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-rw-r--r--Documentation/devicetree/bindings/i2c/ce4100-i2c.txt93
-rw-r--r--Documentation/devicetree/bindings/x86/ce4100.txt38
-rw-r--r--Documentation/devicetree/bindings/x86/interrupt.txt29
-rw-r--r--Documentation/devicetree/bindings/x86/timer.txt6
4 files changed, 166 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/i2c/ce4100-i2c.txt b/Documentation/devicetree/bindings/i2c/ce4100-i2c.txt
new file mode 100644
index 000000000000..569b16248514
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/ce4100-i2c.txt
@@ -0,0 +1,93 @@
+CE4100 I2C
+----------
+
+CE4100 has one PCI device which is described as the I2C-Controller. This
+PCI device has three PCI-bars, each bar contains a complete I2C
+controller. So we have a total of three independent I2C-Controllers
+which share only an interrupt line.
+The driver is probed via the PCI-ID and is gathering the information of
+attached devices from the devices tree.
+Grant Likely recommended to use the ranges property to map the PCI-Bar
+number to its physical address and to use this to find the child nodes
+of the specific I2C controller. This were his exact words:
+
+ Here's where the magic happens. Each entry in
+ ranges describes how the parent pci address space
+ (middle group of 3) is translated to the local
+ address space (first group of 2) and the size of
+ each range (last cell). In this particular case,
+ the first cell of the local address is chosen to be
+ 1:1 mapped to the BARs, and the second is the
+ offset from be base of the BAR (which would be
+ non-zero if you had 2 or more devices mapped off
+ the same BAR)
+
+ ranges allows the address mapping to be described
+ in a way that the OS can interpret without
+ requiring custom device driver code.
+
+This is an example which is used on FalconFalls:
+------------------------------------------------
+ i2c-controller@b,2 {
+ #address-cells = <2>;
+ #size-cells = <1>;
+ compatible = "pci8086,2e68.2",
+ "pci8086,2e68",
+ "pciclass,ff0000",
+ "pciclass,ff00";
+
+ reg = <0x15a00 0x0 0x0 0x0 0x0>;
+ interrupts = <16 1>;
+
+ /* as described by Grant, the first number in the group of
+ * three is the bar number followed by the 64bit bar address
+ * followed by size of the mapping. The bar address
+ * requires also a valid translation in parents ranges
+ * property.
+ */
+ ranges = <0 0 0x02000000 0 0xdffe0500 0x100
+ 1 0 0x02000000 0 0xdffe0600 0x100
+ 2 0 0x02000000 0 0xdffe0700 0x100>;
+
+ i2c@0 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ compatible = "intel,ce4100-i2c-controller";
+
+ /* The first number in the reg property is the
+ * number of the bar
+ */
+ reg = <0 0 0x100>;
+
+ /* This I2C controller has no devices */
+ };
+
+ i2c@1 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ compatible = "intel,ce4100-i2c-controller";
+ reg = <1 0 0x100>;
+
+ /* This I2C controller has one gpio controller */
+ gpio@26 {
+ #gpio-cells = <2>;
+ compatible = "ti,pcf8575";
+ reg = <0x26>;
+ gpio-controller;
+ };
+ };
+
+ i2c@2 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ compatible = "intel,ce4100-i2c-controller";
+ reg = <2 0 0x100>;
+
+ gpio@26 {
+ #gpio-cells = <2>;
+ compatible = "ti,pcf8575";
+ reg = <0x26>;
+ gpio-controller;
+ };
+ };
+ };
diff --git a/Documentation/devicetree/bindings/x86/ce4100.txt b/Documentation/devicetree/bindings/x86/ce4100.txt
new file mode 100644
index 000000000000..b49ae593a60b
--- /dev/null
+++ b/Documentation/devicetree/bindings/x86/ce4100.txt
@@ -0,0 +1,38 @@
+CE4100 Device Tree Bindings
+---------------------------
+
+The CE4100 SoC uses for in core peripherals the following compatible
+format: <vendor>,<chip>-<device>.
+Many of the "generic" devices like HPET or IO APIC have the ce4100
+name in their compatible property because they first appeared in this
+SoC.
+
+The CPU node
+------------
+ cpu@0 {
+ device_type = "cpu";
+ compatible = "intel,ce4100";
+ reg = <0>;
+ lapic = <&lapic0>;
+ };
+
+The reg property describes the CPU number. The lapic property points to
+the local APIC timer.
+
+The SoC node
+------------
+
+This node describes the in-core peripherals. Required property:
+ compatible = "intel,ce4100-cp";
+
+The PCI node
+------------
+This node describes the PCI bus on the SoC. Its property should be
+ compatible = "intel,ce4100-pci", "pci";
+
+If the OS is using the IO-APIC for interrupt routing then the reported
+interrupt numbers for devices is no longer true. In order to obtain the
+correct interrupt number, the child node which represents the device has
+to contain the interrupt property. Besides the interrupt property it has
+to contain at least the reg property containing the PCI bus address and
+compatible property according to "PCI Bus Binding Revision 2.1".
diff --git a/Documentation/devicetree/bindings/x86/interrupt.txt b/Documentation/devicetree/bindings/x86/interrupt.txt
new file mode 100644
index 000000000000..8b0efb097e60
--- /dev/null
+++ b/Documentation/devicetree/bindings/x86/interrupt.txt
@@ -0,0 +1,29 @@
+Interrupt chips
+---------------
+
+* Intel I/O Advanced Programmable Interrupt Controller (IO APIC)
+
+ Required properties:
+ --------------------
+ compatible = "intel,ce4100-ioapic";
+ #interrupt-cells = <2>;
+
+ Device's interrupt property:
+
+ interrupts = <P S>;
+
+ The first number (P) represents the interrupt pin which is wired to the
+ IO APIC. The second number (S) represents the sense of interrupt which
+ should be configured and can be one of:
+ 0 - Edge Rising
+ 1 - Level Low
+ 2 - Level High
+ 3 - Edge Falling
+
+* Local APIC
+ Required property:
+
+ compatible = "intel,ce4100-lapic";
+
+ This node is currently unused by Linux as the address of the local APIC
+ read from a MSR.
diff --git a/Documentation/devicetree/bindings/x86/timer.txt b/Documentation/devicetree/bindings/x86/timer.txt
new file mode 100644
index 000000000000..c688af58e3bd
--- /dev/null
+++ b/Documentation/devicetree/bindings/x86/timer.txt
@@ -0,0 +1,6 @@
+Timers
+------
+
+* High Precision Event Timer (HPET)
+ Required property:
+ compatible = "intel,ce4100-hpet";
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