Merge branch irq/fsl-mu-msi into irq/irqchip-next

* irq/fsl-mu-msi:
  : .
  : Platform MSI controller driver for the IMX MU block
  :
  : Patches from Frank Li.
  : .
  dt-bindings: irqchip: Describe the IMX MU block as a MSI controller
  irqchip: Add IMX MU MSI controller driver
  irqchip: Allow extra fields to be passed to IRQCHIP_PLATFORM_DRIVER_END
  platform-msi: Export symbol platform_msi_create_irq_domain()

Signed-off-by: Marc Zyngier <maz@kernel.org>

Documentation/devicetree/bindings/interrupt-controller/fsl,mu-msi.yaml

@@ -0,0 +1,99 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/interrupt-controller/fsl,mu-msi.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Freescale/NXP i.MX Messaging Unit (MU) work as msi controller
+
+maintainers:
+  - Frank Li <Frank.Li@nxp.com>
+
+description: |
+  The Messaging Unit module enables two processors within the SoC to
+  communicate and coordinate by passing messages (e.g. data, status
+  and control) through the MU interface. The MU also provides the ability
+  for one processor (A side) to signal the other processor (B side) using
+  interrupts.
+
+  Because the MU manages the messaging between processors, the MU uses
+  different clocks (from each side of the different peripheral buses).
+  Therefore, the MU must synchronize the accesses from one side to the
+  other. The MU accomplishes synchronization using two sets of matching
+  registers (Processor A-side, Processor B-side).
+
+  MU can work as msi interrupt controller to do doorbell
+
+allOf:
+  - $ref: /schemas/interrupt-controller/msi-controller.yaml#
+
+properties:
+  compatible:
+    enum:
+      - fsl,imx6sx-mu-msi
+      - fsl,imx7ulp-mu-msi
+      - fsl,imx8ulp-mu-msi
+      - fsl,imx8ulp-mu-msi-s4
+
+  reg:
+    items:
+      - description: a side register base address
+      - description: b side register base address
+
+  reg-names:
+    items:
+      - const: processor-a-side
+      - const: processor-b-side
+
+  interrupts:
+    description: a side interrupt number.
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+  power-domains:
+    items:
+      - description: a side power domain
+      - description: b side power domain
+
+  power-domain-names:
+    items:
+      - const: processor-a-side
+      - const: processor-b-side
+
+  interrupt-controller: true
+
+  msi-controller: true
+
+  "#msi-cells":
+    const: 0
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - interrupt-controller
+  - msi-controller
+  - "#msi-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    #include <dt-bindings/firmware/imx/rsrc.h>
+
+    msi-controller@5d270000 {
+        compatible = "fsl,imx6sx-mu-msi";
+        msi-controller;
+        #msi-cells = <0>;
+        interrupt-controller;
+        reg = <0x5d270000 0x10000>,     /* A side */
+              <0x5d300000 0x10000>;     /* B side */
+        reg-names = "processor-a-side", "processor-b-side";
+        interrupts = <GIC_SPI 191 IRQ_TYPE_LEVEL_HIGH>;
+        power-domains = <&pd IMX_SC_R_MU_12A>,
+                        <&pd IMX_SC_R_MU_12B>;
+        power-domain-names = "processor-a-side", "processor-b-side";
+    };

drivers/base/platform-msi.c

@@ -138,6 +138,7 @@ struct irq_domain *platform_msi_create_irq_domain(struct fwnode_handle *fwnode,
 
 	return domain;
 }
+EXPORT_SYMBOL_GPL(platform_msi_create_irq_domain);
 
 static int platform_msi_alloc_priv_data(struct device *dev, unsigned int nvec,
 					irq_write_msi_msg_t write_msi_msg)

drivers/irqchip/Kconfig

@@ -481,6 +481,20 @@ config IMX_INTMUX
 	help
 	  Support for the i.MX INTMUX interrupt multiplexer.
 
+config IMX_MU_MSI
+	tristate "i.MX MU used as MSI controller"
+	depends on OF && HAS_IOMEM
+	default m if ARCH_MXC
+	select IRQ_DOMAIN
+	select IRQ_DOMAIN_HIERARCHY
+	select GENERIC_MSI_IRQ_DOMAIN
+	help
+	  Provide a driver for the MU block used as a CPU-to-CPU MSI
+	  controller. This requires a specially crafted DT to make use
+	  of this driver.
+
+	  If unsure, say N
+
 config LS1X_IRQ
 	bool "Loongson-1 Interrupt Controller"
 	depends on MACH_LOONGSON32

drivers/irqchip/Makefile

@@ -99,6 +99,7 @@ obj-$(CONFIG_RISCV_INTC)		+= irq-riscv-intc.o
 obj-$(CONFIG_SIFIVE_PLIC)		+= irq-sifive-plic.o
 obj-$(CONFIG_IMX_IRQSTEER)		+= irq-imx-irqsteer.o
 obj-$(CONFIG_IMX_INTMUX)		+= irq-imx-intmux.o
+obj-$(CONFIG_IMX_MU_MSI)		+= irq-imx-mu-msi.o
 obj-$(CONFIG_MADERA_IRQ)		+= irq-madera.o
 obj-$(CONFIG_LS1X_IRQ)			+= irq-ls1x.o
 obj-$(CONFIG_TI_SCI_INTR_IRQCHIP)	+= irq-ti-sci-intr.o