diff mbox

[V5,1/2] irqchip: imx-gpcv2: IMX GPCv2 driver for wakeup sources

Message ID 1437150300-8134-2-git-send-email-shenwei.wang@freescale.com (mailing list archive)
State New, archived
Headers show

Commit Message

Shenwei Wang July 17, 2015, 4:24 p.m. UTC
IMX7D contains a new version of GPC IP block (GPCv2). It has two
major functions: power management and wakeup source management.
This patch adds a new irqchip driver to manage the interrupt wakeup
sources on IMX7D.
When the system is in WFI (wait for interrupt) mode, this GPC block
will be the first block on the platform to be activated and signaled.
Under normal wait mode during cpu idle, the system can be woke up
by any enabled interrupts. Under standby or suspend mode, the system
can only be woke up by the pre-defined wakeup sources.

Signed-off-by: Shenwei Wang <shenwei.wang@freescale.com>
---
 drivers/irqchip/Kconfig         |   7 +
 drivers/irqchip/Makefile        |   1 +
 drivers/irqchip/irq-imx-gpcv2.c | 311 ++++++++++++++++++++++++++++++++++++++++
 include/soc/imx/gpcv2.h         | 137 ++++++++++++++++++
 4 files changed, 456 insertions(+)
 create mode 100644 drivers/irqchip/irq-imx-gpcv2.c
 create mode 100644 include/soc/imx/gpcv2.h

Comments

Thomas Gleixner July 17, 2015, 9:49 p.m. UTC | #1
On Fri, 17 Jul 2015, Shenwei Wang wrote:
> +++ b/drivers/irqchip/irq-imx-gpcv2.c
> @@ -0,0 +1,311 @@
> +
> +/*
> + * Copyright (C) 2015 Freescale Semiconductor, Inc.
> + *
> + * 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/of_address.h>
> +#include <linux/of_irq.h>
> +#include <linux/slab.h>
> +#include <linux/syscore_ops.h>
> +#include "irqchip.h"

This file is deprecated. Use linux/irqchip.h instead.

> +static struct imx_irq_gpcv2 *gpcv2_get_chip_data(void)
> +{
> +	struct irq_data *data;
> +	int virq;
> +
> +	/* Since GPCv2 is the default IRQ domain, its private data can
> +	 * be gotten from any irq descriptor. Here we use interrupt #19
> +	 * which is for snvs-rtc.
> +	 */

Yuck. What kind of logic is that?

Use some random hardcoded number to find something which has been set
by this driver?

> +	virq = irq_find_mapping(0, 19);
> +
> +	for (data = irq_get_irq_data(virq); data;
> +	     data = data->parent_data) {
> +		if (!data->domain)
> +			continue;
> +
> +		if (!strcmp(data->domain->name, "GPCv2"))

So you are relying on internal knowledge of the irq domain code which
sets the domain name to the chip name if the domain name is not
initialized by other means.

Brilliant, NOT!

In other words you are interested in the irq chip associated with that
domain and not with the domain itself.

Care to explain what you are trying to do and why you think there are
no better ways to figure that out?

> +			return data->chip_data;
> +	}
> +
> +	return 0;

This wants to be 'return NULL;' if at all.

> +}
> +
> +static int gpcv2_wakeup_source_save(void)
> +{
> +	struct imx_irq_gpcv2 *cd;
> +	void __iomem *reg;
> +	int i;
> +
> +	cd = gpcv2_get_chip_data();
> +	if (!cd)
> +		return 0;
> +
> +	for (i = 0; i < IMR_NUM; i++) {

Why is IMR_NUM a hard coded constant and not provided by DT?

> +		reg = cd->gpc_base + cd->cpu2wakeup + i * 4;
> +		cd->enabled_irqs[i] = readl_relaxed(reg);
> +		writel_relaxed(cd->wakeup_sources[i], reg);
> +	}
> +
> +	pr_devel("%s ----\r\n", __func__);
> +	pr_devel("Enabled IRQ:\t %08X %08X %08X %08X\r\n",
> +			cd->enabled_irqs[0],
> +			cd->enabled_irqs[1],
> +			cd->enabled_irqs[2],
> +			cd->enabled_irqs[3]);
> +	pr_devel("Wakeup Sources:\t %08X %08X %08X %08X\r\n",
> +			cd->wakeup_sources[0],
> +			cd->wakeup_sources[1],
> +			cd->wakeup_sources[2],
> +			cd->wakeup_sources[3]);

Do we really need this debug stuff in mainline?

> +static int imx_gpcv2_irq_set_wake(struct irq_data *d, unsigned int on)
> +{
> +	unsigned int idx = d->hwirq / 32;
> +	struct imx_irq_gpcv2 *cd = d->chip_data;
> +	u32 mask, val;
> +	unsigned long flags;
> +	void __iomem *reg;

Can you come up with an even less readable way to arrange those
declarations?

> +	spin_lock_irqsave(&cd->lock, flags);

That wants to be a raw spinlock.

> +	reg = cd->gpc_base + cd->cpu2wakeup + idx * 4;

This lacks a comment explaining the magic math

> +static void imx_gpcv2_irq_unmask(struct irq_data *d)
> +{
> +	void __iomem *reg;
> +	struct imx_irq_gpcv2 *cd = d->chip_data;
> +	u32 val;
> +	unsigned long flags;

Another random variant of arranging declarations.

> +	spin_lock_irqsave(&cd->lock, flags);

This callback is always called with interrupts disabled, so this wants
to be raw_spin_lock()

> +	reg = cd->gpc_base + cd->cpu2wakeup + d->hwirq / 32 * 4;
> +	val = readl_relaxed(reg);
> +	val &= ~(1 << d->hwirq % 32);
> +	writel_relaxed(val, reg);
> +	irq_chip_unmask_parent(d);

Why needs this to be called under cd->lock?

If there is a requirement to do so, then it needs a comment.

> +	spin_unlock_irqrestore(&cd->lock, flags);

> +static int imx_gpcv2_domain_xlate(struct irq_domain *domain,
> +				struct device_node *controller,
> +				const u32 *intspec,
> +				unsigned int intsize,
> +				unsigned long *out_hwirq,
> +				unsigned int *out_type)
> +{
> +	if (domain->of_node != controller)
> +		return -EINVAL;	/* Shouldn't happen, really... */

Tail comments are horrible to read. Either your comment has a value
then put it above the if construct or just get rid of it.

> +static int __init imx_gpcv2_irqchip_init(struct device_node *node,
> +			       struct device_node *parent)
> +{
> +	struct irq_domain *parent_domain, *domain;
> +	int i, val;
> +	struct imx_irq_gpcv2 *cd;
> +
> +	if (!parent) {
> +		pr_err("%s: no parent, giving up\n", node->full_name);
> +		return -ENODEV;
> +	}
> +
> +	parent_domain = irq_find_host(parent);
> +	if (!parent_domain) {
> +		pr_err("%s: unable to obtain parent domain\n", node->full_name);
> +		return -ENXIO;
> +	}
> +
> +	cd = kzalloc(sizeof(struct imx_irq_gpcv2), GFP_KERNEL);
> +	BUG_ON(!cd);

This BUG_ON does not make any sense as you just return an error code
if something else goes wrong after that.

> +	cd->gpc_base = of_iomap(node, 0);
> +	if (!cd->gpc_base) {
> +		pr_err("fsl-gpcv2: unable to map gpc registers\n");
> +		kzfree(cd);

Surely this needs kzfree because cd contains security relevant data,
right?

> +	/*
> +	 * Due to hardware design requirement, need to make sure GPR

s/requirement/failure/ right?

> +	 * interrupt(#32) is unmasked during RUN mode to avoid entering
> +	 * DSM by mistake.
> +	 */
> +	writel_relaxed(~0x1, cd->gpc_base + cd->cpu2wakeup);

Magic constant '~0x1' ?

> +
> +	/* Mask the wakeup sources in M/F power domain */
> +	cd->mfmix_mask[0] = 0x54010000;
> +	cd->mfmix_mask[1] = 0xc00;
> +	cd->mfmix_mask[2] = 0x0;
> +	cd->mfmix_mask[3] = 0x400010;

Again, really intuitive and self explaining magic constants.

> +
> +IRQCHIP_DECLARE(imx_gpcv2, "fsl,imx7d-gpc", imx_gpcv2_irqchip_init);

I'm not a DT expert, but AFAIK there is a requirement to document the
bindings somewhere. -ENODOCUMENT!

> +
> +enum gpcv2_mode {
> +	WAIT_CLOCKED,		/* wfi only */

Again, tail comments are horrible to read. Use proper KernelDoc if you
want to document stuff. Though I doubt that any of these comments have
any value at all.

Aside of that these names are pretty generic and prone to create a
namespace clash sooner or later.

> +	WAIT_UNCLOCKED,		/* WAIT */
> +	WAIT_UNCLOCKED_POWER_OFF,	/* WAIT + SRPG */
> +	STOP_POWER_ON,		/* just STOP */
> +	STOP_POWER_OFF,		/* STOP + SRPG */
> +};
> +
> +enum gpcv2_slot {

What is this enum for?

> +	CORE0_A7,
> +	CORE1_A7,
> +	SCU_A7,
> +	FAST_MEGA_MIX,
> +	MIPI_PHY,
> +	PCIE_PHY,
> +	USB_OTG1_PHY,
> +	USB_OTG2_PHY,
> +	USB_HSIC_PHY,
> +	CORE0_M4,

Namespace?

> +};

> +struct imx_irq_gpcv2 {
> +	spinlock_t lock;

  raw_spinlock_t

> +	void __iomem *gpc_base;
> +	struct regmap *anatop;
> +	struct regmap *imx_src;
> +	u32 wakeup_sources[IMR_NUM];
> +	u32 enabled_irqs[IMR_NUM];
> +	u32 mfmix_mask[IMR_NUM];
> +	u32 wakeupmix_mask[IMR_NUM];
> +	u32 lpsrmix_mask[IMR_NUM];
> +	u32 cpu2wakeup;
> +	void (*lpm_env_setup)(struct imx_irq_gpcv2 *);
> +	void (*lpm_env_clean)(struct imx_irq_gpcv2 *);
> +	void (*lpm_cpu_power_gate)(struct imx_irq_gpcv2 *, u32, bool);
> +	void (*lpm_plat_power_gate)(struct imx_irq_gpcv2 *, bool);
> +	void (*set_mode)(struct imx_irq_gpcv2 *, enum gpcv2_mode mode);
> +	void (*standby)(struct imx_irq_gpcv2 *);
> +	void (*suspend)(struct imx_irq_gpcv2 *);
> +	void (*set_slot)(struct imx_irq_gpcv2 *cd, u32 index,
> +			enum gpcv2_slot m_core, bool mode, bool ack);
> +	void (*clear_slots)(struct imx_irq_gpcv2 *);
> +	void (*lpm_enable_core)(struct imx_irq_gpcv2 *,
> +			bool enable, u32 offset);
> +
> +
> +	void (*suspend_fn_in_ocram)(void __iomem *ocram_vbase);
> +	void __iomem *ocram_vbase;

How many of these struct members are actually relevant to this driver
and what is the purpose of those? A proper KernelDoc comment would
shed some light on it.

> +};
> +
> +void ca7_cpu_resume(void);
> +void imx7_suspend(void __iomem *ocram_vbase);

How is that related to the irqchip driver?

Thanks,

	tglx
Shenwei Wang July 21, 2015, 3:07 p.m. UTC | #2
Hi Thomas,

Thank you for the high-quality review. Please check my comments inline below.

> -----Original Message-----

> From: Thomas Gleixner [mailto:tglx@linutronix.de]

> Sent: 2015?7?17? 16:50

> To: Wang Shenwei-B38339

> Cc: shawn.guo@linaro.org; jason@lakedaemon.net;

> linux-arm-kernel@lists.infradead.org; linux-kernel@vger.kernel.org

> Subject: Re: [PATCH V5 1/2] irqchip: imx-gpcv2: IMX GPCv2 driver for wakeup

> sources

> 

> On Fri, 17 Jul 2015, Shenwei Wang wrote:

> > +++ b/drivers/irqchip/irq-imx-gpcv2.c

> > @@ -0,0 +1,311 @@

> > +

> > +/*

> > + * Copyright (C) 2015 Freescale Semiconductor, Inc.

> > + *

> > + * 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/of_address.h>

> > +#include <linux/of_irq.h>

> > +#include <linux/slab.h>

> > +#include <linux/syscore_ops.h>

> > +#include "irqchip.h"

> 

> This file is deprecated. Use linux/irqchip.h instead.

> 

Okay.

> > +static struct imx_irq_gpcv2 *gpcv2_get_chip_data(void) {

> > +	struct irq_data *data;

> > +	int virq;

> > +

> > +	/* Since GPCv2 is the default IRQ domain, its private data can

> > +	 * be gotten from any irq descriptor. Here we use interrupt #19

> > +	 * which is for snvs-rtc.

> > +	 */

> 

> Yuck. What kind of logic is that?

> 

> Use some random hardcoded number to find something which has been set by

> this driver?

> 

> > +	virq = irq_find_mapping(0, 19);

> > +

> > +	for (data = irq_get_irq_data(virq); data;

> > +	     data = data->parent_data) {

> > +		if (!data->domain)

> > +			continue;

> > +

> > +		if (!strcmp(data->domain->name, "GPCv2"))

> 

> So you are relying on internal knowledge of the irq domain code which sets the

> domain name to the chip name if the domain name is not initialized by other

> means.

> 

> Brilliant, NOT!

> 

> In other words you are interested in the irq chip associated with that domain and

> not with the domain itself.

> 

> Care to explain what you are trying to do and why you think there are no better

> ways to figure that out?

> 

When I wrote the driver, there were two options to let other modules like suspend 
and cpuidle drivers to access this instance of imx_irq_gpcv2:
Option #1 is to use the private data pointer of the irqdomain. 
Option #2 is to export a global variable here.
I selected option #1 because it could decouple this irq driver from those who may
use this instance. But option #2 is more direct and simple.
 
> > +			return data->chip_data;

> > +	}

> > +

> > +	return 0;

> 

> This wants to be 'return NULL;' if at all.

> 

Okay.

> > +}

> > +

> > +static int gpcv2_wakeup_source_save(void) {

> > +	struct imx_irq_gpcv2 *cd;

> > +	void __iomem *reg;

> > +	int i;

> > +

> > +	cd = gpcv2_get_chip_data();

> > +	if (!cd)

> > +		return 0;

> > +

> > +	for (i = 0; i < IMR_NUM; i++) {

> 

> Why is IMR_NUM a hard coded constant and not provided by DT?

> 

It can be provided by DT. However, as it is a fixed number and will never change once the 
Chip is produced I selected to hard code it.

> > +		reg = cd->gpc_base + cd->cpu2wakeup + i * 4;

> > +		cd->enabled_irqs[i] = readl_relaxed(reg);

> > +		writel_relaxed(cd->wakeup_sources[i], reg);

> > +	}

> > +

> > +	pr_devel("%s ----\r\n", __func__);

> > +	pr_devel("Enabled IRQ:\t %08X %08X %08X %08X\r\n",

> > +			cd->enabled_irqs[0],

> > +			cd->enabled_irqs[1],

> > +			cd->enabled_irqs[2],

> > +			cd->enabled_irqs[3]);

> > +	pr_devel("Wakeup Sources:\t %08X %08X %08X %08X\r\n",

> > +			cd->wakeup_sources[0],

> > +			cd->wakeup_sources[1],

> > +			cd->wakeup_sources[2],

> > +			cd->wakeup_sources[3]);

> 

> Do we really need this debug stuff in mainline?

> 

Ok to remove it.

> > +static int imx_gpcv2_irq_set_wake(struct irq_data *d, unsigned int

> > +on) {

> > +	unsigned int idx = d->hwirq / 32;

> > +	struct imx_irq_gpcv2 *cd = d->chip_data;

> > +	u32 mask, val;

> > +	unsigned long flags;

> > +	void __iomem *reg;

> 

> Can you come up with an even less readable way to arrange those declarations?

> 

Will change the declarations like following:
	u32 mask, val;
	unsigned long flags;
	void __iomem *reg;

	unsigned int idx = d->hwirq / 32;
	struct imx_irq_gpcv2 *cd = d->chip_data;

> > +	spin_lock_irqsave(&cd->lock, flags);

> 

> That wants to be a raw spinlock.

> 

Will change it to raw_spin_lock

> > +	reg = cd->gpc_base + cd->cpu2wakeup + idx * 4;

> 

> This lacks a comment explaining the magic math

> 

> > +static void imx_gpcv2_irq_unmask(struct irq_data *d) {

> > +	void __iomem *reg;

> > +	struct imx_irq_gpcv2 *cd = d->chip_data;

> > +	u32 val;

> > +	unsigned long flags;

> 

> Another random variant of arranging declarations.

> 

Will change it like following:
	u32 val;
	unsigned long flags;
    void __iomem *reg;
    struct imx_irq_gpcv2 *cd = d->chip_data;

>>+	spin_lock_irqsave(&cd->lock, flags);

> 

> This callback is always called with interrupts disabled, so this wants to be

> raw_spin_lock()

> 

Okay. 

> > +	reg = cd->gpc_base + cd->cpu2wakeup + d->hwirq / 32 * 4;

> > +	val = readl_relaxed(reg);

> > +	val &= ~(1 << d->hwirq % 32);

> > +	writel_relaxed(val, reg);

> > +	irq_chip_unmask_parent(d);

> 

> Why needs this to be called under cd->lock?

> 

You are right. Irq_chip_unmask_parent(d) should be moved under cd->lock.

> If there is a requirement to do so, then it needs a comment.

> 

> > +	spin_unlock_irqrestore(&cd->lock, flags);

> 

> > +static int imx_gpcv2_domain_xlate(struct irq_domain *domain,

> > +				struct device_node *controller,

> > +				const u32 *intspec,

> > +				unsigned int intsize,

> > +				unsigned long *out_hwirq,

> > +				unsigned int *out_type)

> > +{

> > +	if (domain->of_node != controller)

> > +		return -EINVAL;	/* Shouldn't happen, really... */

> 

> Tail comments are horrible to read. Either your comment has a value then put it

> above the if construct or just get rid of it.

> 

Will remove it.

> > +static int __init imx_gpcv2_irqchip_init(struct device_node *node,

> > +			       struct device_node *parent) {

> > +	struct irq_domain *parent_domain, *domain;

> > +	int i, val;

> > +	struct imx_irq_gpcv2 *cd;

> > +

> > +	if (!parent) {

> > +		pr_err("%s: no parent, giving up\n", node->full_name);

> > +		return -ENODEV;

> > +	}

> > +

> > +	parent_domain = irq_find_host(parent);

> > +	if (!parent_domain) {

> > +		pr_err("%s: unable to obtain parent domain\n", node->full_name);

> > +		return -ENXIO;

> > +	}

> > +

> > +	cd = kzalloc(sizeof(struct imx_irq_gpcv2), GFP_KERNEL);

> > +	BUG_ON(!cd);

> 

> This BUG_ON does not make any sense as you just return an error code if

> something else goes wrong after that.

> 

Make sense. Will remove it.

> > +	cd->gpc_base = of_iomap(node, 0);

> > +	if (!cd->gpc_base) {

> > +		pr_err("fsl-gpcv2: unable to map gpc registers\n");

> > +		kzfree(cd);

> 

> Surely this needs kzfree because cd contains security relevant data, right?

> 

It is not secure data. Will change it to kfree.

> > +	/*

> > +	 * Due to hardware design requirement, need to make sure GPR

> 

> s/requirement/failure/ right?

> 

Agree.

> > +	 * interrupt(#32) is unmasked during RUN mode to avoid entering

> > +	 * DSM by mistake.

> > +	 */

> > +	writel_relaxed(~0x1, cd->gpc_base + cd->cpu2wakeup);

> 

> Magic constant '~0x1' ?

> 

> > +

> > +	/* Mask the wakeup sources in M/F power domain */

> > +	cd->mfmix_mask[0] = 0x54010000;

> > +	cd->mfmix_mask[1] = 0xc00;

> > +	cd->mfmix_mask[2] = 0x0;

> > +	cd->mfmix_mask[3] = 0x400010;

> 

> Again, really intuitive and self explaining magic constants.

> 

> > +

> > +IRQCHIP_DECLARE(imx_gpcv2, "fsl,imx7d-gpc", imx_gpcv2_irqchip_init);

> 

> I'm not a DT expert, but AFAIK there is a requirement to document the bindings

> somewhere. -ENODOCUMENT!

> 

Will add this string in Documentation/devicetree/bindings/power/fsl,imx-gpc.txt

> > +

> > +enum gpcv2_mode {

> > +	WAIT_CLOCKED,		/* wfi only */

> 

> Again, tail comments are horrible to read. Use proper KernelDoc if you want to

> document stuff. Though I doubt that any of these comments have any value at all.

> 

> Aside of that these names are pretty generic and prone to create a namespace

> clash sooner or later.

> 

Will remove the tail comments.

> > +	WAIT_UNCLOCKED,		/* WAIT */

> > +	WAIT_UNCLOCKED_POWER_OFF,	/* WAIT + SRPG */

> > +	STOP_POWER_ON,		/* just STOP */

> > +	STOP_POWER_OFF,		/* STOP + SRPG */

> > +};

> > +

> > +enum gpcv2_slot {

> 

> What is this enum for?

> 

It defined all the power domains that are controlled by GPCv2 block.

> > +	CORE0_A7,

> > +	CORE1_A7,

> > +	SCU_A7,

> > +	FAST_MEGA_MIX,

> > +	MIPI_PHY,

> > +	PCIE_PHY,

> > +	USB_OTG1_PHY,

> > +	USB_OTG2_PHY,

> > +	USB_HSIC_PHY,

> > +	CORE0_M4,

> 

> Namespace?

> 

> > +};

> 

> > +struct imx_irq_gpcv2 {

> > +	spinlock_t lock;

> 

>   raw_spinlock_t

> 

> > +	void __iomem *gpc_base;

> > +	struct regmap *anatop;

> > +	struct regmap *imx_src;

> > +	u32 wakeup_sources[IMR_NUM];

> > +	u32 enabled_irqs[IMR_NUM];

> > +	u32 mfmix_mask[IMR_NUM];

> > +	u32 wakeupmix_mask[IMR_NUM];

> > +	u32 lpsrmix_mask[IMR_NUM];

> > +	u32 cpu2wakeup;

> > +	void (*lpm_env_setup)(struct imx_irq_gpcv2 *);

> > +	void (*lpm_env_clean)(struct imx_irq_gpcv2 *);

> > +	void (*lpm_cpu_power_gate)(struct imx_irq_gpcv2 *, u32, bool);

> > +	void (*lpm_plat_power_gate)(struct imx_irq_gpcv2 *, bool);

> > +	void (*set_mode)(struct imx_irq_gpcv2 *, enum gpcv2_mode mode);

> > +	void (*standby)(struct imx_irq_gpcv2 *);

> > +	void (*suspend)(struct imx_irq_gpcv2 *);

> > +	void (*set_slot)(struct imx_irq_gpcv2 *cd, u32 index,

> > +			enum gpcv2_slot m_core, bool mode, bool ack);

> > +	void (*clear_slots)(struct imx_irq_gpcv2 *);

> > +	void (*lpm_enable_core)(struct imx_irq_gpcv2 *,

> > +			bool enable, u32 offset);

> > +

> > +

> > +	void (*suspend_fn_in_ocram)(void __iomem *ocram_vbase);

> > +	void __iomem *ocram_vbase;

> 

> How many of these struct members are actually relevant to this driver and what

> is the purpose of those? A proper KernelDoc comment would shed some light on

> it.

> 

This struct defines the properties and functions that GPCv2 block provides. Since GPCv2 has
two key functions: Irq wakeup source management and power management, the 
intention of the struct is to share data and methods among irqchip, suspend, and cpuidle drivers.

> > +};

> > +

> > +void ca7_cpu_resume(void);

> > +void imx7_suspend(void __iomem *ocram_vbase);

> 

> How is that related to the irqchip driver?

> 

These two functions are used by suspend driver.

Thanks,
Shenwei


> Thanks,

> 

> 	tglx
Thomas Gleixner July 21, 2015, 4:51 p.m. UTC | #3
On Tue, 21 Jul 2015, Shenwei Wang wrote:
> > On Fri, 17 Jul 2015, Shenwei Wang wrote:
> > > +static struct imx_irq_gpcv2 *gpcv2_get_chip_data(void) {
> > > +	struct irq_data *data;
> > > +	int virq;
> > > +
> > > +	/* Since GPCv2 is the default IRQ domain, its private data can
> > > +	 * be gotten from any irq descriptor. Here we use interrupt #19
> > > +	 * which is for snvs-rtc.
> > > +	 */
> > 
> > Yuck. What kind of logic is that?
> > 
> > Use some random hardcoded number to find something which has been set by
> > this driver?
> > 
> > > +	virq = irq_find_mapping(0, 19);
> > > +
> > > +	for (data = irq_get_irq_data(virq); data;
> > > +	     data = data->parent_data) {
> > > +		if (!data->domain)
> > > +			continue;
> > > +
> > > +		if (!strcmp(data->domain->name, "GPCv2"))
> > 
> > So you are relying on internal knowledge of the irq domain code which sets the
> > domain name to the chip name if the domain name is not initialized by other
> > means.
> > 
> > Brilliant, NOT!
> > 
> > In other words you are interested in the irq chip associated with that domain and
> > not with the domain itself.
> > 
> > Care to explain what you are trying to do and why you think there are no better
> > ways to figure that out?
> > 
> When I wrote the driver, there were two options to let other modules like suspend 
> and cpuidle drivers to access this instance of imx_irq_gpcv2:
> Option #1 is to use the private data pointer of the irqdomain. 
> Option #2 is to export a global variable here.
> I selected option #1 because it could decouple this irq driver from those who may
> use this instance.

I do not see how that discouples anything. It makes stuff obscure.

> But option #2 is more direct and simple.

Well you don't have to export a global variable. All stuff referencing
this is in the driver itself.

I assume there is a single instance of that IP block in the chip. I
can't see how multiple instances would work.

So instead of doing a completely backwards lookup, you can simply have
a static variable visible to all functions in the driver:

static struct imx_irq_gpcv2 *imx_irq_gpcv2;

You store the pointer to your allocated data structure at the end of
your init function.

> > > +	for (i = 0; i < IMR_NUM; i++) {
> > 
> > Why is IMR_NUM a hard coded constant and not provided by DT?
> > 
> It can be provided by DT. However, as it is a fixed number and will
> never change once the Chip is produced I selected to hard code it.

Fair enough.
 
> > > +static int imx_gpcv2_irq_set_wake(struct irq_data *d, unsigned int
> > > +on) {
> > > +	unsigned int idx = d->hwirq / 32;
> > > +	struct imx_irq_gpcv2 *cd = d->chip_data;
> > > +	u32 mask, val;
> > > +	unsigned long flags;
> > > +	void __iomem *reg;
> > 
> > Can you come up with an even less readable way to arrange those declarations?
> > 
> Will change the declarations like following:
> 	u32 mask, val;
> 	unsigned long flags;
> 	void __iomem *reg;
> 
> 	unsigned int idx = d->hwirq / 32;
> 	struct imx_irq_gpcv2 *cd = d->chip_data;

My preferred way would be:

 	struct imx_irq_gpcv2 *cd = d->chip_data;
 	unsigned int idx = d->hwirq / 32;
 	unsigned long flags;
 	void __iomem *reg;
 	u32 mask, val;
 
but I dont insist as long as the style is consistent in all functions.
 
> > > +enum gpcv2_slot {
> > 
> > What is this enum for?
> > 
> It defined all the power domains that are controlled by GPCv2 block.

So it wants a proper documentation, right?
 
> > > +	CORE0_A7,
> > > +	CORE1_A7,
> > > +	SCU_A7,
> > > +	FAST_MEGA_MIX,
> > > +	MIPI_PHY,
> > > +	PCIE_PHY,
> > > +	USB_OTG1_PHY,
> > > +	USB_OTG2_PHY,
> > > +	USB_HSIC_PHY,
> > > +	CORE0_M4,
> > 
> > Namespace?
> >
> > > +};
> > 
> > > +struct imx_irq_gpcv2 {
> > > +	spinlock_t lock;
> > 
> >   raw_spinlock_t
> > 
> > > +	void __iomem *gpc_base;
> > > +	struct regmap *anatop;
> > > +	struct regmap *imx_src;
> > > +	u32 wakeup_sources[IMR_NUM];
> > > +	u32 enabled_irqs[IMR_NUM];
> > > +	u32 mfmix_mask[IMR_NUM];
> > > +	u32 wakeupmix_mask[IMR_NUM];
> > > +	u32 lpsrmix_mask[IMR_NUM];
> > > +	u32 cpu2wakeup;
> > > +	void (*lpm_env_setup)(struct imx_irq_gpcv2 *);
> > > +	void (*lpm_env_clean)(struct imx_irq_gpcv2 *);
> > > +	void (*lpm_cpu_power_gate)(struct imx_irq_gpcv2 *, u32, bool);
> > > +	void (*lpm_plat_power_gate)(struct imx_irq_gpcv2 *, bool);
> > > +	void (*set_mode)(struct imx_irq_gpcv2 *, enum gpcv2_mode mode);
> > > +	void (*standby)(struct imx_irq_gpcv2 *);
> > > +	void (*suspend)(struct imx_irq_gpcv2 *);
> > > +	void (*set_slot)(struct imx_irq_gpcv2 *cd, u32 index,
> > > +			enum gpcv2_slot m_core, bool mode, bool ack);
> > > +	void (*clear_slots)(struct imx_irq_gpcv2 *);
> > > +	void (*lpm_enable_core)(struct imx_irq_gpcv2 *,
> > > +			bool enable, u32 offset);
> > > +
> > > +
> > > +	void (*suspend_fn_in_ocram)(void __iomem *ocram_vbase);
> > > +	void __iomem *ocram_vbase;
> > 
> > How many of these struct members are actually relevant to this driver and what
> > is the purpose of those? A proper KernelDoc comment would shed some light on
> > it.
> > 

> This struct defines the properties and functions that GPCv2 block
> provides. Since GPCv2 has two key functions: Irq wakeup source
> management and power management, the intention of the struct is to
> share data and methods among irqchip, suspend, and cpuidle drivers.

I don't think this is a good idea. The cpuidle driver has nothing to
know about the internals of the irq driver and vice versa. Neither
does the suspend code.

If you failed to split that proper then your design is wrong.

Thanks,

	tglx
Shenwei Wang July 21, 2015, 6:41 p.m. UTC | #4
> -----Original Message-----

> From: Thomas Gleixner [mailto:tglx@linutronix.de]

> Sent: 2015?7?21? 11:52

> To: Wang Shenwei-B38339

> Cc: shawn.guo@linaro.org; jason@lakedaemon.net;

> linux-arm-kernel@lists.infradead.org; linux-kernel@vger.kernel.org

> Subject: RE: [PATCH V5 1/2] irqchip: imx-gpcv2: IMX GPCv2 driver for wakeup

> sources

> 

> On Tue, 21 Jul 2015, Shenwei Wang wrote:

> > > On Fri, 17 Jul 2015, Shenwei Wang wrote:

> > > > +static struct imx_irq_gpcv2 *gpcv2_get_chip_data(void) {

> > > > +	struct irq_data *data;

> > > > +	int virq;

> > > > +

> > > > +	/* Since GPCv2 is the default IRQ domain, its private data can

> > > > +	 * be gotten from any irq descriptor. Here we use interrupt #19

> > > > +	 * which is for snvs-rtc.

> > > > +	 */

> > >

> > > Yuck. What kind of logic is that?

> > >

> > > Use some random hardcoded number to find something which has been

> > > set by this driver?

> > >

> > > > +	virq = irq_find_mapping(0, 19);

> > > > +

> > > > +	for (data = irq_get_irq_data(virq); data;

> > > > +	     data = data->parent_data) {

> > > > +		if (!data->domain)

> > > > +			continue;

> > > > +

> > > > +		if (!strcmp(data->domain->name, "GPCv2"))

> > >

> > > So you are relying on internal knowledge of the irq domain code

> > > which sets the domain name to the chip name if the domain name is

> > > not initialized by other means.

> > >

> > > Brilliant, NOT!

> > >

> > > In other words you are interested in the irq chip associated with

> > > that domain and not with the domain itself.

> > >

> > > Care to explain what you are trying to do and why you think there

> > > are no better ways to figure that out?

> > >

> > When I wrote the driver, there were two options to let other modules

> > like suspend and cpuidle drivers to access this instance of imx_irq_gpcv2:

> > Option #1 is to use the private data pointer of the irqdomain.

> > Option #2 is to export a global variable here.

> > I selected option #1 because it could decouple this irq driver from

> > those who may use this instance.

> 

> I do not see how that discouples anything. It makes stuff obscure.

> 

> > But option #2 is more direct and simple.

> 

> Well you don't have to export a global variable. All stuff referencing this is in the

> driver itself.

> 

> I assume there is a single instance of that IP block in the chip. I can't see how

> multiple instances would work.

> 

> So instead of doing a completely backwards lookup, you can simply have a static

> variable visible to all functions in the driver:

> 

> static struct imx_irq_gpcv2 *imx_irq_gpcv2;

> 

> You store the pointer to your allocated data structure at the end of your init

> function.

> 

Your example is what I called option #2.
If you prefer to use this variable, I am also fine.

> > > > +	for (i = 0; i < IMR_NUM; i++) {

> > >

> > > Why is IMR_NUM a hard coded constant and not provided by DT?

> > >

> > It can be provided by DT. However, as it is a fixed number and will

> > never change once the Chip is produced I selected to hard code it.

> 

> Fair enough.

> 

> > > > +static int imx_gpcv2_irq_set_wake(struct irq_data *d, unsigned

> > > > +int

> > > > +on) {

> > > > +	unsigned int idx = d->hwirq / 32;

> > > > +	struct imx_irq_gpcv2 *cd = d->chip_data;

> > > > +	u32 mask, val;

> > > > +	unsigned long flags;

> > > > +	void __iomem *reg;

> > >

> > > Can you come up with an even less readable way to arrange those

> declarations?

> > >

> > Will change the declarations like following:

> > 	u32 mask, val;

> > 	unsigned long flags;

> > 	void __iomem *reg;

> >

> > 	unsigned int idx = d->hwirq / 32;

> > 	struct imx_irq_gpcv2 *cd = d->chip_data;

> 

> My preferred way would be:

> 

>  	struct imx_irq_gpcv2 *cd = d->chip_data;

>  	unsigned int idx = d->hwirq / 32;

>  	unsigned long flags;

>  	void __iomem *reg;

>  	u32 mask, val;

> 

Your style is much neater. I will adopt it.

> but I dont insist as long as the style is consistent in all functions.

> 

> > > > +enum gpcv2_slot {

> > >

> > > What is this enum for?

> > >

> > It defined all the power domains that are controlled by GPCv2 block.

> 

> So it wants a proper documentation, right?

> 

I will add the following comments above the enum declaration. Do you think it
is enough? 
"
GPCv2 has the following power domains, and each domain can be power-up
/power-down via GPC settings.

Core 0 of A7 power domain
Core1 of A7 power domain
SCU/L2 cache RAM of A7 power domain
Fastmix and megamix power domain
USB OTG1 PHY power domain
USB OTG2 PHY power domain
PCIE PHY power domain
USB HSIC PHY power domain
"

> > > > +	CORE0_A7,

> > > > +	CORE1_A7,

> > > > +	SCU_A7,

> > > > +	FAST_MEGA_MIX,

> > > > +	MIPI_PHY,

> > > > +	PCIE_PHY,

> > > > +	USB_OTG1_PHY,

> > > > +	USB_OTG2_PHY,

> > > > +	USB_HSIC_PHY,

> > > > +	CORE0_M4,

> > >

> > > Namespace?

> > >

> > > > +};

> > >

> > > > +struct imx_irq_gpcv2 {

> > > > +	spinlock_t lock;

> > >

> > >   raw_spinlock_t

> > >

> > > > +	void __iomem *gpc_base;

> > > > +	struct regmap *anatop;

> > > > +	struct regmap *imx_src;

> > > > +	u32 wakeup_sources[IMR_NUM];

> > > > +	u32 enabled_irqs[IMR_NUM];

> > > > +	u32 mfmix_mask[IMR_NUM];

> > > > +	u32 wakeupmix_mask[IMR_NUM];

> > > > +	u32 lpsrmix_mask[IMR_NUM];

> > > > +	u32 cpu2wakeup;

> > > > +	void (*lpm_env_setup)(struct imx_irq_gpcv2 *);

> > > > +	void (*lpm_env_clean)(struct imx_irq_gpcv2 *);

> > > > +	void (*lpm_cpu_power_gate)(struct imx_irq_gpcv2 *, u32, bool);

> > > > +	void (*lpm_plat_power_gate)(struct imx_irq_gpcv2 *, bool);

> > > > +	void (*set_mode)(struct imx_irq_gpcv2 *, enum gpcv2_mode mode);

> > > > +	void (*standby)(struct imx_irq_gpcv2 *);

> > > > +	void (*suspend)(struct imx_irq_gpcv2 *);

> > > > +	void (*set_slot)(struct imx_irq_gpcv2 *cd, u32 index,

> > > > +			enum gpcv2_slot m_core, bool mode, bool ack);

> > > > +	void (*clear_slots)(struct imx_irq_gpcv2 *);

> > > > +	void (*lpm_enable_core)(struct imx_irq_gpcv2 *,

> > > > +			bool enable, u32 offset);

> > > > +

> > > > +

> > > > +	void (*suspend_fn_in_ocram)(void __iomem *ocram_vbase);

> > > > +	void __iomem *ocram_vbase;

> > >

> > > How many of these struct members are actually relevant to this

> > > driver and what is the purpose of those? A proper KernelDoc comment

> > > would shed some light on it.

> > >

> 

> > This struct defines the properties and functions that GPCv2 block

> > provides. Since GPCv2 has two key functions: Irq wakeup source

> > management and power management, the intention of the struct is to

> > share data and methods among irqchip, suspend, and cpuidle drivers.

> 

> I don't think this is a good idea. The cpuidle driver has nothing to know about the

> internals of the irq driver and vice versa. Neither does the suspend code.

> 

> If you failed to split that proper then your design is wrong.

> 

The implementation has already been spitted totally. The question is if we use
the same structure among those drivers or not, since they do share some common data
like gpc_base address, enabled_irq, and mfmix_mask. The suspend and cpuidle driver
will use those data to decide the hardware power modes and the relating power down
sequence of the power domains. The structure is the abstract of the GPCv2 hardware, 
and the current struct declaration matches the low level hardware well. Although it is 
possible and easy to split it into two, it may introduce either redundant definition
for the common properties or have to create a global variable to enable them visible to
both the irqchip and the suspend codes.

Thanks,
Shenwei

> Thanks,

> 

> 	tglx

> 

>
Thomas Gleixner July 21, 2015, 9:37 p.m. UTC | #5
On Tue, 21 Jul 2015, Shenwei Wang wrote:
> > On Tue, 21 Jul 2015, Shenwei Wang wrote:
> > > This struct defines the properties and functions that GPCv2 block
> > > provides. Since GPCv2 has two key functions: Irq wakeup source
> > > management and power management, the intention of the struct is to
> > > share data and methods among irqchip, suspend, and cpuidle drivers.
> > 
> > I don't think this is a good idea. The cpuidle driver has nothing to know about the
> > internals of the irq driver and vice versa. Neither does the suspend code.
> > 
> > If you failed to split that proper then your design is wrong.
> > 
> The implementation has already been spitted totally. The question is
> if we use the same structure among those drivers or not, since they
> do share some common data like gpc_base address, enabled_irq, and
> mfmix_mask. The suspend and cpuidle driver will use those data to
> decide the hardware power modes and the relating power down sequence
> of the power domains. The structure is the abstract of the GPCv2
> hardware, and the current struct declaration matches the low level
> hardware well. Although it is possible and easy to split it into
> two, it may introduce either redundant definition for the common
> properties or have to create a global variable to enable them
> visible to both the irqchip and the suspend codes.

So the proper way to do this is:

Have a data structure which contains only the shared information. The
pointer to this structure can be global.

Have per driver data structures which contain the driver private
stuff.

Think about whether you need all the function pointers in one of the
structs. IOW, you need them only if a pointer can be changed at
runtime. If not you can call the function directly as I doubt that any
of these drivers can be modular.

Thanks,

	tglx
diff mbox

Patch

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 6de62a9..6a68cd5 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -158,3 +158,10 @@  config KEYSTONE_IRQ
 config MIPS_GIC
 	bool
 	select MIPS_CM
+
+config IMX_GPCV2
+	bool
+	select IRQ_DOMAIN
+	help
+	  Enables the wakeup IRQs for IMX platforms with GPCv2 block
+
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index dda4927..e6f4495 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -47,3 +47,4 @@  obj-$(CONFIG_KEYSTONE_IRQ)		+= irq-keystone.o
 obj-$(CONFIG_MIPS_GIC)			+= irq-mips-gic.o
 obj-$(CONFIG_ARCH_MEDIATEK)		+= irq-mtk-sysirq.o
 obj-$(CONFIG_ARCH_DIGICOLOR)		+= irq-digicolor.o
+obj-$(CONFIG_IMX_GPCV2)			+= irq-imx-gpcv2.o
diff --git a/drivers/irqchip/irq-imx-gpcv2.c b/drivers/irqchip/irq-imx-gpcv2.c
new file mode 100644
index 0000000..ab64e94
--- /dev/null
+++ b/drivers/irqchip/irq-imx-gpcv2.c
@@ -0,0 +1,311 @@ 
+
+/*
+ * Copyright (C) 2015 Freescale Semiconductor, Inc.
+ *
+ * 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/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/slab.h>
+#include <linux/syscore_ops.h>
+#include "irqchip.h"
+
+#include <soc/imx/gpcv2.h>
+
+static struct imx_irq_gpcv2 *gpcv2_get_chip_data(void)
+{
+	struct irq_data *data;
+	int virq;
+
+	/* Since GPCv2 is the default IRQ domain, its private data can
+	 * be gotten from any irq descriptor. Here we use interrupt #19
+	 * which is for snvs-rtc.
+	 */
+	virq = irq_find_mapping(0, 19);
+
+	for (data = irq_get_irq_data(virq); data;
+	     data = data->parent_data) {
+		if (!data->domain)
+			continue;
+
+		if (!strcmp(data->domain->name, "GPCv2"))
+			return data->chip_data;
+	}
+
+	return 0;
+}
+
+static int gpcv2_wakeup_source_save(void)
+{
+	struct imx_irq_gpcv2 *cd;
+	void __iomem *reg;
+	int i;
+
+	cd = gpcv2_get_chip_data();
+	if (!cd)
+		return 0;
+
+	for (i = 0; i < IMR_NUM; i++) {
+		reg = cd->gpc_base + cd->cpu2wakeup + i * 4;
+		cd->enabled_irqs[i] = readl_relaxed(reg);
+		writel_relaxed(cd->wakeup_sources[i], reg);
+	}
+
+	pr_devel("%s ----\r\n", __func__);
+	pr_devel("Enabled IRQ:\t %08X %08X %08X %08X\r\n",
+			cd->enabled_irqs[0],
+			cd->enabled_irqs[1],
+			cd->enabled_irqs[2],
+			cd->enabled_irqs[3]);
+	pr_devel("Wakeup Sources:\t %08X %08X %08X %08X\r\n",
+			cd->wakeup_sources[0],
+			cd->wakeup_sources[1],
+			cd->wakeup_sources[2],
+			cd->wakeup_sources[3]);
+	return 0;
+}
+
+static void gpcv2_wakeup_source_restore(void)
+{
+	struct imx_irq_gpcv2 *cd;
+	void __iomem *reg;
+	int i;
+
+	cd = gpcv2_get_chip_data();
+	if (!cd)
+		return;
+
+	for (i = 0; i < IMR_NUM; i++) {
+		reg = cd->gpc_base + cd->cpu2wakeup + i * 4;
+		writel_relaxed(cd->enabled_irqs[i], reg);
+		cd->wakeup_sources[i] = ~0;
+	}
+
+	pr_devel("%s ----\r\n", __func__);
+	pr_devel("Enabled IRQ:\t %08X %08X %08X %08X\r\n",
+			cd->enabled_irqs[0],
+			cd->enabled_irqs[1],
+			cd->enabled_irqs[2],
+			cd->enabled_irqs[3]);
+	pr_devel("Wakeup Sources:\t %08X %08X %08X %08X\r\n",
+			cd->wakeup_sources[0],
+			cd->wakeup_sources[1],
+			cd->wakeup_sources[2],
+			cd->wakeup_sources[3]);
+}
+
+static struct syscore_ops imx_gpcv2_syscore_ops = {
+	.suspend	= gpcv2_wakeup_source_save,
+	.resume		= gpcv2_wakeup_source_restore,
+};
+
+static int imx_gpcv2_irq_set_wake(struct irq_data *d, unsigned int on)
+{
+	unsigned int idx = d->hwirq / 32;
+	struct imx_irq_gpcv2 *cd = d->chip_data;
+	u32 mask, val;
+	unsigned long flags;
+	void __iomem *reg;
+
+	spin_lock_irqsave(&cd->lock, flags);
+	reg = cd->gpc_base + cd->cpu2wakeup + idx * 4;
+	mask = 1 << d->hwirq % 32;
+	val = cd->wakeup_sources[idx];
+
+	cd->wakeup_sources[idx] = on ? (val & ~mask) : (val | mask);
+	spin_unlock_irqrestore(&cd->lock, flags);
+
+	/*
+	 * Do *not* call into the parent, as the GIC doesn't have any
+	 * wake-up facility...
+	 */
+
+	return 0;
+}
+
+
+static void imx_gpcv2_irq_unmask(struct irq_data *d)
+{
+	void __iomem *reg;
+	struct imx_irq_gpcv2 *cd = d->chip_data;
+	u32 val;
+	unsigned long flags;
+
+	spin_lock_irqsave(&cd->lock, flags);
+	reg = cd->gpc_base + cd->cpu2wakeup + d->hwirq / 32 * 4;
+	val = readl_relaxed(reg);
+	val &= ~(1 << d->hwirq % 32);
+	writel_relaxed(val, reg);
+	irq_chip_unmask_parent(d);
+	spin_unlock_irqrestore(&cd->lock, flags);
+}
+
+static void imx_gpcv2_irq_mask(struct irq_data *d)
+{
+	void __iomem *reg;
+	struct imx_irq_gpcv2 *cd = d->chip_data;
+	u32 val;
+	unsigned long flags;
+
+	spin_lock_irqsave(&cd->lock, flags);
+	reg = cd->gpc_base + cd->cpu2wakeup + d->hwirq / 32 * 4;
+	val = readl_relaxed(reg);
+	val |= 1 << (d->hwirq % 32);
+	writel_relaxed(val, reg);
+
+	irq_chip_mask_parent(d);
+	spin_unlock_irqrestore(&cd->lock, flags);
+}
+
+
+static struct irq_chip imx_gpcv2_irq_chip = {
+	.name			= "GPCv2",
+	.irq_eoi		= irq_chip_eoi_parent,
+	.irq_mask		= imx_gpcv2_irq_mask,
+	.irq_unmask		= imx_gpcv2_irq_unmask,
+	.irq_retrigger		= irq_chip_retrigger_hierarchy,
+	.irq_set_wake		= imx_gpcv2_irq_set_wake,
+#ifdef CONFIG_SMP
+	.irq_set_affinity	= irq_chip_set_affinity_parent,
+#endif
+};
+
+static int imx_gpcv2_domain_xlate(struct irq_domain *domain,
+				struct device_node *controller,
+				const u32 *intspec,
+				unsigned int intsize,
+				unsigned long *out_hwirq,
+				unsigned int *out_type)
+{
+	if (domain->of_node != controller)
+		return -EINVAL;	/* Shouldn't happen, really... */
+	if (intsize != 3)
+		return -EINVAL;	/* Not GIC compliant */
+	if (intspec[0] != 0)
+		return -EINVAL;	/* No PPI should point to this domain */
+
+	*out_hwirq = intspec[1];
+	*out_type = intspec[2];
+	return 0;
+}
+
+static int imx_gpcv2_domain_alloc(struct irq_domain *domain,
+				  unsigned int irq,
+				  unsigned int nr_irqs, void *data)
+{
+	struct of_phandle_args *args = data;
+	struct of_phandle_args parent_args;
+	irq_hw_number_t hwirq;
+	int i;
+
+	if (args->args_count != 3)
+		return -EINVAL;	/* Not GIC compliant */
+	if (args->args[0] != 0)
+		return -EINVAL;	/* No PPI should point to this domain */
+
+	hwirq = args->args[1];
+	if (hwirq >= GPC_MAX_IRQS)
+		return -EINVAL;	/* Can't deal with this */
+
+	for (i = 0; i < nr_irqs; i++) {
+		irq_domain_set_hwirq_and_chip(domain, irq + i, hwirq + i,
+				&imx_gpcv2_irq_chip, domain->host_data);
+	}
+	parent_args = *args;
+	parent_args.np = domain->parent->of_node;
+	return irq_domain_alloc_irqs_parent(domain, irq, nr_irqs, &parent_args);
+}
+
+static struct irq_domain_ops imx_gpcv2_irq_domain_ops = {
+	.xlate	= imx_gpcv2_domain_xlate,
+	.alloc	= imx_gpcv2_domain_alloc,
+	.free	= irq_domain_free_irqs_common,
+};
+
+
+
+static int __init imx_gpcv2_irqchip_init(struct device_node *node,
+			       struct device_node *parent)
+{
+	struct irq_domain *parent_domain, *domain;
+	int i, val;
+	struct imx_irq_gpcv2 *cd;
+
+	if (!parent) {
+		pr_err("%s: no parent, giving up\n", node->full_name);
+		return -ENODEV;
+	}
+
+	parent_domain = irq_find_host(parent);
+	if (!parent_domain) {
+		pr_err("%s: unable to obtain parent domain\n", node->full_name);
+		return -ENXIO;
+	}
+
+	cd = kzalloc(sizeof(struct imx_irq_gpcv2), GFP_KERNEL);
+	BUG_ON(!cd);
+
+	cd->gpc_base = of_iomap(node, 0);
+	if (!cd->gpc_base) {
+		pr_err("fsl-gpcv2: unable to map gpc registers\n");
+		kzfree(cd);
+		return -ENOMEM;
+	}
+
+	domain = irq_domain_add_hierarchy(parent_domain, 0, GPC_MAX_IRQS,
+				node, &imx_gpcv2_irq_domain_ops, cd);
+	if (!domain) {
+		iounmap(cd->gpc_base);
+		kzfree(cd);
+		return -ENOMEM;
+	}
+	irq_set_default_host(domain);
+
+	/* Initially mask all interrupts */
+	for (i = 0; i < IMR_NUM; i++) {
+		writel_relaxed(~0, cd->gpc_base + GPC_IMR1_CORE0 + i * 4);
+		writel_relaxed(~0, cd->gpc_base + GPC_IMR1_CORE1 + i * 4);
+		cd->wakeup_sources[i] = ~0;
+	}
+
+	/* Let CORE0 as the default CPU to wake up by GPC */
+	cd->cpu2wakeup = GPC_IMR1_CORE0;
+
+	/*
+	 * Due to hardware design requirement, need to make sure GPR
+	 * interrupt(#32) is unmasked during RUN mode to avoid entering
+	 * DSM by mistake.
+	 */
+	writel_relaxed(~0x1, cd->gpc_base + cd->cpu2wakeup);
+
+	/* Mask the wakeup sources in M/F power domain */
+	cd->mfmix_mask[0] = 0x54010000;
+	cd->mfmix_mask[1] = 0xc00;
+	cd->mfmix_mask[2] = 0x0;
+	cd->mfmix_mask[3] = 0x400010;
+
+	/* only external IRQs to wake up LPM and core 0/1 */
+	val = readl_relaxed(cd->gpc_base + GPC_LPCR_A7_BSC);
+	val |= BM_LPCR_A7_BSC_IRQ_SRC_A7_WAKEUP;
+	writel_relaxed(val, cd->gpc_base + GPC_LPCR_A7_BSC);
+	/* mask m4 dsm trigger */
+	writel_relaxed(readl_relaxed(cd->gpc_base + GPC_LPCR_M4) |
+		BM_LPCR_M4_MASK_DSM_TRIGGER, cd->gpc_base + GPC_LPCR_M4);
+	/* set mega/fast mix in A7 domain */
+	writel_relaxed(0x1, cd->gpc_base + GPC_PGC_CPU_MAPPING);
+	/* set SCU timing */
+	writel_relaxed((0x59 << 10) | 0x5B | (0x51 << 20),
+		cd->gpc_base + GPC_PGC_SCU_TIMING);
+
+	register_syscore_ops(&imx_gpcv2_syscore_ops);
+
+	return 0;
+}
+
+
+IRQCHIP_DECLARE(imx_gpcv2, "fsl,imx7d-gpc", imx_gpcv2_irqchip_init);
+
+
diff --git a/include/soc/imx/gpcv2.h b/include/soc/imx/gpcv2.h
new file mode 100644
index 0000000..aec862cd
--- /dev/null
+++ b/include/soc/imx/gpcv2.h
@@ -0,0 +1,137 @@ 
+/*
+ * Copyright (C) 2015 Freescale Semiconductor, Inc.
+ *
+ * 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.
+ */
+
+#ifndef __SOC_IMX_GPCV2_H__
+#define __SOC_IMX_GPCV2_H__
+
+
+#define IMR_NUM			4
+#define GPC_MAX_IRQS            (IMR_NUM * 32)
+
+#define GPC_LPCR_A7_BSC		0x0
+#define GPC_LPCR_M4		0x8
+
+#define GPC_IMR1_CORE0		0x30
+#define GPC_IMR1_CORE1		0x40
+
+#define GPC_PGC_CPU_MAPPING	0xec
+#define GPC_PGC_SCU_TIMING	0x890
+
+#define BM_LPCR_A7_BSC_IRQ_SRC_A7_WAKEUP	0x70000000
+#define BM_LPCR_M4_MASK_DSM_TRIGGER		0x80000000
+
+
+#define GPC_LPCR_A7_AD		0x4
+#define GPC_SLPCR		0x14
+#define GPC_PGC_ACK_SEL_A7	0x24
+
+#define GPC_SLOT0_CFG		0xb0
+
+#define GPC_PGC_C0		0x800
+#define GPC_PGC_SCU_TIMING	0x890
+#define GPC_PGC_C1		0x840
+#define GPC_PGC_SCU		0x880
+#define GPC_PGC_FM		0xa00
+
+#define BM_LPCR_A7_BSC_CPU_CLK_ON_LPM		0x4000
+#define BM_LPCR_A7_BSC_LPM1			0xc
+#define BM_LPCR_A7_BSC_LPM0			0x3
+#define BP_LPCR_A7_BSC_LPM1			2
+#define BP_LPCR_A7_BSC_LPM0			0
+
+#define BM_SLPCR_EN_DSM				0x80000000
+#define BM_SLPCR_RBC_EN				0x40000000
+#define BM_SLPCR_VSTBY				0x4
+#define BM_SLPCR_SBYOS				0x2
+#define BM_SLPCR_BYPASS_PMIC_READY		0x1
+
+
+#define BM_LPCR_A7_AD_L2PGE			0x10000
+#define BM_LPCR_A7_AD_EN_C1_PUP			0x800
+#define BM_LPCR_A7_AD_EN_C1_IRQ_PUP		0x400
+#define BM_LPCR_A7_AD_EN_C0_PUP			0x200
+#define BM_LPCR_A7_AD_EN_C0_IRQ_PUP		0x100
+#define BM_LPCR_A7_AD_EN_PLAT_PDN		0x10
+#define BM_LPCR_A7_AD_EN_C1_PDN			0x8
+#define BM_LPCR_A7_AD_EN_C1_WFI_PDN		0x4
+#define BM_LPCR_A7_AD_EN_C0_PDN			0x2
+#define BM_LPCR_A7_AD_EN_C0_WFI_PDN		0x1
+
+#define BM_GPC_PGC_ACK_SEL_A7_DUMMY_PUP_ACK	0x80000000
+#define BM_GPC_PGC_ACK_SEL_A7_DUMMY_PDN_ACK	0x8000
+
+#define MAX_SLOT_NUMBER				10
+#define A7_LPM_WAIT				0x5
+#define A7_LPM_STOP				0xa
+
+
+#define REG_SET		0x4
+#define REG_CLR		0x8
+
+#define ANADIG_ARM_PLL		0x60
+#define ANADIG_DDR_PLL		0x70
+#define ANADIG_SYS_PLL		0xb0
+#define ANADIG_ENET_PLL		0xe0
+#define ANADIG_AUDIO_PLL	0xf0
+#define ANADIG_VIDEO_PLL	0x130
+
+
+enum gpcv2_mode {
+	WAIT_CLOCKED,		/* wfi only */
+	WAIT_UNCLOCKED,		/* WAIT */
+	WAIT_UNCLOCKED_POWER_OFF,	/* WAIT + SRPG */
+	STOP_POWER_ON,		/* just STOP */
+	STOP_POWER_OFF,		/* STOP + SRPG */
+};
+
+enum gpcv2_slot {
+	CORE0_A7,
+	CORE1_A7,
+	SCU_A7,
+	FAST_MEGA_MIX,
+	MIPI_PHY,
+	PCIE_PHY,
+	USB_OTG1_PHY,
+	USB_OTG2_PHY,
+	USB_HSIC_PHY,
+	CORE0_M4,
+};
+
+struct imx_irq_gpcv2 {
+	spinlock_t lock;
+	void __iomem *gpc_base;
+	struct regmap *anatop;
+	struct regmap *imx_src;
+	u32 wakeup_sources[IMR_NUM];
+	u32 enabled_irqs[IMR_NUM];
+	u32 mfmix_mask[IMR_NUM];
+	u32 wakeupmix_mask[IMR_NUM];
+	u32 lpsrmix_mask[IMR_NUM];
+	u32 cpu2wakeup;
+	void (*lpm_env_setup)(struct imx_irq_gpcv2 *);
+	void (*lpm_env_clean)(struct imx_irq_gpcv2 *);
+	void (*lpm_cpu_power_gate)(struct imx_irq_gpcv2 *, u32, bool);
+	void (*lpm_plat_power_gate)(struct imx_irq_gpcv2 *, bool);
+	void (*set_mode)(struct imx_irq_gpcv2 *, enum gpcv2_mode mode);
+	void (*standby)(struct imx_irq_gpcv2 *);
+	void (*suspend)(struct imx_irq_gpcv2 *);
+	void (*set_slot)(struct imx_irq_gpcv2 *cd, u32 index,
+			enum gpcv2_slot m_core, bool mode, bool ack);
+	void (*clear_slots)(struct imx_irq_gpcv2 *);
+	void (*lpm_enable_core)(struct imx_irq_gpcv2 *,
+			bool enable, u32 offset);
+
+
+	void (*suspend_fn_in_ocram)(void __iomem *ocram_vbase);
+	void __iomem *ocram_vbase;
+};
+
+void ca7_cpu_resume(void);
+void imx7_suspend(void __iomem *ocram_vbase);
+
+#endif  /* __SOC_IMX_GPCV2_H__ */