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* [PATCH v5 0/6] Silvaco I3C master driver
@ 2021-01-21 10:18 Miquel Raynal
  2021-01-21 10:18 ` [PATCH v5 1/6] dt-bindings: i3c: Convert the bus description to yaml Miquel Raynal
                   ` (6 more replies)
  0 siblings, 7 replies; 10+ messages in thread
From: Miquel Raynal @ 2021-01-21 10:18 UTC (permalink / raw)
  To: Alexandre Belloni, linux-i3c, Rob Herring, devicetree
  Cc: Miquel Raynal, Rajeev Huralikoppi, Conor Culhane,
	Thomas Petazzoni, Nicolas Pitre

Hello,

Here is the addition of a driver for the Silvaco I3C master IP.

Changes in v5:
* Added Rob's R-by when relevant.
* Fixed the robots warnings by pushing a little bit forward the changes in the
  mipi-hci binding file.
* Fixed the I3C master node name regex.
* Removed the redundant $ref: entries when the hz suffix is used.
* Simplified a little bit the regexes defining the child nodes.
* Updated the reg propertie description to better describe each entry.

Changes in v4:
* Converted the I3C binding file to yaml schema (including a license
  change, as requested by checkpatch.pl)
* Included this schema to the MIPI HCI binding file.
* Updated the Silvaco binding following Rob's review.
* No changes in the driver at all.

Changes in v3:
* Fix the MAINTAINERS file.
* Fix the bindings (clocks description, size-cells, etc)
* Add Rob's Ack on one patch.
* Dropped unnecessary locks.
* Used a hardware feature to automatically NACK IBI's during regular
  data transfers.
* Stopped flushing FIFOs (not needed).
* Entirely reworked the IBI handling logic.
* Dropped the warning when a device does not advertise it's dynamic
  address during an IBI.
* Moved the IBI logic into the master's workqueue instead of a
  threaded handler.
* Added a svc_i3c_master_readb() helper.
* Used consistent bit definitions (BIT() vs. FIELD_GET()).

Changes in v2:
* Change the manufacturer name from svc to silvaco.

Miquel Raynal (6):
  dt-bindings: i3c: Convert the bus description to yaml
  dt-bindings: i3c: mipi-hci: Include the bus binding
  dt-bindings: Add vendor prefix for Silvaco
  dt-bindings: i3c: Describe Silvaco master binding
  i3c: master: svc: Add Silvaco I3C master driver
  MAINTAINERS: Add Silvaco I3C master

 Documentation/devicetree/bindings/i3c/i3c.txt |  140 --
 .../devicetree/bindings/i3c/i3c.yaml          |  179 ++
 .../devicetree/bindings/i3c/mipi-i3c-hci.yaml |    9 +-
 .../bindings/i3c/silvaco,i3c-master.yaml      |   60 +
 .../devicetree/bindings/vendor-prefixes.yaml  |    2 +
 MAINTAINERS                                   |    8 +
 drivers/i3c/master/Kconfig                    |    8 +
 drivers/i3c/master/Makefile                   |    1 +
 drivers/i3c/master/svc-i3c-master.c           | 1478 +++++++++++++++++
 9 files changed, 1743 insertions(+), 142 deletions(-)
 delete mode 100644 Documentation/devicetree/bindings/i3c/i3c.txt
 create mode 100644 Documentation/devicetree/bindings/i3c/i3c.yaml
 create mode 100644 Documentation/devicetree/bindings/i3c/silvaco,i3c-master.yaml
 create mode 100644 drivers/i3c/master/svc-i3c-master.c

-- 
2.20.1


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^ permalink raw reply	[flat|nested] 10+ messages in thread

* [PATCH v5 1/6] dt-bindings: i3c: Convert the bus description to yaml
  2021-01-21 10:18 [PATCH v5 0/6] Silvaco I3C master driver Miquel Raynal
@ 2021-01-21 10:18 ` Miquel Raynal
  2021-02-05 21:31   ` Rob Herring
  2021-01-21 10:18 ` [PATCH v5 2/6] dt-bindings: i3c: mipi-hci: Include the bus binding Miquel Raynal
                   ` (5 subsequent siblings)
  6 siblings, 1 reply; 10+ messages in thread
From: Miquel Raynal @ 2021-01-21 10:18 UTC (permalink / raw)
  To: Alexandre Belloni, linux-i3c, Rob Herring, devicetree
  Cc: Miquel Raynal, Rajeev Huralikoppi, Conor Culhane,
	Thomas Petazzoni, Nicolas Pitre

Attempting a conversion of the i3c.txt file to yaml schema with
minimal content changes.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
---
 Documentation/devicetree/bindings/i3c/i3c.txt | 140 --------------
 .../devicetree/bindings/i3c/i3c.yaml          | 179 ++++++++++++++++++
 2 files changed, 179 insertions(+), 140 deletions(-)
 delete mode 100644 Documentation/devicetree/bindings/i3c/i3c.txt
 create mode 100644 Documentation/devicetree/bindings/i3c/i3c.yaml

diff --git a/Documentation/devicetree/bindings/i3c/i3c.txt b/Documentation/devicetree/bindings/i3c/i3c.txt
deleted file mode 100644
index 4ffe059f0fec..000000000000
--- a/Documentation/devicetree/bindings/i3c/i3c.txt
+++ /dev/null
@@ -1,140 +0,0 @@
-Generic device tree bindings for I3C busses
-===========================================
-
-This document describes generic bindings that should be used to describe I3C
-busses in a device tree.
-
-Required properties
--------------------
-
-- #address-cells  - should be <3>. Read more about addresses below.
-- #size-cells     - should be <0>.
-- compatible      - name of the I3C master controller driving the I3C bus
-
-For other required properties e.g. to describe register sets,
-clocks, etc. check the binding documentation of the specific driver.
-The node describing an I3C bus should be named i3c-master.
-
-Optional properties
--------------------
-
-These properties may not be supported by all I3C master drivers. Each I3C
-master bindings should specify which of them are supported.
-
-- i3c-scl-hz: frequency of the SCL signal used for I3C transfers.
-	      When undefined the core sets it to 12.5MHz.
-
-- i2c-scl-hz: frequency of the SCL signal used for I2C transfers.
-	      When undefined, the core looks at LVR (Legacy Virtual Register)
-	      values of I2C devices described in the device tree to determine
-	      the maximum I2C frequency.
-
-I2C devices
-===========
-
-Each I2C device connected to the bus should be described in a subnode. All
-properties described in Documentation/devicetree/bindings/i2c/i2c.txt are
-valid here, but several new properties have been added.
-
-New constraint on existing properties:
---------------------------------------
-- reg: contains 3 cells
-  + first cell : still encoding the I2C address. 10 bit addressing is not
-    supported. Devices with 10 bit address can't be properly passed through
-    DEFSLVS command.
-
-  + second cell: shall be 0
-
-  + third cell: shall encode the I3C LVR (Legacy Virtual Register)
-	bit[31:8]: unused/ignored
-	bit[7:5]: I2C device index. Possible values
-	* 0: I2C device has a 50 ns spike filter
-	* 1: I2C device does not have a 50 ns spike filter but supports high
-	     frequency on SCL
-	* 2: I2C device does not have a 50 ns spike filter and is not tolerant
-	     to high frequencies
-	* 3-7: reserved
-
-	bit[4]: tell whether the device operates in FM (Fast Mode) or FM+ mode
-	* 0: FM+ mode
-	* 1: FM mode
-
-	bit[3:0]: device type
-	* 0-15: reserved
-
-The I2C node unit-address should always match the first cell of the reg
-property: <device-type>@<i2c-address>.
-
-I3C devices
-===========
-
-All I3C devices are supposed to support DAA (Dynamic Address Assignment), and
-are thus discoverable. So, by default, I3C devices do not have to be described
-in the device tree.
-This being said, one might want to attach extra resources to these devices,
-and those resources may have to be described in the device tree, which in turn
-means we have to describe I3C devices.
-
-Another use case for describing an I3C device in the device tree is when this
-I3C device has a static I2C address and we want to assign it a specific I3C
-dynamic address before the DAA takes place (so that other devices on the bus
-can't take this dynamic address).
-
-The I3C device should be names <device-type>@<static-i2c-address>,<i3c-pid>,
-where device-type is describing the type of device connected on the bus
-(gpio-controller, sensor, ...).
-
-Required properties
--------------------
-- reg: contains 3 cells
-  + first cell : encodes the static I2C address. Should be 0 if the device does
-		 not have one (0 is not a valid I2C address).
-
-  + second and third cells: should encode the ProvisionalID. The second cell
-			    contains the manufacturer ID left-shifted by 1.
-			    The third cell contains ORing of the part ID
-			    left-shifted by 16, the instance ID left-shifted
-			    by 12 and the extra information. This encoding is
-			    following the PID definition provided by the I3C
-			    specification.
-
-Optional properties
--------------------
-- assigned-address: dynamic address to be assigned to this device. This
-		    property is only valid if the I3C device has a static
-		    address (first cell of the reg property != 0).
-
-
-Example:
-
-	i3c-master@d040000 {
-		compatible = "cdns,i3c-master";
-		clocks = <&coreclock>, <&i3csysclock>;
-		clock-names = "pclk", "sysclk";
-		interrupts = <3 0>;
-		reg = <0x0d040000 0x1000>;
-		#address-cells = <3>;
-		#size-cells = <0>;
-		i2c-scl-hz = <100000>;
-
-		/* I2C device. */
-		nunchuk: nunchuk@52 {
-			compatible = "nintendo,nunchuk";
-			reg = <0x52 0x0 0x10>;
-		};
-
-		/* I3C device with a static I2C address. */
-		thermal_sensor: sensor@68,39200144004 {
-			reg = <0x68 0x392 0x144004>;
-			assigned-address = <0xa>;
-		};
-
-		/*
-		 * I3C device without a static I2C address but requiring
-		 * resources described in the DT.
-		 */
-		sensor@0,39200154004 {
-			reg = <0x0 0x392 0x154004>;
-			clocks = <&clock_provider 0>;
-		};
-	};
diff --git a/Documentation/devicetree/bindings/i3c/i3c.yaml b/Documentation/devicetree/bindings/i3c/i3c.yaml
new file mode 100644
index 000000000000..52042aa44d19
--- /dev/null
+++ b/Documentation/devicetree/bindings/i3c/i3c.yaml
@@ -0,0 +1,179 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/i3c/i3c.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: I3C bus binding
+
+maintainers:
+  - Alexandre Belloni <alexandre.belloni@bootlin.com>
+  - Miquel Raynal <miquel.raynal@bootlin.com>
+
+description: |
+  I3C busses can be described with a node for the primary I3C controller device
+  and a set of child nodes for each I2C or I3C slave on the bus. Each of them
+  may, during the life of the bus, request mastership.
+
+properties:
+  $nodename:
+    pattern: "^i3c-master@[0-9a-f]+$"
+
+  "#address-cells":
+    const: 3
+    description: |
+      Each I2C device connected to the bus should be described in a subnode.
+
+      All I3C devices are supposed to support DAA (Dynamic Address Assignment),
+      and are thus discoverable. So, by default, I3C devices do not have to be
+      described in the device tree. This being said, one might want to attach
+      extra resources to these devices, and those resources may have to be
+      described in the device tree, which in turn means we have to describe
+      I3C devices.
+
+      Another use case for describing an I3C device in the device tree is when
+      this I3C device has a static I2C address and we want to assign it a
+      specific I3C dynamic address before the DAA takes place (so that other
+      devices on the bus can't take this dynamic address).
+
+  "#size-cells":
+    const: 0
+
+  i3c-scl-hz:
+    description: |
+      Frequency of the SCL signal used for I3C transfers. When undefined, the
+      default value should be 12.5MHz.
+
+      May not be supported by all controllers.
+
+  i2c-scl-hz:
+    description: |
+      Frequency of the SCL signal used for I2C transfers. When undefined, the
+      default should be to look at LVR (Legacy Virtual Register) values of
+      I2C devices described in the device tree to determine the maximum I2C
+      frequency.
+
+      May not be supported by all controllers.
+
+required:
+  - "#address-cells"
+  - "#size-cells"
+
+patternProperties:
+  "@[0-9a-f]+$":
+    type: object
+    description: |
+      I2C child, should be named: <device-type>@<i2c-address>
+
+      All properties described in Documentation/devicetree/bindings/i2c/i2c.txt
+      are valid here, except the reg property whose content is changed.
+
+    properties:
+      compatible:
+        description:
+          Compatible of the I2C device.
+
+      reg:
+        items:
+          - items:
+              - description: |
+                  I2C address. 10 bit addressing is not supported. Devices with
+                  10-bit address can't be properly passed through DEFSLVS
+                  command.
+                minimum: 0
+                maximum: 0x7f
+              - const: 0
+              - description: |
+                  Shall encode the I3C LVR (Legacy Virtual Register):
+                    bit[31:8]: unused/ignored
+                    bit[7:5]: I2C device index. Possible values:
+                      * 0: I2C device has a 50 ns spike filter
+                      * 1: I2C device does not have a 50 ns spike filter but
+                           supports high frequency on SCL
+                      * 2: I2C device does not have a 50 ns spike filter and is
+                           not tolerant to high frequencies
+                      * 3-7: reserved
+                    bit[4]: tell whether the device operates in FM (Fast Mode)
+                            or FM+ mode:
+                      * 0: FM+ mode
+                      * 1: FM mode
+                    bit[3:0]: device type
+                      * 0-15: reserved
+
+    required:
+      - compatible
+      - reg
+
+  "@[0-9a-f]+,[0-9a-f]+$":
+    type: object
+    description: |
+      I3C child, should be named: <device-type>@<static-i2c-address>,<i3c-pid>
+
+    properties:
+      reg:
+        items:
+          - items:
+              - description: |
+                  Encodes the static I2C address. Should be 0 if the device does
+                  not have one (0 is not a valid I2C address).
+                minimum: 0
+                maximum: 0x7f
+              - description: |
+                  First half of the Provisional ID (following the PID
+                  definition provided by the I3C specification).
+
+                  Contains the manufacturer ID left-shifted by 1.
+              - description: |
+                  Second half of the Provisional ID (following the PID
+                  definition provided by the I3C specification).
+
+                  Contains the ORing of the part ID left-shifted by 16,
+                  the instance ID left-shifted by 12 and extra information.
+
+      assigned-address:
+        $ref: /schemas/types.yaml#/definitions/uint32
+        minimum: 0x1
+        maximum: 0xff
+        description: |
+          Dynamic address to be assigned to this device. This property is only
+          valid if the I3C device has a static address (first cell of the reg
+          property != 0).
+
+    required:
+      - reg
+
+additionalProperties: true
+
+examples:
+  - |
+    i3c-master@d040000 {
+        compatible = "cdns,i3c-master";
+        clocks = <&coreclock>, <&i3csysclock>;
+        clock-names = "pclk", "sysclk";
+        interrupts = <3 0>;
+        reg = <0x0d040000 0x1000>;
+        #address-cells = <3>;
+        #size-cells = <0>;
+        i2c-scl-hz = <100000>;
+
+        /* I2C device. */
+        nunchuk: nunchuk@52 {
+            compatible = "nintendo,nunchuk";
+            reg = <0x52 0x0 0x10>;
+        };
+
+        /* I3C device with a static I2C address. */
+        thermal_sensor: sensor@68,39200144004 {
+            reg = <0x68 0x392 0x144004>;
+            assigned-address = <0xa>;
+        };
+
+        /*
+         * I3C device without a static I2C address but requiring
+         * resources described in the DT.
+         */
+        sensor@0,39200154004 {
+            reg = <0x0 0x392 0x154004>;
+            clocks = <&clock_provider 0>;
+        };
+    };
-- 
2.20.1


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^ permalink raw reply related	[flat|nested] 10+ messages in thread

* [PATCH v5 2/6] dt-bindings: i3c: mipi-hci: Include the bus binding
  2021-01-21 10:18 [PATCH v5 0/6] Silvaco I3C master driver Miquel Raynal
  2021-01-21 10:18 ` [PATCH v5 1/6] dt-bindings: i3c: Convert the bus description to yaml Miquel Raynal
@ 2021-01-21 10:18 ` Miquel Raynal
  2021-02-05 21:31   ` Rob Herring
  2021-01-21 10:18 ` [PATCH v5 3/6] dt-bindings: Add vendor prefix for Silvaco Miquel Raynal
                   ` (4 subsequent siblings)
  6 siblings, 1 reply; 10+ messages in thread
From: Miquel Raynal @ 2021-01-21 10:18 UTC (permalink / raw)
  To: Alexandre Belloni, linux-i3c, Rob Herring, devicetree
  Cc: Miquel Raynal, Rajeev Huralikoppi, Conor Culhane,
	Thomas Petazzoni, Nicolas Pitre

Update a little bit the content to match the bus binding, including:
- the node title should have been named after the description done
  in the historical i3c.txt file, ie: i3c-master@<address>
- child nodes should be accepted even though the drivers do not currently
  support it
- #address-cells and #size-cells are also mandatory and have specific
  values

Cc: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
---
 Documentation/devicetree/bindings/i3c/mipi-i3c-hci.yaml | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/i3c/mipi-i3c-hci.yaml b/Documentation/devicetree/bindings/i3c/mipi-i3c-hci.yaml
index 07a7b10163a3..04da001fc6ec 100644
--- a/Documentation/devicetree/bindings/i3c/mipi-i3c-hci.yaml
+++ b/Documentation/devicetree/bindings/i3c/mipi-i3c-hci.yaml
@@ -9,6 +9,9 @@ title: MIPI I3C HCI Device Tree Bindings
 maintainers:
   - Nicolas Pitre <npitre@baylibre.com>
 
+allOf:
+  - $ref: /schemas/i3c/i3c.yaml#
+
 description: |
   MIPI I3C Host Controller Interface
 
@@ -36,12 +39,14 @@ required:
   - reg
   - interrupts
 
-additionalProperties: false
+unevaluatedProperties: false
 
 examples:
   - |
-    i3c@a0000000 {
+    i3c-master@a0000000 {
       compatible = "mipi-i3c-hci";
       reg = <0xa0000000 0x2000>;
       interrupts = <89>;
+      #address-cells = <3>;
+      #size-cells = <0>;
     };
-- 
2.20.1


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^ permalink raw reply related	[flat|nested] 10+ messages in thread

* [PATCH v5 3/6] dt-bindings: Add vendor prefix for Silvaco
  2021-01-21 10:18 [PATCH v5 0/6] Silvaco I3C master driver Miquel Raynal
  2021-01-21 10:18 ` [PATCH v5 1/6] dt-bindings: i3c: Convert the bus description to yaml Miquel Raynal
  2021-01-21 10:18 ` [PATCH v5 2/6] dt-bindings: i3c: mipi-hci: Include the bus binding Miquel Raynal
@ 2021-01-21 10:18 ` Miquel Raynal
  2021-01-21 10:18 ` [PATCH v5 4/6] dt-bindings: i3c: Describe Silvaco master binding Miquel Raynal
                   ` (3 subsequent siblings)
  6 siblings, 0 replies; 10+ messages in thread
From: Miquel Raynal @ 2021-01-21 10:18 UTC (permalink / raw)
  To: Alexandre Belloni, linux-i3c, Rob Herring, devicetree
  Cc: Rob Herring, Rajeev Huralikoppi, Nicolas Pitre, Thomas Petazzoni,
	Miquel Raynal, Conor Culhane

Silvaco, Inc. is an EDA provider of software tools used for process
and device development and for analog/mixed-signal, power IC and
memory design [1].

[1] https://www.silvaco.com/company/profile/profile.html

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Rob Herring <robh@kernel.org>
---
 Documentation/devicetree/bindings/vendor-prefixes.yaml | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Documentation/devicetree/bindings/vendor-prefixes.yaml b/Documentation/devicetree/bindings/vendor-prefixes.yaml
index 041ae90b0d8f..df1b7971c07e 100644
--- a/Documentation/devicetree/bindings/vendor-prefixes.yaml
+++ b/Documentation/devicetree/bindings/vendor-prefixes.yaml
@@ -1075,6 +1075,8 @@ patternProperties:
     description: Shenzhen Sunchip Technology Co., Ltd
   "^SUNW,.*":
     description: Sun Microsystems, Inc
+  "^silvaco,.*":
+    description: Silvaco, Inc.
   "^swir,.*":
     description: Sierra Wireless
   "^syna,.*":
-- 
2.20.1


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^ permalink raw reply related	[flat|nested] 10+ messages in thread

* [PATCH v5 4/6] dt-bindings: i3c: Describe Silvaco master binding
  2021-01-21 10:18 [PATCH v5 0/6] Silvaco I3C master driver Miquel Raynal
                   ` (2 preceding siblings ...)
  2021-01-21 10:18 ` [PATCH v5 3/6] dt-bindings: Add vendor prefix for Silvaco Miquel Raynal
@ 2021-01-21 10:18 ` Miquel Raynal
  2021-01-21 10:18 ` [PATCH v5 5/6] i3c: master: svc: Add Silvaco I3C master driver Miquel Raynal
                   ` (2 subsequent siblings)
  6 siblings, 0 replies; 10+ messages in thread
From: Miquel Raynal @ 2021-01-21 10:18 UTC (permalink / raw)
  To: Alexandre Belloni, linux-i3c, Rob Herring, devicetree
  Cc: Rob Herring, Rajeev Huralikoppi, Nicolas Pitre, Thomas Petazzoni,
	Miquel Raynal, Conor Culhane

Silvaco provide a dual-role I3C master.

Description is rather simple: it needs a register mapping, three
clocks and an interrupt.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
---
 .../bindings/i3c/silvaco,i3c-master.yaml      | 60 +++++++++++++++++++
 1 file changed, 60 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/i3c/silvaco,i3c-master.yaml

diff --git a/Documentation/devicetree/bindings/i3c/silvaco,i3c-master.yaml b/Documentation/devicetree/bindings/i3c/silvaco,i3c-master.yaml
new file mode 100644
index 000000000000..adb5165505aa
--- /dev/null
+++ b/Documentation/devicetree/bindings/i3c/silvaco,i3c-master.yaml
@@ -0,0 +1,60 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/i3c/silvaco,i3c-master.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Silvaco I3C master
+
+maintainers:
+  - Conor Culhane <conor.culhane@silvaco.com>
+
+allOf:
+  - $ref: "i3c.yaml#"
+
+properties:
+  compatible:
+    const: silvaco,i3c-master-v1
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  clocks:
+    items:
+      - description: system clock
+      - description: bus clock
+      - description: other (slower) events clock
+
+  clock-names:
+    items:
+      - const: pclk
+      - const: fast_clk
+      - const: slow_clk
+
+  resets:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - clock-names
+  - clocks
+
+additionalProperties: true
+
+examples:
+  - |
+    i3c-master@a0000000 {
+        compatible = "silvaco,i3c-master";
+        clocks = <&zynqmp_clk 71>, <&fclk>, <&sclk>;
+        clock-names = "pclk", "fast_clk", "slow_clk";
+        interrupt-parent = <&gic>;
+        interrupts = <0 89 4>;
+        reg = <0xa0000000 0x1000>;
+        #address-cells = <3>;
+        #size-cells = <0>;
+    };
-- 
2.20.1


-- 
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^ permalink raw reply related	[flat|nested] 10+ messages in thread

* [PATCH v5 5/6] i3c: master: svc: Add Silvaco I3C master driver
  2021-01-21 10:18 [PATCH v5 0/6] Silvaco I3C master driver Miquel Raynal
                   ` (3 preceding siblings ...)
  2021-01-21 10:18 ` [PATCH v5 4/6] dt-bindings: i3c: Describe Silvaco master binding Miquel Raynal
@ 2021-01-21 10:18 ` Miquel Raynal
  2021-01-21 10:18 ` [PATCH v5 6/6] MAINTAINERS: Add Silvaco I3C master Miquel Raynal
  2021-02-05 23:44 ` [PATCH v5 0/6] Silvaco I3C master driver Alexandre Belloni
  6 siblings, 0 replies; 10+ messages in thread
From: Miquel Raynal @ 2021-01-21 10:18 UTC (permalink / raw)
  To: Alexandre Belloni, linux-i3c, Rob Herring, devicetree
  Cc: Miquel Raynal, Rajeev Huralikoppi, Conor Culhane,
	Thomas Petazzoni, Nicolas Pitre

Add support for Silvaco I3C dual-role IP. The master role is supported
in SDR mode only. I2C transfers have not been tested but are shared
because they are very close to the I3C transfers in terms of register
configuration.

The IBI processing follows this logic:
- When a slave advertizes an interrupt (SDA pulled low) an interrupt
  gets generated by the master. This time is unbounded and may be
  deferred.
- The IRQ handler itself does not process anything: it only queues a
  work that will be run in non-atomic context. This is needed because
  short wait periods must be experienced.
- The IBI job is divided in two parts: the first one is "critical" in
  the sense that it may not support getting interrupted. If this
  happens, after this first section the driver checks the master error
  register and depending on its content either flushes everything and
  errors out, or ends the processing (this second section may be
  interrupted).
- If the critical section got interrupted, the slave will
  automatically respin it's IBI request when it will be allowed to.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
---
 drivers/i3c/master/Kconfig          |    8 +
 drivers/i3c/master/Makefile         |    1 +
 drivers/i3c/master/svc-i3c-master.c | 1478 +++++++++++++++++++++++++++
 3 files changed, 1487 insertions(+)
 create mode 100644 drivers/i3c/master/svc-i3c-master.c

diff --git a/drivers/i3c/master/Kconfig b/drivers/i3c/master/Kconfig
index e68f15f4b4d0..eb6ac7aa307b 100644
--- a/drivers/i3c/master/Kconfig
+++ b/drivers/i3c/master/Kconfig
@@ -22,6 +22,14 @@ config DW_I3C_MASTER
 	  This driver can also be built as a module.  If so, the module
 	  will be called dw-i3c-master.
 
+config SVC_I3C_MASTER
+	tristate "Silvaco I3C Dual-Role Master driver"
+	depends on I3C
+	depends on HAS_IOMEM
+	depends on !(ALPHA || PARISC)
+	help
+	  Support for Silvaco I3C Dual-Role Master Controller.
+
 config MIPI_I3C_HCI
 	tristate "MIPI I3C Host Controller Interface driver (EXPERIMENTAL)"
 	depends on I3C
diff --git a/drivers/i3c/master/Makefile b/drivers/i3c/master/Makefile
index b892fd4cafad..b3fee0f690b2 100644
--- a/drivers/i3c/master/Makefile
+++ b/drivers/i3c/master/Makefile
@@ -1,4 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0-only
 obj-$(CONFIG_CDNS_I3C_MASTER)		+= i3c-master-cdns.o
 obj-$(CONFIG_DW_I3C_MASTER)		+= dw-i3c-master.o
+obj-$(CONFIG_SVC_I3C_MASTER)		+= svc-i3c-master.o
 obj-$(CONFIG_MIPI_I3C_HCI)		+= mipi-i3c-hci/
diff --git a/drivers/i3c/master/svc-i3c-master.c b/drivers/i3c/master/svc-i3c-master.c
new file mode 100644
index 000000000000..8d990696676e
--- /dev/null
+++ b/drivers/i3c/master/svc-i3c-master.c
@@ -0,0 +1,1478 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Silvaco dual-role I3C master driver
+ *
+ * Copyright (C) 2020 Silvaco
+ * Author: Miquel RAYNAL <miquel.raynal@bootlin.com>
+ * Based on a work from: Conor Culhane <conor.culhane@silvaco.com>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/completion.h>
+#include <linux/errno.h>
+#include <linux/i3c/master.h>
+#include <linux/interrupt.h>
+#include <linux/iopoll.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+
+/* Master Mode Registers */
+#define SVC_I3C_MCONFIG      0x000
+#define   SVC_I3C_MCONFIG_MASTER_EN BIT(0)
+#define   SVC_I3C_MCONFIG_DISTO(x) FIELD_PREP(BIT(3), (x))
+#define   SVC_I3C_MCONFIG_HKEEP(x) FIELD_PREP(GENMASK(5, 4), (x))
+#define   SVC_I3C_MCONFIG_ODSTOP(x) FIELD_PREP(BIT(6), (x))
+#define   SVC_I3C_MCONFIG_PPBAUD(x) FIELD_PREP(GENMASK(11, 8), (x))
+#define   SVC_I3C_MCONFIG_PPLOW(x) FIELD_PREP(GENMASK(15, 12), (x))
+#define   SVC_I3C_MCONFIG_ODBAUD(x) FIELD_PREP(GENMASK(23, 16), (x))
+#define   SVC_I3C_MCONFIG_ODHPP(x) FIELD_PREP(BIT(24), (x))
+#define   SVC_I3C_MCONFIG_SKEW(x) FIELD_PREP(GENMASK(27, 25), (x))
+#define   SVC_I3C_MCONFIG_I2CBAUD(x) FIELD_PREP(GENMASK(31, 28), (x))
+
+#define SVC_I3C_MCTRL        0x084
+#define   SVC_I3C_MCTRL_REQUEST_MASK GENMASK(2, 0)
+#define   SVC_I3C_MCTRL_REQUEST_NONE 0
+#define   SVC_I3C_MCTRL_REQUEST_START_ADDR 1
+#define   SVC_I3C_MCTRL_REQUEST_STOP 2
+#define   SVC_I3C_MCTRL_REQUEST_IBI_ACKNACK 3
+#define   SVC_I3C_MCTRL_REQUEST_PROC_DAA 4
+#define   SVC_I3C_MCTRL_REQUEST_AUTO_IBI 7
+#define   SVC_I3C_MCTRL_TYPE_I3C 0
+#define   SVC_I3C_MCTRL_TYPE_I2C BIT(4)
+#define   SVC_I3C_MCTRL_IBIRESP_AUTO 0
+#define   SVC_I3C_MCTRL_IBIRESP_ACK_WITHOUT_BYTE 0
+#define   SVC_I3C_MCTRL_IBIRESP_ACK_WITH_BYTE BIT(7)
+#define   SVC_I3C_MCTRL_IBIRESP_NACK BIT(6)
+#define   SVC_I3C_MCTRL_IBIRESP_MANUAL GENMASK(7, 6)
+#define   SVC_I3C_MCTRL_DIR(x) FIELD_PREP(BIT(8), (x))
+#define   SVC_I3C_MCTRL_DIR_WRITE 0
+#define   SVC_I3C_MCTRL_DIR_READ 1
+#define   SVC_I3C_MCTRL_ADDR(x) FIELD_PREP(GENMASK(15, 9), (x))
+#define   SVC_I3C_MCTRL_RDTERM(x) FIELD_PREP(GENMASK(23, 16), (x))
+
+#define SVC_I3C_MSTATUS      0x088
+#define   SVC_I3C_MSTATUS_STATE(x) FIELD_GET(GENMASK(2, 0), (x))
+#define   SVC_I3C_MSTATUS_STATE_DAA(x) (SVC_I3C_MSTATUS_STATE(x) == 5)
+#define   SVC_I3C_MSTATUS_STATE_IDLE(x) (SVC_I3C_MSTATUS_STATE(x) == 0)
+#define   SVC_I3C_MSTATUS_BETWEEN(x) FIELD_GET(BIT(4), (x))
+#define   SVC_I3C_MSTATUS_NACKED(x) FIELD_GET(BIT(5), (x))
+#define   SVC_I3C_MSTATUS_IBITYPE(x) FIELD_GET(GENMASK(7, 6), (x))
+#define   SVC_I3C_MSTATUS_IBITYPE_IBI 1
+#define   SVC_I3C_MSTATUS_IBITYPE_MASTER_REQUEST 2
+#define   SVC_I3C_MSTATUS_IBITYPE_HOT_JOIN 3
+#define   SVC_I3C_MINT_SLVSTART BIT(8)
+#define   SVC_I3C_MINT_MCTRLDONE BIT(9)
+#define   SVC_I3C_MINT_COMPLETE BIT(10)
+#define   SVC_I3C_MINT_RXPEND BIT(11)
+#define   SVC_I3C_MINT_TXNOTFULL BIT(12)
+#define   SVC_I3C_MINT_IBIWON BIT(13)
+#define   SVC_I3C_MINT_ERRWARN BIT(15)
+#define   SVC_I3C_MSTATUS_SLVSTART(x) FIELD_GET(SVC_I3C_MINT_SLVSTART, (x))
+#define   SVC_I3C_MSTATUS_MCTRLDONE(x) FIELD_GET(SVC_I3C_MINT_MCTRLDONE, (x))
+#define   SVC_I3C_MSTATUS_COMPLETE(x) FIELD_GET(SVC_I3C_MINT_COMPLETE, (x))
+#define   SVC_I3C_MSTATUS_RXPEND(x) FIELD_GET(SVC_I3C_MINT_RXPEND, (x))
+#define   SVC_I3C_MSTATUS_TXNOTFULL(x) FIELD_GET(SVC_I3C_MINT_TXNOTFULL, (x))
+#define   SVC_I3C_MSTATUS_IBIWON(x) FIELD_GET(SVC_I3C_MINT_IBIWON, (x))
+#define   SVC_I3C_MSTATUS_ERRWARN(x) FIELD_GET(SVC_I3C_MINT_ERRWARN, (x))
+#define   SVC_I3C_MSTATUS_IBIADDR(x) FIELD_GET(GENMASK(30, 24), (x))
+
+#define SVC_I3C_IBIRULES     0x08C
+#define   SVC_I3C_IBIRULES_ADDR(slot, addr) FIELD_PREP(GENMASK(29, 0), \
+						       ((addr) & 0x3F) << ((slot) * 6))
+#define   SVC_I3C_IBIRULES_ADDRS 5
+#define   SVC_I3C_IBIRULES_MSB0 BIT(30)
+#define   SVC_I3C_IBIRULES_NOBYTE BIT(31)
+#define   SVC_I3C_IBIRULES_MANDBYTE 0
+#define SVC_I3C_MINTSET      0x090
+#define SVC_I3C_MINTCLR      0x094
+#define SVC_I3C_MINTMASKED   0x098
+#define SVC_I3C_MERRWARN     0x09C
+#define SVC_I3C_MDMACTRL     0x0A0
+#define SVC_I3C_MDATACTRL    0x0AC
+#define   SVC_I3C_MDATACTRL_FLUSHTB BIT(0)
+#define   SVC_I3C_MDATACTRL_FLUSHRB BIT(1)
+#define   SVC_I3C_MDATACTRL_UNLOCK_TRIG BIT(3)
+#define   SVC_I3C_MDATACTRL_TXTRIG_FIFO_NOT_FULL GENMASK(5, 4)
+#define   SVC_I3C_MDATACTRL_RXTRIG_FIFO_NOT_EMPTY 0
+#define   SVC_I3C_MDATACTRL_RXCOUNT(x) FIELD_GET(GENMASK(28, 24), (x))
+#define   SVC_I3C_MDATACTRL_TXFULL BIT(30)
+#define   SVC_I3C_MDATACTRL_RXEMPTY BIT(31)
+
+#define SVC_I3C_MWDATAB      0x0B0
+#define   SVC_I3C_MWDATAB_END BIT(8)
+
+#define SVC_I3C_MWDATABE     0x0B4
+#define SVC_I3C_MWDATAH      0x0B8
+#define SVC_I3C_MWDATAHE     0x0BC
+#define SVC_I3C_MRDATAB      0x0C0
+#define SVC_I3C_MRDATAH      0x0C8
+#define SVC_I3C_MWMSG_SDR    0x0D0
+#define SVC_I3C_MRMSG_SDR    0x0D4
+#define SVC_I3C_MWMSG_DDR    0x0D8
+#define SVC_I3C_MRMSG_DDR    0x0DC
+
+#define SVC_I3C_MDYNADDR     0x0E4
+#define   SVC_MDYNADDR_VALID BIT(0)
+#define   SVC_MDYNADDR_ADDR(x) FIELD_PREP(GENMASK(7, 1), (x))
+
+#define SVC_I3C_MAX_DEVS 32
+
+/* This parameter depends on the implementation and may be tuned */
+#define SVC_I3C_FIFO_SIZE 16
+
+struct svc_i3c_cmd {
+	u8 addr;
+	bool rnw;
+	u8 *in;
+	const void *out;
+	unsigned int len;
+	unsigned int read_len;
+	bool continued;
+};
+
+struct svc_i3c_xfer {
+	struct list_head node;
+	struct completion comp;
+	int ret;
+	unsigned int type;
+	unsigned int ncmds;
+	struct svc_i3c_cmd cmds[];
+};
+
+/**
+ * struct svc_i3c_master - Silvaco I3C Master structure
+ * @base: I3C master controller
+ * @dev: Corresponding device
+ * @regs: Memory mapping
+ * @free_slots: Bit array of available slots
+ * @addrs: Array containing the dynamic addresses of each attached device
+ * @descs: Array of descriptors, one per attached device
+ * @hj_work: Hot-join work
+ * @ibi_work: IBI work
+ * @irq: Main interrupt
+ * @pclk: System clock
+ * @fclk: Fast clock (bus)
+ * @sclk: Slow clock (other events)
+ * @xferqueue: Transfer queue structure
+ * @xferqueue.list: List member
+ * @xferqueue.cur: Current ongoing transfer
+ * @xferqueue.lock: Queue lock
+ * @ibi: IBI structure
+ * @ibi.num_slots: Number of slots available in @ibi.slots
+ * @ibi.slots: Available IBI slots
+ * @ibi.tbq_slot: To be queued IBI slot
+ * @ibi.lock: IBI lock
+ */
+struct svc_i3c_master {
+	struct i3c_master_controller base;
+	struct device *dev;
+	void __iomem *regs;
+	u32 free_slots;
+	u8 addrs[SVC_I3C_MAX_DEVS];
+	struct i3c_dev_desc *descs[SVC_I3C_MAX_DEVS];
+	struct work_struct hj_work;
+	struct work_struct ibi_work;
+	int irq;
+	struct clk *pclk;
+	struct clk *fclk;
+	struct clk *sclk;
+	struct {
+		struct list_head list;
+		struct svc_i3c_xfer *cur;
+		/* Prevent races between transfers */
+		spinlock_t lock;
+	} xferqueue;
+	struct {
+		unsigned int num_slots;
+		struct i3c_dev_desc **slots;
+		struct i3c_ibi_slot *tbq_slot;
+		/* Prevent races within IBI handlers */
+		spinlock_t lock;
+	} ibi;
+};
+
+/**
+ * struct svc_i3c_i3c_dev_data - Device specific data
+ * @index: Index in the master tables corresponding to this device
+ * @ibi: IBI slot index in the master structure
+ * @ibi_pool: IBI pool associated to this device
+ */
+struct svc_i3c_i2c_dev_data {
+	u8 index;
+	int ibi;
+	struct i3c_generic_ibi_pool *ibi_pool;
+};
+
+static bool svc_i3c_master_error(struct svc_i3c_master *master)
+{
+	u32 mstatus, merrwarn;
+
+	mstatus = readl(master->regs + SVC_I3C_MSTATUS);
+	if (SVC_I3C_MSTATUS_ERRWARN(mstatus)) {
+		merrwarn = readl(master->regs + SVC_I3C_MERRWARN);
+		writel(merrwarn, master->regs + SVC_I3C_MERRWARN);
+		dev_err(master->dev,
+			"Error condition: MSTATUS 0x%08x, MERRWARN 0x%08x\n",
+			mstatus, merrwarn);
+
+		return true;
+	}
+
+	return false;
+}
+
+static void svc_i3c_master_enable_interrupts(struct svc_i3c_master *master, u32 mask)
+{
+	writel(mask, master->regs + SVC_I3C_MINTSET);
+}
+
+static void svc_i3c_master_disable_interrupts(struct svc_i3c_master *master)
+{
+	u32 mask = readl(master->regs + SVC_I3C_MINTSET);
+
+	writel(mask, master->regs + SVC_I3C_MINTCLR);
+}
+
+static inline struct svc_i3c_master *
+to_svc_i3c_master(struct i3c_master_controller *master)
+{
+	return container_of(master, struct svc_i3c_master, base);
+}
+
+static void svc_i3c_master_hj_work(struct work_struct *work)
+{
+	struct svc_i3c_master *master;
+
+	master = container_of(work, struct svc_i3c_master, hj_work);
+	i3c_master_do_daa(&master->base);
+}
+
+static struct i3c_dev_desc *
+svc_i3c_master_dev_from_addr(struct svc_i3c_master *master,
+			     unsigned int ibiaddr)
+{
+	int i;
+
+	for (i = 0; i < SVC_I3C_MAX_DEVS; i++)
+		if (master->addrs[i] == ibiaddr)
+			break;
+
+	if (i == SVC_I3C_MAX_DEVS)
+		return NULL;
+
+	return master->descs[i];
+}
+
+static void svc_i3c_master_emit_stop(struct svc_i3c_master *master)
+{
+	writel(SVC_I3C_MCTRL_REQUEST_STOP, master->regs + SVC_I3C_MCTRL);
+
+	/*
+	 * This delay is necessary after the emission of a stop, otherwise eg.
+	 * repeating IBIs do not get detected. There is a note in the manual
+	 * about it, stating that the stop condition might not be settled
+	 * correctly if a start condition follows too rapidly.
+	 */
+	udelay(1);
+}
+
+static void svc_i3c_master_clear_merrwarn(struct svc_i3c_master *master)
+{
+	writel(readl(master->regs + SVC_I3C_MERRWARN),
+	       master->regs + SVC_I3C_MERRWARN);
+}
+
+static int svc_i3c_master_handle_ibi(struct svc_i3c_master *master,
+				     struct i3c_dev_desc *dev)
+{
+	struct svc_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
+	struct i3c_ibi_slot *slot;
+	unsigned int count;
+	u32 mdatactrl;
+	u8 *buf;
+
+	slot = i3c_generic_ibi_get_free_slot(data->ibi_pool);
+	if (!slot)
+		return -ENOSPC;
+
+	slot->len = 0;
+	buf = slot->data;
+
+	while (SVC_I3C_MSTATUS_RXPEND(readl(master->regs + SVC_I3C_MSTATUS))  &&
+	       slot->len < SVC_I3C_FIFO_SIZE) {
+		mdatactrl = readl(master->regs + SVC_I3C_MDATACTRL);
+		count = SVC_I3C_MDATACTRL_RXCOUNT(mdatactrl);
+		readsl(master->regs + SVC_I3C_MRDATAB, buf, count);
+		slot->len += count;
+		buf += count;
+	}
+
+	master->ibi.tbq_slot = slot;
+
+	return 0;
+}
+
+static void svc_i3c_master_ack_ibi(struct svc_i3c_master *master,
+				   bool mandatory_byte)
+{
+	unsigned int ibi_ack_nack;
+
+	ibi_ack_nack = SVC_I3C_MCTRL_REQUEST_IBI_ACKNACK;
+	if (mandatory_byte)
+		ibi_ack_nack |= SVC_I3C_MCTRL_IBIRESP_ACK_WITH_BYTE;
+	else
+		ibi_ack_nack |= SVC_I3C_MCTRL_IBIRESP_ACK_WITHOUT_BYTE;
+
+	writel(ibi_ack_nack, master->regs + SVC_I3C_MCTRL);
+}
+
+static void svc_i3c_master_nack_ibi(struct svc_i3c_master *master)
+{
+	writel(SVC_I3C_MCTRL_REQUEST_IBI_ACKNACK |
+	       SVC_I3C_MCTRL_IBIRESP_NACK,
+	       master->regs + SVC_I3C_MCTRL);
+}
+
+static void svc_i3c_master_ibi_work(struct work_struct *work)
+{
+	struct svc_i3c_master *master = container_of(work, struct svc_i3c_master, ibi_work);
+	struct svc_i3c_i2c_dev_data *data;
+	unsigned int ibitype, ibiaddr;
+	struct i3c_dev_desc *dev;
+	u32 status, val;
+	int ret;
+
+	/* Acknowledge the incoming interrupt with the AUTOIBI mechanism */
+	writel(SVC_I3C_MCTRL_REQUEST_AUTO_IBI |
+	       SVC_I3C_MCTRL_IBIRESP_AUTO,
+	       master->regs + SVC_I3C_MCTRL);
+
+	/* Wait for IBIWON, should take approximately 100us */
+	ret = readl_relaxed_poll_timeout(master->regs + SVC_I3C_MSTATUS, val,
+					 SVC_I3C_MSTATUS_IBIWON(val), 0, 1000);
+	if (ret) {
+		dev_err(master->dev, "Timeout when polling for IBIWON\n");
+		goto reenable_ibis;
+	}
+
+	/* Clear the interrupt status */
+	writel(SVC_I3C_MINT_IBIWON, master->regs + SVC_I3C_MSTATUS);
+
+	status = readl(master->regs + SVC_I3C_MSTATUS);
+	ibitype = SVC_I3C_MSTATUS_IBITYPE(status);
+	ibiaddr = SVC_I3C_MSTATUS_IBIADDR(status);
+
+	/* Handle the critical responses to IBI's */
+	switch (ibitype) {
+	case SVC_I3C_MSTATUS_IBITYPE_IBI:
+		dev = svc_i3c_master_dev_from_addr(master, ibiaddr);
+		if (!dev)
+			svc_i3c_master_nack_ibi(master);
+		else
+			svc_i3c_master_handle_ibi(master, dev);
+		break;
+	case SVC_I3C_MSTATUS_IBITYPE_HOT_JOIN:
+		svc_i3c_master_ack_ibi(master, false);
+		break;
+	case SVC_I3C_MSTATUS_IBITYPE_MASTER_REQUEST:
+		svc_i3c_master_nack_ibi(master);
+		break;
+	default:
+		break;
+	}
+
+	/*
+	 * If an error happened, we probably got interrupted and the exchange
+	 * timedout. In this case we just drop everything, emit a stop and wait
+	 * for the slave to interrupt again.
+	 */
+	if (svc_i3c_master_error(master)) {
+		if (master->ibi.tbq_slot) {
+			data = i3c_dev_get_master_data(dev);
+			i3c_generic_ibi_recycle_slot(data->ibi_pool,
+						     master->ibi.tbq_slot);
+			master->ibi.tbq_slot = NULL;
+		}
+
+		svc_i3c_master_emit_stop(master);
+
+		goto reenable_ibis;
+	}
+
+	/* Handle the non critical tasks */
+	switch (ibitype) {
+	case SVC_I3C_MSTATUS_IBITYPE_IBI:
+		if (dev) {
+			i3c_master_queue_ibi(dev, master->ibi.tbq_slot);
+			master->ibi.tbq_slot = NULL;
+		}
+		svc_i3c_master_emit_stop(master);
+		break;
+	case SVC_I3C_MSTATUS_IBITYPE_HOT_JOIN:
+		queue_work(master->base.wq, &master->hj_work);
+		break;
+	case SVC_I3C_MSTATUS_IBITYPE_MASTER_REQUEST:
+	default:
+		break;
+	}
+
+reenable_ibis:
+	svc_i3c_master_enable_interrupts(master, SVC_I3C_MINT_SLVSTART);
+}
+
+static irqreturn_t svc_i3c_master_irq_handler(int irq, void *dev_id)
+{
+	struct svc_i3c_master *master = (struct svc_i3c_master *)dev_id;
+	u32 active = readl(master->regs + SVC_I3C_MINTMASKED);
+
+	if (!SVC_I3C_MSTATUS_SLVSTART(active))
+		return IRQ_NONE;
+
+	/* Clear the interrupt status */
+	writel(SVC_I3C_MINT_SLVSTART, master->regs + SVC_I3C_MSTATUS);
+
+	svc_i3c_master_disable_interrupts(master);
+
+	/* Handle the interrupt in a non atomic context */
+	queue_work(master->base.wq, &master->ibi_work);
+
+	return IRQ_HANDLED;
+}
+
+static int svc_i3c_master_bus_init(struct i3c_master_controller *m)
+{
+	struct svc_i3c_master *master = to_svc_i3c_master(m);
+	struct i3c_bus *bus = i3c_master_get_bus(m);
+	struct i3c_device_info info = {};
+	unsigned long fclk_rate, fclk_period_ns;
+	unsigned int high_period_ns, od_low_period_ns;
+	u32 ppbaud, pplow, odhpp, odbaud, i2cbaud, reg;
+	int ret;
+
+	/* Timings derivation */
+	fclk_rate = clk_get_rate(master->fclk);
+	if (!fclk_rate)
+		return -EINVAL;
+
+	fclk_period_ns = DIV_ROUND_UP(1000000000, fclk_rate);
+
+	/*
+	 * Using I3C Push-Pull mode, target is 12.5MHz/80ns period.
+	 * Simplest configuration is using a 50% duty-cycle of 40ns.
+	 */
+	ppbaud = DIV_ROUND_UP(40, fclk_period_ns) - 1;
+	pplow = 0;
+
+	/*
+	 * Using I3C Open-Drain mode, target is 4.17MHz/240ns with a
+	 * duty-cycle tuned so that high levels are filetered out by
+	 * the 50ns filter (target being 40ns).
+	 */
+	odhpp = 1;
+	high_period_ns = (ppbaud + 1) * fclk_period_ns;
+	odbaud = DIV_ROUND_UP(240 - high_period_ns, high_period_ns) - 1;
+	od_low_period_ns = (odbaud + 1) * high_period_ns;
+
+	switch (bus->mode) {
+	case I3C_BUS_MODE_PURE:
+		i2cbaud = 0;
+		break;
+	case I3C_BUS_MODE_MIXED_FAST:
+	case I3C_BUS_MODE_MIXED_LIMITED:
+		/*
+		 * Using I2C Fm+ mode, target is 1MHz/1000ns, the difference
+		 * between the high and low period does not really matter.
+		 */
+		i2cbaud = DIV_ROUND_UP(1000, od_low_period_ns) - 2;
+		break;
+	case I3C_BUS_MODE_MIXED_SLOW:
+		/*
+		 * Using I2C Fm mode, target is 0.4MHz/2500ns, with the same
+		 * constraints as the FM+ mode.
+		 */
+		i2cbaud = DIV_ROUND_UP(2500, od_low_period_ns) - 2;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	reg = SVC_I3C_MCONFIG_MASTER_EN |
+	      SVC_I3C_MCONFIG_DISTO(0) |
+	      SVC_I3C_MCONFIG_HKEEP(0) |
+	      SVC_I3C_MCONFIG_ODSTOP(0) |
+	      SVC_I3C_MCONFIG_PPBAUD(ppbaud) |
+	      SVC_I3C_MCONFIG_PPLOW(pplow) |
+	      SVC_I3C_MCONFIG_ODBAUD(odbaud) |
+	      SVC_I3C_MCONFIG_ODHPP(odhpp) |
+	      SVC_I3C_MCONFIG_SKEW(0) |
+	      SVC_I3C_MCONFIG_I2CBAUD(i2cbaud);
+	writel(reg, master->regs + SVC_I3C_MCONFIG);
+
+	/* Master core's registration */
+	ret = i3c_master_get_free_addr(m, 0);
+	if (ret < 0)
+		return ret;
+
+	info.dyn_addr = ret;
+
+	writel(SVC_MDYNADDR_VALID | SVC_MDYNADDR_ADDR(info.dyn_addr),
+	       master->regs + SVC_I3C_MDYNADDR);
+
+	ret = i3c_master_set_info(&master->base, &info);
+	if (ret)
+		return ret;
+
+	svc_i3c_master_enable_interrupts(master, SVC_I3C_MINT_SLVSTART);
+
+	return 0;
+}
+
+static void svc_i3c_master_bus_cleanup(struct i3c_master_controller *m)
+{
+	struct svc_i3c_master *master = to_svc_i3c_master(m);
+
+	svc_i3c_master_disable_interrupts(master);
+
+	/* Disable master */
+	writel(0, master->regs + SVC_I3C_MCONFIG);
+}
+
+static int svc_i3c_master_reserve_slot(struct svc_i3c_master *master)
+{
+	unsigned int slot;
+
+	if (!(master->free_slots & GENMASK(SVC_I3C_MAX_DEVS - 1, 0)))
+		return -ENOSPC;
+
+	slot = ffs(master->free_slots) - 1;
+
+	master->free_slots &= ~BIT(slot);
+
+	return slot;
+}
+
+static void svc_i3c_master_release_slot(struct svc_i3c_master *master,
+					unsigned int slot)
+{
+	master->free_slots |= BIT(slot);
+}
+
+static int svc_i3c_master_attach_i3c_dev(struct i3c_dev_desc *dev)
+{
+	struct i3c_master_controller *m = i3c_dev_get_master(dev);
+	struct svc_i3c_master *master = to_svc_i3c_master(m);
+	struct svc_i3c_i2c_dev_data *data;
+	int slot;
+
+	slot = svc_i3c_master_reserve_slot(master);
+	if (slot < 0)
+		return slot;
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	if (!data) {
+		svc_i3c_master_release_slot(master, slot);
+		return -ENOMEM;
+	}
+
+	data->ibi = -1;
+	data->index = slot;
+	master->addrs[slot] = dev->info.dyn_addr ? dev->info.dyn_addr :
+						   dev->info.static_addr;
+	master->descs[slot] = dev;
+
+	i3c_dev_set_master_data(dev, data);
+
+	return 0;
+}
+
+static int svc_i3c_master_reattach_i3c_dev(struct i3c_dev_desc *dev,
+					   u8 old_dyn_addr)
+{
+	struct i3c_master_controller *m = i3c_dev_get_master(dev);
+	struct svc_i3c_master *master = to_svc_i3c_master(m);
+	struct svc_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
+
+	master->addrs[data->index] = dev->info.dyn_addr ? dev->info.dyn_addr :
+							  dev->info.static_addr;
+
+	return 0;
+}
+
+static void svc_i3c_master_detach_i3c_dev(struct i3c_dev_desc *dev)
+{
+	struct svc_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
+	struct i3c_master_controller *m = i3c_dev_get_master(dev);
+	struct svc_i3c_master *master = to_svc_i3c_master(m);
+
+	master->addrs[data->index] = 0;
+	svc_i3c_master_release_slot(master, data->index);
+
+	kfree(data);
+}
+
+static int svc_i3c_master_attach_i2c_dev(struct i2c_dev_desc *dev)
+{
+	struct i3c_master_controller *m = i2c_dev_get_master(dev);
+	struct svc_i3c_master *master = to_svc_i3c_master(m);
+	struct svc_i3c_i2c_dev_data *data;
+	int slot;
+
+	slot = svc_i3c_master_reserve_slot(master);
+	if (slot < 0)
+		return slot;
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	if (!data) {
+		svc_i3c_master_release_slot(master, slot);
+		return -ENOMEM;
+	}
+
+	data->index = slot;
+	master->addrs[slot] = dev->addr;
+
+	i2c_dev_set_master_data(dev, data);
+
+	return 0;
+}
+
+static void svc_i3c_master_detach_i2c_dev(struct i2c_dev_desc *dev)
+{
+	struct svc_i3c_i2c_dev_data *data = i2c_dev_get_master_data(dev);
+	struct i3c_master_controller *m = i2c_dev_get_master(dev);
+	struct svc_i3c_master *master = to_svc_i3c_master(m);
+
+	svc_i3c_master_release_slot(master, data->index);
+
+	kfree(data);
+}
+
+static int svc_i3c_master_readb(struct svc_i3c_master *master, u8 *dst,
+				unsigned int len)
+{
+	int ret, i;
+	u32 reg;
+
+	for (i = 0; i < len; i++) {
+		ret = readl_poll_timeout(master->regs + SVC_I3C_MSTATUS, reg,
+					 SVC_I3C_MSTATUS_RXPEND(reg), 0, 1000);
+		if (ret)
+			return ret;
+
+		dst[i] = readl(master->regs + SVC_I3C_MRDATAB);
+	}
+
+	return 0;
+}
+
+static int svc_i3c_master_do_daa_locked(struct svc_i3c_master *master,
+					u8 *addrs, unsigned int *count)
+{
+	u64 prov_id[SVC_I3C_MAX_DEVS] = {}, nacking_prov_id = 0;
+	unsigned int dev_nb = 0, last_addr = 0;
+	u32 reg;
+	int ret, i;
+
+	while (true) {
+		/* Enter/proceed with DAA */
+		writel(SVC_I3C_MCTRL_REQUEST_PROC_DAA |
+		       SVC_I3C_MCTRL_TYPE_I3C |
+		       SVC_I3C_MCTRL_IBIRESP_NACK |
+		       SVC_I3C_MCTRL_DIR(SVC_I3C_MCTRL_DIR_WRITE),
+		       master->regs + SVC_I3C_MCTRL);
+
+		/*
+		 * Either one slave will send its ID, or the assignment process
+		 * is done.
+		 */
+		ret = readl_poll_timeout(master->regs + SVC_I3C_MSTATUS, reg,
+					 SVC_I3C_MSTATUS_RXPEND(reg) |
+					 SVC_I3C_MSTATUS_MCTRLDONE(reg),
+					 1, 1000);
+		if (ret)
+			return ret;
+
+		if (SVC_I3C_MSTATUS_RXPEND(reg)) {
+			u8 data[6];
+
+			/*
+			 * We only care about the 48-bit provisional ID yet to
+			 * be sure a device does not nack an address twice.
+			 * Otherwise, we would just need to flush the RX FIFO.
+			 */
+			ret = svc_i3c_master_readb(master, data, 6);
+			if (ret)
+				return ret;
+
+			for (i = 0; i < 6; i++)
+				prov_id[dev_nb] |= (u64)(data[i]) << (8 * (5 - i));
+
+			/* We do not care about the BCR and DCR yet */
+			ret = svc_i3c_master_readb(master, data, 2);
+			if (ret)
+				return ret;
+		} else if (SVC_I3C_MSTATUS_MCTRLDONE(reg)) {
+			if (SVC_I3C_MSTATUS_STATE_IDLE(reg) &&
+			    SVC_I3C_MSTATUS_COMPLETE(reg)) {
+				/*
+				 * All devices received and acked they dynamic
+				 * address, this is the natural end of the DAA
+				 * procedure.
+				 */
+				break;
+			} else if (SVC_I3C_MSTATUS_NACKED(reg)) {
+				/*
+				 * A slave device nacked the address, this is
+				 * allowed only once, DAA will be stopped and
+				 * then resumed. The same device is supposed to
+				 * answer again immediately and shall ack the
+				 * address this time.
+				 */
+				if (prov_id[dev_nb] == nacking_prov_id)
+					return -EIO;
+
+				dev_nb--;
+				nacking_prov_id = prov_id[dev_nb];
+				svc_i3c_master_emit_stop(master);
+
+				continue;
+			} else {
+				return -EIO;
+			}
+		}
+
+		/* Wait for the slave to be ready to receive its address */
+		ret = readl_poll_timeout(master->regs + SVC_I3C_MSTATUS, reg,
+					 SVC_I3C_MSTATUS_MCTRLDONE(reg) &&
+					 SVC_I3C_MSTATUS_STATE_DAA(reg) &&
+					 SVC_I3C_MSTATUS_BETWEEN(reg),
+					 0, 1000);
+		if (ret)
+			return ret;
+
+		/* Give the slave device a suitable dynamic address */
+		ret = i3c_master_get_free_addr(&master->base, last_addr + 1);
+		if (ret < 0)
+			return ret;
+
+		addrs[dev_nb] = ret;
+		dev_dbg(master->dev, "DAA: device %d assigned to 0x%02x\n",
+			dev_nb, addrs[dev_nb]);
+
+		writel(addrs[dev_nb], master->regs + SVC_I3C_MWDATAB);
+		last_addr = addrs[dev_nb++];
+	}
+
+	*count = dev_nb;
+
+	return 0;
+}
+
+static int svc_i3c_update_ibirules(struct svc_i3c_master *master)
+{
+	struct i3c_dev_desc *dev;
+	u32 reg_mbyte = 0, reg_nobyte = SVC_I3C_IBIRULES_NOBYTE;
+	unsigned int mbyte_addr_ok = 0, mbyte_addr_ko = 0, nobyte_addr_ok = 0,
+		nobyte_addr_ko = 0;
+	bool list_mbyte = false, list_nobyte = false;
+
+	/* Create the IBIRULES register for both cases */
+	i3c_bus_for_each_i3cdev(&master->base.bus, dev) {
+		if (I3C_BCR_DEVICE_ROLE(dev->info.bcr) == I3C_BCR_I3C_MASTER)
+			continue;
+
+		if (dev->info.bcr & I3C_BCR_IBI_PAYLOAD) {
+			reg_mbyte |= SVC_I3C_IBIRULES_ADDR(mbyte_addr_ok,
+							   dev->info.dyn_addr);
+
+			/* IBI rules cannot be applied to devices with MSb=1 */
+			if (dev->info.dyn_addr & BIT(7))
+				mbyte_addr_ko++;
+			else
+				mbyte_addr_ok++;
+		} else {
+			reg_nobyte |= SVC_I3C_IBIRULES_ADDR(nobyte_addr_ok,
+							    dev->info.dyn_addr);
+
+			/* IBI rules cannot be applied to devices with MSb=1 */
+			if (dev->info.dyn_addr & BIT(7))
+				nobyte_addr_ko++;
+			else
+				nobyte_addr_ok++;
+		}
+	}
+
+	/* Device list cannot be handled by hardware */
+	if (!mbyte_addr_ko && mbyte_addr_ok <= SVC_I3C_IBIRULES_ADDRS)
+		list_mbyte = true;
+
+	if (!nobyte_addr_ko && nobyte_addr_ok <= SVC_I3C_IBIRULES_ADDRS)
+		list_nobyte = true;
+
+	/* No list can be properly handled, return an error */
+	if (!list_mbyte && !list_nobyte)
+		return -ERANGE;
+
+	/* Pick the first list that can be handled by hardware, randomly */
+	if (list_mbyte)
+		writel(reg_mbyte, master->regs + SVC_I3C_IBIRULES);
+	else
+		writel(reg_nobyte, master->regs + SVC_I3C_IBIRULES);
+
+	return 0;
+}
+
+static int svc_i3c_master_do_daa(struct i3c_master_controller *m)
+{
+	struct svc_i3c_master *master = to_svc_i3c_master(m);
+	u8 addrs[SVC_I3C_MAX_DEVS];
+	unsigned long flags;
+	unsigned int dev_nb;
+	int ret, i;
+
+	spin_lock_irqsave(&master->xferqueue.lock, flags);
+	ret = svc_i3c_master_do_daa_locked(master, addrs, &dev_nb);
+	spin_unlock_irqrestore(&master->xferqueue.lock, flags);
+	if (ret)
+		goto emit_stop;
+
+	/* Register all devices who participated to the core */
+	for (i = 0; i < dev_nb; i++) {
+		ret = i3c_master_add_i3c_dev_locked(m, addrs[i]);
+		if (ret)
+			return ret;
+	}
+
+	/* Configure IBI auto-rules */
+	ret = svc_i3c_update_ibirules(master);
+	if (ret) {
+		dev_err(master->dev, "Cannot handle such a list of devices");
+		return ret;
+	}
+
+	return 0;
+
+emit_stop:
+	svc_i3c_master_emit_stop(master);
+	svc_i3c_master_clear_merrwarn(master);
+
+	return ret;
+}
+
+static int svc_i3c_master_read(struct svc_i3c_master *master,
+			       u8 *in, unsigned int len)
+{
+	int offset = 0, i, ret;
+	u32 mdctrl;
+
+	while (offset < len) {
+		unsigned int count;
+
+		ret = readl_poll_timeout(master->regs + SVC_I3C_MDATACTRL,
+					 mdctrl,
+					 !(mdctrl & SVC_I3C_MDATACTRL_RXEMPTY),
+					 0, 1000);
+		if (ret)
+			return ret;
+
+		count = SVC_I3C_MDATACTRL_RXCOUNT(mdctrl);
+		for (i = 0; i < count; i++)
+			in[offset + i] = readl(master->regs + SVC_I3C_MRDATAB);
+
+		offset += count;
+	}
+
+	return 0;
+}
+
+static int svc_i3c_master_write(struct svc_i3c_master *master,
+				const u8 *out, unsigned int len)
+{
+	int offset = 0, ret;
+	u32 mdctrl;
+
+	while (offset < len) {
+		ret = readl_poll_timeout(master->regs + SVC_I3C_MDATACTRL,
+					 mdctrl,
+					 !(mdctrl & SVC_I3C_MDATACTRL_TXFULL),
+					 0, 1000);
+		if (ret)
+			return ret;
+
+		/*
+		 * The last byte to be sent over the bus must either have the
+		 * "end" bit set or be written in MWDATABE.
+		 */
+		if (likely(offset < (len - 1)))
+			writel(out[offset++], master->regs + SVC_I3C_MWDATAB);
+		else
+			writel(out[offset++], master->regs + SVC_I3C_MWDATABE);
+	}
+
+	return 0;
+}
+
+static int svc_i3c_master_xfer(struct svc_i3c_master *master,
+			       bool rnw, unsigned int xfer_type, u8 addr,
+			       u8 *in, const u8 *out, unsigned int xfer_len,
+			       unsigned int read_len, bool continued)
+{
+	u32 reg;
+	int ret;
+
+	writel(SVC_I3C_MCTRL_REQUEST_START_ADDR |
+	       xfer_type |
+	       SVC_I3C_MCTRL_IBIRESP_NACK |
+	       SVC_I3C_MCTRL_DIR(rnw) |
+	       SVC_I3C_MCTRL_ADDR(addr) |
+	       SVC_I3C_MCTRL_RDTERM(read_len),
+	       master->regs + SVC_I3C_MCTRL);
+
+	ret = readl_poll_timeout(master->regs + SVC_I3C_MSTATUS, reg,
+				 SVC_I3C_MSTATUS_MCTRLDONE(reg), 0, 1000);
+	if (ret)
+		goto emit_stop;
+
+	if (rnw)
+		ret = svc_i3c_master_read(master, in, xfer_len);
+	else
+		ret = svc_i3c_master_write(master, out, xfer_len);
+	if (ret)
+		goto emit_stop;
+
+	ret = readl_poll_timeout(master->regs + SVC_I3C_MSTATUS, reg,
+				 SVC_I3C_MSTATUS_COMPLETE(reg), 0, 1000);
+	if (ret)
+		goto emit_stop;
+
+	if (!continued)
+		svc_i3c_master_emit_stop(master);
+
+	return 0;
+
+emit_stop:
+	svc_i3c_master_emit_stop(master);
+	svc_i3c_master_clear_merrwarn(master);
+
+	return ret;
+}
+
+static struct svc_i3c_xfer *
+svc_i3c_master_alloc_xfer(struct svc_i3c_master *master, unsigned int ncmds)
+{
+	struct svc_i3c_xfer *xfer;
+
+	xfer = kzalloc(struct_size(xfer, cmds, ncmds), GFP_KERNEL);
+	if (!xfer)
+		return NULL;
+
+	INIT_LIST_HEAD(&xfer->node);
+	xfer->ncmds = ncmds;
+	xfer->ret = -ETIMEDOUT;
+
+	return xfer;
+}
+
+static void svc_i3c_master_free_xfer(struct svc_i3c_xfer *xfer)
+{
+	kfree(xfer);
+}
+
+static void svc_i3c_master_dequeue_xfer_locked(struct svc_i3c_master *master,
+					       struct svc_i3c_xfer *xfer)
+{
+	if (master->xferqueue.cur == xfer)
+		master->xferqueue.cur = NULL;
+	else
+		list_del_init(&xfer->node);
+}
+
+static void svc_i3c_master_dequeue_xfer(struct svc_i3c_master *master,
+					struct svc_i3c_xfer *xfer)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&master->xferqueue.lock, flags);
+	svc_i3c_master_dequeue_xfer_locked(master, xfer);
+	spin_unlock_irqrestore(&master->xferqueue.lock, flags);
+}
+
+static void svc_i3c_master_start_xfer_locked(struct svc_i3c_master *master)
+{
+	struct svc_i3c_xfer *xfer = master->xferqueue.cur;
+	int ret, i;
+
+	if (!xfer)
+		return;
+
+	for (i = 0; i < xfer->ncmds; i++) {
+		struct svc_i3c_cmd *cmd = &xfer->cmds[i];
+
+		ret = svc_i3c_master_xfer(master, cmd->rnw, xfer->type,
+					  cmd->addr, cmd->in, cmd->out,
+					  cmd->len, cmd->read_len,
+					  cmd->continued);
+		if (ret)
+			break;
+	}
+
+	xfer->ret = ret;
+	complete(&xfer->comp);
+
+	if (ret < 0)
+		svc_i3c_master_dequeue_xfer_locked(master, xfer);
+
+	xfer = list_first_entry_or_null(&master->xferqueue.list,
+					struct svc_i3c_xfer,
+					node);
+	if (xfer)
+		list_del_init(&xfer->node);
+
+	master->xferqueue.cur = xfer;
+	svc_i3c_master_start_xfer_locked(master);
+}
+
+static void svc_i3c_master_enqueue_xfer(struct svc_i3c_master *master,
+					struct svc_i3c_xfer *xfer)
+{
+	unsigned long flags;
+
+	init_completion(&xfer->comp);
+	spin_lock_irqsave(&master->xferqueue.lock, flags);
+	if (master->xferqueue.cur) {
+		list_add_tail(&xfer->node, &master->xferqueue.list);
+	} else {
+		master->xferqueue.cur = xfer;
+		svc_i3c_master_start_xfer_locked(master);
+	}
+	spin_unlock_irqrestore(&master->xferqueue.lock, flags);
+}
+
+static bool
+svc_i3c_master_supports_ccc_cmd(struct i3c_master_controller *master,
+				const struct i3c_ccc_cmd *cmd)
+{
+	/* No software support for CCC commands targeting more than one slave */
+	return (cmd->ndests == 1);
+}
+
+static int svc_i3c_master_send_bdcast_ccc_cmd(struct svc_i3c_master *master,
+					      struct i3c_ccc_cmd *ccc)
+{
+	unsigned int xfer_len = ccc->dests[0].payload.len + 1;
+	struct svc_i3c_xfer *xfer;
+	struct svc_i3c_cmd *cmd;
+	u8 *buf;
+	int ret;
+
+	xfer = svc_i3c_master_alloc_xfer(master, 1);
+	if (!xfer)
+		return -ENOMEM;
+
+	buf = kmalloc(xfer_len, GFP_KERNEL);
+	if (!buf) {
+		svc_i3c_master_free_xfer(xfer);
+		return -ENOMEM;
+	}
+
+	buf[0] = ccc->id;
+	memcpy(&buf[1], ccc->dests[0].payload.data, ccc->dests[0].payload.len);
+
+	xfer->type = SVC_I3C_MCTRL_TYPE_I3C;
+
+	cmd = &xfer->cmds[0];
+	cmd->addr = ccc->dests[0].addr;
+	cmd->rnw = ccc->rnw;
+	cmd->in = NULL;
+	cmd->out = buf;
+	cmd->len = xfer_len;
+	cmd->read_len = 0;
+	cmd->continued = false;
+
+	svc_i3c_master_enqueue_xfer(master, xfer);
+	if (!wait_for_completion_timeout(&xfer->comp, msecs_to_jiffies(1000)))
+		svc_i3c_master_dequeue_xfer(master, xfer);
+
+	ret = xfer->ret;
+	kfree(buf);
+	svc_i3c_master_free_xfer(xfer);
+
+	return ret;
+}
+
+static int svc_i3c_master_send_direct_ccc_cmd(struct svc_i3c_master *master,
+					      struct i3c_ccc_cmd *ccc)
+{
+	unsigned int xfer_len = ccc->dests[0].payload.len;
+	unsigned int read_len = ccc->rnw ? xfer_len : 0;
+	struct svc_i3c_xfer *xfer;
+	struct svc_i3c_cmd *cmd;
+	int ret;
+
+	xfer = svc_i3c_master_alloc_xfer(master, 2);
+	if (!xfer)
+		return -ENOMEM;
+
+	xfer->type = SVC_I3C_MCTRL_TYPE_I3C;
+
+	/* Broadcasted message */
+	cmd = &xfer->cmds[0];
+	cmd->addr = I3C_BROADCAST_ADDR;
+	cmd->rnw = 0;
+	cmd->in = NULL;
+	cmd->out = &ccc->id;
+	cmd->len = 1;
+	cmd->read_len = xfer_len;
+	cmd->read_len = 0;
+	cmd->continued = true;
+
+	/* Directed message */
+	cmd = &xfer->cmds[1];
+	cmd->addr = ccc->dests[0].addr;
+	cmd->rnw = ccc->rnw;
+	cmd->in = ccc->rnw ? ccc->dests[0].payload.data : NULL;
+	cmd->out = ccc->rnw ? NULL : ccc->dests[0].payload.data,
+	cmd->len = xfer_len;
+	cmd->read_len = read_len;
+	cmd->continued = false;
+
+	svc_i3c_master_enqueue_xfer(master, xfer);
+	if (!wait_for_completion_timeout(&xfer->comp, msecs_to_jiffies(1000)))
+		svc_i3c_master_dequeue_xfer(master, xfer);
+
+	ret = xfer->ret;
+	svc_i3c_master_free_xfer(xfer);
+
+	return ret;
+}
+
+static int svc_i3c_master_send_ccc_cmd(struct i3c_master_controller *m,
+				       struct i3c_ccc_cmd *cmd)
+{
+	struct svc_i3c_master *master = to_svc_i3c_master(m);
+	bool broadcast = cmd->id < 0x80;
+
+	if (broadcast)
+		return svc_i3c_master_send_bdcast_ccc_cmd(master, cmd);
+	else
+		return svc_i3c_master_send_direct_ccc_cmd(master, cmd);
+}
+
+static int svc_i3c_master_priv_xfers(struct i3c_dev_desc *dev,
+				     struct i3c_priv_xfer *xfers,
+				     int nxfers)
+{
+	struct i3c_master_controller *m = i3c_dev_get_master(dev);
+	struct svc_i3c_master *master = to_svc_i3c_master(m);
+	struct svc_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
+	struct svc_i3c_xfer *xfer;
+	int ret, i;
+
+	xfer = svc_i3c_master_alloc_xfer(master, nxfers);
+	if (!xfer)
+		return -ENOMEM;
+
+	xfer->type = SVC_I3C_MCTRL_TYPE_I3C;
+
+	for (i = 0; i < nxfers; i++) {
+		struct svc_i3c_cmd *cmd = &xfer->cmds[i];
+
+		cmd->addr = master->addrs[data->index];
+		cmd->rnw = xfers[i].rnw;
+		cmd->in = xfers[i].rnw ? xfers[i].data.in : NULL;
+		cmd->out = xfers[i].rnw ? NULL : xfers[i].data.out;
+		cmd->len = xfers[i].len;
+		cmd->read_len = xfers[i].rnw ? xfers[i].len : 0;
+		cmd->continued = (i + 1) < nxfers;
+	}
+
+	svc_i3c_master_enqueue_xfer(master, xfer);
+	if (!wait_for_completion_timeout(&xfer->comp, msecs_to_jiffies(1000)))
+		svc_i3c_master_dequeue_xfer(master, xfer);
+
+	ret = xfer->ret;
+	svc_i3c_master_free_xfer(xfer);
+
+	return ret;
+}
+
+static int svc_i3c_master_i2c_xfers(struct i2c_dev_desc *dev,
+				    const struct i2c_msg *xfers,
+				    int nxfers)
+{
+	struct i3c_master_controller *m = i2c_dev_get_master(dev);
+	struct svc_i3c_master *master = to_svc_i3c_master(m);
+	struct svc_i3c_i2c_dev_data *data = i2c_dev_get_master_data(dev);
+	struct svc_i3c_xfer *xfer;
+	int ret, i;
+
+	xfer = svc_i3c_master_alloc_xfer(master, nxfers);
+	if (!xfer)
+		return -ENOMEM;
+
+	xfer->type = SVC_I3C_MCTRL_TYPE_I2C;
+
+	for (i = 0; i < nxfers; i++) {
+		struct svc_i3c_cmd *cmd = &xfer->cmds[i];
+
+		cmd->addr = master->addrs[data->index];
+		cmd->rnw = xfers[i].flags & I2C_M_RD;
+		cmd->in = cmd->rnw ? xfers[i].buf : NULL;
+		cmd->out = cmd->rnw ? NULL : xfers[i].buf;
+		cmd->len = xfers[i].len;
+		cmd->read_len = cmd->rnw ? xfers[i].len : 0;
+		cmd->continued = (i + 1 < nxfers);
+	}
+
+	svc_i3c_master_enqueue_xfer(master, xfer);
+	if (!wait_for_completion_timeout(&xfer->comp, msecs_to_jiffies(1000)))
+		svc_i3c_master_dequeue_xfer(master, xfer);
+
+	ret = xfer->ret;
+	svc_i3c_master_free_xfer(xfer);
+
+	return ret;
+}
+
+static int svc_i3c_master_request_ibi(struct i3c_dev_desc *dev,
+				      const struct i3c_ibi_setup *req)
+{
+	struct i3c_master_controller *m = i3c_dev_get_master(dev);
+	struct svc_i3c_master *master = to_svc_i3c_master(m);
+	struct svc_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
+	unsigned long flags;
+	unsigned int i;
+
+	if (dev->ibi->max_payload_len > SVC_I3C_FIFO_SIZE) {
+		dev_err(master->dev, "IBI max payload %d should be < %d\n",
+			dev->ibi->max_payload_len, SVC_I3C_FIFO_SIZE);
+		return -ERANGE;
+	}
+
+	data->ibi_pool = i3c_generic_ibi_alloc_pool(dev, req);
+	if (IS_ERR(data->ibi_pool))
+		return PTR_ERR(data->ibi_pool);
+
+	spin_lock_irqsave(&master->ibi.lock, flags);
+	for (i = 0; i < master->ibi.num_slots; i++) {
+		if (!master->ibi.slots[i]) {
+			data->ibi = i;
+			master->ibi.slots[i] = dev;
+			break;
+		}
+	}
+	spin_unlock_irqrestore(&master->ibi.lock, flags);
+
+	if (i < master->ibi.num_slots)
+		return 0;
+
+	i3c_generic_ibi_free_pool(data->ibi_pool);
+	data->ibi_pool = NULL;
+
+	return -ENOSPC;
+}
+
+static void svc_i3c_master_free_ibi(struct i3c_dev_desc *dev)
+{
+	struct i3c_master_controller *m = i3c_dev_get_master(dev);
+	struct svc_i3c_master *master = to_svc_i3c_master(m);
+	struct svc_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
+	unsigned long flags;
+
+	spin_lock_irqsave(&master->ibi.lock, flags);
+	master->ibi.slots[data->ibi] = NULL;
+	data->ibi = -1;
+	spin_unlock_irqrestore(&master->ibi.lock, flags);
+
+	i3c_generic_ibi_free_pool(data->ibi_pool);
+}
+
+static int svc_i3c_master_enable_ibi(struct i3c_dev_desc *dev)
+{
+	struct i3c_master_controller *m = i3c_dev_get_master(dev);
+
+	return i3c_master_enec_locked(m, dev->info.dyn_addr, I3C_CCC_EVENT_SIR);
+}
+
+static int svc_i3c_master_disable_ibi(struct i3c_dev_desc *dev)
+{
+	struct i3c_master_controller *m = i3c_dev_get_master(dev);
+
+	return i3c_master_disec_locked(m, dev->info.dyn_addr, I3C_CCC_EVENT_SIR);
+}
+
+static void svc_i3c_master_recycle_ibi_slot(struct i3c_dev_desc *dev,
+					    struct i3c_ibi_slot *slot)
+{
+	struct svc_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
+
+	i3c_generic_ibi_recycle_slot(data->ibi_pool, slot);
+}
+
+static const struct i3c_master_controller_ops svc_i3c_master_ops = {
+	.bus_init = svc_i3c_master_bus_init,
+	.bus_cleanup = svc_i3c_master_bus_cleanup,
+	.attach_i3c_dev = svc_i3c_master_attach_i3c_dev,
+	.detach_i3c_dev = svc_i3c_master_detach_i3c_dev,
+	.reattach_i3c_dev = svc_i3c_master_reattach_i3c_dev,
+	.attach_i2c_dev = svc_i3c_master_attach_i2c_dev,
+	.detach_i2c_dev = svc_i3c_master_detach_i2c_dev,
+	.do_daa = svc_i3c_master_do_daa,
+	.supports_ccc_cmd = svc_i3c_master_supports_ccc_cmd,
+	.send_ccc_cmd = svc_i3c_master_send_ccc_cmd,
+	.priv_xfers = svc_i3c_master_priv_xfers,
+	.i2c_xfers = svc_i3c_master_i2c_xfers,
+	.request_ibi = svc_i3c_master_request_ibi,
+	.free_ibi = svc_i3c_master_free_ibi,
+	.recycle_ibi_slot = svc_i3c_master_recycle_ibi_slot,
+	.enable_ibi = svc_i3c_master_enable_ibi,
+	.disable_ibi = svc_i3c_master_disable_ibi,
+};
+
+static void svc_i3c_master_reset(struct svc_i3c_master *master)
+{
+	u32 reg;
+
+	/* Clear pending warnings */
+	writel(readl(master->regs + SVC_I3C_MERRWARN),
+	       master->regs + SVC_I3C_MERRWARN);
+
+	/* Set RX and TX tigger levels, flush FIFOs */
+	reg = SVC_I3C_MDATACTRL_FLUSHTB |
+	      SVC_I3C_MDATACTRL_FLUSHRB |
+	      SVC_I3C_MDATACTRL_UNLOCK_TRIG |
+	      SVC_I3C_MDATACTRL_TXTRIG_FIFO_NOT_FULL |
+	      SVC_I3C_MDATACTRL_RXTRIG_FIFO_NOT_EMPTY;
+	writel(reg, master->regs + SVC_I3C_MDATACTRL);
+
+	svc_i3c_master_disable_interrupts(master);
+}
+
+static int svc_i3c_master_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct svc_i3c_master *master;
+	int ret;
+
+	master = devm_kzalloc(dev, sizeof(*master), GFP_KERNEL);
+	if (!master)
+		return -ENOMEM;
+
+	master->regs = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(master->regs))
+		return PTR_ERR(master->regs);
+
+	master->pclk = devm_clk_get(dev, "pclk");
+	if (IS_ERR(master->pclk))
+		return PTR_ERR(master->pclk);
+
+	master->fclk = devm_clk_get(dev, "fast_clk");
+	if (IS_ERR(master->fclk))
+		return PTR_ERR(master->fclk);
+
+	master->sclk = devm_clk_get(dev, "slow_clk");
+	if (IS_ERR(master->sclk))
+		return PTR_ERR(master->sclk);
+
+	master->irq = platform_get_irq(pdev, 0);
+	if (master->irq <= 0)
+		return -ENOENT;
+
+	master->dev = dev;
+
+	svc_i3c_master_reset(master);
+
+	ret = clk_prepare_enable(master->pclk);
+	if (ret)
+		return ret;
+
+	ret = clk_prepare_enable(master->fclk);
+	if (ret)
+		goto err_disable_pclk;
+
+	ret = clk_prepare_enable(master->sclk);
+	if (ret)
+		goto err_disable_fclk;
+
+	INIT_WORK(&master->hj_work, svc_i3c_master_hj_work);
+	INIT_WORK(&master->ibi_work, svc_i3c_master_ibi_work);
+	ret = devm_request_irq(dev, master->irq, svc_i3c_master_irq_handler,
+			       IRQF_NO_SUSPEND, "svc-i3c-irq", master);
+	if (ret)
+		goto err_disable_sclk;
+
+	master->free_slots = GENMASK(SVC_I3C_MAX_DEVS - 1, 0);
+
+	spin_lock_init(&master->xferqueue.lock);
+	INIT_LIST_HEAD(&master->xferqueue.list);
+
+	spin_lock_init(&master->ibi.lock);
+	master->ibi.num_slots = SVC_I3C_MAX_DEVS;
+	master->ibi.slots = devm_kcalloc(&pdev->dev, master->ibi.num_slots,
+					 sizeof(*master->ibi.slots),
+					 GFP_KERNEL);
+	if (!master->ibi.slots) {
+		ret = -ENOMEM;
+		goto err_disable_sclk;
+	}
+
+	platform_set_drvdata(pdev, master);
+
+	/* Register the master */
+	ret = i3c_master_register(&master->base, &pdev->dev,
+				  &svc_i3c_master_ops, false);
+	if (ret)
+		goto err_disable_sclk;
+
+	return 0;
+
+err_disable_sclk:
+	clk_disable_unprepare(master->sclk);
+
+err_disable_fclk:
+	clk_disable_unprepare(master->fclk);
+
+err_disable_pclk:
+	clk_disable_unprepare(master->pclk);
+
+	return ret;
+}
+
+static int svc_i3c_master_remove(struct platform_device *pdev)
+{
+	struct svc_i3c_master *master = platform_get_drvdata(pdev);
+	int ret;
+
+	ret = i3c_master_unregister(&master->base);
+	if (ret)
+		return ret;
+
+	free_irq(master->irq, master);
+	clk_disable_unprepare(master->pclk);
+	clk_disable_unprepare(master->fclk);
+	clk_disable_unprepare(master->sclk);
+
+	return 0;
+}
+
+static const struct of_device_id svc_i3c_master_of_match_tbl[] = {
+	{ .compatible = "silvaco,i3c-master" },
+	{ /* sentinel */ },
+};
+
+static struct platform_driver svc_i3c_master = {
+	.probe = svc_i3c_master_probe,
+	.remove = svc_i3c_master_remove,
+	.driver = {
+		.name = "silvaco-i3c-master",
+		.of_match_table = svc_i3c_master_of_match_tbl,
+	},
+};
+module_platform_driver(svc_i3c_master);
+
+MODULE_AUTHOR("Conor Culhane <conor.culhane@silvaco.com>");
+MODULE_AUTHOR("Miquel Raynal <miquel.raynal@bootlin.com>");
+MODULE_DESCRIPTION("Silvaco dual-role I3C master driver");
+MODULE_LICENSE("GPL v2");
-- 
2.20.1


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^ permalink raw reply related	[flat|nested] 10+ messages in thread

* [PATCH v5 6/6] MAINTAINERS: Add Silvaco I3C master
  2021-01-21 10:18 [PATCH v5 0/6] Silvaco I3C master driver Miquel Raynal
                   ` (4 preceding siblings ...)
  2021-01-21 10:18 ` [PATCH v5 5/6] i3c: master: svc: Add Silvaco I3C master driver Miquel Raynal
@ 2021-01-21 10:18 ` Miquel Raynal
  2021-02-05 23:44 ` [PATCH v5 0/6] Silvaco I3C master driver Alexandre Belloni
  6 siblings, 0 replies; 10+ messages in thread
From: Miquel Raynal @ 2021-01-21 10:18 UTC (permalink / raw)
  To: Alexandre Belloni, linux-i3c, Rob Herring, devicetree
  Cc: Miquel Raynal, Rajeev Huralikoppi, Conor Culhane,
	Thomas Petazzoni, Nicolas Pitre

Add Conor and myself as maintainers.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
---
 MAINTAINERS | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index 546aa66428c9..caa4e1ea32a7 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -16237,6 +16237,14 @@ S:	Maintained
 F:	Documentation/fb/sm712fb.rst
 F:	drivers/video/fbdev/sm712*
 
+SILVACO I3C DUAL-ROLE MASTER
+M:	Miquel Raynal <miquel.raynal@bootlin.com>
+M:	Conor Culhane <conor.culhane@silvaco.com>
+L:	linux-i3c@lists.infradead.org
+S:	Maintained
+F:	Documentation/devicetree/bindings/i3c/silvaco,i3c-master.yaml
+F:	drivers/i3c/master/svc-i3c-master.c
+
 SIMPLE FIRMWARE INTERFACE (SFI)
 S:	Obsolete
 W:	http://simplefirmware.org/
-- 
2.20.1


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^ permalink raw reply related	[flat|nested] 10+ messages in thread

* Re: [PATCH v5 1/6] dt-bindings: i3c: Convert the bus description to yaml
  2021-01-21 10:18 ` [PATCH v5 1/6] dt-bindings: i3c: Convert the bus description to yaml Miquel Raynal
@ 2021-02-05 21:31   ` Rob Herring
  0 siblings, 0 replies; 10+ messages in thread
From: Rob Herring @ 2021-02-05 21:31 UTC (permalink / raw)
  To: Miquel Raynal
  Cc: devicetree, Alexandre Belloni, Rajeev Huralikoppi, Nicolas Pitre,
	Rob Herring, Thomas Petazzoni, linux-i3c, Conor Culhane

On Thu, 21 Jan 2021 11:18:03 +0100, Miquel Raynal wrote:
> Attempting a conversion of the i3c.txt file to yaml schema with
> minimal content changes.
> 
> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
> ---
>  Documentation/devicetree/bindings/i3c/i3c.txt | 140 --------------
>  .../devicetree/bindings/i3c/i3c.yaml          | 179 ++++++++++++++++++
>  2 files changed, 179 insertions(+), 140 deletions(-)
>  delete mode 100644 Documentation/devicetree/bindings/i3c/i3c.txt
>  create mode 100644 Documentation/devicetree/bindings/i3c/i3c.yaml
> 

Reviewed-by: Rob Herring <robh@kernel.org>

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^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: [PATCH v5 2/6] dt-bindings: i3c: mipi-hci: Include the bus binding
  2021-01-21 10:18 ` [PATCH v5 2/6] dt-bindings: i3c: mipi-hci: Include the bus binding Miquel Raynal
@ 2021-02-05 21:31   ` Rob Herring
  0 siblings, 0 replies; 10+ messages in thread
From: Rob Herring @ 2021-02-05 21:31 UTC (permalink / raw)
  To: Miquel Raynal
  Cc: devicetree, Alexandre Belloni, Rajeev Huralikoppi, Nicolas Pitre,
	Rob Herring, Thomas Petazzoni, linux-i3c, Conor Culhane

On Thu, 21 Jan 2021 11:18:04 +0100, Miquel Raynal wrote:
> Update a little bit the content to match the bus binding, including:
> - the node title should have been named after the description done
>   in the historical i3c.txt file, ie: i3c-master@<address>
> - child nodes should be accepted even though the drivers do not currently
>   support it
> - #address-cells and #size-cells are also mandatory and have specific
>   values
> 
> Cc: Nicolas Pitre <nico@fluxnic.net>
> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
> ---
>  Documentation/devicetree/bindings/i3c/mipi-i3c-hci.yaml | 9 +++++++--
>  1 file changed, 7 insertions(+), 2 deletions(-)
> 

Reviewed-by: Rob Herring <robh@kernel.org>

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^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: [PATCH v5 0/6] Silvaco I3C master driver
  2021-01-21 10:18 [PATCH v5 0/6] Silvaco I3C master driver Miquel Raynal
                   ` (5 preceding siblings ...)
  2021-01-21 10:18 ` [PATCH v5 6/6] MAINTAINERS: Add Silvaco I3C master Miquel Raynal
@ 2021-02-05 23:44 ` Alexandre Belloni
  6 siblings, 0 replies; 10+ messages in thread
From: Alexandre Belloni @ 2021-02-05 23:44 UTC (permalink / raw)
  To: Miquel Raynal, Rob Herring, devicetree, linux-i3c
  Cc: Alexandre Belloni, Rajeev Huralikoppi, Conor Culhane,
	Thomas Petazzoni, Nicolas Pitre

On Thu, 21 Jan 2021 11:18:02 +0100, Miquel Raynal wrote:
> Here is the addition of a driver for the Silvaco I3C master IP.
> 
> Changes in v5:
> * Added Rob's R-by when relevant.
> * Fixed the robots warnings by pushing a little bit forward the changes in the
>   mipi-hci binding file.
> * Fixed the I3C master node name regex.
> * Removed the redundant $ref: entries when the hz suffix is used.
> * Simplified a little bit the regexes defining the child nodes.
> * Updated the reg propertie description to better describe each entry.
> 
> [...]

Applied, thanks!

[1/6] dt-bindings: i3c: Convert the bus description to yaml
      commit: 5e4cdca887fdb445f962b3dbc2a2514d7c025d9b
[2/6] dt-bindings: i3c: mipi-hci: Include the bus binding
      commit: de67276e66fcfcd404516eebfd6436239dd9882a
[3/6] dt-bindings: Add vendor prefix for Silvaco
      commit: 57f7c9ff1b3fdc2cccb377207e538bf5f3ab03cf
[4/6] dt-bindings: i3c: Describe Silvaco master binding
      commit: b8b0446f1f1afd58e5a9ba14ab2caa08797f3bb5
[5/6] i3c: master: svc: Add Silvaco I3C master driver
      commit: dd3c52846d5954acd43f0e771689302f27dadc28
[6/6] MAINTAINERS: Add Silvaco I3C master
      commit: f06a1af8e739cb573b79cd175fd88534e912bea0

Best regards,
-- 
Alexandre Belloni <alexandre.belloni@bootlin.com>

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^ permalink raw reply	[flat|nested] 10+ messages in thread

end of thread, other threads:[~2021-02-05 23:44 UTC | newest]

Thread overview: 10+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-01-21 10:18 [PATCH v5 0/6] Silvaco I3C master driver Miquel Raynal
2021-01-21 10:18 ` [PATCH v5 1/6] dt-bindings: i3c: Convert the bus description to yaml Miquel Raynal
2021-02-05 21:31   ` Rob Herring
2021-01-21 10:18 ` [PATCH v5 2/6] dt-bindings: i3c: mipi-hci: Include the bus binding Miquel Raynal
2021-02-05 21:31   ` Rob Herring
2021-01-21 10:18 ` [PATCH v5 3/6] dt-bindings: Add vendor prefix for Silvaco Miquel Raynal
2021-01-21 10:18 ` [PATCH v5 4/6] dt-bindings: i3c: Describe Silvaco master binding Miquel Raynal
2021-01-21 10:18 ` [PATCH v5 5/6] i3c: master: svc: Add Silvaco I3C master driver Miquel Raynal
2021-01-21 10:18 ` [PATCH v5 6/6] MAINTAINERS: Add Silvaco I3C master Miquel Raynal
2021-02-05 23:44 ` [PATCH v5 0/6] Silvaco I3C master driver Alexandre Belloni

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