diff mbox series

[2/2] soc: bcm: add PM driver for Broadcom's PMB

Message ID 20201211215942.5726-3-zajec5@gmail.com
State New
Headers show
Series Broadcom's PMB (Power Management Bus) support | expand

Commit Message

Rafał Miłecki Dec. 11, 2020, 9:59 p.m. UTC
From: Rafał Miłecki <rafal@milecki.pl>

PMB can be found on BCM4908 and many other chipsets (e.g. BCM63138).
It's needed to power on and off SoC blocks like PCIe, SATA, USB.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
---
 drivers/soc/bcm/Kconfig   |   8 +
 drivers/soc/bcm/Makefile  |   1 +
 drivers/soc/bcm/bcm-pmb.c | 335 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 344 insertions(+)
 create mode 100644 drivers/soc/bcm/bcm-pmb.c

Comments

Rafał Miłecki Dec. 11, 2020, 10:02 p.m. UTC | #1
On 11.12.2020 22:59, Rafał Miłecki wrote:
> @@ -13,6 +13,14 @@ config BCM2835_POWER
>   	  firmware means that Linux usage of the same power domain
>   	  must be accessed using the RASPBERRYPI_POWER driver
>   
> +config BCM_PMB
> +	bool "Broadcom PMB (Power Management Bus) driver"
> +	depends on ARCH_BCM4908 || (COMPILE_TEST && OF)
> +	default ARCH_BCM4908
> +	select PM_GENERIC_DOMAINS if PM
> +	help
> +	  Foo

I'll improve description a bit in V2 ;)
Florian Fainelli Dec. 12, 2020, 3:26 a.m. UTC | #2
On 12/11/2020 1:59 PM, Rafał Miłecki wrote:
> From: Rafał Miłecki <rafal@milecki.pl>

> 

> PMB can be found on BCM4908 and many other chipsets (e.g. BCM63138).

> It's needed to power on and off SoC blocks like PCIe, SATA, USB.

> 

> Signed-off-by: Rafał Miłecki <rafal@milecki.pl>


This looks good to me, just a few nipicks below.

[snip]

> +static int bcm_pmb_probe(struct platform_device *pdev)

> +{

> +	struct device *dev = &pdev->dev;

> +	const struct bcm_pmb_pd_data *table;

> +	const struct bcm_pmb_pd_data *e;

> +	struct resource *res;

> +	struct bcm_pmb *pmb;

> +	int max_id;

> +	int err;

> +

> +	dev_info(dev, "START\n");


Stray debugging.

[snip]

> +

> +static const struct bcm_pmb_pd_data bcm_pmb_bcm4908_data[] = {

> +	{ .name = "pcie2", .id = BCM_PMB_PCIE2, .bus = 0, .device = 2, },

> +	{ .name = "pcie0", .id = BCM_PMB_PCIE0, .bus = 1, .device = 14, },

> +	{ .name = "pcie1", .id = BCM_PMB_PCIE1, .bus = 1, .device = 15, },

> +	{ .name = "usb", .id = BCM_PMB_HOST_USB, .bus = 1, .device = 17, },


Do you have to be more specific and spell out whether this is the host
controller (xhci) or device (bdc)? If not, then this looks good to me.
-- 
Florian
Rafał Miłecki Dec. 14, 2020, 8 a.m. UTC | #3
On 12.12.2020 04:26, Florian Fainelli wrote:
>> +

>> +static const struct bcm_pmb_pd_data bcm_pmb_bcm4908_data[] = {

>> +	{ .name = "pcie2", .id = BCM_PMB_PCIE2, .bus = 0, .device = 2, },

>> +	{ .name = "pcie0", .id = BCM_PMB_PCIE0, .bus = 1, .device = 14, },

>> +	{ .name = "pcie1", .id = BCM_PMB_PCIE1, .bus = 1, .device = 15, },

>> +	{ .name = "usb", .id = BCM_PMB_HOST_USB, .bus = 1, .device = 17, },

> 

> Do you have to be more specific and spell out whether this is the host

> controller (xhci) or device (bdc)? If not, then this looks good to me.


I believe I have to and I believe I already do. I used BCM_PMB_HOST_USB
which clearly (I believe) points to the HOST controller.

In 6838 part of pmc_drv.h from Broadcom's SDK I found:

enum {
     USB30_2X_Zone_Common,
     USB30_2X_Zone_USB_Host,
     USB30_2X_Zone_USB_Device,
};

and that's what makes me believe we need to specify HOST explicitly.
Rafał Miłecki Dec. 14, 2020, 12:24 p.m. UTC | #4
On 11.12.2020 23:08, Florian Fainelli wrote:
> On 12/11/20 1:59 PM, Rafał Miłecki wrote:

>> From: Rafał Miłecki <rafal@milecki.pl>

>>

>> PMB can be found on BCM4908 and many other chipsets (e.g. BCM63138).

>> It's needed to power on and off SoC blocks like PCIe, SATA, USB.

>>

>> Signed-off-by: Rafał Miłecki <rafal@milecki.pl>

> 

> I will do a more thorough review tonight, however do you mind moving the

> driver under drives/soc/bcm/bcm63xx? The first SoC that had PMB was

> 63138 and that one is DSL.


I now realized that bcm63xx's:
* Kconfig is wrapper in: if SOC_BCM63XX
* Makefile is conditional: obj-$(CONFIG_SOC_BCM63XX)

So it means I've to either:
1. Refactor bcm63xx structure
2. Make SOC_BCM63XX selectable on ARCH_BCM4908 and select it

I'm not sure if any of above is a really good idea. Any further thought, ideas?
Florian Fainelli Dec. 14, 2020, 5:32 p.m. UTC | #5
On 12/14/20 4:24 AM, Rafał Miłecki wrote:
> On 11.12.2020 23:08, Florian Fainelli wrote:

>> On 12/11/20 1:59 PM, Rafał Miłecki wrote:

>>> From: Rafał Miłecki <rafal@milecki.pl>

>>>

>>> PMB can be found on BCM4908 and many other chipsets (e.g. BCM63138).

>>> It's needed to power on and off SoC blocks like PCIe, SATA, USB.

>>>

>>> Signed-off-by: Rafał Miłecki <rafal@milecki.pl>

>>

>> I will do a more thorough review tonight, however do you mind moving the

>> driver under drives/soc/bcm/bcm63xx? The first SoC that had PMB was

>> 63138 and that one is DSL.

> 

> I now realized that bcm63xx's:

> * Kconfig is wrapper in: if SOC_BCM63XX

> * Makefile is conditional: obj-$(CONFIG_SOC_BCM63XX)

> 

> So it means I've to either:

> 1. Refactor bcm63xx structure

> 2. Make SOC_BCM63XX selectable on ARCH_BCM4908 and select it

> 

> I'm not sure if any of above is a really good idea. Any further thought,

> ideas?


Well, I was thinking about thing along those lines below, it's really
about putting drivers that belong to the same SoC family in the same
basket for easier maintenance while submitting patches/pull requests
from my side.

diff --git a/drivers/soc/bcm/Makefile b/drivers/soc/bcm/Makefile
index 7bc90e0bd773..0f0efa28d92b 100644
--- a/drivers/soc/bcm/Makefile
+++ b/drivers/soc/bcm/Makefile
@@ -1,5 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0-only
 obj-$(CONFIG_BCM2835_POWER)    += bcm2835-power.o
 obj-$(CONFIG_RASPBERRYPI_POWER)        += raspberrypi-power.o
-obj-$(CONFIG_SOC_BCM63XX)      += bcm63xx/
+obj-y                          += bcm63xx/
 obj-$(CONFIG_SOC_BRCMSTB)      += brcmstb/
diff --git a/drivers/soc/bcm/bcm63xx/Kconfig
b/drivers/soc/bcm/bcm63xx/Kconfig
index 16f648a6c70a..76fb61e7377e 100644
--- a/drivers/soc/bcm/bcm63xx/Kconfig
+++ b/drivers/soc/bcm/bcm63xx/Kconfig
@@ -10,3 +10,8 @@ config BCM63XX_POWER
          BCM6318, BCM6328, BCM6362 and BCM63268 SoCs.

 endif # SOC_BCM63XX
+
+config BCM_PMB_POWER
+       tristate "Broadcom PMB bus power domain driver"
+       depends on BMIPS_GENERIC || ARCH_BCM4908 || COMPILE_TEST
+       default ARCH_BCM4908



-- 
Florian
Rafał Miłecki Dec. 14, 2020, 5:34 p.m. UTC | #6
On 14.12.2020 18:32, Florian Fainelli wrote:
> On 12/14/20 4:24 AM, Rafał Miłecki wrote:

>> On 11.12.2020 23:08, Florian Fainelli wrote:

>>> On 12/11/20 1:59 PM, Rafał Miłecki wrote:

>>>> From: Rafał Miłecki <rafal@milecki.pl>

>>>>

>>>> PMB can be found on BCM4908 and many other chipsets (e.g. BCM63138).

>>>> It's needed to power on and off SoC blocks like PCIe, SATA, USB.

>>>>

>>>> Signed-off-by: Rafał Miłecki <rafal@milecki.pl>

>>>

>>> I will do a more thorough review tonight, however do you mind moving the

>>> driver under drives/soc/bcm/bcm63xx? The first SoC that had PMB was

>>> 63138 and that one is DSL.

>>

>> I now realized that bcm63xx's:

>> * Kconfig is wrapper in: if SOC_BCM63XX

>> * Makefile is conditional: obj-$(CONFIG_SOC_BCM63XX)

>>

>> So it means I've to either:

>> 1. Refactor bcm63xx structure

>> 2. Make SOC_BCM63XX selectable on ARCH_BCM4908 and select it

>>

>> I'm not sure if any of above is a really good idea. Any further thought,

>> ideas?

> 

> Well, I was thinking about thing along those lines below, it's really

> about putting drivers that belong to the same SoC family in the same

> basket for easier maintenance while submitting patches/pull requests

> from my side.

> 

> diff --git a/drivers/soc/bcm/Makefile b/drivers/soc/bcm/Makefile

> index 7bc90e0bd773..0f0efa28d92b 100644

> --- a/drivers/soc/bcm/Makefile

> +++ b/drivers/soc/bcm/Makefile

> @@ -1,5 +1,5 @@

>   # SPDX-License-Identifier: GPL-2.0-only

>   obj-$(CONFIG_BCM2835_POWER)    += bcm2835-power.o

>   obj-$(CONFIG_RASPBERRYPI_POWER)        += raspberrypi-power.o

> -obj-$(CONFIG_SOC_BCM63XX)      += bcm63xx/

> +obj-y                          += bcm63xx/

>   obj-$(CONFIG_SOC_BRCMSTB)      += brcmstb/

> diff --git a/drivers/soc/bcm/bcm63xx/Kconfig

> b/drivers/soc/bcm/bcm63xx/Kconfig

> index 16f648a6c70a..76fb61e7377e 100644

> --- a/drivers/soc/bcm/bcm63xx/Kconfig

> +++ b/drivers/soc/bcm/bcm63xx/Kconfig

> @@ -10,3 +10,8 @@ config BCM63XX_POWER

>            BCM6318, BCM6328, BCM6362 and BCM63268 SoCs.

> 

>   endif # SOC_BCM63XX

> +

> +config BCM_PMB_POWER

> +       tristate "Broadcom PMB bus power domain driver"

> +       depends on BMIPS_GENERIC || ARCH_BCM4908 || COMPILE_TEST

> +       default ARCH_BCM4908


Sounds OK to me, thanks for clarifying what approach you're OK with!
diff mbox series

Patch

diff --git a/drivers/soc/bcm/Kconfig b/drivers/soc/bcm/Kconfig
index 24f92a6e882a..327cfbd88471 100644
--- a/drivers/soc/bcm/Kconfig
+++ b/drivers/soc/bcm/Kconfig
@@ -13,6 +13,14 @@  config BCM2835_POWER
 	  firmware means that Linux usage of the same power domain
 	  must be accessed using the RASPBERRYPI_POWER driver
 
+config BCM_PMB
+	bool "Broadcom PMB (Power Management Bus) driver"
+	depends on ARCH_BCM4908 || (COMPILE_TEST && OF)
+	default ARCH_BCM4908
+	select PM_GENERIC_DOMAINS if PM
+	help
+	  Foo
+
 config RASPBERRYPI_POWER
 	bool "Raspberry Pi power domain driver"
 	depends on ARCH_BCM2835 || (COMPILE_TEST && OF)
diff --git a/drivers/soc/bcm/Makefile b/drivers/soc/bcm/Makefile
index 7bc90e0bd773..c451ee76259f 100644
--- a/drivers/soc/bcm/Makefile
+++ b/drivers/soc/bcm/Makefile
@@ -1,5 +1,6 @@ 
 # SPDX-License-Identifier: GPL-2.0-only
 obj-$(CONFIG_BCM2835_POWER)	+= bcm2835-power.o
+obj-$(CONFIG_BCM_PMB)		+= bcm-pmb.o
 obj-$(CONFIG_RASPBERRYPI_POWER)	+= raspberrypi-power.o
 obj-$(CONFIG_SOC_BCM63XX)	+= bcm63xx/
 obj-$(CONFIG_SOC_BRCMSTB)	+= brcmstb/
diff --git a/drivers/soc/bcm/bcm-pmb.c b/drivers/soc/bcm/bcm-pmb.c
new file mode 100644
index 000000000000..31820e56418d
--- /dev/null
+++ b/drivers/soc/bcm/bcm-pmb.c
@@ -0,0 +1,335 @@ 
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2013 Broadcom
+ * Copyright (C) 2020 Rafał Miłecki <rafal@milecki.pl>
+ */
+
+#include <dt-bindings/soc/bcm-pmb.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm_domain.h>
+#include <linux/reset/bcm63xx_pmb.h>
+
+#define BPCM_ID_REG					0x00
+#define BPCM_CAPABILITIES				0x04
+#define  BPCM_CAP_NUM_ZONES				0x000000ff
+#define  BPCM_CAP_SR_REG_BITS				0x0000ff00
+#define  BPCM_CAP_PLLTYPE				0x00030000
+#define  BPCM_CAP_UBUS					0x00080000
+#define BPCM_CONTROL					0x08
+#define BPCM_STATUS					0x0c
+#define BPCM_ROSC_CONTROL				0x10
+#define BPCM_ROSC_THRESH_H				0x14
+#define BPCM_ROSC_THRESHOLD_BCM6838			0x14
+#define BPCM_ROSC_THRESH_S				0x18
+#define BPCM_ROSC_COUNT_BCM6838				0x18
+#define BPCM_ROSC_COUNT					0x1c
+#define BPCM_PWD_CONTROL_BCM6838			0x1c
+#define BPCM_PWD_CONTROL				0x20
+#define BPCM_SR_CONTROL_BCM6838				0x20
+#define BPCM_PWD_ACCUM_CONTROL				0x24
+#define BPCM_SR_CONTROL					0x28
+#define BPCM_GLOBAL_CONTROL				0x2c
+#define BPCM_MISC_CONTROL				0x30
+#define BPCM_MISC_CONTROL2				0x34
+#define BPCM_SGPHY_CNTL					0x38
+#define BPCM_SGPHY_STATUS				0x3c
+#define BPCM_ZONE0					0x40
+#define  BPCM_ZONE_CONTROL				0x00
+#define   BPCM_ZONE_CONTROL_MANUAL_CLK_EN		0x00000001
+#define   BPCM_ZONE_CONTROL_MANUAL_RESET_CTL		0x00000002
+#define   BPCM_ZONE_CONTROL_FREQ_SCALE_USED		0x00000004	/* R/O */
+#define   BPCM_ZONE_CONTROL_DPG_CAPABLE			0x00000008	/* R/O */
+#define   BPCM_ZONE_CONTROL_MANUAL_MEM_PWR		0x00000030
+#define   BPCM_ZONE_CONTROL_MANUAL_ISO_CTL		0x00000040
+#define   BPCM_ZONE_CONTROL_MANUAL_CTL			0x00000080
+#define   BPCM_ZONE_CONTROL_DPG_CTL_EN			0x00000100
+#define   BPCM_ZONE_CONTROL_PWR_DN_REQ			0x00000200
+#define   BPCM_ZONE_CONTROL_PWR_UP_REQ			0x00000400
+#define   BPCM_ZONE_CONTROL_MEM_PWR_CTL_EN		0x00000800
+#define   BPCM_ZONE_CONTROL_BLK_RESET_ASSERT		0x00001000
+#define   BPCM_ZONE_CONTROL_MEM_STBY			0x00002000
+#define   BPCM_ZONE_CONTROL_RESERVED			0x0007c000
+#define   BPCM_ZONE_CONTROL_PWR_CNTL_STATE		0x00f80000
+#define   BPCM_ZONE_CONTROL_FREQ_SCALAR_DYN_SEL		0x01000000	/* R/O */
+#define   BPCM_ZONE_CONTROL_PWR_OFF_STATE		0x02000000	/* R/O */
+#define   BPCM_ZONE_CONTROL_PWR_ON_STATE		0x04000000	/* R/O */
+#define   BPCM_ZONE_CONTROL_PWR_GOOD			0x08000000	/* R/O */
+#define   BPCM_ZONE_CONTROL_DPG_PWR_STATE		0x10000000	/* R/O */
+#define   BPCM_ZONE_CONTROL_MEM_PWR_STATE		0x20000000	/* R/O */
+#define   BPCM_ZONE_CONTROL_ISO_STATE			0x40000000	/* R/O */
+#define   BPCM_ZONE_CONTROL_RESET_STATE			0x80000000	/* R/O */
+#define  BPCM_ZONE_CONFIG1				0x04
+#define  BPCM_ZONE_CONFIG2				0x08
+#define  BPCM_ZONE_FREQ_SCALAR_CONTROL			0x0c
+#define  BPCM_ZONE_SIZE					0x10
+
+struct bcm_pmb {
+	struct device *dev;
+	void __iomem *base;
+	spinlock_t lock;
+	bool little_endian;
+	struct genpd_onecell_data genpd_onecell_data;
+};
+
+struct bcm_pmb_pd_data {
+	const char * const name;
+	int id;
+	u8 bus;
+	u8 device;
+};
+
+struct bcm_pmb_pm_domain {
+	struct bcm_pmb *pmb;
+	const struct bcm_pmb_pd_data *data;
+	struct generic_pm_domain genpd;
+};
+
+static int bcm_pmb_bpcm_read(struct bcm_pmb *pmb, int bus, u8 device,
+			     int offset, u32 *val)
+{
+	void __iomem *base = pmb->base + bus * 0x20;
+	unsigned long flags;
+	int err;
+
+	spin_lock_irqsave(&pmb->lock, flags);
+	err = bpcm_rd(base, device, offset, val);
+	spin_unlock_irqrestore(&pmb->lock, flags);
+
+	if (!err)
+		*val = pmb->little_endian ? le32_to_cpu(*val) : be32_to_cpu(*val);
+
+	return err;
+}
+
+static int bcm_pmb_bpcm_write(struct bcm_pmb *pmb, int bus, u8 device,
+			      int offset, u32 val)
+{
+	void __iomem *base = pmb->base + bus * 0x20;
+	unsigned long flags;
+	int err;
+
+	val = pmb->little_endian ? cpu_to_le32(val) : cpu_to_be32(val);
+
+	spin_lock_irqsave(&pmb->lock, flags);
+	err = bpcm_wr(base, device, offset, val);
+	spin_unlock_irqrestore(&pmb->lock, flags);
+
+	return err;
+}
+
+static int bcm_pmb_power_off_zone(struct bcm_pmb *pmb, int bus, u8 device,
+				  int zone)
+{
+	int offset;
+	u32 val;
+	int err;
+
+	offset = BPCM_ZONE0 + zone * BPCM_ZONE_SIZE + BPCM_ZONE_CONTROL;
+
+	err = bcm_pmb_bpcm_read(pmb, bus, device, offset, &val);
+	if (err)
+		return err;
+
+	val |= BPCM_ZONE_CONTROL_PWR_DN_REQ;
+	val &= ~BPCM_ZONE_CONTROL_PWR_UP_REQ;
+
+	err = bcm_pmb_bpcm_write(pmb, bus, device, offset, val);
+
+	return err;
+}
+
+static int bcm_pmb_power_on_zone(struct bcm_pmb *pmb, int bus, u8 device,
+				 int zone)
+{
+	int offset;
+	u32 val;
+	int err;
+
+	offset = BPCM_ZONE0 + zone * BPCM_ZONE_SIZE + BPCM_ZONE_CONTROL;
+
+	err = bcm_pmb_bpcm_read(pmb, bus, device, offset, &val);
+	if (err)
+		return err;
+
+	if (!(val & BPCM_ZONE_CONTROL_PWR_ON_STATE)) {
+		val &= ~BPCM_ZONE_CONTROL_PWR_DN_REQ;
+		val |= BPCM_ZONE_CONTROL_DPG_CTL_EN;
+		val |= BPCM_ZONE_CONTROL_PWR_UP_REQ;
+		val |= BPCM_ZONE_CONTROL_MEM_PWR_CTL_EN;
+		val |= BPCM_ZONE_CONTROL_BLK_RESET_ASSERT;
+
+		err = bcm_pmb_bpcm_write(pmb, bus, device, offset, val);
+	}
+
+	return err;
+}
+
+static int bcm_pmb_power_off_device(struct bcm_pmb *pmb, int bus, u8 device)
+{
+	int offset;
+	u32 val;
+	int err;
+
+	/* Entire device can be powered off by powering off the 0th zone */
+	offset = BPCM_ZONE0 + BPCM_ZONE_CONTROL;
+
+	err = bcm_pmb_bpcm_read(pmb, bus, device, offset, &val);
+	if (err)
+		return err;
+
+	if (!(val & BPCM_ZONE_CONTROL_PWR_OFF_STATE)) {
+		val = BPCM_ZONE_CONTROL_PWR_DN_REQ;
+
+		err = bcm_pmb_bpcm_write(pmb, bus, device, offset, val);
+	}
+
+	return err;
+}
+
+static int bcm_pmb_power_on_device(struct bcm_pmb *pmb, int bus, u8 device)
+{
+	u32 val;
+	int err;
+	int i;
+
+	err = bcm_pmb_bpcm_read(pmb, bus, device, BPCM_CAPABILITIES, &val);
+	if (err)
+		return err;
+
+	for (i = 0; i < (val & BPCM_CAP_NUM_ZONES); i++) {
+		err = bcm_pmb_power_on_zone(pmb, bus, device, i);
+		if (err)
+			return err;
+	}
+
+	return err;
+}
+
+static int bcm_pmb_power_on(struct generic_pm_domain *genpd)
+{
+	struct bcm_pmb_pm_domain *pd = container_of(genpd, struct bcm_pmb_pm_domain, genpd);
+	const struct bcm_pmb_pd_data *data = pd->data;
+	struct bcm_pmb *pmb = pd->pmb;
+
+	switch (data->id) {
+	case BCM_PMB_PCIE0:
+	case BCM_PMB_PCIE1:
+	case BCM_PMB_PCIE2:
+		return bcm_pmb_power_on_zone(pmb, data->bus, data->device, 0);
+	case BCM_PMB_HOST_USB:
+		return bcm_pmb_power_on_device(pmb, data->bus, data->device);
+	default:
+		dev_err(pmb->dev, "unsupported device id: %d\n", data->id);
+		return -EINVAL;
+	}
+}
+
+static int bcm_pmb_power_off(struct generic_pm_domain *genpd)
+{
+	struct bcm_pmb_pm_domain *pd = container_of(genpd, struct bcm_pmb_pm_domain, genpd);
+	const struct bcm_pmb_pd_data *data = pd->data;
+	struct bcm_pmb *pmb = pd->pmb;
+
+	switch (data->id) {
+	case BCM_PMB_PCIE0:
+	case BCM_PMB_PCIE1:
+	case BCM_PMB_PCIE2:
+		return bcm_pmb_power_off_zone(pmb, data->bus, data->device, 0);
+	case BCM_PMB_HOST_USB:
+		return bcm_pmb_power_off_device(pmb, data->bus, data->device);
+	default:
+		dev_err(pmb->dev, "unsupported device id: %d\n", data->id);
+		return -EINVAL;
+	}
+}
+
+static int bcm_pmb_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	const struct bcm_pmb_pd_data *table;
+	const struct bcm_pmb_pd_data *e;
+	struct resource *res;
+	struct bcm_pmb *pmb;
+	int max_id;
+	int err;
+
+	dev_info(dev, "START\n");
+
+	pmb = devm_kzalloc(dev, sizeof(*pmb), GFP_KERNEL);
+	if (!pmb)
+		return -ENOMEM;
+
+	pmb->dev = dev;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	pmb->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(pmb->base))
+		return PTR_ERR(pmb->base);
+
+	spin_lock_init(&pmb->lock);
+
+	pmb->little_endian = !of_device_is_big_endian(dev->of_node);
+
+	table = of_device_get_match_data(dev);
+	if (!table)
+		return -EINVAL;
+
+	max_id = 0;
+	for (e = table; e->name; e++)
+		max_id = max(max_id, e->id);
+
+	pmb->genpd_onecell_data.num_domains = max_id + 1;
+	pmb->genpd_onecell_data.domains =
+		devm_kcalloc(dev, pmb->genpd_onecell_data.num_domains,
+			     sizeof(struct generic_pm_domain *), GFP_KERNEL);
+	if (!pmb->genpd_onecell_data.domains)
+		return -ENOMEM;
+
+	for (e = table; e->name; e++) {
+		struct bcm_pmb_pm_domain *pd = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
+
+		pd->pmb = pmb;
+		pd->data = e;
+		pd->genpd.name = e->name;
+		pd->genpd.power_on = bcm_pmb_power_on;
+		pd->genpd.power_off = bcm_pmb_power_off;
+
+		pm_genpd_init(&pd->genpd, NULL, true);
+		pmb->genpd_onecell_data.domains[e->id] = &pd->genpd;
+	}
+
+	err = of_genpd_add_provider_onecell(dev->of_node, &pmb->genpd_onecell_data);
+	if (err) {
+		dev_err(dev, "failed to add genpd provider: %d\n", err);
+		return err;
+	}
+
+	return 0;
+}
+
+static const struct bcm_pmb_pd_data bcm_pmb_bcm4908_data[] = {
+	{ .name = "pcie2", .id = BCM_PMB_PCIE2, .bus = 0, .device = 2, },
+	{ .name = "pcie0", .id = BCM_PMB_PCIE0, .bus = 1, .device = 14, },
+	{ .name = "pcie1", .id = BCM_PMB_PCIE1, .bus = 1, .device = 15, },
+	{ .name = "usb", .id = BCM_PMB_HOST_USB, .bus = 1, .device = 17, },
+	{ },
+};
+
+static const struct of_device_id bcm_pmb_of_match[] = {
+	{ .compatible = "brcm,bcm4908-pmb", .data = &bcm_pmb_bcm4908_data, },
+	{ },
+};
+
+static struct platform_driver bcm_pmb_driver = {
+	.driver = {
+		.name = "bcm-pmb",
+		.of_match_table = bcm_pmb_of_match,
+	},
+	.probe  = bcm_pmb_probe,
+};
+
+builtin_platform_driver(bcm_pmb_driver);