ARM: highbank: add coherent DMA setup

Some highbank DMA masters can support coherent (ACP) or non-coherent DMA.
This sets up dma_map_ops for masters which are configured for coherent DMA.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Signed-off-by: NMarek Szyprowski <m.szyprowski@samsung.com>

Documentation/devicetree/bindings/ata/ahci-platform.txt

@@ -8,6 +8,9 @@ Required properties:
 - interrupts        : <interrupt mapping for SATA IRQ>
 - reg               : <registers mapping>
 
+Optional properties:
+- dma-coherent      : Present if dma operations are coherent
+
 Example:
         sata@ffe08000 {
 		compatible = "calxeda,hb-ahci";

Documentation/devicetree/bindings/dma/arm-pl330.txt

@@ -9,6 +9,9 @@ Required properties:
     region.
   - interrupts: interrupt number to the cpu.
 
+Optional properties:
+- dma-coherent      : Present if dma operations are coherent
+
 Example:
 
 	pdma0: pdma@12680000 {

Documentation/devicetree/bindings/net/calxeda-xgmac.txt

@@ -6,6 +6,9 @@ Required properties:
 - interrupts : Should contain 3 xgmac interrupts. The 1st is main interrupt.
   The 2nd is pwr mgt interrupt. The 3rd is low power state interrupt.
 
+Optional properties:
+- dma-coherent      : Present if dma operations are coherent
+
 Example:
 
 ethernet@fff50000 {

arch/arm/boot/dts/highbank.dts

@@ -121,6 +121,7 @@
 			compatible = "calxeda,hb-ahci";
 			reg = <0xffe08000 0x10000>;
 			interrupts = <0 83 4>;
+			dma-coherent;
 		};
 
 		sdhci@ffe0e000 {

arch/arm/mach-highbank/highbank.c

@@ -15,6 +15,7 @@
  */
 #include <linux/clk.h>
 #include <linux/clkdev.h>
+#include <linux/dma-mapping.h>
 #include <linux/io.h>
 #include <linux/irq.h>
 #include <linux/irqdomain.h>
@@ -23,6 +24,7 @@
 #include <linux/of_platform.h>
 #include <linux/of_address.h>
 #include <linux/smp.h>
+#include <linux/amba/bus.h>
 
 #include <asm/cacheflush.h>
 #include <asm/smp_plat.h>
@@ -149,10 +151,60 @@ static void highbank_power_off(void)
 		cpu_do_idle();
 }
 
+static int highbank_platform_notifier(struct notifier_block *nb,
+				  unsigned long event, void *__dev)
+{
+	struct resource *res;
+	int reg = -1;
+	struct device *dev = __dev;
+
+	if (event != BUS_NOTIFY_ADD_DEVICE)
+		return NOTIFY_DONE;
+
+	if (of_device_is_compatible(dev->of_node, "calxeda,hb-ahci"))
+		reg = 0xc;
+	else if (of_device_is_compatible(dev->of_node, "calxeda,hb-sdhci"))
+		reg = 0x18;
+	else if (of_device_is_compatible(dev->of_node, "arm,pl330"))
+		reg = 0x20;
+	else if (of_device_is_compatible(dev->of_node, "calxeda,hb-xgmac")) {
+		res = platform_get_resource(to_platform_device(dev),
+					    IORESOURCE_MEM, 0);
+		if (res) {
+			if (res->start == 0xfff50000)
+				reg = 0;
+			else if (res->start == 0xfff51000)
+				reg = 4;
+		}
+	}
+
+	if (reg < 0)
+		return NOTIFY_DONE;
+
+	if (of_property_read_bool(dev->of_node, "dma-coherent")) {
+		writel(0xff31, sregs_base + reg);
+		set_dma_ops(dev, &arm_coherent_dma_ops);
+	} else
+		writel(0, sregs_base + reg);
+
+	return NOTIFY_OK;
+}
+
+static struct notifier_block highbank_amba_nb = {
+	.notifier_call = highbank_platform_notifier,
+};
+
+static struct notifier_block highbank_platform_nb = {
+	.notifier_call = highbank_platform_notifier,
+};
+
 static void __init highbank_init(void)
 {
 	pm_power_off = highbank_power_off;
 
+	bus_register_notifier(&platform_bus_type, &highbank_platform_nb);
+	bus_register_notifier(&amba_bustype, &highbank_amba_nb);
+
 	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
 }