Merge tag 'stm32-bus-firewall-for-7.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/atorgue/stm32 into soc/drivers

STM32 Firewall bus for v7.1, round 1

Highlights:
----------
Stm32 SoCs embed debug peripherals such as Coresight. These peripherals
can monitor the activity of the cores. Because of that, they can be
used only if some features in the debug configuration are enabled.
Else, errors or firewall exceptions can be observed. Similarly to
the ETZPC(on stm32mp1x platforms) or the RIFSC(on stm32mp2x platforms),
debug-related peripherals access can be assessed at bus level to
prevent these issues from happening.

The debug configuration can only be accessed by the secure world.
That means that a service must be implemented in the secure world for
the kernel to check the firewall configuration. On OpenSTLinux, it is
done through a Debug access PTA in OP-TEE [1].
To represent the debug peripherals present on a dedicated debug bus,
create a debug bus node in the device tree and the associated driver
that will interact with this PTA.

Plus some fixes.

* tag 'stm32-bus-firewall-for-7.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/atorgue/stm32:
  pinctrl: stm32: add firewall checks before probing the HDP driver
  drivers: bus: add the stm32 debug bus driver
  bus: stm32_firewall: add stm32_firewall_get_grant_all_access() API
  bus: stm32_firewall: allow check on different firewall controllers
  dt-bindings: bus: document the stm32 debug bus
  dt-bindings: pinctrl: document access-controllers property for stm32 HDP
  dt-bindings: document access-controllers property for coresight peripherals
  bus: rifsc: fix RIF configuration check for peripherals
  bus: rifsc: Replace snprintf("%s") with strscpy
  bus: stm32_firewall: Simplify with scoped for each OF child loop
  bus: firewall: move stm32_firewall header file in include folder

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

8 files changed, 100 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/arm/arm,coresight-cti.yaml b/Documentation/devicetree/bindings/arm/arm,coresight-cti.yaml
index 2a91670ccb8c..949444aba1f8 100644
--- a/Documentation/devicetree/bindings/arm/arm,coresight-cti.yaml
+++ b/Documentation/devicetree/bindings/arm/arm,coresight-cti.yaml
@@ -128,6 +128,9 @@ properties:
   "#address-cells":
     const: 1
 
+  access-controllers:
+    maxItems: 1
+
 patternProperties:
   '^trig-conns@([0-9]+)$':
     type: object
diff --git a/Documentation/devicetree/bindings/arm/arm,coresight-dynamic-funnel.yaml b/Documentation/devicetree/bindings/arm/arm,coresight-dynamic-funnel.yaml
index b74db15e5f8a..b0693cd46d27 100644
--- a/Documentation/devicetree/bindings/arm/arm,coresight-dynamic-funnel.yaml
+++ b/Documentation/devicetree/bindings/arm/arm,coresight-dynamic-funnel.yaml
@@ -78,6 +78,9 @@ properties:
         description: Output connection to CoreSight Trace bus
         $ref: /schemas/graph.yaml#/properties/port
 
+  access-controllers:
+    maxItems: 1
+
 required:
   - compatible
   - reg
diff --git a/Documentation/devicetree/bindings/arm/arm,coresight-etm.yaml b/Documentation/devicetree/bindings/arm/arm,coresight-etm.yaml
index 71f2e1ed27e5..10ebbbeadf93 100644
--- a/Documentation/devicetree/bindings/arm/arm,coresight-etm.yaml
+++ b/Documentation/devicetree/bindings/arm/arm,coresight-etm.yaml
@@ -118,6 +118,9 @@ properties:
         description: Output connection from the ETM to CoreSight Trace bus.
         $ref: /schemas/graph.yaml#/properties/port
 
+  access-controllers:
+    maxItems: 1
+
 required:
   - compatible
   - clocks
diff --git a/Documentation/devicetree/bindings/arm/arm,coresight-stm.yaml b/Documentation/devicetree/bindings/arm/arm,coresight-stm.yaml
index 378380c3f5aa..f243e76f597f 100644
--- a/Documentation/devicetree/bindings/arm/arm,coresight-stm.yaml
+++ b/Documentation/devicetree/bindings/arm/arm,coresight-stm.yaml
@@ -73,6 +73,9 @@ properties:
         description: Output connection to the CoreSight Trace bus.
         $ref: /schemas/graph.yaml#/properties/port
 
+  access-controllers:
+    maxItems: 1
+
 required:
   - compatible
   - reg
diff --git a/Documentation/devicetree/bindings/arm/arm,coresight-tmc.yaml b/Documentation/devicetree/bindings/arm/arm,coresight-tmc.yaml
index 96dd5b5f771a..9dc096698c65 100644
--- a/Documentation/devicetree/bindings/arm/arm,coresight-tmc.yaml
+++ b/Documentation/devicetree/bindings/arm/arm,coresight-tmc.yaml
@@ -128,6 +128,9 @@ properties:
       - const: tracedata
       - const: metadata
 
+  access-controllers:
+    maxItems: 1
+
 required:
   - compatible
   - reg
diff --git a/Documentation/devicetree/bindings/arm/arm,coresight-tpiu.yaml b/Documentation/devicetree/bindings/arm/arm,coresight-tpiu.yaml
index a207f6899e67..29bbc3961fdf 100644
--- a/Documentation/devicetree/bindings/arm/arm,coresight-tpiu.yaml
+++ b/Documentation/devicetree/bindings/arm/arm,coresight-tpiu.yaml
@@ -70,6 +70,9 @@ properties:
         description: Input connection from the CoreSight Trace bus.
         $ref: /schemas/graph.yaml#/properties/port
 
+  access-controllers:
+    maxItems: 1
+
 required:
   - compatible
   - reg
diff --git a/Documentation/devicetree/bindings/bus/st,stm32mp131-dbg-bus.yaml b/Documentation/devicetree/bindings/bus/st,stm32mp131-dbg-bus.yaml
new file mode 100644
index 000000000000..6c74433efbe3
--- /dev/null
+++ b/Documentation/devicetree/bindings/bus/st,stm32mp131-dbg-bus.yaml
@@ -0,0 +1,76 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/bus/st,stm32mp131-dbg-bus.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: STM32 Coresight bus
+
+maintainers:
+  - Gatien Chevallier <gatien.chevallier@foss.st.com>
+
+description:
+  The STM32 debug bus is in charge of checking the debug configuration
+  of the platform before probing the peripheral drivers that rely on the debug
+  domain.
+
+properties:
+  compatible:
+    items:
+      - enum:
+          - st,stm32mp131-dbg-bus
+          - st,stm32mp151-dbg-bus
+
+  "#address-cells":
+    const: 1
+
+  "#size-cells":
+    const: 1
+
+  ranges:
+    minItems: 1
+    maxItems: 2
+
+  "#access-controller-cells":
+    const: 1
+    description:
+      Contains the debug profile necessary to access the peripheral.
+
+patternProperties:
+  "@[0-9a-f]+$":
+    description: Debug related peripherals
+    type: object
+
+    additionalProperties: true
+
+    required:
+      - access-controllers
+
+required:
+  - "#access-controller-cells"
+  - "#address-cells"
+  - "#size-cells"
+  - compatible
+  - ranges
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/stm32mp1-clks.h>
+
+    dbg_bus: bus@50080000 {
+      compatible = "st,stm32mp131-dbg-bus";
+      #address-cells = <1>;
+      #size-cells = <1>;
+      #access-controller-cells = <1>;
+      ranges = <0x50080000 0x50080000 0x3f80000>;
+
+      cti@50094000 {
+        compatible = "arm,coresight-cti", "arm,primecell";
+        reg = <0x50094000 0x1000>;
+        clocks = <&rcc CK_DBG>;
+        clock-names = "apb_pclk";
+        access-controllers = <&dbg_bus 0>;
+      };
+    };
diff --git a/Documentation/devicetree/bindings/pinctrl/st,stm32-hdp.yaml b/Documentation/devicetree/bindings/pinctrl/st,stm32-hdp.yaml
index 845b6b7b7552..8f8b4b68aaa3 100644
--- a/Documentation/devicetree/bindings/pinctrl/st,stm32-hdp.yaml
+++ b/Documentation/devicetree/bindings/pinctrl/st,stm32-hdp.yaml
@@ -27,6 +27,12 @@ properties:
   clocks:
     maxItems: 1
 
+  access-controllers:
+    minItems: 1
+    items:
+      - description: debug configuration access controller
+      - description: access controller that manages the HDP as a peripheral
+
 patternProperties:
   "^hdp[0-7]-pins$":
     type: object