diff mbox series

[V6,2/4] firmware: imx: enable imx scu general irq function

Message ID 1554777487-31075-2-git-send-email-Anson.Huang@nxp.com
State Superseded, archived
Headers show
Series None | expand

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Context Check Description
robh/checkpatch success

Commit Message

Anson Huang April 9, 2019, 2:43 a.m. UTC 
The System Controller Firmware (SCFW) controls RTC, thermal
and WDOG etc., these resources' interrupt function are managed
by SCU. When any IRQ pending, SCU will notify Linux via MU general
interrupt channel #3, and Linux kernel needs to call SCU APIs
to get IRQ status and notify each module to handle the interrupt.

Since there is no data transmission for SCU IRQ notification, so
doorbell mode is used for this MU channel, and SCU driver will
use notifier mechanism to broadcast to every module which registers
the SCU block notifier.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
---
Changes since V5:
	- use ATOMIC_NOTIFIER instead of BLOCKING_NOTIFIER for irq notification;
	- add memory free for failed case to avoid memory leak;
	- add new API imx_scu_irq_enable() for modules to enable/disable their own irqs.
---
 drivers/firmware/imx/Makefile      |   2 +-
 drivers/firmware/imx/imx-scu-irq.c | 166 +++++++++++++++++++++++++++++++++++++
 drivers/firmware/imx/imx-scu.c     |   6 ++
 include/linux/firmware/imx/sci.h   |   5 ++
 4 files changed, 178 insertions(+), 1 deletion(-)
 create mode 100644 drivers/firmware/imx/imx-scu-irq.c

Comments

Dong Aisheng April 9, 2019, 3:20 a.m. UTC | #1 
> From: Anson Huang
> Sent: Tuesday, April 9, 2019 10:43 AM
> Subject: [PATCH V6 2/4] firmware: imx: enable imx scu general irq function
> 
> The System Controller Firmware (SCFW) controls RTC, thermal and WDOG etc.,
> these resources' interrupt function are managed by SCU. When any IRQ
> pending, SCU will notify Linux via MU general interrupt channel #3, and Linux
> kernel needs to call SCU APIs to get IRQ status and notify each module to
> handle the interrupt.
> 
> Since there is no data transmission for SCU IRQ notification, so doorbell mode
> is used for this MU channel, and SCU driver will use notifier mechanism to
> broadcast to every module which registers the SCU block notifier.
> 
> Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
> ---
> Changes since V5:
> 	- use ATOMIC_NOTIFIER instead of BLOCKING_NOTIFIER for irq
> notification;
> 	- add memory free for failed case to avoid memory leak;
> 	- add new API imx_scu_irq_enable() for modules to enable/disable their
> own irqs.
> ---
>  drivers/firmware/imx/Makefile      |   2 +-
>  drivers/firmware/imx/imx-scu-irq.c | 166
> +++++++++++++++++++++++++++++++++++++
>  drivers/firmware/imx/imx-scu.c     |   6 ++
>  include/linux/firmware/imx/sci.h   |   5 ++
>  4 files changed, 178 insertions(+), 1 deletion(-)  create mode 100644
> drivers/firmware/imx/imx-scu-irq.c
> 
> diff --git a/drivers/firmware/imx/Makefile b/drivers/firmware/imx/Makefile
> index 1b2e15b..802c4ad 100644
> --- a/drivers/firmware/imx/Makefile
> +++ b/drivers/firmware/imx/Makefile
> @@ -1,3 +1,3 @@
>  # SPDX-License-Identifier: GPL-2.0
> -obj-$(CONFIG_IMX_SCU)		+= imx-scu.o misc.o
> +obj-$(CONFIG_IMX_SCU)		+= imx-scu.o misc.o imx-scu-irq.o
>  obj-$(CONFIG_IMX_SCU_PD)	+= scu-pd.o
> diff --git a/drivers/firmware/imx/imx-scu-irq.c
> b/drivers/firmware/imx/imx-scu-irq.c
> new file mode 100644
> index 0000000..4000c63
> --- /dev/null
> +++ b/drivers/firmware/imx/imx-scu-irq.c
> @@ -0,0 +1,166 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright 2019 NXP
> + *
> + * Implementation of the SCU IRQ functions using MU.
> + *
> + */
> +
> +#include <dt-bindings/firmware/imx/rsrc.h> #include
> +<linux/firmware/imx/ipc.h> #include <linux/mailbox_client.h>
> +
> +#define IMX_SC_IRQ_FUNC_ENABLE	1
> +#define IMX_SC_IRQ_FUNC_STATUS	2
> +#define IMX_SC_IRQ_NUM_GROUP	4
> +
> +static u32 mu_resource_id;
> +
> +struct imx_sc_msg_irq_get_status {
> +	struct imx_sc_rpc_msg hdr;
> +	union {
> +		struct {
> +			u16 resource;
> +			u8 group;
> +			u8 reserved;
> +		} __packed req;
> +		struct {
> +			u32 status;
> +		} resp;
> +	} data;
> +};
> +
> +struct imx_sc_msg_irq_enable {
> +	struct imx_sc_rpc_msg hdr;
> +	u32 mask;
> +	u16 resource;
> +	u8 group;
> +	u8 enable;
> +} __packed;
> +
> +static struct imx_sc_ipc *imx_sc_irq_ipc_handle; static struct
> +work_struct imx_sc_irq_work; static
> +ATOMIC_NOTIFIER_HEAD(imx_scu_irq_notifier_chain);
> +
> +int imx_scu_irq_register_notifier(struct notifier_block *nb) {
> +	return atomic_notifier_chain_register(
> +		&imx_scu_irq_notifier_chain, nb);
> +}
> +EXPORT_SYMBOL(imx_scu_irq_register_notifier);
> +
> +int imx_scu_irq_unregister_notifier(struct notifier_block *nb) {
> +	return atomic_notifier_chain_unregister(
> +		&imx_scu_irq_notifier_chain, nb);
> +}
> +EXPORT_SYMBOL(imx_scu_irq_unregister_notifier);
> +
> +static int imx_scu_irq_notifier_call_chain(unsigned long status, u8
> +*group) {
> +	return atomic_notifier_call_chain(&imx_scu_irq_notifier_chain,
> +		status, (void *)group);
> +}
> +
> +static void imx_scu_irq_work_handler(struct work_struct *work) {
> +	struct imx_sc_msg_irq_get_status msg;
> +	struct imx_sc_rpc_msg *hdr = &msg.hdr;
> +	u32 irq_status;
> +	int ret;
> +	u8 i;
> +
> +	for (i = 0; i < IMX_SC_IRQ_NUM_GROUP; i++) {
> +		hdr->ver = IMX_SC_RPC_VERSION;
> +		hdr->svc = IMX_SC_RPC_SVC_IRQ;
> +		hdr->func = IMX_SC_IRQ_FUNC_STATUS;
> +		hdr->size = 2;
> +
> +		msg.data.req.resource = mu_resource_id;
> +		msg.data.req.group = i;
> +
> +		ret = imx_scu_call_rpc(imx_sc_irq_ipc_handle, &msg, true);
> +		if (ret) {
> +			pr_err("get irq group %d status failed, ret %d\n",
> +			       i, ret);
> +			return;
> +		}
> +
> +		irq_status = msg.data.resp.status;
> +		if (!irq_status)
> +			continue;
> +
> +		imx_scu_irq_notifier_call_chain(irq_status, &i);
> +	}
> +}
> +
> +void imx_scu_irq_enable(u8 group, u32 mask, u8 enable) {

Why should this be a void return?

Besides that, a nitpick better rename to imx_scu_irq_group_enable
to distinguish with the exist general irq enable.

Regards
Dong Aisheng

> +	struct imx_sc_msg_irq_enable msg;
> +	struct imx_sc_rpc_msg *hdr = &msg.hdr;
> +	int ret;
> +
> +	hdr->ver = IMX_SC_RPC_VERSION;
> +	hdr->svc = IMX_SC_RPC_SVC_IRQ;
> +	hdr->func = IMX_SC_IRQ_FUNC_ENABLE;
> +	hdr->size = 3;
> +
> +	msg.resource = mu_resource_id;
> +	msg.group = group;
> +	msg.mask = mask;
> +	msg.enable = enable;
> +
> +	ret = imx_scu_call_rpc(imx_sc_irq_ipc_handle, &msg, true);
> +	if (ret)
> +		pr_err("enable irq failed, group %d, mask %d, ret %d\n",
> +			group, mask, ret);
> +}
> +EXPORT_SYMBOL(imx_scu_irq_enable);
> +
> +static void imx_scu_irq_callback(struct mbox_client *c, void *msg) {
> +	schedule_work(&imx_sc_irq_work);
> +}
> +
> +int imx_scu_enable_general_irq_channel(struct device *dev) {
> +	struct of_phandle_args spec;
> +	struct mbox_client *cl;
> +	struct mbox_chan *ch;
> +	int ret = 0, i = 0;
> +
> +	ret = imx_scu_get_handle(&imx_sc_irq_ipc_handle);
> +	if (ret)
> +		return ret;
> +
> +	cl = devm_kzalloc(dev, sizeof(*cl), GFP_KERNEL);
> +	if (!cl)
> +		return -ENOMEM;
> +
> +	cl->dev = dev;
> +	cl->rx_callback = imx_scu_irq_callback;
> +
> +	/* SCU general IRQ uses general interrupt channel 3 */
> +	ch = mbox_request_channel_byname(cl, "gip3");
> +	if (IS_ERR(ch)) {
> +		ret = PTR_ERR(ch);
> +		dev_err(dev, "failed to request mbox chan gip3, ret %d\n", ret);
> +		devm_kfree(dev, cl);
> +		return ret;
> +	}
> +
> +	INIT_WORK(&imx_sc_irq_work, imx_scu_irq_work_handler);
> +
> +	if (!of_parse_phandle_with_args(dev->of_node, "mboxes",
> +				       "#mbox-cells", 0, &spec))
> +		i = of_alias_get_id(spec.np, "mu");
> +
> +	/* use mu1 as general mu irq channel if failed */
> +	if (i < 0)
> +		i = 1;
> +
> +	mu_resource_id = IMX_SC_R_MU_0A + i;
> +
> +	return ret;
> +}
> +EXPORT_SYMBOL(imx_scu_enable_general_irq_channel);
> diff --git a/drivers/firmware/imx/imx-scu.c b/drivers/firmware/imx/imx-scu.c
> index 2bb1a19..04a24a8 100644
> --- a/drivers/firmware/imx/imx-scu.c
> +++ b/drivers/firmware/imx/imx-scu.c
> @@ -10,6 +10,7 @@
>  #include <linux/err.h>
>  #include <linux/firmware/imx/types.h>
>  #include <linux/firmware/imx/ipc.h>
> +#include <linux/firmware/imx/sci.h>
>  #include <linux/interrupt.h>
>  #include <linux/irq.h>
>  #include <linux/kernel.h>
> @@ -246,6 +247,11 @@ static int imx_scu_probe(struct platform_device
> *pdev)
> 
>  	imx_sc_ipc_handle = sc_ipc;
> 
> +	ret = imx_scu_enable_general_irq_channel(dev);
> +	if (ret)
> +		dev_warn(dev,
> +			"failed to enable general irq channel: %d\n", ret);
> +
>  	dev_info(dev, "NXP i.MX SCU Initialized\n");
> 
>  	return devm_of_platform_populate(dev); diff --git
> a/include/linux/firmware/imx/sci.h b/include/linux/firmware/imx/sci.h
> index ebc5509..4100be7 100644
> --- a/include/linux/firmware/imx/sci.h
> +++ b/include/linux/firmware/imx/sci.h
> @@ -15,4 +15,9 @@
> 
>  #include <linux/firmware/imx/svc/misc.h>  #include
> <linux/firmware/imx/svc/pm.h>
> +
> +int imx_scu_enable_general_irq_channel(struct device *dev); int
> +imx_scu_irq_register_notifier(struct notifier_block *nb); int
> +imx_scu_irq_unregister_notifier(struct notifier_block *nb); void
> +imx_scu_irq_enable(u8 group, u32 mask, u8 enable);
>  #endif /* _SC_SCI_H */
> --
> 2.7.4
Anson Huang April 9, 2019, 3:34 a.m. UTC | #2 
Best Regards!
Anson Huang

> -----Original Message-----
> From: Aisheng Dong
> Sent: 2019年4月9日 11:21
> To: Anson Huang <anson.huang@nxp.com>; robh+dt@kernel.org;
> mark.rutland@arm.com; shawnguo@kernel.org; s.hauer@pengutronix.de;
> kernel@pengutronix.de; festevam@gmail.com; a.zummo@towertech.it;
> alexandre.belloni@bootlin.com; ulf.hansson@linaro.org; sboyd@kernel.org;
> Peng Fan <peng.fan@nxp.com>; Daniel Baluta <daniel.baluta@nxp.com>;
> devicetree@vger.kernel.org; linux-kernel@vger.kernel.org; linux-arm-
> kernel@lists.infradead.org; linux-rtc@vger.kernel.org
> Cc: dl-linux-imx <linux-imx@nxp.com>
> Subject: RE: [PATCH V6 2/4] firmware: imx: enable imx scu general irq
> function
> 
> > From: Anson Huang
> > Sent: Tuesday, April 9, 2019 10:43 AM
> > Subject: [PATCH V6 2/4] firmware: imx: enable imx scu general irq
> > function
> >
> > The System Controller Firmware (SCFW) controls RTC, thermal and WDOG
> > etc., these resources' interrupt function are managed by SCU. When any
> > IRQ pending, SCU will notify Linux via MU general interrupt channel
> > #3, and Linux kernel needs to call SCU APIs to get IRQ status and
> > notify each module to handle the interrupt.
> >
> > Since there is no data transmission for SCU IRQ notification, so
> > doorbell mode is used for this MU channel, and SCU driver will use
> > notifier mechanism to broadcast to every module which registers the SCU
> block notifier.
> >
> > Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
> > ---
> > Changes since V5:
> > 	- use ATOMIC_NOTIFIER instead of BLOCKING_NOTIFIER for irq
> > notification;
> > 	- add memory free for failed case to avoid memory leak;
> > 	- add new API imx_scu_irq_enable() for modules to enable/disable
> > their own irqs.
> > ---
> >  drivers/firmware/imx/Makefile      |   2 +-
> >  drivers/firmware/imx/imx-scu-irq.c | 166
> > +++++++++++++++++++++++++++++++++++++
> >  drivers/firmware/imx/imx-scu.c     |   6 ++
> >  include/linux/firmware/imx/sci.h   |   5 ++
> >  4 files changed, 178 insertions(+), 1 deletion(-)  create mode 100644
> > drivers/firmware/imx/imx-scu-irq.c
> >
> > diff --git a/drivers/firmware/imx/Makefile
> > b/drivers/firmware/imx/Makefile index 1b2e15b..802c4ad 100644
> > --- a/drivers/firmware/imx/Makefile
> > +++ b/drivers/firmware/imx/Makefile
> > @@ -1,3 +1,3 @@
> >  # SPDX-License-Identifier: GPL-2.0
> > -obj-$(CONFIG_IMX_SCU)		+= imx-scu.o misc.o
> > +obj-$(CONFIG_IMX_SCU)		+= imx-scu.o misc.o imx-scu-irq.o
> >  obj-$(CONFIG_IMX_SCU_PD)	+= scu-pd.o
> > diff --git a/drivers/firmware/imx/imx-scu-irq.c
> > b/drivers/firmware/imx/imx-scu-irq.c
> > new file mode 100644
> > index 0000000..4000c63
> > --- /dev/null
> > +++ b/drivers/firmware/imx/imx-scu-irq.c
> > @@ -0,0 +1,166 @@
> > +// SPDX-License-Identifier: GPL-2.0+
> > +/*
> > + * Copyright 2019 NXP
> > + *
> > + * Implementation of the SCU IRQ functions using MU.
> > + *
> > + */
> > +
> > +#include <dt-bindings/firmware/imx/rsrc.h> #include
> > +<linux/firmware/imx/ipc.h> #include <linux/mailbox_client.h>
> > +
> > +#define IMX_SC_IRQ_FUNC_ENABLE	1
> > +#define IMX_SC_IRQ_FUNC_STATUS	2
> > +#define IMX_SC_IRQ_NUM_GROUP	4
> > +
> > +static u32 mu_resource_id;
> > +
> > +struct imx_sc_msg_irq_get_status {
> > +	struct imx_sc_rpc_msg hdr;
> > +	union {
> > +		struct {
> > +			u16 resource;
> > +			u8 group;
> > +			u8 reserved;
> > +		} __packed req;
> > +		struct {
> > +			u32 status;
> > +		} resp;
> > +	} data;
> > +};
> > +
> > +struct imx_sc_msg_irq_enable {
> > +	struct imx_sc_rpc_msg hdr;
> > +	u32 mask;
> > +	u16 resource;
> > +	u8 group;
> > +	u8 enable;
> > +} __packed;
> > +
> > +static struct imx_sc_ipc *imx_sc_irq_ipc_handle; static struct
> > +work_struct imx_sc_irq_work; static
> > +ATOMIC_NOTIFIER_HEAD(imx_scu_irq_notifier_chain);
> > +
> > +int imx_scu_irq_register_notifier(struct notifier_block *nb) {
> > +	return atomic_notifier_chain_register(
> > +		&imx_scu_irq_notifier_chain, nb);
> > +}
> > +EXPORT_SYMBOL(imx_scu_irq_register_notifier);
> > +
> > +int imx_scu_irq_unregister_notifier(struct notifier_block *nb) {
> > +	return atomic_notifier_chain_unregister(
> > +		&imx_scu_irq_notifier_chain, nb);
> > +}
> > +EXPORT_SYMBOL(imx_scu_irq_unregister_notifier);
> > +
> > +static int imx_scu_irq_notifier_call_chain(unsigned long status, u8
> > +*group) {
> > +	return atomic_notifier_call_chain(&imx_scu_irq_notifier_chain,
> > +		status, (void *)group);
> > +}
> > +
> > +static void imx_scu_irq_work_handler(struct work_struct *work) {
> > +	struct imx_sc_msg_irq_get_status msg;
> > +	struct imx_sc_rpc_msg *hdr = &msg.hdr;
> > +	u32 irq_status;
> > +	int ret;
> > +	u8 i;
> > +
> > +	for (i = 0; i < IMX_SC_IRQ_NUM_GROUP; i++) {
> > +		hdr->ver = IMX_SC_RPC_VERSION;
> > +		hdr->svc = IMX_SC_RPC_SVC_IRQ;
> > +		hdr->func = IMX_SC_IRQ_FUNC_STATUS;
> > +		hdr->size = 2;
> > +
> > +		msg.data.req.resource = mu_resource_id;
> > +		msg.data.req.group = i;
> > +
> > +		ret = imx_scu_call_rpc(imx_sc_irq_ipc_handle, &msg, true);
> > +		if (ret) {
> > +			pr_err("get irq group %d status failed, ret %d\n",
> > +			       i, ret);
> > +			return;
> > +		}
> > +
> > +		irq_status = msg.data.resp.status;
> > +		if (!irq_status)
> > +			continue;
> > +
> > +		imx_scu_irq_notifier_call_chain(irq_status, &i);
> > +	}
> > +}
> > +
> > +void imx_scu_irq_enable(u8 group, u32 mask, u8 enable) {
> 
> Why should this be a void return?
> 
> Besides that, a nitpick better rename to imx_scu_irq_group_enable to
> distinguish with the exist general irq enable.


Will add return value in V7 and rename it as well.

Anson.

> 
> Regards
> Dong Aisheng
> 
> > +	struct imx_sc_msg_irq_enable msg;
> > +	struct imx_sc_rpc_msg *hdr = &msg.hdr;
> > +	int ret;
> > +
> > +	hdr->ver = IMX_SC_RPC_VERSION;
> > +	hdr->svc = IMX_SC_RPC_SVC_IRQ;
> > +	hdr->func = IMX_SC_IRQ_FUNC_ENABLE;
> > +	hdr->size = 3;
> > +
> > +	msg.resource = mu_resource_id;
> > +	msg.group = group;
> > +	msg.mask = mask;
> > +	msg.enable = enable;
> > +
> > +	ret = imx_scu_call_rpc(imx_sc_irq_ipc_handle, &msg, true);
> > +	if (ret)
> > +		pr_err("enable irq failed, group %d, mask %d, ret %d\n",
> > +			group, mask, ret);
> > +}
> > +EXPORT_SYMBOL(imx_scu_irq_enable);
> > +
> > +static void imx_scu_irq_callback(struct mbox_client *c, void *msg) {
> > +	schedule_work(&imx_sc_irq_work);
> > +}
> > +
> > +int imx_scu_enable_general_irq_channel(struct device *dev) {
> > +	struct of_phandle_args spec;
> > +	struct mbox_client *cl;
> > +	struct mbox_chan *ch;
> > +	int ret = 0, i = 0;
> > +
> > +	ret = imx_scu_get_handle(&imx_sc_irq_ipc_handle);
> > +	if (ret)
> > +		return ret;
> > +
> > +	cl = devm_kzalloc(dev, sizeof(*cl), GFP_KERNEL);
> > +	if (!cl)
> > +		return -ENOMEM;
> > +
> > +	cl->dev = dev;
> > +	cl->rx_callback = imx_scu_irq_callback;
> > +
> > +	/* SCU general IRQ uses general interrupt channel 3 */
> > +	ch = mbox_request_channel_byname(cl, "gip3");
> > +	if (IS_ERR(ch)) {
> > +		ret = PTR_ERR(ch);
> > +		dev_err(dev, "failed to request mbox chan gip3, ret %d\n",
> ret);
> > +		devm_kfree(dev, cl);
> > +		return ret;
> > +	}
> > +
> > +	INIT_WORK(&imx_sc_irq_work, imx_scu_irq_work_handler);
> > +
> > +	if (!of_parse_phandle_with_args(dev->of_node, "mboxes",
> > +				       "#mbox-cells", 0, &spec))
> > +		i = of_alias_get_id(spec.np, "mu");
> > +
> > +	/* use mu1 as general mu irq channel if failed */
> > +	if (i < 0)
> > +		i = 1;
> > +
> > +	mu_resource_id = IMX_SC_R_MU_0A + i;
> > +
> > +	return ret;
> > +}
> > +EXPORT_SYMBOL(imx_scu_enable_general_irq_channel);
> > diff --git a/drivers/firmware/imx/imx-scu.c
> > b/drivers/firmware/imx/imx-scu.c index 2bb1a19..04a24a8 100644
> > --- a/drivers/firmware/imx/imx-scu.c
> > +++ b/drivers/firmware/imx/imx-scu.c
> > @@ -10,6 +10,7 @@
> >  #include <linux/err.h>
> >  #include <linux/firmware/imx/types.h>  #include
> > <linux/firmware/imx/ipc.h>
> > +#include <linux/firmware/imx/sci.h>
> >  #include <linux/interrupt.h>
> >  #include <linux/irq.h>
> >  #include <linux/kernel.h>
> > @@ -246,6 +247,11 @@ static int imx_scu_probe(struct platform_device
> > *pdev)
> >
> >  	imx_sc_ipc_handle = sc_ipc;
> >
> > +	ret = imx_scu_enable_general_irq_channel(dev);
> > +	if (ret)
> > +		dev_warn(dev,
> > +			"failed to enable general irq channel: %d\n", ret);
> > +
> >  	dev_info(dev, "NXP i.MX SCU Initialized\n");
> >
> >  	return devm_of_platform_populate(dev); diff --git
> > a/include/linux/firmware/imx/sci.h b/include/linux/firmware/imx/sci.h
> > index ebc5509..4100be7 100644
> > --- a/include/linux/firmware/imx/sci.h
> > +++ b/include/linux/firmware/imx/sci.h
> > @@ -15,4 +15,9 @@
> >
> >  #include <linux/firmware/imx/svc/misc.h>  #include
> > <linux/firmware/imx/svc/pm.h>
> > +
> > +int imx_scu_enable_general_irq_channel(struct device *dev); int
> > +imx_scu_irq_register_notifier(struct notifier_block *nb); int
> > +imx_scu_irq_unregister_notifier(struct notifier_block *nb); void
> > +imx_scu_irq_enable(u8 group, u32 mask, u8 enable);
> >  #endif /* _SC_SCI_H */
> > --
> > 2.7.4
diff mbox series

Patch

diff --git a/drivers/firmware/imx/Makefile b/drivers/firmware/imx/Makefile
index 1b2e15b..802c4ad 100644
--- a/drivers/firmware/imx/Makefile
+++ b/drivers/firmware/imx/Makefile
@@ -1,3 +1,3 @@ 
 # SPDX-License-Identifier: GPL-2.0
-obj-$(CONFIG_IMX_SCU)		+= imx-scu.o misc.o
+obj-$(CONFIG_IMX_SCU)		+= imx-scu.o misc.o imx-scu-irq.o
 obj-$(CONFIG_IMX_SCU_PD)	+= scu-pd.o
diff --git a/drivers/firmware/imx/imx-scu-irq.c b/drivers/firmware/imx/imx-scu-irq.c
new file mode 100644
index 0000000..4000c63
--- /dev/null
+++ b/drivers/firmware/imx/imx-scu-irq.c
@@ -0,0 +1,166 @@ 
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2019 NXP
+ *
+ * Implementation of the SCU IRQ functions using MU.
+ *
+ */
+
+#include <dt-bindings/firmware/imx/rsrc.h>
+#include <linux/firmware/imx/ipc.h>
+#include <linux/mailbox_client.h>
+
+#define IMX_SC_IRQ_FUNC_ENABLE	1
+#define IMX_SC_IRQ_FUNC_STATUS	2
+#define IMX_SC_IRQ_NUM_GROUP	4
+
+static u32 mu_resource_id;
+
+struct imx_sc_msg_irq_get_status {
+	struct imx_sc_rpc_msg hdr;
+	union {
+		struct {
+			u16 resource;
+			u8 group;
+			u8 reserved;
+		} __packed req;
+		struct {
+			u32 status;
+		} resp;
+	} data;
+};
+
+struct imx_sc_msg_irq_enable {
+	struct imx_sc_rpc_msg hdr;
+	u32 mask;
+	u16 resource;
+	u8 group;
+	u8 enable;
+} __packed;
+
+static struct imx_sc_ipc *imx_sc_irq_ipc_handle;
+static struct work_struct imx_sc_irq_work;
+static ATOMIC_NOTIFIER_HEAD(imx_scu_irq_notifier_chain);
+
+int imx_scu_irq_register_notifier(struct notifier_block *nb)
+{
+	return atomic_notifier_chain_register(
+		&imx_scu_irq_notifier_chain, nb);
+}
+EXPORT_SYMBOL(imx_scu_irq_register_notifier);
+
+int imx_scu_irq_unregister_notifier(struct notifier_block *nb)
+{
+	return atomic_notifier_chain_unregister(
+		&imx_scu_irq_notifier_chain, nb);
+}
+EXPORT_SYMBOL(imx_scu_irq_unregister_notifier);
+
+static int imx_scu_irq_notifier_call_chain(unsigned long status, u8 *group)
+{
+	return atomic_notifier_call_chain(&imx_scu_irq_notifier_chain,
+		status, (void *)group);
+}
+
+static void imx_scu_irq_work_handler(struct work_struct *work)
+{
+	struct imx_sc_msg_irq_get_status msg;
+	struct imx_sc_rpc_msg *hdr = &msg.hdr;
+	u32 irq_status;
+	int ret;
+	u8 i;
+
+	for (i = 0; i < IMX_SC_IRQ_NUM_GROUP; i++) {
+		hdr->ver = IMX_SC_RPC_VERSION;
+		hdr->svc = IMX_SC_RPC_SVC_IRQ;
+		hdr->func = IMX_SC_IRQ_FUNC_STATUS;
+		hdr->size = 2;
+
+		msg.data.req.resource = mu_resource_id;
+		msg.data.req.group = i;
+
+		ret = imx_scu_call_rpc(imx_sc_irq_ipc_handle, &msg, true);
+		if (ret) {
+			pr_err("get irq group %d status failed, ret %d\n",
+			       i, ret);
+			return;
+		}
+
+		irq_status = msg.data.resp.status;
+		if (!irq_status)
+			continue;
+
+		imx_scu_irq_notifier_call_chain(irq_status, &i);
+	}
+}
+
+void imx_scu_irq_enable(u8 group, u32 mask, u8 enable)
+{
+	struct imx_sc_msg_irq_enable msg;
+	struct imx_sc_rpc_msg *hdr = &msg.hdr;
+	int ret;
+
+	hdr->ver = IMX_SC_RPC_VERSION;
+	hdr->svc = IMX_SC_RPC_SVC_IRQ;
+	hdr->func = IMX_SC_IRQ_FUNC_ENABLE;
+	hdr->size = 3;
+
+	msg.resource = mu_resource_id;
+	msg.group = group;
+	msg.mask = mask;
+	msg.enable = enable;
+
+	ret = imx_scu_call_rpc(imx_sc_irq_ipc_handle, &msg, true);
+	if (ret)
+		pr_err("enable irq failed, group %d, mask %d, ret %d\n",
+			group, mask, ret);
+}
+EXPORT_SYMBOL(imx_scu_irq_enable);
+
+static void imx_scu_irq_callback(struct mbox_client *c, void *msg)
+{
+	schedule_work(&imx_sc_irq_work);
+}
+
+int imx_scu_enable_general_irq_channel(struct device *dev)
+{
+	struct of_phandle_args spec;
+	struct mbox_client *cl;
+	struct mbox_chan *ch;
+	int ret = 0, i = 0;
+
+	ret = imx_scu_get_handle(&imx_sc_irq_ipc_handle);
+	if (ret)
+		return ret;
+
+	cl = devm_kzalloc(dev, sizeof(*cl), GFP_KERNEL);
+	if (!cl)
+		return -ENOMEM;
+
+	cl->dev = dev;
+	cl->rx_callback = imx_scu_irq_callback;
+
+	/* SCU general IRQ uses general interrupt channel 3 */
+	ch = mbox_request_channel_byname(cl, "gip3");
+	if (IS_ERR(ch)) {
+		ret = PTR_ERR(ch);
+		dev_err(dev, "failed to request mbox chan gip3, ret %d\n", ret);
+		devm_kfree(dev, cl);
+		return ret;
+	}
+
+	INIT_WORK(&imx_sc_irq_work, imx_scu_irq_work_handler);
+
+	if (!of_parse_phandle_with_args(dev->of_node, "mboxes",
+				       "#mbox-cells", 0, &spec))
+		i = of_alias_get_id(spec.np, "mu");
+
+	/* use mu1 as general mu irq channel if failed */
+	if (i < 0)
+		i = 1;
+
+	mu_resource_id = IMX_SC_R_MU_0A + i;
+
+	return ret;
+}
+EXPORT_SYMBOL(imx_scu_enable_general_irq_channel);
diff --git a/drivers/firmware/imx/imx-scu.c b/drivers/firmware/imx/imx-scu.c
index 2bb1a19..04a24a8 100644
--- a/drivers/firmware/imx/imx-scu.c
+++ b/drivers/firmware/imx/imx-scu.c
@@ -10,6 +10,7 @@ 
 #include <linux/err.h>
 #include <linux/firmware/imx/types.h>
 #include <linux/firmware/imx/ipc.h>
+#include <linux/firmware/imx/sci.h>
 #include <linux/interrupt.h>
 #include <linux/irq.h>
 #include <linux/kernel.h>
@@ -246,6 +247,11 @@  static int imx_scu_probe(struct platform_device *pdev)
 
 	imx_sc_ipc_handle = sc_ipc;
 
+	ret = imx_scu_enable_general_irq_channel(dev);
+	if (ret)
+		dev_warn(dev,
+			"failed to enable general irq channel: %d\n", ret);
+
 	dev_info(dev, "NXP i.MX SCU Initialized\n");
 
 	return devm_of_platform_populate(dev);
diff --git a/include/linux/firmware/imx/sci.h b/include/linux/firmware/imx/sci.h
index ebc5509..4100be7 100644
--- a/include/linux/firmware/imx/sci.h
+++ b/include/linux/firmware/imx/sci.h
@@ -15,4 +15,9 @@ 
 
 #include <linux/firmware/imx/svc/misc.h>
 #include <linux/firmware/imx/svc/pm.h>
+
+int imx_scu_enable_general_irq_channel(struct device *dev);
+int imx_scu_irq_register_notifier(struct notifier_block *nb);
+int imx_scu_irq_unregister_notifier(struct notifier_block *nb);
+void imx_scu_irq_enable(u8 group, u32 mask, u8 enable);
 #endif /* _SC_SCI_H */