 37 deletions(-)

diff --git a/arch/arm/mach-at91/pm_slowclock.S b/arch/arm/mach-at91/pm_slowclock.S
index 1155217..4e55665 100644
--- a/arch/arm/mach-at91/pm_slowclock.S
+++ b/arch/arm/mach-at91/pm_slowclock.S
@@ -11,20 +11,11 @@
  * published by the Free Software Foundation.
  *
  */
-
 #include <linux/linkage.h>
 #include <linux/clk/at91_pmc.h>
 #include <mach/hardware.h>
 #include <mach/at91_ramc.h>
 
-/*
- * When SLOWDOWN_MASTER_CLOCK is defined we will also slow down the Master
- * clock during suspend by adjusting its prescalar and divisor.
- * NOTE: This hasn't been shown to be stable on SAM9s; and on the RM9200 there
- *       are errata regarding adjusting the prescalar and divisor.
- */
-#undef SLOWDOWN_MASTER_CLOCK
-
 pmc	.req	r0
 sdramc	.req	r1
 ramc1	.req	r2
@@ -166,18 +157,6 @@ sdr_sr_done:
 
 	wait_mckrdy
 
-#ifdef SLOWDOWN_MASTER_CLOCK
-	/*
-	 * Set the Master Clock PRES and MDIV fields.
-	 *
-	 * See AT91RM9200 errata #27 and #28 for details.
-	 */
-	mov	tmp1, #0
-	str	tmp1, [pmc, #AT91_PMC_MCKR]
-
-	wait_mckrdy
-#endif
-
 	/* Save PLLA setting and disable it */
 	ldr	tmp1, [pmc, #AT91_CKGR_PLLAR]
 	str	tmp1, .saved_pllar
@@ -213,22 +192,6 @@ sdr_sr_done:
 	wait_pllalock
 4:
 
-#ifdef SLOWDOWN_MASTER_CLOCK
-	/*
-	 * First set PRES if it was not 0,
-	 * than set CSS and MDIV fields.
-	 *
-	 * See AT91RM9200 errata #27 and #28 for details.
-	 */
-	ldr	tmp1, .saved_mckr
-	tst	tmp1, #AT91_PMC_PRES
-	beq	2f
-	and	tmp1, tmp1, #AT91_PMC_PRES
-	str	tmp1, [pmc, #AT91_PMC_MCKR]
-
-	wait_mckrdy
-#endif
-
 	/*
 	 * Restore master clock setting
 	 */
-- 
1.7.9.5

[PATCH v5 05/13] pm: at91: move the copying the sram function to the sram initializationi phase

[Wenyou Yang]

To decrease the suspend time, move the copying the sram function
to the sram initialization phase, instead of every time go to suspend.

In the meanwhile, if there is no sram allocated for PM, the PM is not supported.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
---
 arch/arm/mach-at91/pm.c |   12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c
index daa998d..6df0152 100644
--- a/arch/arm/mach-at91/pm.c
+++ b/arch/arm/mach-at91/pm.c
@@ -163,10 +163,6 @@ static int at91_pm_enter(suspend_state_t state)
 			 * turning off the main oscillator; reverse on wakeup.
 			 */
 			if (slow_clock) {
-#ifdef CONFIG_AT91_SLOW_CLOCK
-				/* copy slow_clock handler to SRAM, and call it */
-				memcpy(slow_clock, at91_slow_clock, at91_slow_clock_sz);
-#endif
 				slow_clock(at91_pmc_base, at91_ramc_base[0],
 					   at91_ramc_base[1],
 					   at91_pm_data.memctrl);
@@ -311,6 +307,9 @@ static void __init at91_pm_sram_init(void)
 	sram_pbase = gen_pool_virt_to_phys(sram_pool, sram_base);
 	slow_clock = __arm_ioremap_exec(sram_pbase, at91_slow_clock_sz, false);
 
+	/* Copy the slow_clock handler to SRAM */
+	memcpy(slow_clock, at91_slow_clock, at91_slow_clock_sz);
+
 put_node:
 	of_node_put(node);
 }
@@ -328,7 +327,10 @@ static void __init at91_pm_init(void)
 	if (at91_cpuidle_device.dev.platform_data)
 		platform_device_register(&at91_cpuidle_device);
 
-	suspend_set_ops(&at91_pm_ops);
+	if (slow_clock)
+		suspend_set_ops(&at91_pm_ops);
+	else
+		pr_info("AT91: PM : Not supported, due to no sram allocated\n");
 }
 
 void __init at91rm9200_pm_init(void)
-- 
1.7.9.5

Re: [PATCH v5 05/13] pm: at91: move the copying the sram function to the sram initializationi phase

[Sergei Shtylyov]

Hello.

On 1/29/2015 9:38 AM, Wenyou Yang wrote:

> To decrease the suspend time, move the copying the sram function
> to the sram initialization phase, instead of every time go to suspend.

> In the meanwhile, if there is no sram allocated for PM, the PM is not supported.

> Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
> Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
> ---
>   arch/arm/mach-at91/pm.c |   12 +++++++-----
>   1 file changed, 7 insertions(+), 5 deletions(-)

> diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c
> index daa998d..6df0152 100644
> --- a/arch/arm/mach-at91/pm.c
> +++ b/arch/arm/mach-at91/pm.c
> @@ -163,10 +163,6 @@ static int at91_pm_enter(suspend_state_t state)
>   			 * turning off the main oscillator; reverse on wakeup.
>   			 */
>   			if (slow_clock) {
> -#ifdef CONFIG_AT91_SLOW_CLOCK
> -				/* copy slow_clock handler to SRAM, and call it */
> -				memcpy(slow_clock, at91_slow_clock, at91_slow_clock_sz);
> -#endif
>   				slow_clock(at91_pmc_base, at91_ramc_base[0],
>   					   at91_ramc_base[1],
>   					   at91_pm_data.memctrl);
> @@ -311,6 +307,9 @@ static void __init at91_pm_sram_init(void)
>   	sram_pbase = gen_pool_virt_to_phys(sram_pool, sram_base);
>   	slow_clock = __arm_ioremap_exec(sram_pbase, at91_slow_clock_sz, false);
>
> +	/* Copy the slow_clock handler to SRAM */
> +	memcpy(slow_clock, at91_slow_clock, at91_slow_clock_sz);

    AFAIU (looking at the code above and below), __arm_ioremap_exec() can 
return NULL and in this case memcpy() will cause kernel oops.

> @@ -328,7 +327,10 @@ static void __init at91_pm_init(void)
>   	if (at91_cpuidle_device.dev.platform_data)
>   		platform_device_register(&at91_cpuidle_device);
>
> -	suspend_set_ops(&at91_pm_ops);
> +	if (slow_clock)
> +		suspend_set_ops(&at91_pm_ops);
> +	else
> +		pr_info("AT91: PM : Not supported, due to no sram allocated\n");

    I'd suggest upper-casing "sram". And removing of colon after "PM".

[...]

WBR, Sergei

RE: [PATCH v5 05/13] pm: at91: move the copying the sram function to the sram initializationi phase

[Yang, Wenyou]

Hi Sergei,

Thank you for your review and suggestion.

> -----Original Message-----
> From: Sergei Shtylyov [mailto:sergei.shtylyov@cogentembedded.com]
> Sent: Thursday, January 29, 2015 6:11 PM
> To: Yang, Wenyou; Ferre, Nicolas; linux@arm.linux.org.uk
> Cc: linux-arm-kernel@lists.infradead.org; linux-kernel@vger.kernel.org;
> alexandre.belloni@free-electrons.com; sylvain.rochet@finsecur.com;
> peda@axentia.se; linux@maxim.org.za
> Subject: Re: [PATCH v5 05/13] pm: at91: move the copying the sram function to
> the sram initializationi phase
> 
> Hello.
> 
> On 1/29/2015 9:38 AM, Wenyou Yang wrote:
> 
> > To decrease the suspend time, move the copying the sram function to
> > the sram initialization phase, instead of every time go to suspend.
> 
> > In the meanwhile, if there is no sram allocated for PM, the PM is not supported.
> 
> > Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
> > Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
> > ---
> >   arch/arm/mach-at91/pm.c |   12 +++++++-----
> >   1 file changed, 7 insertions(+), 5 deletions(-)
> 
> > diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c index
> > daa998d..6df0152 100644
> > --- a/arch/arm/mach-at91/pm.c
> > +++ b/arch/arm/mach-at91/pm.c
> > @@ -163,10 +163,6 @@ static int at91_pm_enter(suspend_state_t state)
> >   			 * turning off the main oscillator; reverse on wakeup.
> >   			 */
> >   			if (slow_clock) {
> > -#ifdef CONFIG_AT91_SLOW_CLOCK
> > -				/* copy slow_clock handler to SRAM, and call it */
> > -				memcpy(slow_clock, at91_slow_clock,
> at91_slow_clock_sz);
> > -#endif
> >   				slow_clock(at91_pmc_base, at91_ramc_base[0],
> >   					   at91_ramc_base[1],
> >   					   at91_pm_data.memctrl);
> > @@ -311,6 +307,9 @@ static void __init at91_pm_sram_init(void)
> >   	sram_pbase = gen_pool_virt_to_phys(sram_pool, sram_base);
> >   	slow_clock = __arm_ioremap_exec(sram_pbase, at91_slow_clock_sz,
> > false);
> >
> > +	/* Copy the slow_clock handler to SRAM */
> > +	memcpy(slow_clock, at91_slow_clock, at91_slow_clock_sz);
> 
>     AFAIU (looking at the code above and below), __arm_ioremap_exec() can return
> NULL and in this case memcpy() will cause kernel oops.
Will add a condition before copying 
	if (sram_pbase)

> 
> > @@ -328,7 +327,10 @@ static void __init at91_pm_init(void)
> >   	if (at91_cpuidle_device.dev.platform_data)
> >   		platform_device_register(&at91_cpuidle_device);
> >
> > -	suspend_set_ops(&at91_pm_ops);
> > +	if (slow_clock)
> > +		suspend_set_ops(&at91_pm_ops);
> > +	else
> > +		pr_info("AT91: PM : Not supported, due to no sram allocated\n");
> 
>     I'd suggest upper-casing "sram". And removing of colon after "PM".
Will change.

> 
> [...]
> 
> WBR, Sergei

Best Regards,
Wenyou Yang

Re: [PATCH v5 05/13] pm: at91: move the copying the sram function to the sram initializationi phase

[Sergei Shtylyov]

Hello.

On 1/30/2015 9:54 AM, Yang, Wenyou wrote:

> Thank you for your review and suggestion.

    Not at all.

>> -----Original Message-----
>> From: Sergei Shtylyov [mailto:sergei.shtylyov@cogentembedded.com]
>> Sent: Thursday, January 29, 2015 6:11 PM
>> To: Yang, Wenyou; Ferre, Nicolas; linux@arm.linux.org.uk
>> Cc: linux-arm-kernel@lists.infradead.org; linux-kernel@vger.kernel.org;
>> alexandre.belloni@free-electrons.com; sylvain.rochet@finsecur.com;
>> peda@axentia.se; linux@maxim.org.za
>> Subject: Re: [PATCH v5 05/13] pm: at91: move the copying the sram function to
>> the sram initializationi phase

>> Hello.

>> On 1/29/2015 9:38 AM, Wenyou Yang wrote:

>>> To decrease the suspend time, move the copying the sram function to
>>> the sram initialization phase, instead of every time go to suspend.

>>> In the meanwhile, if there is no sram allocated for PM, the PM is not supported.

>>> Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
>>> Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
>>> ---
>>>    arch/arm/mach-at91/pm.c |   12 +++++++-----
>>>    1 file changed, 7 insertions(+), 5 deletions(-)

>>> diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c index
>>> daa998d..6df0152 100644
>>> --- a/arch/arm/mach-at91/pm.c
>>> +++ b/arch/arm/mach-at91/pm.c
>>> @@ -163,10 +163,6 @@ static int at91_pm_enter(suspend_state_t state)
>>>    			 * turning off the main oscillator; reverse on wakeup.
>>>    			 */
>>>    			if (slow_clock) {
>>> -#ifdef CONFIG_AT91_SLOW_CLOCK
>>> -				/* copy slow_clock handler to SRAM, and call it */
>>> -				memcpy(slow_clock, at91_slow_clock,
>>> at91_slow_clock_sz);
>>> -#endif
>>>    				slow_clock(at91_pmc_base, at91_ramc_base[0],
>>>    					   at91_ramc_base[1],
>>>    					   at91_pm_data.memctrl);
>>> @@ -311,6 +307,9 @@ static void __init at91_pm_sram_init(void)
>>>    	sram_pbase = gen_pool_virt_to_phys(sram_pool, sram_base);
>>>    	slow_clock = __arm_ioremap_exec(sram_pbase, at91_slow_clock_sz,
>>> false);
>>>
>>> +	/* Copy the slow_clock handler to SRAM */
>>> +	memcpy(slow_clock, at91_slow_clock, at91_slow_clock_sz);

>>      AFAIU (looking at the code above and below), __arm_ioremap_exec() can return
>> NULL and in this case memcpy() will cause kernel oops.

> Will add a condition before copying
> 	if (sram_pbase)

    I rather meant *if* (slow_clock).

[...]

> Best Regards,
> Wenyou Yang

WBR, Sergei

[PATCH v5 06/13] ARM: at91: move select SRAM to ARCH_AT91

[Wenyou Yang]

Because the CONFIG_AT91_SLOW_CLOCK will be removed
to simply the PM config, so move select SRAM.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
---
 arch/arm/mach-at91/Kconfig |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/arm/mach-at91/Kconfig b/arch/arm/mach-at91/Kconfig
index c6740e3..6b9e685 100644
--- a/arch/arm/mach-at91/Kconfig
+++ b/arch/arm/mach-at91/Kconfig
@@ -25,6 +25,7 @@ config SOC_SAMA5
 	select MEMORY
 	select ATMEL_SDRAMC
 	select PHYLIB if NETDEVICES
+	select SRAM if PM
 
 menu "Atmel AT91 System-on-Chip"
 
@@ -82,6 +83,7 @@ config SOC_AT91RM9200
 	select CPU_ARM920T
 	select GENERIC_CLOCKEVENTS
 	select HAVE_AT91_USB_CLK
+	select SRAM if PM
 
 config SOC_AT91SAM9
 	bool "AT91SAM9"
@@ -95,6 +97,7 @@ config SOC_AT91SAM9
 	select HAVE_AT91_UTMI
 	select HAVE_FB_ATMEL
 	select MEMORY
+	select SRAM if PM
 	help
 	  Select this if you are using one of those Atmel SoC:
 	    AT91SAM9260
@@ -119,7 +122,6 @@ comment "AT91 Feature Selections"
 
 config AT91_SLOW_CLOCK
 	bool "Suspend-to-RAM disables main oscillator"
-	select SRAM
 	depends on SUSPEND
 	help
 	  Select this if you want Suspend-to-RAM to save the most power
-- 
1.7.9.5

[PATCH v5 07/13] pm: at91: remove the config item CONFIG_AT91_SLOW_CLOCK

[Wenyou Yang]

The slow clock always exists, for the suspend to memory mode,
the master clock always switch to the slow clock.

To simplify the PM config, remove this config item, remove
the definition code as well.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
---
 arch/arm/mach-at91/Kconfig  |   13 -------------
 arch/arm/mach-at91/Makefile |    2 +-
 arch/arm/mach-at91/pm.c     |    9 ---------
 3 files changed, 1 insertion(+), 23 deletions(-)

diff --git a/arch/arm/mach-at91/Kconfig b/arch/arm/mach-at91/Kconfig
index 6b9e685..3a5e46a 100644
--- a/arch/arm/mach-at91/Kconfig
+++ b/arch/arm/mach-at91/Kconfig
@@ -120,19 +120,6 @@ endif # SOC_SAM_V4_V5
 
 comment "AT91 Feature Selections"
 
-config AT91_SLOW_CLOCK
-	bool "Suspend-to-RAM disables main oscillator"
-	depends on SUSPEND
-	help
-	  Select this if you want Suspend-to-RAM to save the most power
-	  possible (without powering off the CPU) by disabling the PLLs
-	  and main oscillator so that only the 32 KiHz clock is available.
-
-	  When only that slow-clock is available, some peripherals lose
-	  functionality.  Many can't issue wakeup events unless faster
-	  clocks are available.  Some lose their operating state and
-	  need to be completely re-initialized.
-
 config AT91_TIMER_HZ
        int "Kernel HZ (jiffies per second)"
        range 32 1024
diff --git a/arch/arm/mach-at91/Makefile b/arch/arm/mach-at91/Makefile
index 827fdbc..103c256 100644
--- a/arch/arm/mach-at91/Makefile
+++ b/arch/arm/mach-at91/Makefile
@@ -13,7 +13,7 @@ obj-$(CONFIG_SOC_SAMA5)		+= sama5.o
 
 # Power Management
 obj-$(CONFIG_PM)		+= pm.o
-obj-$(CONFIG_AT91_SLOW_CLOCK)	+= pm_slowclock.o
+obj-$(CONFIG_PM)		+= pm_slowclock.o
 
 ifeq ($(CONFIG_PM_DEBUG),y)
 CFLAGS_pm.o += -DDEBUG
diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c
index 6df0152..d2a64cc 100644
--- a/arch/arm/mach-at91/pm.c
+++ b/arch/arm/mach-at91/pm.c
@@ -135,11 +135,9 @@ EXPORT_SYMBOL(at91_suspend_entering_slow_clock);
 static void (*slow_clock)(void __iomem *pmc, void __iomem *ramc0,
 			  void __iomem *ramc1, int memctrl);
 
-#ifdef CONFIG_AT91_SLOW_CLOCK
 extern void at91_slow_clock(void __iomem *pmc, void __iomem *ramc0,
 			    void __iomem *ramc1, int memctrl);
 extern u32 at91_slow_clock_sz;
-#endif
 
 static int at91_pm_enter(suspend_state_t state)
 {
@@ -271,7 +269,6 @@ static void at91_dt_ramc(void)
 	at91_pm_set_standby(standby);
 }
 
-#ifdef CONFIG_AT91_SLOW_CLOCK
 static void __init at91_pm_sram_init(void)
 {
 	struct gen_pool *sram_pool;
@@ -313,16 +310,10 @@ static void __init at91_pm_sram_init(void)
 put_node:
 	of_node_put(node);
 }
-#endif
-
 
 static void __init at91_pm_init(void)
 {
-#ifdef CONFIG_AT91_SLOW_CLOCK
 	at91_pm_sram_init();
-#endif
-
-	pr_info("AT91: Power Management%s\n", (slow_clock ? " (with slow clock mode)" : ""));
 
 	if (at91_cpuidle_device.dev.platform_data)
 		platform_device_register(&at91_cpuidle_device);
-- 
1.7.9.5

[PATCH v5 08/13] pm: at91: the standby mode uses the same sram function as the suspend to memory mode

[Wenyou Yang]

To simply the PM code, the suspend to standby mode uses the same sram function
as the suspend to memory mode, running in the internal SRAM,
instead of the respective code for each mode.

But for the suspend to standby mode, the master clock doesn't
switch to the slow clock,  and the main oscillator doesn't
turn off as well.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
---
 arch/arm/mach-at91/pm.c           |   85 +++++++++++++++++--------------------
 arch/arm/mach-at91/pm.h           |    7 +++
 arch/arm/mach-at91/pm_slowclock.S |   18 ++++++++
 3 files changed, 64 insertions(+), 46 deletions(-)

diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c
index d2a64cc..c3a697f 100644
--- a/arch/arm/mach-at91/pm.c
+++ b/arch/arm/mach-at91/pm.c
@@ -139,62 +139,55 @@ extern void at91_slow_clock(void __iomem *pmc, void __iomem *ramc0,
 			    void __iomem *ramc1, int memctrl);
 extern u32 at91_slow_clock_sz;
 
+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;
+
+	slow_clock(at91_pmc_base, at91_ramc_base[0],
+			at91_ramc_base[1], pm_data);
+}
+
 static int at91_pm_enter(suspend_state_t state)
 {
 	at91_pinctrl_gpio_suspend();
 
 	switch (state) {
+	/*
+	 * Suspend-to-RAM is like STANDBY plus slow clock mode, so
+	 * drivers must suspend more deeply, the master clock switches
+	 * to the clk32k and turns off the main oscillator
+	 */
+	case PM_SUSPEND_MEM:
 		/*
-		 * Suspend-to-RAM is like STANDBY plus slow clock mode, so
-		 * drivers must suspend more deeply:  only the master clock
-		 * controller may be using the main oscillator.
+		 * Ensure that clocks are in a valid state.
 		 */
-		case PM_SUSPEND_MEM:
-			/*
-			 * Ensure that clocks are in a valid state.
-			 */
-			if (!at91_pm_verify_clocks())
-				goto error;
-
-			/*
-			 * Enter slow clock mode by switching over to clk32k and
-			 * turning off the main oscillator; reverse on wakeup.
-			 */
-			if (slow_clock) {
-				slow_clock(at91_pmc_base, at91_ramc_base[0],
-					   at91_ramc_base[1],
-					   at91_pm_data.memctrl);
-				break;
-			} else {
-				pr_info("AT91: PM - no slow clock mode enabled ...\n");
-				/* FALLTHROUGH leaving master clock alone */
-			}
+		if (!at91_pm_verify_clocks())
+			goto error;
 
-		/*
-		 * STANDBY mode has *all* drivers suspended; ignores irqs not
-		 * marked as 'wakeup' event sources; and reduces DRAM power.
-		 * But otherwise it's identical to PM_SUSPEND_ON:  cpu idle, and
-		 * nothing fancy done with main or cpu clocks.
-		 */
-		case PM_SUSPEND_STANDBY:
-			/*
-			 * NOTE: the Wait-for-Interrupt instruction needs to be
-			 * in icache so no SDRAM accesses are needed until the
-			 * wakeup IRQ occurs and self-refresh is terminated.
-			 * For ARM 926 based chips, this requirement is weaker
-			 * as at91sam9 can access a RAM in self-refresh mode.
-			 */
-			if (at91_pm_standby)
-				at91_pm_standby();
-			break;
+		at91_pm_suspend(state);
 
-		case PM_SUSPEND_ON:
-			cpu_do_idle();
-			break;
+		break;
 
-		default:
-			pr_debug("AT91: PM - bogus suspend state %d\n", state);
-			goto error;
+	/*
+	 * STANDBY mode has *all* drivers suspended; ignores irqs not
+	 * marked as 'wakeup' event sources; and reduces DRAM power.
+	 * But otherwise it's identical to PM_SUSPEND_ON:  cpu idle, and
+	 * nothing fancy done with main or cpu clocks.
+	 */
+	case PM_SUSPEND_STANDBY:
+		at91_pm_suspend(state);
+		break;
+
+	case PM_SUSPEND_ON:
+		cpu_do_idle();
+		break;
+
+	default:
+		pr_debug("AT91: PM - bogus suspend state %d\n", state);
+		goto error;
 	}
 
 error:
diff --git a/arch/arm/mach-at91/pm.h b/arch/arm/mach-at91/pm.h
index d2c8996..5bc9c33 100644
--- a/arch/arm/mach-at91/pm.h
+++ b/arch/arm/mach-at91/pm.h
@@ -15,6 +15,13 @@
 
 #include <mach/at91_ramc.h>
 
+#define	AT91_PM_MEMCTRL_MASK	0x0f
+#define	AT91_PM_MODE_OFFSET	4
+#define	AT91_PM_MODE_MASK	0x0f
+#define	AT91_PM_MODE(x)		(((x) & AT91_PM_MODE_MASK) << AT91_PM_MODE_OFFSET)
+
+#define	AT91_PM_SLOW_CLOCK	0x01
+
 #ifdef CONFIG_PM
 extern void at91_pm_set_standby(void (*at91_standby)(void));
 #else
diff --git a/arch/arm/mach-at91/pm_slowclock.S b/arch/arm/mach-at91/pm_slowclock.S
index 4e55665..f56d114 100644
--- a/arch/arm/mach-at91/pm_slowclock.S
+++ b/arch/arm/mach-at91/pm_slowclock.S
@@ -16,12 +16,15 @@
 #include <mach/hardware.h>
 #include <mach/at91_ramc.h>
 
+#include "pm.h"
+
 pmc	.req	r0
 sdramc	.req	r1
 ramc1	.req	r2
 memctrl	.req	r3
 tmp1	.req	r4
 tmp2	.req	r5
+mode	.req	r6
 
 /*
  * Wait until master clock is ready (after switching master clock source)
@@ -73,6 +76,13 @@ ENTRY(at91_slow_clock)
 	mov	tmp1, #0
 	mcr	p15, 0, tmp1, c7, c10, 4
 
+	mov	tmp1, memctrl
+	mov	tmp2, tmp1, lsr#AT91_PM_MODE_OFFSET
+	and	mode, tmp2, #AT91_PM_MODE_MASK
+
+	mov	tmp1, memctrl
+	and	memctrl, tmp1, #AT91_PM_MEMCTRL_MASK
+
 	cmp	memctrl, #AT91_MEMCTRL_MC
 	bne	ddr_sr_enable
 
@@ -145,6 +155,9 @@ sdr_sr_enable:
 	str	tmp1, [sdramc, #AT91_SDRAMC_LPR]
 
 sdr_sr_done:
+	tst	mode, #AT91_PM_SLOW_CLOCK
+	beq	skip_disable_main_clock
+
 	/* Save Master clock setting */
 	ldr	tmp1, [pmc, #AT91_PMC_MCKR]
 	str	tmp1, .saved_mckr
@@ -170,9 +183,13 @@ sdr_sr_done:
 	bic	tmp1, tmp1, #AT91_PMC_MOSCEN
 	str	tmp1, [pmc, #AT91_CKGR_MOR]
 
+skip_disable_main_clock:
 	/* Wait for interrupt */
 	mcr	p15, 0, tmp1, c7, c0, 4
 
+	tst	mode, #AT91_PM_SLOW_CLOCK
+	beq	skip_enable_main_clock
+
 	/* Turn on the main oscillator */
 	ldr	tmp1, [pmc, #AT91_CKGR_MOR]
 	orr	tmp1, tmp1, #AT91_PMC_MOSCEN
@@ -200,6 +217,7 @@ sdr_sr_done:
 
 	wait_mckrdy
 
+skip_enable_main_clock:
 	/*
 	 * at91rm9200 Memory controller
 	 * Do nothing - self-refresh is automatically disabled.
-- 
1.7.9.5

[PATCH v5 09/13] pm: at91: rename file name: pm_slowclock.S -->pm_suspend.S

[Wenyou Yang]

Because the sram function is used for the suspend to standby mode as well,
more than suspend to memory, so renaming is more elegant.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
---
 arch/arm/mach-at91/Makefile       |    2 +-
 arch/arm/mach-at91/pm_slowclock.S |  281 -------------------------------------
 arch/arm/mach-at91/pm_suspend.S   |  281 +++++++++++++++++++++++++++++++++++++
 3 files changed, 282 insertions(+), 282 deletions(-)
 delete mode 100644 arch/arm/mach-at91/pm_slowclock.S
 create mode 100644 arch/arm/mach-at91/pm_suspend.S

diff --git a/arch/arm/mach-at91/Makefile b/arch/arm/mach-at91/Makefile
index 103c256..7df8c854 100644
--- a/arch/arm/mach-at91/Makefile
+++ b/arch/arm/mach-at91/Makefile
@@ -13,7 +13,7 @@ obj-$(CONFIG_SOC_SAMA5)		+= sama5.o
 
 # Power Management
 obj-$(CONFIG_PM)		+= pm.o
-obj-$(CONFIG_PM)		+= pm_slowclock.o
+obj-$(CONFIG_PM)		+= pm_suspend.o
 
 ifeq ($(CONFIG_PM_DEBUG),y)
 CFLAGS_pm.o += -DDEBUG
diff --git a/arch/arm/mach-at91/pm_slowclock.S b/arch/arm/mach-at91/pm_slowclock.S
deleted file mode 100644
index f56d114..0000000
--- a/arch/arm/mach-at91/pm_slowclock.S
+++ /dev/null
@@ -1,281 +0,0 @@
-/*
- * arch/arm/mach-at91/pm_slow_clock.S
- *
- *  Copyright (C) 2006 Savin Zlobec
- *
- * AT91SAM9 support:
- *  Copyright (C) 2007 Anti Sullin <anti.sullin@artecdesign.ee
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- */
-#include <linux/linkage.h>
-#include <linux/clk/at91_pmc.h>
-#include <mach/hardware.h>
-#include <mach/at91_ramc.h>
-
-#include "pm.h"
-
-pmc	.req	r0
-sdramc	.req	r1
-ramc1	.req	r2
-memctrl	.req	r3
-tmp1	.req	r4
-tmp2	.req	r5
-mode	.req	r6
-
-/*
- * Wait until master clock is ready (after switching master clock source)
- */
-	.macro wait_mckrdy
-1:	ldr	tmp1, [pmc, #AT91_PMC_SR]
-	tst	tmp1, #AT91_PMC_MCKRDY
-	beq	1b
-	.endm
-
-/*
- * Wait until master oscillator has stabilized.
- */
-	.macro wait_moscrdy
-1:	ldr	tmp1, [pmc, #AT91_PMC_SR]
-	tst	tmp1, #AT91_PMC_MOSCS
-	beq	1b
-	.endm
-
-/*
- * Wait until PLLA has locked.
- */
-	.macro wait_pllalock
-1:	ldr	tmp1, [pmc, #AT91_PMC_SR]
-	tst	tmp1, #AT91_PMC_LOCKA
-	beq	1b
-	.endm
-
-	.text
-
-/* void at91_slow_clock(void __iomem *pmc, void __iomem *sdramc,
- *			void __iomem *ramc1, int memctrl)
- */
-ENTRY(at91_slow_clock)
-	/* Save registers on stack */
-	stmfd	sp!, {r4 - r12, lr}
-
-	/*
-	 * Register usage:
-	 *  R0 = Base address of AT91_PMC
-	 *  R1 = Base address of RAM Controller (SDRAM, DDRSDR, or AT91_SYS)
-	 *  R2 = Base address of second RAM Controller or 0 if not present
-	 *  R3 = Memory controller
-	 *  R4 = temporary register
-	 *  R5 = temporary register
-	 */
-
-	/* Drain write buffer */
-	mov	tmp1, #0
-	mcr	p15, 0, tmp1, c7, c10, 4
-
-	mov	tmp1, memctrl
-	mov	tmp2, tmp1, lsr#AT91_PM_MODE_OFFSET
-	and	mode, tmp2, #AT91_PM_MODE_MASK
-
-	mov	tmp1, memctrl
-	and	memctrl, tmp1, #AT91_PM_MEMCTRL_MASK
-
-	cmp	memctrl, #AT91_MEMCTRL_MC
-	bne	ddr_sr_enable
-
-	/*
-	 * at91rm9200 Memory controller
-	 */
-	/* Put SDRAM in self-refresh mode */
-	mov	tmp1, #1
-	str	tmp1, [sdramc, #AT91RM9200_SDRAMC_SRR]
-	b	sdr_sr_done
-
-	/*
-	 * DDRSDR Memory controller
-	 */
-ddr_sr_enable:
-	cmp	memctrl, #AT91_MEMCTRL_DDRSDR
-	bne	sdr_sr_enable
-
-	/* LPDDR1 --> force DDR2 mode during self-refresh */
-	ldr	tmp1, [sdramc, #AT91_DDRSDRC_MDR]
-	str	tmp1, .saved_sam9_mdr
-	bic	tmp1, tmp1, #~AT91_DDRSDRC_MD
-	cmp	tmp1, #AT91_DDRSDRC_MD_LOW_POWER_DDR
-	ldreq	tmp1, [sdramc, #AT91_DDRSDRC_MDR]
-	biceq	tmp1, tmp1, #AT91_DDRSDRC_MD
-	orreq	tmp1, tmp1, #AT91_DDRSDRC_MD_DDR2
-	streq	tmp1, [sdramc, #AT91_DDRSDRC_MDR]
-
-	/* prepare for DDRAM self-refresh mode */
-	ldr	tmp1, [sdramc, #AT91_DDRSDRC_LPR]
-	str	tmp1, .saved_sam9_lpr
-	bic	tmp1, #AT91_DDRSDRC_LPCB
-	orr	tmp1, #AT91_DDRSDRC_LPCB_SELF_REFRESH
-
-	/* figure out if we use the second ram controller */
-	cmp	ramc1, #0
-	beq	ddr_no_2nd_ctrl
-
-	ldr	tmp2, [ramc1, #AT91_DDRSDRC_MDR]
-	str	tmp2, .saved_sam9_mdr1
-	bic	tmp2, tmp2, #~AT91_DDRSDRC_MD
-	cmp	tmp2, #AT91_DDRSDRC_MD_LOW_POWER_DDR
-	ldreq	tmp2, [ramc1, #AT91_DDRSDRC_MDR]
-	biceq	tmp2, tmp2, #AT91_DDRSDRC_MD
-	orreq	tmp2, tmp2, #AT91_DDRSDRC_MD_DDR2
-	streq	tmp2, [ramc1, #AT91_DDRSDRC_MDR]
-
-	ldr	tmp2, [ramc1, #AT91_DDRSDRC_LPR]
-	str	tmp2, .saved_sam9_lpr1
-	bic	tmp2, #AT91_DDRSDRC_LPCB
-	orr	tmp2, #AT91_DDRSDRC_LPCB_SELF_REFRESH
-
-	/* Enable DDRAM self-refresh mode */
-	str	tmp2, [ramc1, #AT91_DDRSDRC_LPR]
-ddr_no_2nd_ctrl:
-	str	tmp1, [sdramc, #AT91_DDRSDRC_LPR]
-
-	b	sdr_sr_done
-
-	/*
-	 * SDRAMC Memory controller
-	 */
-sdr_sr_enable:
-	/* Enable SDRAM self-refresh mode */
-	ldr	tmp1, [sdramc, #AT91_SDRAMC_LPR]
-	str	tmp1, .saved_sam9_lpr
-
-	bic	tmp1, #AT91_SDRAMC_LPCB
-	orr	tmp1, #AT91_SDRAMC_LPCB_SELF_REFRESH
-	str	tmp1, [sdramc, #AT91_SDRAMC_LPR]
-
-sdr_sr_done:
-	tst	mode, #AT91_PM_SLOW_CLOCK
-	beq	skip_disable_main_clock
-
-	/* Save Master clock setting */
-	ldr	tmp1, [pmc, #AT91_PMC_MCKR]
-	str	tmp1, .saved_mckr
-
-	/*
-	 * Set the Master clock source to slow clock
-	 */
-	bic	tmp1, tmp1, #AT91_PMC_CSS
-	str	tmp1, [pmc, #AT91_PMC_MCKR]
-
-	wait_mckrdy
-
-	/* Save PLLA setting and disable it */
-	ldr	tmp1, [pmc, #AT91_CKGR_PLLAR]
-	str	tmp1, .saved_pllar
-
-	mov	tmp1, #AT91_PMC_PLLCOUNT
-	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
-	str	tmp1, [pmc, #AT91_CKGR_MOR]
-
-skip_disable_main_clock:
-	/* Wait for interrupt */
-	mcr	p15, 0, tmp1, c7, c0, 4
-
-	tst	mode, #AT91_PM_SLOW_CLOCK
-	beq	skip_enable_main_clock
-
-	/* Turn on the main oscillator */
-	ldr	tmp1, [pmc, #AT91_CKGR_MOR]
-	orr	tmp1, tmp1, #AT91_PMC_MOSCEN
-	str	tmp1, [pmc, #AT91_CKGR_MOR]
-
-	wait_moscrdy
-
-	/* Restore PLLA setting */
-	ldr	tmp1, .saved_pllar
-	str	tmp1, [pmc, #AT91_CKGR_PLLAR]
-
-	tst	tmp1, #(AT91_PMC_MUL &  0xff0000)
-	bne	3f
-	tst	tmp1, #(AT91_PMC_MUL & ~0xff0000)
-	beq	4f
-3:
-	wait_pllalock
-4:
-
-	/*
-	 * Restore master clock setting
-	 */
-2:	ldr	tmp1, .saved_mckr
-	str	tmp1, [pmc, #AT91_PMC_MCKR]
-
-	wait_mckrdy
-
-skip_enable_main_clock:
-	/*
-	 * at91rm9200 Memory controller
-	 * Do nothing - self-refresh is automatically disabled.
-	 */
-	cmp	memctrl, #AT91_MEMCTRL_MC
-	beq	ram_restored
-
-	/*
-	 * DDRSDR Memory controller
-	 */
-	cmp	memctrl, #AT91_MEMCTRL_DDRSDR
-	bne	sdr_en_restore
-	/* Restore MDR in case of LPDDR1 */
-	ldr	tmp1, .saved_sam9_mdr
-	str	tmp1, [sdramc, #AT91_DDRSDRC_MDR]
-	/* Restore LPR on AT91 with DDRAM */
-	ldr	tmp1, .saved_sam9_lpr
-	str	tmp1, [sdramc, #AT91_DDRSDRC_LPR]
-
-	/* if we use the second ram controller */
-	cmp	ramc1, #0
-	ldrne	tmp2, .saved_sam9_mdr1
-	strne	tmp2, [ramc1, #AT91_DDRSDRC_MDR]
-	ldrne	tmp2, .saved_sam9_lpr1
-	strne	tmp2, [ramc1, #AT91_DDRSDRC_LPR]
-
-	b	ram_restored
-
-	/*
-	 * SDRAMC Memory controller
-	 */
-sdr_en_restore:
-	/* Restore LPR on AT91 with SDRAM */
-	ldr	tmp1, .saved_sam9_lpr
-	str	tmp1, [sdramc, #AT91_SDRAMC_LPR]
-
-ram_restored:
-	/* Restore registers, and return */
-	ldmfd	sp!, {r4 - r12, pc}
-
-
-.saved_mckr:
-	.word 0
-
-.saved_pllar:
-	.word 0
-
-.saved_sam9_lpr:
-	.word 0
-
-.saved_sam9_lpr1:
-	.word 0
-
-.saved_sam9_mdr:
-	.word 0
-
-.saved_sam9_mdr1:
-	.word 0
-
-ENTRY(at91_slow_clock_sz)
-	.word .-at91_slow_clock
diff --git a/arch/arm/mach-at91/pm_suspend.S b/arch/arm/mach-at91/pm_suspend.S
new file mode 100644
index 0000000..8edbad0
--- /dev/null
+++ b/arch/arm/mach-at91/pm_suspend.S
@@ -0,0 +1,281 @@
+/*
+ * arch/arm/mach-at91/pm_suspend.S
+ *
+ *  Copyright (C) 2006 Savin Zlobec
+ *
+ * AT91SAM9 support:
+ *  Copyright (C) 2007 Anti Sullin <anti.sullin@artecdesign.ee
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+#include <linux/linkage.h>
+#include <linux/clk/at91_pmc.h>
+#include <mach/hardware.h>
+#include <mach/at91_ramc.h>
+
+#include "pm.h"
+
+pmc	.req	r0
+sdramc	.req	r1
+ramc1	.req	r2
+memctrl	.req	r3
+tmp1	.req	r4
+tmp2	.req	r5
+mode	.req	r6
+
+/*
+ * Wait until master clock is ready (after switching master clock source)
+ */
+	.macro wait_mckrdy
+1:	ldr	tmp1, [pmc, #AT91_PMC_SR]
+	tst	tmp1, #AT91_PMC_MCKRDY
+	beq	1b
+	.endm
+
+/*
+ * Wait until master oscillator has stabilized.
+ */
+	.macro wait_moscrdy
+1:	ldr	tmp1, [pmc, #AT91_PMC_SR]
+	tst	tmp1, #AT91_PMC_MOSCS
+	beq	1b
+	.endm
+
+/*
+ * Wait until PLLA has locked.
+ */
+	.macro wait_pllalock
+1:	ldr	tmp1, [pmc, #AT91_PMC_SR]
+	tst	tmp1, #AT91_PMC_LOCKA
+	beq	1b
+	.endm
+
+	.text
+
+/* void at91_slow_clock(void __iomem *pmc, void __iomem *sdramc,
+ *			void __iomem *ramc1, int memctrl)
+ */
+ENTRY(at91_slow_clock)
+	/* Save registers on stack */
+	stmfd	sp!, {r4 - r12, lr}
+
+	/*
+	 * Register usage:
+	 *  R0 = Base address of AT91_PMC
+	 *  R1 = Base address of RAM Controller (SDRAM, DDRSDR, or AT91_SYS)
+	 *  R2 = Base address of second RAM Controller or 0 if not present
+	 *  R3 = Memory controller
+	 *  R4 = temporary register
+	 *  R5 = temporary register
+	 */
+
+	/* Drain write buffer */
+	mov	tmp1, #0
+	mcr	p15, 0, tmp1, c7, c10, 4
+
+	mov	tmp1, memctrl
+	mov	tmp2, tmp1, lsr#AT91_PM_MODE_OFFSET
+	and	mode, tmp2, #AT91_PM_MODE_MASK
+
+	mov	tmp1, memctrl
+	and	memctrl, tmp1, #AT91_PM_MEMCTRL_MASK
+
+	cmp	memctrl, #AT91_MEMCTRL_MC
+	bne	ddr_sr_enable
+
+	/*
+	 * at91rm9200 Memory controller
+	 */
+	/* Put SDRAM in self-refresh mode */
+	mov	tmp1, #1
+	str	tmp1, [sdramc, #AT91RM9200_SDRAMC_SRR]
+	b	sdr_sr_done
+
+	/*
+	 * DDRSDR Memory controller
+	 */
+ddr_sr_enable:
+	cmp	memctrl, #AT91_MEMCTRL_DDRSDR
+	bne	sdr_sr_enable
+
+	/* LPDDR1 --> force DDR2 mode during self-refresh */
+	ldr	tmp1, [sdramc, #AT91_DDRSDRC_MDR]
+	str	tmp1, .saved_sam9_mdr
+	bic	tmp1, tmp1, #~AT91_DDRSDRC_MD
+	cmp	tmp1, #AT91_DDRSDRC_MD_LOW_POWER_DDR
+	ldreq	tmp1, [sdramc, #AT91_DDRSDRC_MDR]
+	biceq	tmp1, tmp1, #AT91_DDRSDRC_MD
+	orreq	tmp1, tmp1, #AT91_DDRSDRC_MD_DDR2
+	streq	tmp1, [sdramc, #AT91_DDRSDRC_MDR]
+
+	/* prepare for DDRAM self-refresh mode */
+	ldr	tmp1, [sdramc, #AT91_DDRSDRC_LPR]
+	str	tmp1, .saved_sam9_lpr
+	bic	tmp1, #AT91_DDRSDRC_LPCB
+	orr	tmp1, #AT91_DDRSDRC_LPCB_SELF_REFRESH
+
+	/* figure out if we use the second ram controller */
+	cmp	ramc1, #0
+	beq	ddr_no_2nd_ctrl
+
+	ldr	tmp2, [ramc1, #AT91_DDRSDRC_MDR]
+	str	tmp2, .saved_sam9_mdr1
+	bic	tmp2, tmp2, #~AT91_DDRSDRC_MD
+	cmp	tmp2, #AT91_DDRSDRC_MD_LOW_POWER_DDR
+	ldreq	tmp2, [ramc1, #AT91_DDRSDRC_MDR]
+	biceq	tmp2, tmp2, #AT91_DDRSDRC_MD
+	orreq	tmp2, tmp2, #AT91_DDRSDRC_MD_DDR2
+	streq	tmp2, [ramc1, #AT91_DDRSDRC_MDR]
+
+	ldr	tmp2, [ramc1, #AT91_DDRSDRC_LPR]
+	str	tmp2, .saved_sam9_lpr1
+	bic	tmp2, #AT91_DDRSDRC_LPCB
+	orr	tmp2, #AT91_DDRSDRC_LPCB_SELF_REFRESH
+
+	/* Enable DDRAM self-refresh mode */
+	str	tmp2, [ramc1, #AT91_DDRSDRC_LPR]
+ddr_no_2nd_ctrl:
+	str	tmp1, [sdramc, #AT91_DDRSDRC_LPR]
+
+	b	sdr_sr_done
+
+	/*
+	 * SDRAMC Memory controller
+	 */
+sdr_sr_enable:
+	/* Enable SDRAM self-refresh mode */
+	ldr	tmp1, [sdramc, #AT91_SDRAMC_LPR]
+	str	tmp1, .saved_sam9_lpr
+
+	bic	tmp1, #AT91_SDRAMC_LPCB
+	orr	tmp1, #AT91_SDRAMC_LPCB_SELF_REFRESH
+	str	tmp1, [sdramc, #AT91_SDRAMC_LPR]
+
+sdr_sr_done:
+	tst	mode, #AT91_PM_SLOW_CLOCK
+	beq	skip_disable_main_clock
+
+	/* Save Master clock setting */
+	ldr	tmp1, [pmc, #AT91_PMC_MCKR]
+	str	tmp1, .saved_mckr
+
+	/*
+	 * Set the Master clock source to slow clock
+	 */
+	bic	tmp1, tmp1, #AT91_PMC_CSS
+	str	tmp1, [pmc, #AT91_PMC_MCKR]
+
+	wait_mckrdy
+
+	/* Save PLLA setting and disable it */
+	ldr	tmp1, [pmc, #AT91_CKGR_PLLAR]
+	str	tmp1, .saved_pllar
+
+	mov	tmp1, #AT91_PMC_PLLCOUNT
+	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
+	str	tmp1, [pmc, #AT91_CKGR_MOR]
+
+skip_disable_main_clock:
+	/* Wait for interrupt */
+	mcr	p15, 0, tmp1, c7, c0, 4
+
+	tst	mode, #AT91_PM_SLOW_CLOCK
+	beq	skip_enable_main_clock
+
+	/* Turn on the main oscillator */
+	ldr	tmp1, [pmc, #AT91_CKGR_MOR]
+	orr	tmp1, tmp1, #AT91_PMC_MOSCEN
+	str	tmp1, [pmc, #AT91_CKGR_MOR]
+
+	wait_moscrdy
+
+	/* Restore PLLA setting */
+	ldr	tmp1, .saved_pllar
+	str	tmp1, [pmc, #AT91_CKGR_PLLAR]
+
+	tst	tmp1, #(AT91_PMC_MUL &  0xff0000)
+	bne	3f
+	tst	tmp1, #(AT91_PMC_MUL & ~0xff0000)
+	beq	4f
+3:
+	wait_pllalock
+4:
+
+	/*
+	 * Restore master clock setting
+	 */
+2:	ldr	tmp1, .saved_mckr
+	str	tmp1, [pmc, #AT91_PMC_MCKR]
+
+	wait_mckrdy
+
+skip_enable_main_clock:
+	/*
+	 * at91rm9200 Memory controller
+	 * Do nothing - self-refresh is automatically disabled.
+	 */
+	cmp	memctrl, #AT91_MEMCTRL_MC
+	beq	ram_restored
+
+	/*
+	 * DDRSDR Memory controller
+	 */
+	cmp	memctrl, #AT91_MEMCTRL_DDRSDR
+	bne	sdr_en_restore
+	/* Restore MDR in case of LPDDR1 */
+	ldr	tmp1, .saved_sam9_mdr
+	str	tmp1, [sdramc, #AT91_DDRSDRC_MDR]
+	/* Restore LPR on AT91 with DDRAM */
+	ldr	tmp1, .saved_sam9_lpr
+	str	tmp1, [sdramc, #AT91_DDRSDRC_LPR]
+
+	/* if we use the second ram controller */
+	cmp	ramc1, #0
+	ldrne	tmp2, .saved_sam9_mdr1
+	strne	tmp2, [ramc1, #AT91_DDRSDRC_MDR]
+	ldrne	tmp2, .saved_sam9_lpr1
+	strne	tmp2, [ramc1, #AT91_DDRSDRC_LPR]
+
+	b	ram_restored
+
+	/*
+	 * SDRAMC Memory controller
+	 */
+sdr_en_restore:
+	/* Restore LPR on AT91 with SDRAM */
+	ldr	tmp1, .saved_sam9_lpr
+	str	tmp1, [sdramc, #AT91_SDRAMC_LPR]
+
+ram_restored:
+	/* Restore registers, and return */
+	ldmfd	sp!, {r4 - r12, pc}
+
+
+.saved_mckr:
+	.word 0
+
+.saved_pllar:
+	.word 0
+
+.saved_sam9_lpr:
+	.word 0
+
+.saved_sam9_lpr1:
+	.word 0
+
+.saved_sam9_mdr:
+	.word 0
+
+.saved_sam9_mdr1:
+	.word 0
+
+ENTRY(at91_slow_clock_sz)
+	.word .-at91_slow_clock
-- 
1.7.9.5

[PATCH v5 10/13] pm: at91: rename function name: at91_slow_clock()-->at91_pm_suspend_sram_fn

[Wenyou Yang]

As the file name's renaming, rename the file name at91_slow_clock()-->
at91_pm_suspend_sram_fn, rename the function handler's name at the same time.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
---
 arch/arm/mach-at91/pm.c         |   25 +++++++++++++------------
 arch/arm/mach-at91/pm_suspend.S |   24 ++++++++++--------------
 2 files changed, 23 insertions(+), 26 deletions(-)

diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c
index c3a697f..ce15013 100644
--- a/arch/arm/mach-at91/pm.c
+++ b/arch/arm/mach-at91/pm.c
@@ -131,13 +131,12 @@ int at91_suspend_entering_slow_clock(void)
 }
 EXPORT_SYMBOL(at91_suspend_entering_slow_clock);
 
-
-static void (*slow_clock)(void __iomem *pmc, void __iomem *ramc0,
+static void (*at91_suspend_sram_fn)(void __iomem *pmc, void __iomem *ramc0,
 			  void __iomem *ramc1, int memctrl);
 
-extern void at91_slow_clock(void __iomem *pmc, void __iomem *ramc0,
+extern void at91_pm_suspend_in_sram(void __iomem *pmc, void __iomem *ramc0,
 			    void __iomem *ramc1, int memctrl);
-extern u32 at91_slow_clock_sz;
+extern u32 at91_pm_suspend_in_sram_sz;
 
 static void at91_pm_suspend(suspend_state_t state)
 {
@@ -146,8 +145,8 @@ static void at91_pm_suspend(suspend_state_t state)
 	pm_data |= (state == PM_SUSPEND_MEM) ?
 				AT91_PM_MODE(AT91_PM_SLOW_CLOCK) : 0;
 
-	slow_clock(at91_pmc_base, at91_ramc_base[0],
-			at91_ramc_base[1], pm_data);
+	at91_suspend_sram_fn(at91_pmc_base, at91_ramc_base[0],
+				at91_ramc_base[1], pm_data);
 }
 
 static int at91_pm_enter(suspend_state_t state)
@@ -288,17 +287,19 @@ static void __init at91_pm_sram_init(void)
 		goto put_node;
 	}
 
-	sram_base = gen_pool_alloc(sram_pool, at91_slow_clock_sz);
+	sram_base = gen_pool_alloc(sram_pool, at91_pm_suspend_in_sram_sz);
 	if (!sram_base) {
-		pr_warn("%s: unable to alloc ocram!\n", __func__);
+		pr_warn("%s: unable to alloc sram!\n", __func__);
 		goto put_node;
 	}
 
 	sram_pbase = gen_pool_virt_to_phys(sram_pool, sram_base);
-	slow_clock = __arm_ioremap_exec(sram_pbase, at91_slow_clock_sz, false);
+	at91_suspend_sram_fn = __arm_ioremap_exec(sram_pbase,
+					at91_pm_suspend_in_sram_sz, false);
 
-	/* Copy the slow_clock handler to SRAM */
-	memcpy(slow_clock, at91_slow_clock, at91_slow_clock_sz);
+	/* Copy the pm suspend handler to SRAM */
+	memcpy(at91_suspend_sram_fn,
+		at91_pm_suspend_in_sram, at91_pm_suspend_in_sram_sz);
 
 put_node:
 	of_node_put(node);
@@ -311,7 +312,7 @@ static void __init at91_pm_init(void)
 	if (at91_cpuidle_device.dev.platform_data)
 		platform_device_register(&at91_cpuidle_device);
 
-	if (slow_clock)
+	if (at91_suspend_sram_fn)
 		suspend_set_ops(&at91_pm_ops);
 	else
 		pr_info("AT91: PM : Not supported, due to no sram allocated\n");
diff --git a/arch/arm/mach-at91/pm_suspend.S b/arch/arm/mach-at91/pm_suspend.S
index 8edbad0..122a3f1 100644
--- a/arch/arm/mach-at91/pm_suspend.S
+++ b/arch/arm/mach-at91/pm_suspend.S
@@ -55,23 +55,19 @@ mode	.req	r6
 
 	.text
 
-/* void at91_slow_clock(void __iomem *pmc, void __iomem *sdramc,
+/*
+ * void at91_pm_suspend_in_sram(void __iomem *pmc, void __iomem *sdramc,
  *			void __iomem *ramc1, int memctrl)
+ * @input param:
+ * 	@r0: the base address of AT91_PMC
+ *  	@r1: the base address of SDRAM Controller (SDRAM, DDRSDR, or AT91_SYS)
+ *	@r2: the base address of second SDRAM Controller or 0 if not present
+ *	@r3: the pm information
  */
-ENTRY(at91_slow_clock)
+ENTRY(at91_pm_suspend_in_sram)
 	/* Save registers on stack */
 	stmfd	sp!, {r4 - r12, lr}
 
-	/*
-	 * Register usage:
-	 *  R0 = Base address of AT91_PMC
-	 *  R1 = Base address of RAM Controller (SDRAM, DDRSDR, or AT91_SYS)
-	 *  R2 = Base address of second RAM Controller or 0 if not present
-	 *  R3 = Memory controller
-	 *  R4 = temporary register
-	 *  R5 = temporary register
-	 */
-
 	/* Drain write buffer */
 	mov	tmp1, #0
 	mcr	p15, 0, tmp1, c7, c10, 4
@@ -277,5 +273,5 @@ ram_restored:
 .saved_sam9_mdr1:
 	.word 0
 
-ENTRY(at91_slow_clock_sz)
-	.word .-at91_slow_clock
+ENTRY(at91_pm_suspend_in_sram_sz)
+	.word .-at91_pm_suspend_in_sram
-- 
1.7.9.5

[PATCH v5 11/13] pm: at91: remove the at91_xxx_standby() function definitions in the pm.h

[Wenyou Yang]

Because the the suspend to standby mode uses the sram function,
these functions will not used, remove the redundant code.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
---
 arch/arm/mach-at91/pm.h |   97 -----------------------------------------------
 1 file changed, 97 deletions(-)

diff --git a/arch/arm/mach-at91/pm.h b/arch/arm/mach-at91/pm.h
index 5bc9c33..158575e 100644
--- a/arch/arm/mach-at91/pm.h
+++ b/arch/arm/mach-at91/pm.h
@@ -12,7 +12,6 @@
 #define __ARCH_ARM_MACH_AT91_PM
 
 #include <asm/proc-fns.h>
-
 #include <mach/at91_ramc.h>
 
 #define	AT91_PM_MEMCTRL_MASK	0x0f
@@ -22,100 +21,4 @@
 
 #define	AT91_PM_SLOW_CLOCK	0x01
 
-#ifdef CONFIG_PM
-extern void at91_pm_set_standby(void (*at91_standby)(void));
-#else
-static inline void at91_pm_set_standby(void (*at91_standby)(void)) { }
-#endif
-
-/*
- * The AT91RM9200 goes into self-refresh mode with this command, and will
- * terminate self-refresh automatically on the next SDRAM access.
- *
- * Self-refresh mode is exited as soon as a memory access is made, but we don't
- * know for sure when that happens. However, we need to restore the low-power
- * mode if it was enabled before going idle. Restoring low-power mode while
- * still in self-refresh is "not recommended", but seems to work.
- */
-
-static inline void at91rm9200_standby(void)
-{
-	u32 lpr = at91_ramc_read(0, AT91RM9200_SDRAMC_LPR);
-
-	asm volatile(
-		"b    1f\n\t"
-		".align    5\n\t"
-		"1:  mcr    p15, 0, %0, c7, c10, 4\n\t"
-		"    str    %0, [%1, %2]\n\t"
-		"    str    %3, [%1, %4]\n\t"
-		"    mcr    p15, 0, %0, c7, c0, 4\n\t"
-		"    str    %5, [%1, %2]"
-		:
-		: "r" (0), "r" (AT91_BASE_SYS), "r" (AT91RM9200_SDRAMC_LPR),
-		  "r" (1), "r" (AT91RM9200_SDRAMC_SRR),
-		  "r" (lpr));
-}
-
-/* We manage both DDRAM/SDRAM controllers, we need more than one value to
- * remember.
- */
-static inline void at91_ddr_standby(void)
-{
-	/* Those two values allow us to delay self-refresh activation
-	 * to the maximum. */
-	u32 lpr0, lpr1 = 0;
-	u32 saved_lpr0, saved_lpr1 = 0;
-
-	if (at91_ramc_base[1]) {
-		saved_lpr1 = at91_ramc_read(1, AT91_DDRSDRC_LPR);
-		lpr1 = saved_lpr1 & ~AT91_DDRSDRC_LPCB;
-		lpr1 |= AT91_DDRSDRC_LPCB_SELF_REFRESH;
-	}
-
-	saved_lpr0 = at91_ramc_read(0, AT91_DDRSDRC_LPR);
-	lpr0 = saved_lpr0 & ~AT91_DDRSDRC_LPCB;
-	lpr0 |= AT91_DDRSDRC_LPCB_SELF_REFRESH;
-
-	/* self-refresh mode now */
-	at91_ramc_write(0, AT91_DDRSDRC_LPR, lpr0);
-	if (at91_ramc_base[1])
-		at91_ramc_write(1, AT91_DDRSDRC_LPR, lpr1);
-
-	cpu_do_idle();
-
-	at91_ramc_write(0, AT91_DDRSDRC_LPR, saved_lpr0);
-	if (at91_ramc_base[1])
-		at91_ramc_write(1, AT91_DDRSDRC_LPR, saved_lpr1);
-}
-
-/* We manage both DDRAM/SDRAM controllers, we need more than one value to
- * remember.
- */
-static inline void at91sam9_sdram_standby(void)
-{
-	u32 lpr0, lpr1 = 0;
-	u32 saved_lpr0, saved_lpr1 = 0;
-
-	if (at91_ramc_base[1]) {
-		saved_lpr1 = at91_ramc_read(1, AT91_SDRAMC_LPR);
-		lpr1 = saved_lpr1 & ~AT91_SDRAMC_LPCB;
-		lpr1 |= AT91_SDRAMC_LPCB_SELF_REFRESH;
-	}
-
-	saved_lpr0 = at91_ramc_read(0, AT91_SDRAMC_LPR);
-	lpr0 = saved_lpr0 & ~AT91_SDRAMC_LPCB;
-	lpr0 |= AT91_SDRAMC_LPCB_SELF_REFRESH;
-
-	/* self-refresh mode now */
-	at91_ramc_write(0, AT91_SDRAMC_LPR, lpr0);
-	if (at91_ramc_base[1])
-		at91_ramc_write(1, AT91_SDRAMC_LPR, lpr1);
-
-	cpu_do_idle();
-
-	at91_ramc_write(0, AT91_SDRAMC_LPR, saved_lpr0);
-	if (at91_ramc_base[1])
-		at91_ramc_write(1, AT91_SDRAMC_LPR, saved_lpr1);
-}
-
 #endif
-- 
1.7.9.5

[PATCH v5 12/13] pm: at91: remove the data member at91_xxx_standby() of struct ramc_ids

[Wenyou Yang]

Because the at91_xxx_standby() function is removed,
remove the data member of struct ramc_ids.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
---
 arch/arm/mach-at91/pm.c |   19 ++++---------------
 1 file changed, 4 insertions(+), 15 deletions(-)

diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c
index ce15013..f915f4b 100644
--- a/arch/arm/mach-at91/pm.c
+++ b/arch/arm/mach-at91/pm.c
@@ -225,10 +225,10 @@ void at91_pm_set_standby(void (*at91_standby)(void))
 }
 
 static struct of_device_id ramc_ids[] = {
-	{ .compatible = "atmel,at91rm9200-sdramc", .data = at91rm9200_standby },
-	{ .compatible = "atmel,at91sam9260-sdramc", .data = at91sam9_sdram_standby },
-	{ .compatible = "atmel,at91sam9g45-ddramc", .data = at91_ddr_standby },
-	{ .compatible = "atmel,sama5d3-ddramc", .data = at91_ddr_standby },
+	{ .compatible = "atmel,at91rm9200-sdramc" },
+	{ .compatible = "atmel,at91sam9260-sdramc" },
+	{ .compatible = "atmel,at91sam9g45-ddramc" },
+	{ .compatible = "atmel,sama5d3-ddramc" },
 	{ /*sentinel*/ }
 };
 
@@ -237,28 +237,17 @@ static void at91_dt_ramc(void)
 	struct device_node *np;
 	const struct of_device_id *of_id;
 	int idx = 0;
-	const void *standby = NULL;
 
 	for_each_matching_node_and_match(np, ramc_ids, &of_id) {
 		at91_ramc_base[idx] = of_iomap(np, 0);
 		if (!at91_ramc_base[idx])
 			panic(pr_fmt("unable to map ramc[%d] cpu registers\n"), idx);
 
-		if (!standby)
-			standby = of_id->data;
-
 		idx++;
 	}
 
 	if (!idx)
 		panic(pr_fmt("unable to find compatible ram controller node in dtb\n"));
-
-	if (!standby) {
-		pr_warn("ramc no standby function available\n");
-		return;
-	}
-
-	at91_pm_set_standby(standby);
 }
 
 static void __init at91_pm_sram_init(void)
-- 
1.7.9.5

[PATCH v5 13/13] pm: at91: amend the pm_suspend entry for at91_cpuidle_device

[Wenyou Yang]

Because the at91_xxx_standby() function is substitued by the at91_pm_suspend(),
the pm_suspend entry for at91_cpuidle_device changes as well.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
---
 arch/arm/mach-at91/pm.c |   16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c
index f915f4b..657b9ba 100644
--- a/arch/arm/mach-at91/pm.c
+++ b/arch/arm/mach-at91/pm.c
@@ -41,7 +41,6 @@ static struct {
 	int memctrl;
 } at91_pm_data;
 
-static void (*at91_pm_standby)(void);
 void __iomem *at91_ramc_base[2];
 
 static int at91_pm_valid_state(suspend_state_t state)
@@ -216,12 +215,15 @@ static struct platform_device at91_cpuidle_device = {
 	.name = "cpuidle-at91",
 };
 
-void at91_pm_set_standby(void (*at91_standby)(void))
+static void at91_cpuidle_set_suspend(void (*at91_suspend)(void))
 {
-	if (at91_standby) {
-		at91_cpuidle_device.dev.platform_data = at91_standby;
-		at91_pm_standby = at91_standby;
-	}
+	if (at91_suspend)
+		at91_cpuidle_device.dev.platform_data = at91_suspend;
+}
+
+static void at91_cpuidle_suspend(void)
+{
+	at91_pm_suspend(PM_SUSPEND_STANDBY);
 }
 
 static struct of_device_id ramc_ids[] = {
@@ -298,6 +300,8 @@ static void __init at91_pm_init(void)
 {
 	at91_pm_sram_init();
 
+	at91_cpuidle_set_suspend(at91_cpuidle_suspend);
+
 	if (at91_cpuidle_device.dev.platform_data)
 		platform_device_register(&at91_cpuidle_device);
 
-- 
1.7.9.5

Re: [PATCH v5 00/13] AT91 pm cleanup for 3.20

[Nicolas Ferre]

Le 29/01/2015 07:35, Wenyou Yang a écrit :
> Hi Nicolas,
> 
> This version is rebased on the branch: at91-3.20-cleanup of the repository
> 	git://git.kernel.org/pub/scm/linux/kernel/git/nferre/linux-at91.git
> 
> It is purpose to clean up the PM code, includes the patches from Peter Rosin and Sylvain Rochet.
> 
> Since verifying the USB clock and USB PLL disabling before suspending to memory,
> it aslo depends on the following patch serials from Sylvain:
> 	[PATCHv6 0/5] USB: gadget: atmel_usba_udc: Driver improvements
> 	[PATCHv7 0/6] USB: host: Atmel OHCI and EHCI drivers improvements
> 
> Removes CONFIG_AT91_SLOW_CLOCK config item to simply the PM config,
> The suspend to standby mode uses the same sram function as the suspend to memory mode.
> Remove some unused code.
> 
> Alexandr & Sylvain, Thank you very much for so many feedbacks.

Wenyou,

I'm sorry but the PM "cleanup" and "improvement" series won't be merged
for 3.20 (so you can remove this from the series subject). The series
are pretty big, address a sensitive aspect of the chips and are not
completely ready. So I propose to slow down the pace of versions and
focus on these two objectives:

1/ try to extract a handful of patches that could be sent as "fixes" for
3.20 (no more than 5-6 patches). If they are enough urgent, I can try to
add them to an early "fixes" branch during the 3.20 stabilization process.

2/ try to figure out if from this big amount of assembly code can't be
extracted some parts that can be converted to C or parts that can use
ARM common code (for cache management for instance).

During 3.21 development phase, we will come back to the "cleanup" series
and prepare something that can host the sama5 PM support. Finally we
will add sama5d3/sama5d4 PM enhancements.


> Changes in v5:
>  - Rebase the branch: at91-3.20-cleanup HEAD:fa9df37
> 
> Changes in v4:
>  - Clear unused state argument in at91_pm_verify_clocks()
>  - Remove pr_info("AT91:... slow_clock ? ..") in patch 07/13.
> 
> Changes in v3
>  - Sylvain splits the patch in two
>  - Add handling if no sram allocated for PM
>  - Retain the STANDBY and SUSPEND_MEM select in at91_pm_enter.
> 
> Changes in v2:
>  - Rebase on the at91-3.20-cleanup branch
>  - Recover the verify clock condition, only for suspend to memory.
>  - Collect ACK from Alexandre
>  - Add the macro for PM mode
> 
> Peter Rosin (1):
>   pm: at91: Workaround DDRSDRC self-refresh bug with LPDDR1 memories.
> 
> Sylvain Rochet (2):
>   pm: at91: pm_slowclock: fix suspend/resume hang up in timeouts
>   pm: at91: pm_slowclock: remove clocks which are already stopped when
>     entering slow clock mode
> 
> Wenyou Yang (10):
>   pm: at91: pm_slowclock: remove the unused code related with
>     SLOWDOWN_MASTER_CLOCK
>   pm: at91: move the copying the sram function to the sram
>     initializationi phase
>   ARM: at91: move select SRAM to ARCH_AT91
>   pm: at91: remove the config item CONFIG_AT91_SLOW_CLOCK
>   pm: at91: the standby mode uses the same sram function as the suspend
>     to memory mode
>   pm: at91: rename file name: pm_slowclock.S -->pm_suspend.S
>   pm: at91: rename function name:
>     at91_slow_clock()-->at91_pm_suspend_sram_fn
>   pm: at91: remove the at91_xxx_standby() function definitions in the
>     pm.h
>   pm: at91: remove the data member at91_xxx_standby() of struct
>     ramc_ids
>   pm: at91: amend the pm_suspend entry for at91_cpuidle_device
> 
>  arch/arm/mach-at91/Kconfig         |   17 +-
>  arch/arm/mach-at91/Makefile        |    2 +-
>  arch/arm/mach-at91/pm.c            |  166 +++++++++---------
>  arch/arm/mach-at91/pm.h            |  100 +----------
>  arch/arm/mach-at91/pm_slowclock.S  |  323 ------------------------------------
>  arch/arm/mach-at91/pm_suspend.S    |  277 +++++++++++++++++++++++++++++++
>  include/soc/at91/at91sam9_ddrsdr.h |    2 +-
>  7 files changed, 366 insertions(+), 521 deletions(-)
>  delete mode 100644 arch/arm/mach-at91/pm_slowclock.S
>  create mode 100644 arch/arm/mach-at91/pm_suspend.S
> 


-- 
Nicolas Ferre

RE: [PATCH v5 00/13] AT91 pm cleanup for 3.20

[Yang, Wenyou]

Hi Nicolas,

> -----Original Message-----
> From: Ferre, Nicolas
> Sent: Thursday, January 29, 2015 9:09 PM
> To: Yang, Wenyou; linux@arm.linux.org.uk
> Cc: linux-arm-kernel@lists.infradead.org; linux-kernel@vger.kernel.org;
> alexandre.belloni@free-electrons.com; sylvain.rochet@finsecur.com;
> peda@axentia.se; sergei.shtylyov@cogentembedded.com; linux@maxim.org.za
> Subject: Re: [PATCH v5 00/13] AT91 pm cleanup for 3.20
> 
> Le 29/01/2015 07:35, Wenyou Yang a écrit :
> > Hi Nicolas,
> >
> > This version is rebased on the branch: at91-3.20-cleanup of the repository
> > 	git://git.kernel.org/pub/scm/linux/kernel/git/nferre/linux-at91.git
> >
> > It is purpose to clean up the PM code, includes the patches from Peter Rosin
> and Sylvain Rochet.
> >
> > Since verifying the USB clock and USB PLL disabling before suspending
> > to memory, it aslo depends on the following patch serials from Sylvain:
> > 	[PATCHv6 0/5] USB: gadget: atmel_usba_udc: Driver improvements
> > 	[PATCHv7 0/6] USB: host: Atmel OHCI and EHCI drivers improvements
> >
> > Removes CONFIG_AT91_SLOW_CLOCK config item to simply the PM config,
> > The suspend to standby mode uses the same sram function as the suspend to
> memory mode.
> > Remove some unused code.
> >
> > Alexandr & Sylvain, Thank you very much for so many feedbacks.
> 
> Wenyou,
> 
> I'm sorry but the PM "cleanup" and "improvement" series won't be merged for 3.20
> (so you can remove this from the series subject). The series are pretty big,
> address a sensitive aspect of the chips and are not completely ready. So I
> propose to slow down the pace of versions and focus on these two objectives:
> 
> 1/ try to extract a handful of patches that could be sent as "fixes" for
> 3.20 (no more than 5-6 patches). If they are enough urgent, I can try to add them to
> an early "fixes" branch during the 3.20 stabilization process.
OK, I will send some stable patches.

> 
> 2/ try to figure out if from this big amount of assembly code can't be extracted
> some parts that can be converted to C or parts that can use ARM common code
> (for cache management for instance).
Yes, I need dig deeply the cache code.

> 
> During 3.21 development phase, we will come back to the "cleanup" series and
> prepare something that can host the sama5 PM support. Finally we will add
> sama5d3/sama5d4 PM enhancements.
> 
> 
> > Changes in v5:
> >  - Rebase the branch: at91-3.20-cleanup HEAD:fa9df37
> >
> > Changes in v4:
> >  - Clear unused state argument in at91_pm_verify_clocks()
> >  - Remove pr_info("AT91:... slow_clock ? ..") in patch 07/13.
> >
> > Changes in v3
> >  - Sylvain splits the patch in two
> >  - Add handling if no sram allocated for PM
> >  - Retain the STANDBY and SUSPEND_MEM select in at91_pm_enter.
> >
> > Changes in v2:
> >  - Rebase on the at91-3.20-cleanup branch
> >  - Recover the verify clock condition, only for suspend to memory.
> >  - Collect ACK from Alexandre
> >  - Add the macro for PM mode
> >
> > Peter Rosin (1):
> >   pm: at91: Workaround DDRSDRC self-refresh bug with LPDDR1 memories.
> >
> > Sylvain Rochet (2):
> >   pm: at91: pm_slowclock: fix suspend/resume hang up in timeouts
> >   pm: at91: pm_slowclock: remove clocks which are already stopped when
> >     entering slow clock mode
> >
> > Wenyou Yang (10):
> >   pm: at91: pm_slowclock: remove the unused code related with
> >     SLOWDOWN_MASTER_CLOCK
> >   pm: at91: move the copying the sram function to the sram
> >     initializationi phase
> >   ARM: at91: move select SRAM to ARCH_AT91
> >   pm: at91: remove the config item CONFIG_AT91_SLOW_CLOCK
> >   pm: at91: the standby mode uses the same sram function as the suspend
> >     to memory mode
> >   pm: at91: rename file name: pm_slowclock.S -->pm_suspend.S
> >   pm: at91: rename function name:
> >     at91_slow_clock()-->at91_pm_suspend_sram_fn
> >   pm: at91: remove the at91_xxx_standby() function definitions in the
> >     pm.h
> >   pm: at91: remove the data member at91_xxx_standby() of struct
> >     ramc_ids
> >   pm: at91: amend the pm_suspend entry for at91_cpuidle_device
> >
> >  arch/arm/mach-at91/Kconfig         |   17 +-
> >  arch/arm/mach-at91/Makefile        |    2 +-
> >  arch/arm/mach-at91/pm.c            |  166 +++++++++---------
> >  arch/arm/mach-at91/pm.h            |  100 +----------
> >  arch/arm/mach-at91/pm_slowclock.S  |  323 ------------------------------------
> >  arch/arm/mach-at91/pm_suspend.S    |  277
> +++++++++++++++++++++++++++++++
> >  include/soc/at91/at91sam9_ddrsdr.h |    2 +-
> >  7 files changed, 366 insertions(+), 521 deletions(-)  delete mode
> > 100644 arch/arm/mach-at91/pm_slowclock.S  create mode 100644
> > arch/arm/mach-at91/pm_suspend.S
> >
> 
> 
> --
> Nicolas Ferre

Best Regards,
Wenyou Yang

Re: [PATCH v5 00/13] AT91 pm cleanup for 3.20

[Alexandre Belloni]

(Adding Russ and Dave in Cc)

Hi Nicolas,

On 29/01/2015 at 14:08:51 +0100, Nicolas Ferre wrote :
> 2/ try to figure out if from this big amount of assembly code can't be
> extracted some parts that can be converted to C or parts that can use
> ARM common code (for cache management for instance).
> 

To avoid using so much asm, the plan would be to revive that series from
Russ:
http://lists.infradead.org/pipermail/linux-arm-kernel/2013-September/198778.html

It will also allow to avoid the __arm_ioremap_exec in pm.c

Russ, do you know what was missing to get it included? I could only find
that series submitted recently:
https://lkml.org/lkml/2014/11/26/575


-- 
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com