3 files changed, 175 insertions, 1 deletions

diff --git a/drivers/firmware/imx/Makefile b/drivers/firmware/imx/Makefile
index 1b2e15b3c9ca..802c4ad8e8f9 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 000000000000..043833ad3c1a
--- /dev/null
+++ b/drivers/firmware/imx/imx-scu-irq.c
@@ -0,0 +1,168 @@
+// 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);
+	}
+}
+
+int imx_scu_irq_group_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);
+
+	return ret;
+}
+EXPORT_SYMBOL(imx_scu_irq_group_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 2bb1a19c413f..04a24a863d6e 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);