[PATCH v2 0/3] make power off work on iMX6S RIoTBoard

[Oleksij Rempel]

v2:
- remove "suspend to ram" from comment (copy/paste from linux comment)
- add "depends on ARCH_IMX6"
- remove unused defines

Oleksij Rempel (3):
ARM: riotboard: provide standby on power off option
ARM: i.MX: provide handler for power off over standby
regulator: pfuze: provide power over standby handler

arch/arm/dts/imx6s-riotboard.dts | 7 ++++
arch/arm/mach-imx/imx6.c | 49 +++++++++++++++++++++++++
arch/arm/mach-imx/include/mach/imx6.h | 1 +
drivers/regulator/Kconfig | 1 +
drivers/regulator/pfuze.c | 67 +++++++++++++++++++++++++++++++++++
5 files changed, 125 insertions(+)

[Oleksij Rempel]

One of the Freescale recommended sequences for power off with external
PMIC is the following:
...
3. SoC is programming PMIC for power off when standby is asserted.
4. In CCM STOP mode, Standby is asserted, PMIC gates SoC supplies.

See:
http://www.nxp.com/assets/documents/data/en/reference-manuals/IMX6DQRM.pdf
page 5083

This patch implements step 4. of this sequence.

Signed-off-by: Oleksij Rempel <***@pengutronix.de>
---
arch/arm/mach-imx/imx6.c | 49 +++++++++++++++++++++++++++++++++++
arch/arm/mach-imx/include/mach/imx6.h | 1 +
2 files changed, 50 insertions(+)

diff --git a/arch/arm/mach-imx/imx6.c b/arch/arm/mach-imx/imx6.c
index 5afbf6b30f..96c1f64093 100644
--- a/arch/arm/mach-imx/imx6.c
+++ b/arch/arm/mach-imx/imx6.c
@@ -25,6 +25,19 @@
#include <asm/mmu.h>
#include <asm/cache-l2x0.h>

+#include <poweroff.h>
+#include <mach/imx6-regs.h>
+#include <io.h>
+
+#define CLPCR 0x54
+#define BP_CLPCR_LPM(mode) ((mode) & 0x3)
+#define BM_CLPCR_LPM (0x3 << 0)
+#define BM_CLPCR_SBYOS (0x1 << 6)
+#define BM_CLPCR_VSTBY (0x1 << 8)
+#define BP_CLPCR_STBY_COUNT 9
+#define BM_CLPCR_COSC_PWRDOWN (0x1 << 11)
+#define BM_CLPCR_BYP_MMDC_CH1_LPM_HS (0x1 << 21)
+
void imx6_init_lowlevel(void)
{
void __iomem *aips1 = (void *)MX6_AIPS1_ON_BASE_ADDR;
@@ -296,3 +309,39 @@ static int imx6_fixup_cpus_register(void)
return of_register_fixup(imx6_fixup_cpus, NULL);
}
device_initcall(imx6_fixup_cpus_register);
+
+void __noreturn imx6_pm_stby_poweroff(void)
+{
+ void *ccm_base = IOMEM(MX6_CCM_BASE_ADDR);
+ void *gpc_base = IOMEM(MX6_GPC_BASE_ADDR);
+ u32 val;
+
+ /*
+ * All this is done to get the PMIC_STBY_REQ line high which will
+ * cause the PMIC to turn off the i.MX6.
+ */
+
+ /*
+ * First mask all interrupts in the GPC. This is necessary for
+ * unknown reasons
+ */
+ writel(0xffffffff, gpc_base + 0x8);
+ writel(0xffffffff, gpc_base + 0xc);
+ writel(0xffffffff, gpc_base + 0x10);
+ writel(0xffffffff, gpc_base + 0x14);
+
+ val = readl(ccm_base + CLPCR);
+
+ val &= ~BM_CLPCR_LPM;
+ val |= BP_CLPCR_LPM(2);
+ val |= 0x3 << BP_CLPCR_STBY_COUNT;
+ val |= BM_CLPCR_VSTBY;
+ val |= BM_CLPCR_SBYOS;
+ val |= BM_CLPCR_BYP_MMDC_CH1_LPM_HS;
+
+ writel(val, ccm_base + CLPCR);
+
+ asm("wfi");
+
+ while(1);
+}
diff --git a/arch/arm/mach-imx/include/mach/imx6.h b/arch/arm/mach-imx/include/mach/imx6.h
index 6ad53433cb..e4633ed5f2 100644
--- a/arch/arm/mach-imx/include/mach/imx6.h
+++ b/arch/arm/mach-imx/include/mach/imx6.h
@@ -7,6 +7,7 @@
#include <mach/revision.h>

void imx6_init_lowlevel(void);
+void __noreturn imx6_pm_stby_poweroff(void);

#define IMX6_ANATOP_SI_REV 0x260
#define IMX6SL_ANATOP_SI_REV 0x280

[Oleksij Rempel]

This patch is providing an optional power off handler
which will configure standby state of the PMIC to disable all power lines.

In my power consumption test on RIoTBoard, I got the following results:
power off without this patch: 320 mA
power off with this patch: 2 mA

Signed-off-by: Oleksij Rempel <***@pengutronix.de>
---
drivers/regulator/Kconfig | 1 +
drivers/regulator/pfuze.c | 67 +++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 68 insertions(+)

diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 6a6c6d2248..92db8dc0e0 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -19,5 +19,6 @@ config REGULATOR_BCM283X
config REGULATOR_PFUZE
bool "Freescale PFUZE100/200/3000 regulator driver"
depends on I2C
+ depends on ARCH_IMX6

endif
diff --git a/drivers/regulator/pfuze.c b/drivers/regulator/pfuze.c
index 2a5fb715ce..dc41e8f55b 100644
--- a/drivers/regulator/pfuze.c
+++ b/drivers/regulator/pfuze.c
@@ -26,10 +26,33 @@

#include <i2c/i2c.h>

+#include <poweroff.h>
+#include <mach/imx6.h>
+
#define DRIVERNAME "pfuze"

#define MC13XXX_NUMREGS 0x3f

+#define PFUZE100_SW1ABMODE 0x23
+#define PFUZE100_SW1CMODE 0x31
+#define PFUZE100_SW2MODE 0x38
+#define PFUZE100_SW3AMODE 0x3f
+#define PFUZE100_SW3BMODE 0x46
+#define PFUZE100_SW4MODE 0x4d
+#define PFUZE100_VGEN1VOL 0x6c
+#define PFUZE100_VGEN2VOL 0x6d
+#define PFUZE100_VGEN3VOL 0x6e
+#define PFUZE100_VGEN4VOL 0x6f
+#define PFUZE100_VGEN5VOL 0x70
+#define PFUZE100_VGEN6VOL 0x71
+
+#define PFUZE100_SWxMODE_MASK 0xf
+#define PFUZE100_SWxMODE_APS_APS 0x8
+#define PFUZE100_SWxMODE_APS_OFF 0x4
+
+#define PFUZE100_VGENxLPWR BIT(6)
+#define PFUZE100_VGENxSTBY BIT(5)
+
struct pfuze {
struct device_d *dev;
struct regmap *map;
@@ -85,6 +108,46 @@ static int pfuze_i2c_reg_write(void *ctx, unsigned int reg, unsigned int val)
return ret == 1 ? 0 : ret;
}

+static void pfuze_power_off_prepare(struct poweroff_handler *handler)
+{
+ dev_info(pfuze_dev->dev, "Configure standy mode for power off");
+
+ /* Switch from default mode: APS/APS to APS/Off */
+ regmap_write_bits(pfuze_dev->map, PFUZE100_SW1ABMODE,
+ PFUZE100_SWxMODE_MASK, PFUZE100_SWxMODE_APS_OFF);
+ regmap_write_bits(pfuze_dev->map, PFUZE100_SW1CMODE,
+ PFUZE100_SWxMODE_MASK, PFUZE100_SWxMODE_APS_OFF);
+ regmap_write_bits(pfuze_dev->map, PFUZE100_SW2MODE,
+ PFUZE100_SWxMODE_MASK, PFUZE100_SWxMODE_APS_OFF);
+ regmap_write_bits(pfuze_dev->map, PFUZE100_SW3AMODE,
+ PFUZE100_SWxMODE_MASK, PFUZE100_SWxMODE_APS_OFF);
+ regmap_write_bits(pfuze_dev->map, PFUZE100_SW3BMODE,
+ PFUZE100_SWxMODE_MASK, PFUZE100_SWxMODE_APS_OFF);
+ regmap_write_bits(pfuze_dev->map, PFUZE100_SW4MODE,
+ PFUZE100_SWxMODE_MASK, PFUZE100_SWxMODE_APS_OFF);
+
+ regmap_write_bits(pfuze_dev->map, PFUZE100_VGEN1VOL,
+ PFUZE100_VGENxLPWR | PFUZE100_VGENxSTBY,
+ PFUZE100_VGENxSTBY);
+ regmap_write_bits(pfuze_dev->map, PFUZE100_VGEN2VOL,
+ PFUZE100_VGENxLPWR | PFUZE100_VGENxSTBY,
+ PFUZE100_VGENxSTBY);
+ regmap_write_bits(pfuze_dev->map, PFUZE100_VGEN3VOL,
+ PFUZE100_VGENxLPWR | PFUZE100_VGENxSTBY,
+ PFUZE100_VGENxSTBY);
+ regmap_write_bits(pfuze_dev->map, PFUZE100_VGEN4VOL,
+ PFUZE100_VGENxLPWR | PFUZE100_VGENxSTBY,
+ PFUZE100_VGENxSTBY);
+ regmap_write_bits(pfuze_dev->map, PFUZE100_VGEN5VOL,
+ PFUZE100_VGENxLPWR | PFUZE100_VGENxSTBY,
+ PFUZE100_VGENxSTBY);
+ regmap_write_bits(pfuze_dev->map, PFUZE100_VGEN6VOL,
+ PFUZE100_VGENxLPWR | PFUZE100_VGENxSTBY,
+ PFUZE100_VGENxSTBY);
+
+ imx6_pm_stby_poweroff();
+}
+
static struct regmap_bus regmap_pfuze_i2c_bus = {
.reg_write = pfuze_i2c_reg_write,
.reg_read = pfuze_i2c_reg_read,
@@ -122,6 +185,10 @@ static int __init pfuze_probe(struct device_d *dev)
if (pfuze_init_callback)
pfuze_init_callback(pfuze_dev->map);

+ if (of_property_read_bool(dev->device_node,
+ "fsl,pmic-stby-poweroff"))
+ return poweroff_handler_register_fn(pfuze_power_off_prepare);
+
return 0;
}

[Oleksij Rempel]

This board, as well as some other boards with i.MX6 and a PMIC, uses a
"PMIC_STBY_REQ" line to notify the PMIC about a state change.
The PMIC is programmed for a specific state change before triggering the
line.
In this case, PMIC_STBY_REQ can be used for stand by, sleep
and power off modes.

Signed-off-by: Oleksij Rempel <***@pengutronix.de>
---
arch/arm/dts/imx6s-riotboard.dts | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/arch/arm/dts/imx6s-riotboard.dts b/arch/arm/dts/imx6s-riotboard.dts
index 575887267e..ddd0d5ba2d 100644
--- a/arch/arm/dts/imx6s-riotboard.dts
+++ b/arch/arm/dts/imx6s-riotboard.dts
@@ -42,3 +42,10 @@
barebox,provide-mac-address = <&fec 0x620>;
};

+&clks {
+ fsl,pmic-stby-poweroff;
+};
+
+&pmic {
+ fsl,pmic-stby-poweroff;
+};

[Lucas Stach]

Post by Oleksij Rempel
- remove "suspend to ram" from comment (copy/paste from linux comment)
- add "depends on ARCH_IMX6"
- remove unused defines
ARM: riotboard: provide standby on power off option
ARM: i.MX: provide handler for power off over standby
regulator: pfuze: provide power over standby handler
arch/arm/dts/imx6s-riotboard.dts | 7 ++++
arch/arm/mach-imx/imx6.c | 49 +++++++++++++++++++++++++
arch/arm/mach-imx/include/mach/imx6.h | 1 +
drivers/regulator/Kconfig | 1 +
drivers/regulator/pfuze.c | 67 +++++++++++++++++++++++++++++++++++
5 files changed, 125 insertions(+)

Applied, thanks.