[PATCH v2 0/3] Add Qualcomm IPCC driver support

[PATCH v2 0/3] Add Qualcomm IPCC driver support

[Manivannan Sadhasivam]

Hello,

This series adds mailbox driver support for Qualcomm Inter Processor
Communications Controller (IPCC) block found in MSM chipsets. This block
is used to route interrupts between modems, DSPs and APSS (Application
Processor Subsystem).

The driver is modeled as a mailbox+irqchip driver. The irqchip part helps
in receiving the interrupts from the IPCC clients such as modems, DSPs,
PCI-E etc... and forwards them to respective entities in APSS.
    
On the other hand, the mailbox part is used to send interrupts to the IPCC
clients from the entities of APSS.

This series is tested on SM8250-MTP board.

Thanks,
Mani

Changes in v2:

* Moved from soc/ to mailbox/
* Switched to static mbox channels
* Some misc cleanups

Manivannan Sadhasivam (3):
  dt-bindings: mailbox: Add devicetree binding for Qcom IPCC
  mailbox: Add support for Qualcomm IPCC
  MAINTAINERS: Add entry for Qualcomm IPCC driver

 .../bindings/mailbox/qcom-ipcc.yaml           |  77 +++++
 MAINTAINERS                                   |   8 +
 drivers/mailbox/Kconfig                       |  10 +
 drivers/mailbox/Makefile                      |   2 +
 drivers/mailbox/qcom-ipcc.c                   | 286 ++++++++++++++++++
 include/dt-bindings/mailbox/qcom-ipcc.h       |  33 ++
 6 files changed, 416 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mailbox/qcom-ipcc.yaml
 create mode 100644 drivers/mailbox/qcom-ipcc.c
 create mode 100644 include/dt-bindings/mailbox/qcom-ipcc.h

-- 
2.17.1

[PATCH v2 1/3] dt-bindings: mailbox: Add devicetree binding for Qcom IPCC

[Manivannan Sadhasivam]

Add devicetree YAML binding for Qualcomm Inter-Processor Communication
Controller (IPCC) block.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
 .../bindings/mailbox/qcom-ipcc.yaml           | 77 +++++++++++++++++++
 include/dt-bindings/mailbox/qcom-ipcc.h       | 33 ++++++++
 2 files changed, 110 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mailbox/qcom-ipcc.yaml
 create mode 100644 include/dt-bindings/mailbox/qcom-ipcc.h

diff --git a/Documentation/devicetree/bindings/mailbox/qcom-ipcc.yaml b/Documentation/devicetree/bindings/mailbox/qcom-ipcc.yaml
new file mode 100644
index 000000000000..62e7bc8ceb0b
--- /dev/null
+++ b/Documentation/devicetree/bindings/mailbox/qcom-ipcc.yaml
@@ -0,0 +1,77 @@
+# SPDX-License-Identifier: GPL-2.0 OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mailbox/qcom-ipcc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Qualcomm Technologies, Inc. Inter-Processor Communication Controller
+
+maintainers:
+  - Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
+
+description:
+  The Inter-Processor Communication Controller (IPCC) is a centralized hardware
+  to route interrupts across various subsystems. It involves a three-level
+  addressing scheme called protocol, client and signal. For example, consider an
+  entity on the Application Processor Subsystem (APSS) that wants to listen to
+  Modem's interrupts via Shared Memory Point to Point (SMP2P) interface. In such
+  a case, the client would be Modem (client-id is 2) and the signal would be
+  SMP2P (signal-id is 2). The SMP2P itself falls under the Multiprocessor (MPROC)
+  protocol (protocol-id is 0). Refer include/dt-bindings/mailbox/qcom-ipcc.h
+  for the list of such IDs.
+
+properties:
+  compatible:
+    const: "qcom,ipcc"
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  interrupt-controller: true
+
+  "#interrupt-cells":
+    const: 3
+    description:
+      The first cell is the client-id, the second cell is the signal-id and the
+      third cell is the interrupt type.
+
+  "#mbox-cells":
+    const: 2
+    description:
+      The first cell is the client-id, and the second cell is the signal-id.
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - interrupt-controller
+  - "#interrupt-cells"
+  - "#mbox-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+        #include <dt-bindings/interrupt-controller/arm-gic.h>
+        #include <dt-bindings/mailbox/qcom-ipcc.h>
+
+        mailbox: qcom,ipcc@408000 {
+                compatible = "qcom,ipcc";
+                reg = <0x408000 0x1000>;
+                interrupts = <GIC_SPI 229 IRQ_TYPE_LEVEL_HIGH>;
+                interrupt-controller;
+                #interrupt-cells = <3>;
+                #mbox-cells = <2>;
+        };
+
+        smp2p-modem {
+                compatible = "qcom,smp2p";
+                interrupts-extended = <&ipcc_mproc IPCC_CLIENT_MPSS
+                                IPCC_MPROC_SIGNAL_SMP2P IRQ_TYPE_EDGE_RISING>;
+                mboxes = <&ipcc_mproc IPCC_CLIENT_MPSS IPCC_MPROC_SIGNAL_SMP2P>;
+
+                /* Other SMP2P fields */
+        };
diff --git a/include/dt-bindings/mailbox/qcom-ipcc.h b/include/dt-bindings/mailbox/qcom-ipcc.h
new file mode 100644
index 000000000000..b8c04f6df57c
--- /dev/null
+++ b/include/dt-bindings/mailbox/qcom-ipcc.h
@@ -0,0 +1,33 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (c) 2018-2020, The Linux Foundation. All rights reserved.
+ */
+
+#ifndef __DT_BINDINGS_MAILBOX_IPCC_H
+#define __DT_BINDINGS_MAILBOX_IPCC_H
+
+/* Signal IDs for MPROC protocol */
+#define IPCC_MPROC_SIGNAL_GLINK_QMP	0
+#define IPCC_MPROC_SIGNAL_SMP2P		2
+#define IPCC_MPROC_SIGNAL_PING		3
+
+/* Client IDs */
+#define IPCC_CLIENT_AOP			0
+#define IPCC_CLIENT_TZ			1
+#define IPCC_CLIENT_MPSS		2
+#define IPCC_CLIENT_LPASS		3
+#define IPCC_CLIENT_SLPI		4
+#define IPCC_CLIENT_SDC			5
+#define IPCC_CLIENT_CDSP		6
+#define IPCC_CLIENT_NPU			7
+#define IPCC_CLIENT_APSS		8
+#define IPCC_CLIENT_GPU			9
+#define IPCC_CLIENT_CVP			10
+#define IPCC_CLIENT_CAM			11
+#define IPCC_CLIENT_VPU			12
+#define IPCC_CLIENT_PCIE0		13
+#define IPCC_CLIENT_PCIE1		14
+#define IPCC_CLIENT_PCIE2		15
+#define IPCC_CLIENT_SPSS		16
+
+#endif
-- 
2.17.1

[PATCH v2 2/3] mailbox: Add support for Qualcomm IPCC

[Manivannan Sadhasivam]

Add support for the Inter-Processor Communication Controller (IPCC)
block from Qualcomm that coordinates the interrupts (inbound & outbound)
for Multiprocessor (MPROC), COMPUTE-Level0 (COMPUTE-L0) & COMPUTE-Level1
(COMPUTE-L1) protocols for the Application Processor Subsystem (APSS).

This driver is modeled as an irqchip+mailbox driver. The irqchip part
helps in receiving the interrupts from the IPCC clients such as modems,
DSPs, PCI-E etc... and forwards them to respective entities in APSS.

On the other hand, the mailbox part is used to send interrupts to the IPCC
clients from the entities of APSS.

Signed-off-by: Raghavendra Rao Ananta <rananta@codeaurora.org>
Signed-off-by: Venkata Narendra Kumar Gutta <vnkgutta@codeaurora.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
[mani: moved to mailbox, added static mbox channels and cleanups]
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
 drivers/mailbox/Kconfig     |  10 ++
 drivers/mailbox/Makefile    |   2 +
 drivers/mailbox/qcom-ipcc.c | 286 ++++++++++++++++++++++++++++++++++++
 3 files changed, 298 insertions(+)
 create mode 100644 drivers/mailbox/qcom-ipcc.c

diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig
index 5a577a6734cf..8e1ebdbf8eab 100644
--- a/drivers/mailbox/Kconfig
+++ b/drivers/mailbox/Kconfig
@@ -236,4 +236,14 @@ config SUN6I_MSGBOX
 	  various Allwinner SoCs. This mailbox is used for communication
 	  between the application CPUs and the power management coprocessor.
 
+config QCOM_IPCC
+	bool "Qualcomm Technologies, Inc. IPCC driver"
+	depends on ARCH_QCOM || COMPILE_TEST
+	help
+	  Qualcomm Technologies, Inc. Inter-Processor Communication Controller
+	  (IPCC) driver for MSM devices. The driver provides mailbox support for
+	  sending interrupts to the clients. On the other hand, the driver also
+	  acts as an interrupt controller for receiving interrupts from clients.
+	  Say Y here if you want to build this driver.
+
 endif
diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile
index 2e4364ef5c47..20b66b2219aa 100644
--- a/drivers/mailbox/Makefile
+++ b/drivers/mailbox/Makefile
@@ -50,3 +50,5 @@ obj-$(CONFIG_MTK_CMDQ_MBOX)	+= mtk-cmdq-mailbox.o
 obj-$(CONFIG_ZYNQMP_IPI_MBOX)	+= zynqmp-ipi-mailbox.o
 
 obj-$(CONFIG_SUN6I_MSGBOX)	+= sun6i-msgbox.o
+
+obj-$(CONFIG_QCOM_IPCC)		+= qcom-ipcc.o
diff --git a/drivers/mailbox/qcom-ipcc.c b/drivers/mailbox/qcom-ipcc.c
new file mode 100644
index 000000000000..2d13c72944c6
--- /dev/null
+++ b/drivers/mailbox/qcom-ipcc.c
@@ -0,0 +1,286 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2018-2020, The Linux Foundation. All rights reserved.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/mailbox_controller.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+#include <dt-bindings/mailbox/qcom-ipcc.h>
+
+#define IPCC_MBOX_MAX_CHAN		48
+
+/* IPCC Register offsets */
+#define IPCC_REG_SEND_ID		0x0c
+#define IPCC_REG_RECV_ID		0x10
+#define IPCC_REG_RECV_SIGNAL_ENABLE	0x14
+#define IPCC_REG_RECV_SIGNAL_DISABLE	0x18
+#define IPCC_REG_RECV_SIGNAL_CLEAR	0x1c
+#define IPCC_REG_CLIENT_CLEAR		0x38
+
+#define IPCC_SIGNAL_ID_MASK		GENMASK(15, 0)
+#define IPCC_CLIENT_ID_MASK		GENMASK(31, 16)
+
+#define IPCC_NO_PENDING_IRQ		GENMASK(31, 0)
+
+/**
+ * struct qcom_ipcc_chan_info - Per-mailbox-channel info
+ * @client_id:	The client-id to which the interrupt has to be triggered
+ * @signal_id:	The signal-id to which the interrupt has to be triggered
+ */
+struct qcom_ipcc_chan_info {
+	u16 client_id;
+	u16 signal_id;
+};
+
+/**
+ * struct qcom_ipcc - Holder for the mailbox driver
+ * @dev:		Device associated with this instance
+ * @base:		Base address of the IPCC frame associated to APSS
+ * @irq_domain:		The irq_domain associated with this instance
+ * @chan:		The mailbox channels array
+ * @mchan:		The per-mailbox channel info array
+ * @mbox:		The mailbox controller
+ * @irq:		Summary irq
+ */
+struct qcom_ipcc {
+	struct device *dev;
+	void __iomem *base;
+	struct irq_domain *irq_domain;
+	struct mbox_chan chan[IPCC_MBOX_MAX_CHAN];
+	struct qcom_ipcc_chan_info mchan[IPCC_MBOX_MAX_CHAN];
+	struct mbox_controller mbox;
+	int irq;
+};
+
+static inline struct qcom_ipcc *to_qcom_ipcc(struct mbox_controller *mbox)
+{
+	return container_of(mbox, struct qcom_ipcc, mbox);
+}
+
+static inline u32 qcom_ipcc_get_hwirq(u16 client_id, u16 signal_id)
+{
+	return FIELD_PREP(IPCC_CLIENT_ID_MASK, client_id) |
+	       FIELD_PREP(IPCC_SIGNAL_ID_MASK, signal_id);
+}
+
+static irqreturn_t qcom_ipcc_irq_fn(int irq, void *data)
+{
+	struct qcom_ipcc *ipcc = data;
+	u32 hwirq;
+	int virq;
+
+	for (;;) {
+		hwirq = readl(ipcc->base + IPCC_REG_RECV_ID);
+		if (hwirq == IPCC_NO_PENDING_IRQ)
+			break;
+
+		virq = irq_find_mapping(ipcc->irq_domain, hwirq);
+		writel(hwirq, ipcc->base + IPCC_REG_RECV_SIGNAL_CLEAR);
+		generic_handle_irq(virq);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static void qcom_ipcc_mask_irq(struct irq_data *irqd)
+{
+	struct qcom_ipcc *ipcc = irq_data_get_irq_chip_data(irqd);
+	irq_hw_number_t hwirq = irqd_to_hwirq(irqd);
+
+	writel(hwirq, ipcc->base + IPCC_REG_RECV_SIGNAL_DISABLE);
+}
+
+static void qcom_ipcc_unmask_irq(struct irq_data *irqd)
+{
+	struct qcom_ipcc *ipcc = irq_data_get_irq_chip_data(irqd);
+	irq_hw_number_t hwirq = irqd_to_hwirq(irqd);
+
+	writel(hwirq, ipcc->base + IPCC_REG_RECV_SIGNAL_ENABLE);
+}
+
+static struct irq_chip qcom_ipcc_irq_chip = {
+	.name = "ipcc",
+	.irq_mask = qcom_ipcc_mask_irq,
+	.irq_unmask = qcom_ipcc_unmask_irq,
+	.flags = IRQCHIP_SKIP_SET_WAKE,
+};
+
+static int qcom_ipcc_domain_map(struct irq_domain *d, unsigned int irq,
+				irq_hw_number_t hw)
+{
+	struct qcom_ipcc *ipcc = d->host_data;
+
+	irq_set_chip_and_handler(irq, &qcom_ipcc_irq_chip, handle_level_irq);
+	irq_set_chip_data(irq, ipcc);
+	irq_set_noprobe(irq);
+
+	return 0;
+}
+
+static int qcom_ipcc_domain_xlate(struct irq_domain *d,
+				  struct device_node *node, const u32 *intspec,
+				  unsigned int intsize,
+				  unsigned long *out_hwirq,
+				  unsigned int *out_type)
+{
+	if (intsize != 3)
+		return -EINVAL;
+
+	*out_hwirq = qcom_ipcc_get_hwirq(intspec[0], intspec[1]);
+	*out_type = intspec[2] & IRQ_TYPE_SENSE_MASK;
+
+	return 0;
+}
+
+static const struct irq_domain_ops qcom_ipcc_irq_ops = {
+	.map = qcom_ipcc_domain_map,
+	.xlate = qcom_ipcc_domain_xlate,
+};
+
+static int qcom_ipcc_mbox_send_data(struct mbox_chan *chan, void *data)
+{
+	struct qcom_ipcc *ipcc = to_qcom_ipcc(chan->mbox);
+	struct qcom_ipcc_chan_info *mchan = chan->con_priv;
+	u32 hwirq;
+
+	hwirq = qcom_ipcc_get_hwirq(mchan->client_id, mchan->signal_id);
+	writel(hwirq, ipcc->base + IPCC_REG_SEND_ID);
+
+	return 0;
+}
+
+static struct mbox_chan *qcom_ipcc_mbox_xlate(struct mbox_controller *mbox,
+					const struct of_phandle_args *ph)
+{
+	struct qcom_ipcc *ipcc = to_qcom_ipcc(mbox);
+	struct qcom_ipcc_chan_info *mchan;
+	struct mbox_chan *chan;
+	unsigned int i;
+
+	if (ph->args_count != 2)
+		return ERR_PTR(-EINVAL);
+
+	for (i = 0; i < IPCC_MBOX_MAX_CHAN; i++) {
+		chan = &ipcc->chan[i];
+		if (!chan->con_priv) {
+			mchan = &ipcc->mchan[i];
+			mchan->client_id = ph->args[0];
+			mchan->signal_id = ph->args[1];
+			chan->con_priv = mchan;
+			break;
+		}
+
+		chan = NULL;
+	}
+
+	return chan ?: ERR_PTR(-EBUSY);
+}
+
+static const struct mbox_chan_ops ipcc_mbox_chan_ops = {
+	.send_data = qcom_ipcc_mbox_send_data,
+};
+
+static int qcom_ipcc_setup_mbox(struct qcom_ipcc *ipcc)
+{
+	struct mbox_controller *mbox;
+	struct device *dev = ipcc->dev;
+
+	mbox = &ipcc->mbox;
+	mbox->dev = dev;
+	mbox->num_chans = IPCC_MBOX_MAX_CHAN;
+	mbox->chans = ipcc->chan;
+	mbox->ops = &ipcc_mbox_chan_ops;
+	mbox->of_xlate = qcom_ipcc_mbox_xlate;
+	mbox->txdone_irq = false;
+	mbox->txdone_poll = false;
+
+	return devm_mbox_controller_register(dev, mbox);
+}
+
+static int qcom_ipcc_probe(struct platform_device *pdev)
+{
+	struct qcom_ipcc *ipcc;
+	int ret;
+
+	ipcc = devm_kzalloc(&pdev->dev, sizeof(*ipcc), GFP_KERNEL);
+	if (!ipcc)
+		return -ENOMEM;
+
+	ipcc->dev = &pdev->dev;
+
+	ipcc->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(ipcc->base))
+		return PTR_ERR(ipcc->base);
+
+	ipcc->irq = platform_get_irq(pdev, 0);
+	if (ipcc->irq < 0)
+		return ipcc->irq;
+
+	ipcc->irq_domain = irq_domain_add_tree(pdev->dev.of_node,
+					       &qcom_ipcc_irq_ops, ipcc);
+	if (!ipcc->irq_domain)
+		return -ENOMEM;
+
+	ret = qcom_ipcc_setup_mbox(ipcc);
+	if (ret)
+		goto err_mbox;
+
+	ret = devm_request_irq(&pdev->dev, ipcc->irq, qcom_ipcc_irq_fn,
+			       IRQF_TRIGGER_HIGH, "ipcc", ipcc);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Failed to register the irq: %d\n", ret);
+		goto err_mbox;
+	}
+
+	enable_irq_wake(ipcc->irq);
+	platform_set_drvdata(pdev, ipcc);
+
+	return 0;
+
+err_mbox:
+	irq_domain_remove(ipcc->irq_domain);
+
+	return ret;
+}
+
+static int qcom_ipcc_remove(struct platform_device *pdev)
+{
+	struct qcom_ipcc *ipcc = platform_get_drvdata(pdev);
+
+	disable_irq_wake(ipcc->irq);
+	irq_domain_remove(ipcc->irq_domain);
+
+	return 0;
+}
+
+static const struct of_device_id qcom_ipcc_of_match[] = {
+	{ .compatible = "qcom,ipcc"},
+	{}
+};
+MODULE_DEVICE_TABLE(of, qcom_ipcc_of_match);
+
+static struct platform_driver qcom_ipcc_driver = {
+	.probe = qcom_ipcc_probe,
+	.remove = qcom_ipcc_remove,
+	.driver = {
+		.name = "qcom-ipcc",
+		.of_match_table = qcom_ipcc_of_match,
+	},
+};
+
+static int __init qcom_ipcc_init(void)
+{
+	return platform_driver_register(&qcom_ipcc_driver);
+}
+arch_initcall(qcom_ipcc_init);
+
+MODULE_AUTHOR("Venkata Narendra Kumar Gutta <vnkgutta@codeaurora.org>");
+MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>");
+MODULE_DESCRIPTION("Qualcomm Technologies, Inc. IPCC driver");
+MODULE_LICENSE("GPL v2");
-- 
2.17.1

[PATCH v2 3/3] MAINTAINERS: Add entry for Qualcomm IPCC driver

[Manivannan Sadhasivam]

Add MAINTAINERS entry for Qualcomm IPCC driver and its binding.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
 MAINTAINERS | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index e64e5db31497..cc2fb991cc0d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -14013,6 +14013,14 @@ L:	linux-arm-msm@vger.kernel.org
 S:	Maintained
 F:	drivers/iommu/qcom_iommu.c
 
+QUALCOMM IPCC MAILBOX DRIVER
+M:	Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
+L:	linux-arm-msm@vger.kernel.org
+S:	Supported
+F:	Documentation/devicetree/bindings/mailbox/qcom-ipcc.yaml
+F:	drivers/mailbox/qcom-ipcc.c
+F:	include/dt-bindings/mailbox/qcom-ipcc.h
+
 QUALCOMM RMNET DRIVER
 M:	Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
 M:	Sean Tranchetti <stranche@codeaurora.org>
-- 
2.17.1

Re: [PATCH v2 1/3] dt-bindings: mailbox: Add devicetree binding for Qcom IPCC

[Bjorn Andersson]

On Fri 08 May 11:27 PDT 2020, Manivannan Sadhasivam wrote:

> Add devicetree YAML binding for Qualcomm Inter-Processor Communication
> Controller (IPCC) block.
> 

Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>

Regards,
Bjorn

> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> ---
>  .../bindings/mailbox/qcom-ipcc.yaml           | 77 +++++++++++++++++++
>  include/dt-bindings/mailbox/qcom-ipcc.h       | 33 ++++++++
>  2 files changed, 110 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/mailbox/qcom-ipcc.yaml
>  create mode 100644 include/dt-bindings/mailbox/qcom-ipcc.h
> 
> diff --git a/Documentation/devicetree/bindings/mailbox/qcom-ipcc.yaml b/Documentation/devicetree/bindings/mailbox/qcom-ipcc.yaml
> new file mode 100644
> index 000000000000..62e7bc8ceb0b
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mailbox/qcom-ipcc.yaml
> @@ -0,0 +1,77 @@
> +# SPDX-License-Identifier: GPL-2.0 OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/mailbox/qcom-ipcc.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Qualcomm Technologies, Inc. Inter-Processor Communication Controller
> +
> +maintainers:
> +  - Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> +
> +description:
> +  The Inter-Processor Communication Controller (IPCC) is a centralized hardware
> +  to route interrupts across various subsystems. It involves a three-level
> +  addressing scheme called protocol, client and signal. For example, consider an
> +  entity on the Application Processor Subsystem (APSS) that wants to listen to
> +  Modem's interrupts via Shared Memory Point to Point (SMP2P) interface. In such
> +  a case, the client would be Modem (client-id is 2) and the signal would be
> +  SMP2P (signal-id is 2). The SMP2P itself falls under the Multiprocessor (MPROC)
> +  protocol (protocol-id is 0). Refer include/dt-bindings/mailbox/qcom-ipcc.h
> +  for the list of such IDs.
> +
> +properties:
> +  compatible:
> +    const: "qcom,ipcc"
> +
> +  reg:
> +    maxItems: 1
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  interrupt-controller: true
> +
> +  "#interrupt-cells":
> +    const: 3
> +    description:
> +      The first cell is the client-id, the second cell is the signal-id and the
> +      third cell is the interrupt type.
> +
> +  "#mbox-cells":
> +    const: 2
> +    description:
> +      The first cell is the client-id, and the second cell is the signal-id.
> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +  - interrupt-controller
> +  - "#interrupt-cells"
> +  - "#mbox-cells"
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +        #include <dt-bindings/interrupt-controller/arm-gic.h>
> +        #include <dt-bindings/mailbox/qcom-ipcc.h>
> +
> +        mailbox: qcom,ipcc@408000 {
> +                compatible = "qcom,ipcc";
> +                reg = <0x408000 0x1000>;
> +                interrupts = <GIC_SPI 229 IRQ_TYPE_LEVEL_HIGH>;
> +                interrupt-controller;
> +                #interrupt-cells = <3>;
> +                #mbox-cells = <2>;
> +        };
> +
> +        smp2p-modem {
> +                compatible = "qcom,smp2p";
> +                interrupts-extended = <&ipcc_mproc IPCC_CLIENT_MPSS
> +                                IPCC_MPROC_SIGNAL_SMP2P IRQ_TYPE_EDGE_RISING>;
> +                mboxes = <&ipcc_mproc IPCC_CLIENT_MPSS IPCC_MPROC_SIGNAL_SMP2P>;
> +
> +                /* Other SMP2P fields */
> +        };
> diff --git a/include/dt-bindings/mailbox/qcom-ipcc.h b/include/dt-bindings/mailbox/qcom-ipcc.h
> new file mode 100644
> index 000000000000..b8c04f6df57c
> --- /dev/null
> +++ b/include/dt-bindings/mailbox/qcom-ipcc.h
> @@ -0,0 +1,33 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * Copyright (c) 2018-2020, The Linux Foundation. All rights reserved.
> + */
> +
> +#ifndef __DT_BINDINGS_MAILBOX_IPCC_H
> +#define __DT_BINDINGS_MAILBOX_IPCC_H
> +
> +/* Signal IDs for MPROC protocol */
> +#define IPCC_MPROC_SIGNAL_GLINK_QMP	0
> +#define IPCC_MPROC_SIGNAL_SMP2P		2
> +#define IPCC_MPROC_SIGNAL_PING		3
> +
> +/* Client IDs */
> +#define IPCC_CLIENT_AOP			0
> +#define IPCC_CLIENT_TZ			1
> +#define IPCC_CLIENT_MPSS		2
> +#define IPCC_CLIENT_LPASS		3
> +#define IPCC_CLIENT_SLPI		4
> +#define IPCC_CLIENT_SDC			5
> +#define IPCC_CLIENT_CDSP		6
> +#define IPCC_CLIENT_NPU			7
> +#define IPCC_CLIENT_APSS		8
> +#define IPCC_CLIENT_GPU			9
> +#define IPCC_CLIENT_CVP			10
> +#define IPCC_CLIENT_CAM			11
> +#define IPCC_CLIENT_VPU			12
> +#define IPCC_CLIENT_PCIE0		13
> +#define IPCC_CLIENT_PCIE1		14
> +#define IPCC_CLIENT_PCIE2		15
> +#define IPCC_CLIENT_SPSS		16
> +
> +#endif
> -- 
> 2.17.1
> 

Re: [PATCH v2 2/3] mailbox: Add support for Qualcomm IPCC

[Bjorn Andersson]

On Fri 08 May 11:27 PDT 2020, Manivannan Sadhasivam wrote:

> Add support for the Inter-Processor Communication Controller (IPCC)
> block from Qualcomm that coordinates the interrupts (inbound & outbound)
> for Multiprocessor (MPROC), COMPUTE-Level0 (COMPUTE-L0) & COMPUTE-Level1
> (COMPUTE-L1) protocols for the Application Processor Subsystem (APSS).
> 
> This driver is modeled as an irqchip+mailbox driver. The irqchip part
> helps in receiving the interrupts from the IPCC clients such as modems,
> DSPs, PCI-E etc... and forwards them to respective entities in APSS.
> 
> On the other hand, the mailbox part is used to send interrupts to the IPCC
> clients from the entities of APSS.
> 
> Signed-off-by: Raghavendra Rao Ananta <rananta@codeaurora.org>
> Signed-off-by: Venkata Narendra Kumar Gutta <vnkgutta@codeaurora.org>
> Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
> [mani: moved to mailbox, added static mbox channels and cleanups]
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

This looks nice now!

Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>

Regards,
Bjorn

> ---
>  drivers/mailbox/Kconfig     |  10 ++
>  drivers/mailbox/Makefile    |   2 +
>  drivers/mailbox/qcom-ipcc.c | 286 ++++++++++++++++++++++++++++++++++++
>  3 files changed, 298 insertions(+)
>  create mode 100644 drivers/mailbox/qcom-ipcc.c
> 
> diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig
> index 5a577a6734cf..8e1ebdbf8eab 100644
> --- a/drivers/mailbox/Kconfig
> +++ b/drivers/mailbox/Kconfig
> @@ -236,4 +236,14 @@ config SUN6I_MSGBOX
>  	  various Allwinner SoCs. This mailbox is used for communication
>  	  between the application CPUs and the power management coprocessor.
>  
> +config QCOM_IPCC
> +	bool "Qualcomm Technologies, Inc. IPCC driver"
> +	depends on ARCH_QCOM || COMPILE_TEST
> +	help
> +	  Qualcomm Technologies, Inc. Inter-Processor Communication Controller
> +	  (IPCC) driver for MSM devices. The driver provides mailbox support for
> +	  sending interrupts to the clients. On the other hand, the driver also
> +	  acts as an interrupt controller for receiving interrupts from clients.
> +	  Say Y here if you want to build this driver.
> +
>  endif
> diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile
> index 2e4364ef5c47..20b66b2219aa 100644
> --- a/drivers/mailbox/Makefile
> +++ b/drivers/mailbox/Makefile
> @@ -50,3 +50,5 @@ obj-$(CONFIG_MTK_CMDQ_MBOX)	+= mtk-cmdq-mailbox.o
>  obj-$(CONFIG_ZYNQMP_IPI_MBOX)	+= zynqmp-ipi-mailbox.o
>  
>  obj-$(CONFIG_SUN6I_MSGBOX)	+= sun6i-msgbox.o
> +
> +obj-$(CONFIG_QCOM_IPCC)		+= qcom-ipcc.o
> diff --git a/drivers/mailbox/qcom-ipcc.c b/drivers/mailbox/qcom-ipcc.c
> new file mode 100644
> index 000000000000..2d13c72944c6
> --- /dev/null
> +++ b/drivers/mailbox/qcom-ipcc.c
> @@ -0,0 +1,286 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (c) 2018-2020, The Linux Foundation. All rights reserved.
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/interrupt.h>
> +#include <linux/irq.h>
> +#include <linux/irqdomain.h>
> +#include <linux/mailbox_controller.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +
> +#include <dt-bindings/mailbox/qcom-ipcc.h>
> +
> +#define IPCC_MBOX_MAX_CHAN		48
> +
> +/* IPCC Register offsets */
> +#define IPCC_REG_SEND_ID		0x0c
> +#define IPCC_REG_RECV_ID		0x10
> +#define IPCC_REG_RECV_SIGNAL_ENABLE	0x14
> +#define IPCC_REG_RECV_SIGNAL_DISABLE	0x18
> +#define IPCC_REG_RECV_SIGNAL_CLEAR	0x1c
> +#define IPCC_REG_CLIENT_CLEAR		0x38
> +
> +#define IPCC_SIGNAL_ID_MASK		GENMASK(15, 0)
> +#define IPCC_CLIENT_ID_MASK		GENMASK(31, 16)
> +
> +#define IPCC_NO_PENDING_IRQ		GENMASK(31, 0)
> +
> +/**
> + * struct qcom_ipcc_chan_info - Per-mailbox-channel info
> + * @client_id:	The client-id to which the interrupt has to be triggered
> + * @signal_id:	The signal-id to which the interrupt has to be triggered
> + */
> +struct qcom_ipcc_chan_info {
> +	u16 client_id;
> +	u16 signal_id;
> +};
> +
> +/**
> + * struct qcom_ipcc - Holder for the mailbox driver
> + * @dev:		Device associated with this instance
> + * @base:		Base address of the IPCC frame associated to APSS
> + * @irq_domain:		The irq_domain associated with this instance
> + * @chan:		The mailbox channels array
> + * @mchan:		The per-mailbox channel info array
> + * @mbox:		The mailbox controller
> + * @irq:		Summary irq
> + */
> +struct qcom_ipcc {
> +	struct device *dev;
> +	void __iomem *base;
> +	struct irq_domain *irq_domain;
> +	struct mbox_chan chan[IPCC_MBOX_MAX_CHAN];
> +	struct qcom_ipcc_chan_info mchan[IPCC_MBOX_MAX_CHAN];
> +	struct mbox_controller mbox;
> +	int irq;
> +};
> +
> +static inline struct qcom_ipcc *to_qcom_ipcc(struct mbox_controller *mbox)
> +{
> +	return container_of(mbox, struct qcom_ipcc, mbox);
> +}
> +
> +static inline u32 qcom_ipcc_get_hwirq(u16 client_id, u16 signal_id)
> +{
> +	return FIELD_PREP(IPCC_CLIENT_ID_MASK, client_id) |
> +	       FIELD_PREP(IPCC_SIGNAL_ID_MASK, signal_id);
> +}
> +
> +static irqreturn_t qcom_ipcc_irq_fn(int irq, void *data)
> +{
> +	struct qcom_ipcc *ipcc = data;
> +	u32 hwirq;
> +	int virq;
> +
> +	for (;;) {
> +		hwirq = readl(ipcc->base + IPCC_REG_RECV_ID);
> +		if (hwirq == IPCC_NO_PENDING_IRQ)
> +			break;
> +
> +		virq = irq_find_mapping(ipcc->irq_domain, hwirq);
> +		writel(hwirq, ipcc->base + IPCC_REG_RECV_SIGNAL_CLEAR);
> +		generic_handle_irq(virq);
> +	}
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static void qcom_ipcc_mask_irq(struct irq_data *irqd)
> +{
> +	struct qcom_ipcc *ipcc = irq_data_get_irq_chip_data(irqd);
> +	irq_hw_number_t hwirq = irqd_to_hwirq(irqd);
> +
> +	writel(hwirq, ipcc->base + IPCC_REG_RECV_SIGNAL_DISABLE);
> +}
> +
> +static void qcom_ipcc_unmask_irq(struct irq_data *irqd)
> +{
> +	struct qcom_ipcc *ipcc = irq_data_get_irq_chip_data(irqd);
> +	irq_hw_number_t hwirq = irqd_to_hwirq(irqd);
> +
> +	writel(hwirq, ipcc->base + IPCC_REG_RECV_SIGNAL_ENABLE);
> +}
> +
> +static struct irq_chip qcom_ipcc_irq_chip = {
> +	.name = "ipcc",
> +	.irq_mask = qcom_ipcc_mask_irq,
> +	.irq_unmask = qcom_ipcc_unmask_irq,
> +	.flags = IRQCHIP_SKIP_SET_WAKE,
> +};
> +
> +static int qcom_ipcc_domain_map(struct irq_domain *d, unsigned int irq,
> +				irq_hw_number_t hw)
> +{
> +	struct qcom_ipcc *ipcc = d->host_data;
> +
> +	irq_set_chip_and_handler(irq, &qcom_ipcc_irq_chip, handle_level_irq);
> +	irq_set_chip_data(irq, ipcc);
> +	irq_set_noprobe(irq);
> +
> +	return 0;
> +}
> +
> +static int qcom_ipcc_domain_xlate(struct irq_domain *d,
> +				  struct device_node *node, const u32 *intspec,
> +				  unsigned int intsize,
> +				  unsigned long *out_hwirq,
> +				  unsigned int *out_type)
> +{
> +	if (intsize != 3)
> +		return -EINVAL;
> +
> +	*out_hwirq = qcom_ipcc_get_hwirq(intspec[0], intspec[1]);
> +	*out_type = intspec[2] & IRQ_TYPE_SENSE_MASK;
> +
> +	return 0;
> +}
> +
> +static const struct irq_domain_ops qcom_ipcc_irq_ops = {
> +	.map = qcom_ipcc_domain_map,
> +	.xlate = qcom_ipcc_domain_xlate,
> +};
> +
> +static int qcom_ipcc_mbox_send_data(struct mbox_chan *chan, void *data)
> +{
> +	struct qcom_ipcc *ipcc = to_qcom_ipcc(chan->mbox);
> +	struct qcom_ipcc_chan_info *mchan = chan->con_priv;
> +	u32 hwirq;
> +
> +	hwirq = qcom_ipcc_get_hwirq(mchan->client_id, mchan->signal_id);
> +	writel(hwirq, ipcc->base + IPCC_REG_SEND_ID);
> +
> +	return 0;
> +}
> +
> +static struct mbox_chan *qcom_ipcc_mbox_xlate(struct mbox_controller *mbox,
> +					const struct of_phandle_args *ph)
> +{
> +	struct qcom_ipcc *ipcc = to_qcom_ipcc(mbox);
> +	struct qcom_ipcc_chan_info *mchan;
> +	struct mbox_chan *chan;
> +	unsigned int i;
> +
> +	if (ph->args_count != 2)
> +		return ERR_PTR(-EINVAL);
> +
> +	for (i = 0; i < IPCC_MBOX_MAX_CHAN; i++) {
> +		chan = &ipcc->chan[i];
> +		if (!chan->con_priv) {
> +			mchan = &ipcc->mchan[i];
> +			mchan->client_id = ph->args[0];
> +			mchan->signal_id = ph->args[1];
> +			chan->con_priv = mchan;
> +			break;
> +		}
> +
> +		chan = NULL;
> +	}
> +
> +	return chan ?: ERR_PTR(-EBUSY);
> +}
> +
> +static const struct mbox_chan_ops ipcc_mbox_chan_ops = {
> +	.send_data = qcom_ipcc_mbox_send_data,
> +};
> +
> +static int qcom_ipcc_setup_mbox(struct qcom_ipcc *ipcc)
> +{
> +	struct mbox_controller *mbox;
> +	struct device *dev = ipcc->dev;
> +
> +	mbox = &ipcc->mbox;
> +	mbox->dev = dev;
> +	mbox->num_chans = IPCC_MBOX_MAX_CHAN;
> +	mbox->chans = ipcc->chan;
> +	mbox->ops = &ipcc_mbox_chan_ops;
> +	mbox->of_xlate = qcom_ipcc_mbox_xlate;
> +	mbox->txdone_irq = false;
> +	mbox->txdone_poll = false;
> +
> +	return devm_mbox_controller_register(dev, mbox);
> +}
> +
> +static int qcom_ipcc_probe(struct platform_device *pdev)
> +{
> +	struct qcom_ipcc *ipcc;
> +	int ret;
> +
> +	ipcc = devm_kzalloc(&pdev->dev, sizeof(*ipcc), GFP_KERNEL);
> +	if (!ipcc)
> +		return -ENOMEM;
> +
> +	ipcc->dev = &pdev->dev;
> +
> +	ipcc->base = devm_platform_ioremap_resource(pdev, 0);
> +	if (IS_ERR(ipcc->base))
> +		return PTR_ERR(ipcc->base);
> +
> +	ipcc->irq = platform_get_irq(pdev, 0);
> +	if (ipcc->irq < 0)
> +		return ipcc->irq;
> +
> +	ipcc->irq_domain = irq_domain_add_tree(pdev->dev.of_node,
> +					       &qcom_ipcc_irq_ops, ipcc);
> +	if (!ipcc->irq_domain)
> +		return -ENOMEM;
> +
> +	ret = qcom_ipcc_setup_mbox(ipcc);
> +	if (ret)
> +		goto err_mbox;
> +
> +	ret = devm_request_irq(&pdev->dev, ipcc->irq, qcom_ipcc_irq_fn,
> +			       IRQF_TRIGGER_HIGH, "ipcc", ipcc);
> +	if (ret < 0) {
> +		dev_err(&pdev->dev, "Failed to register the irq: %d\n", ret);
> +		goto err_mbox;
> +	}
> +
> +	enable_irq_wake(ipcc->irq);
> +	platform_set_drvdata(pdev, ipcc);
> +
> +	return 0;
> +
> +err_mbox:
> +	irq_domain_remove(ipcc->irq_domain);
> +
> +	return ret;
> +}
> +
> +static int qcom_ipcc_remove(struct platform_device *pdev)
> +{
> +	struct qcom_ipcc *ipcc = platform_get_drvdata(pdev);
> +
> +	disable_irq_wake(ipcc->irq);
> +	irq_domain_remove(ipcc->irq_domain);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id qcom_ipcc_of_match[] = {
> +	{ .compatible = "qcom,ipcc"},
> +	{}
> +};
> +MODULE_DEVICE_TABLE(of, qcom_ipcc_of_match);
> +
> +static struct platform_driver qcom_ipcc_driver = {
> +	.probe = qcom_ipcc_probe,
> +	.remove = qcom_ipcc_remove,
> +	.driver = {
> +		.name = "qcom-ipcc",
> +		.of_match_table = qcom_ipcc_of_match,
> +	},
> +};
> +
> +static int __init qcom_ipcc_init(void)
> +{
> +	return platform_driver_register(&qcom_ipcc_driver);
> +}
> +arch_initcall(qcom_ipcc_init);
> +
> +MODULE_AUTHOR("Venkata Narendra Kumar Gutta <vnkgutta@codeaurora.org>");
> +MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>");
> +MODULE_DESCRIPTION("Qualcomm Technologies, Inc. IPCC driver");
> +MODULE_LICENSE("GPL v2");
> -- 
> 2.17.1
> 

Re: [PATCH v2 3/3] MAINTAINERS: Add entry for Qualcomm IPCC driver

[Bjorn Andersson]

On Fri 08 May 11:27 PDT 2020, Manivannan Sadhasivam wrote:

> Add MAINTAINERS entry for Qualcomm IPCC driver and its binding.
> 

Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>

Regards,
Bjorn

> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> ---
>  MAINTAINERS | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index e64e5db31497..cc2fb991cc0d 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -14013,6 +14013,14 @@ L:	linux-arm-msm@vger.kernel.org
>  S:	Maintained
>  F:	drivers/iommu/qcom_iommu.c
>  
> +QUALCOMM IPCC MAILBOX DRIVER
> +M:	Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> +L:	linux-arm-msm@vger.kernel.org
> +S:	Supported
> +F:	Documentation/devicetree/bindings/mailbox/qcom-ipcc.yaml
> +F:	drivers/mailbox/qcom-ipcc.c
> +F:	include/dt-bindings/mailbox/qcom-ipcc.h
> +
>  QUALCOMM RMNET DRIVER
>  M:	Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
>  M:	Sean Tranchetti <stranche@codeaurora.org>
> -- 
> 2.17.1
> 

Re: [PATCH v2 1/3] dt-bindings: mailbox: Add devicetree binding for Qcom IPCC

[Rob Herring]

On Fri, May 08, 2020 at 11:57:01PM +0530, Manivannan Sadhasivam wrote:
> Add devicetree YAML binding for Qualcomm Inter-Processor Communication
> Controller (IPCC) block.
> 
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> ---
>  .../bindings/mailbox/qcom-ipcc.yaml           | 77 +++++++++++++++++++
>  include/dt-bindings/mailbox/qcom-ipcc.h       | 33 ++++++++
>  2 files changed, 110 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/mailbox/qcom-ipcc.yaml
>  create mode 100644 include/dt-bindings/mailbox/qcom-ipcc.h
> 
> diff --git a/Documentation/devicetree/bindings/mailbox/qcom-ipcc.yaml b/Documentation/devicetree/bindings/mailbox/qcom-ipcc.yaml
> new file mode 100644
> index 000000000000..62e7bc8ceb0b
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mailbox/qcom-ipcc.yaml
> @@ -0,0 +1,77 @@
> +# SPDX-License-Identifier: GPL-2.0 OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/mailbox/qcom-ipcc.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Qualcomm Technologies, Inc. Inter-Processor Communication Controller
> +
> +maintainers:
> +  - Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> +
> +description:
> +  The Inter-Processor Communication Controller (IPCC) is a centralized hardware
> +  to route interrupts across various subsystems. It involves a three-level
> +  addressing scheme called protocol, client and signal. For example, consider an
> +  entity on the Application Processor Subsystem (APSS) that wants to listen to
> +  Modem's interrupts via Shared Memory Point to Point (SMP2P) interface. In such
> +  a case, the client would be Modem (client-id is 2) and the signal would be
> +  SMP2P (signal-id is 2). The SMP2P itself falls under the Multiprocessor (MPROC)
> +  protocol (protocol-id is 0). Refer include/dt-bindings/mailbox/qcom-ipcc.h
> +  for the list of such IDs.
> +
> +properties:
> +  compatible:
> +    const: "qcom,ipcc"

Need SoC specific compatible(s).

No need for quotes.

> +
> +  reg:
> +    maxItems: 1
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  interrupt-controller: true
> +
> +  "#interrupt-cells":
> +    const: 3
> +    description:
> +      The first cell is the client-id, the second cell is the signal-id and the
> +      third cell is the interrupt type.
> +
> +  "#mbox-cells":
> +    const: 2
> +    description:
> +      The first cell is the client-id, and the second cell is the signal-id.
> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +  - interrupt-controller
> +  - "#interrupt-cells"
> +  - "#mbox-cells"
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +        #include <dt-bindings/interrupt-controller/arm-gic.h>
> +        #include <dt-bindings/mailbox/qcom-ipcc.h>
> +
> +        mailbox: qcom,ipcc@408000 {

mailbox@408000

> +                compatible = "qcom,ipcc";
> +                reg = <0x408000 0x1000>;
> +                interrupts = <GIC_SPI 229 IRQ_TYPE_LEVEL_HIGH>;
> +                interrupt-controller;
> +                #interrupt-cells = <3>;
> +                #mbox-cells = <2>;
> +        };
> +
> +        smp2p-modem {
> +                compatible = "qcom,smp2p";
> +                interrupts-extended = <&ipcc_mproc IPCC_CLIENT_MPSS
> +                                IPCC_MPROC_SIGNAL_SMP2P IRQ_TYPE_EDGE_RISING>;
> +                mboxes = <&ipcc_mproc IPCC_CLIENT_MPSS IPCC_MPROC_SIGNAL_SMP2P>;
> +
> +                /* Other SMP2P fields */
> +        };
> diff --git a/include/dt-bindings/mailbox/qcom-ipcc.h b/include/dt-bindings/mailbox/qcom-ipcc.h
> new file mode 100644
> index 000000000000..b8c04f6df57c
> --- /dev/null
> +++ b/include/dt-bindings/mailbox/qcom-ipcc.h
> @@ -0,0 +1,33 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */

Dual license please. I'm pretty sure your employer has an opinion on 
this.

> +/*
> + * Copyright (c) 2018-2020, The Linux Foundation. All rights reserved.
> + */
> +
> +#ifndef __DT_BINDINGS_MAILBOX_IPCC_H
> +#define __DT_BINDINGS_MAILBOX_IPCC_H
> +
> +/* Signal IDs for MPROC protocol */
> +#define IPCC_MPROC_SIGNAL_GLINK_QMP	0
> +#define IPCC_MPROC_SIGNAL_SMP2P		2
> +#define IPCC_MPROC_SIGNAL_PING		3
> +
> +/* Client IDs */
> +#define IPCC_CLIENT_AOP			0
> +#define IPCC_CLIENT_TZ			1
> +#define IPCC_CLIENT_MPSS		2
> +#define IPCC_CLIENT_LPASS		3
> +#define IPCC_CLIENT_SLPI		4
> +#define IPCC_CLIENT_SDC			5
> +#define IPCC_CLIENT_CDSP		6
> +#define IPCC_CLIENT_NPU			7
> +#define IPCC_CLIENT_APSS		8
> +#define IPCC_CLIENT_GPU			9
> +#define IPCC_CLIENT_CVP			10
> +#define IPCC_CLIENT_CAM			11
> +#define IPCC_CLIENT_VPU			12
> +#define IPCC_CLIENT_PCIE0		13
> +#define IPCC_CLIENT_PCIE1		14
> +#define IPCC_CLIENT_PCIE2		15
> +#define IPCC_CLIENT_SPSS		16
> +
> +#endif
> -- 
> 2.17.1
>