[PATCH] ata: add AMD Seattle platform driver

AMD Seattle SATA controller mostly conforms to AHCI interface with some
special register to control SGPIO interface. In the case of an AHCI
controller, the SGPIO feature is ideally implemented using the
"Enclosure Management" register of the AHCI controller, but those
registeres are not implemented in the Seattle SoC. Instead SoC
(Rev B0 onwards) provides a 32-bit SGPIO control register which should
be programmed to control the activity, locate and fault LEDs.

The driver is based on ahci_platform driver.

Signed-off-by: Brijesh Singh <redacted>
CC: robh+dt at kernel.org
CC: pawel.moll at arm.com
CC: mark.rutland at arm.com
CC: ijc+devicetree at hellion.org.uk
CC: galak at codeaurora.org
CC: tj at kernel.org
CC: devicetree at vger.kernel.org
CC: linux-ide at vger.kernel.org
---
 .../devicetree/bindings/ata/sata-seattle.txt       |  34 ++++
 drivers/ata/Kconfig                                |   8 +
 drivers/ata/Makefile                               |   1 +
 drivers/ata/ahci_seattle.c                         | 226 +++++++++++++++++++++
 4 files changed, 269 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/ata/sata-seattle.txt
 create mode 100644 drivers/ata/ahci_seattle.c

diff --git a/Documentation/devicetree/bindings/ata/sata-seattle.txt b/Documentation/devicetree/bindings/ata/sata-seattle.txt
new file mode 100644
index 0000000..5ad46b7
--- /dev/null
+++ b/Documentation/devicetree/bindings/ata/sata-seattle.txt

@@ -0,0 +1,34 @@
+* AHCI SATA Controller
+
+SATA nodes are defined to describe on-chip Serial ATA controllers.
+The AMD Seattle SATA controller mostly conforms to the AHCI interface
+with some special SGPIO register to contro activity LED interfaces.
+
+In the case of an AHCI controller, the SGPIO feature is ideally implemented
+using the "Enclosure Management" register of the AHCI controller, but
+those registeres are not implemented in the Seattle SoC.
+
+Each SATA controller should have its own node.
+
+
+Required properties:
+- compatible        : compatible string should be "amd,seattle-ahci".
+- interrupts        : <interrupt mapping for SATA IRQ>
+- reg               : <registers mapping>
+
+Optional properties:
+- dma-coherent      : Present if dma operations are coherent
+- clocks            : a list of phandle + clock specifier pairs
+- target-supply     : regulator for SATA target power
+- phys              : reference to the SATA PHY node
+- phy-names         : must be "sata-phy"
+
+Examples:
+        sata0 at e0300000 {
+		compatible = "amd,seattle-ahci";
+		reg = <0x0 0xe0300000 0x0 0xf0000>, <0x0 0xe0000078 0x0 0x1>;