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+Device State Configuration Registers
+------------------------------------
+
+TI C6X SoCs contain a region of miscellaneous registers which provide various
+function for SoC control or status. Details vary considerably among from SoC
+to SoC with no two being alike.
+
+In general, the Device State Configuraion Registers (DSCR) will provide one or
+more configuration registers often protected by a lock register where one or
+more key values must be written to a lock register in order to unlock the
+configuration register for writes. These configuration register may be used to
+enable (and disable in some cases) SoC pin drivers, select peripheral clock
+sources (internal or pin), etc. In some cases, a configuration register is
+write once or the individual bits are write once. In addition to device config,
+the DSCR block may provide registers which which are used to reset peripherals,
+provide device ID information, provide ethernet MAC addresses, as well as other
+miscellaneous functions.
+
+For device state control (enable/disable), each device control is assigned an
+id which is used by individual device drivers to control the state as needed.
+
+Required properties:
+
+- compatible: must be "ti,c64x+dscr"
+- reg: register area base and size
+
+Optional properties:
+
+ NOTE: These are optional in that not all SoCs will have all properties. For
+ SoCs which do support a given property, leaving the property out of the
+ device tree will result in reduced functionality or possibly driver
+ failure.
+
+- ti,dscr-devstat
+ offset of the devstat register
+
+- ti,dscr-silicon-rev
+ offset, start bit, and bitsize of silicon revision field
+
+- ti,dscr-rmii-resets
+ offset and bitmask of RMII reset field. May have multiple tuples if more
+ than one ethernet port is available.
+
+- ti,dscr-locked-regs
+ possibly multiple tuples describing registers which are write protected by
+ a lock register. Each tuple consists of the register offset, lock register
+ offsset, and the key value used to unlock the register.
+
+- ti,dscr-kick-regs
+ offset and key values of two "kick" registers used to write protect other
+ registers in DSCR. On SoCs using kick registers, the first key must be
+ written to the first kick register and the second key must be written to
+ the second register before other registers in the area are write-enabled.
+
+- ti,dscr-mac-fuse-regs
+ MAC addresses are contained in two registers. Each element of a MAC address
+ is contained in a single byte. This property has two tuples. Each tuple has
+ a register offset and four cells representing bytes in the register from
+ most significant to least. The value of these four cells is the MAC byte
+ index (1-6) of the byte within the register. A value of 0 means the byte
+ is unused in the MAC address.
+
+- ti,dscr-devstate-ctl-regs
+ This property describes the bitfields used to control the state of devices.
+ Each tuple describes a range of identical bitfields used to control one or
+ more devices (one bitfield per device). The layout of each tuple is:
+
+ start_id num_ids reg enable disable start_bit nbits
+
+ Where:
+ start_id is device id for the first device control in the range
+ num_ids is the number of device controls in the range
+ reg is the offset of the register holding the control bits
+ enable is the value to enable a device
+ disable is the value to disable a device (0xffffffff if cannot disable)
+ start_bit is the bit number of the first bit in the range
+ nbits is the number of bits per device control
+
+- ti,dscr-devstate-stat-regs
+ This property describes the bitfields used to provide device state status
+ for device states controlled by the DSCR. Each tuple describes a range of
+ identical bitfields used to provide status for one or more devices (one
+ bitfield per device). The layout of each tuple is:
+
+ start_id num_ids reg enable disable start_bit nbits
+
+ Where:
+ start_id is device id for the first device status in the range
+ num_ids is the number of devices covered by the range
+ reg is the offset of the register holding the status bits
+ enable is the value indicating device is enabled
+ disable is the value indicating device is disabled
+ start_bit is the bit number of the first bit in the range
+ nbits is the number of bits per device status
+
+- ti,dscr-privperm
+ Offset and default value for register used to set access privilege for
+ some SoC devices.
+
+
+Example:
+
+ device-state-config-regs@2a80000 {
+ compatible = "ti,c64x+dscr";
+ reg = <0x02a80000 0x41000>;
+
+ ti,dscr-devstat = <0>;
+ ti,dscr-silicon-rev = <8 28 0xf>;
+ ti,dscr-rmii-resets = <0x40020 0x00040000>;
+
+ ti,dscr-locked-regs = <0x40008 0x40004 0x0f0a0b00>;
+ ti,dscr-devstate-ctl-regs =
+ <0 12 0x40008 1 0 0 2
+ 12 1 0x40008 3 0 30 2
+ 13 2 0x4002c 1 0xffffffff 0 1>;
+ ti,dscr-devstate-stat-regs =
+ <0 10 0x40014 1 0 0 3
+ 10 2 0x40018 1 0 0 3>;
+
+ ti,dscr-mac-fuse-regs = <0x700 1 2 3 4
+ 0x704 5 6 0 0>;
+
+ ti,dscr-privperm = <0x41c 0xaaaaaaaa>;
+
+ ti,dscr-kick-regs = <0x38 0x83E70B13
+ 0x3c 0x95A4F1E0>;
+ };