ipq806x: set wan and wifi cpu affinity

At the moment by default all interrupts are assigned to core0.
Due to absence of implemented hardware NAT, balancing irq load between cpu cores provides noticeable performance gain - 10-30% depending on usage template.

With this script we are adjusting wan and wlan cpu affinity on different cores during boot.

After this change:
*ipq4019 (has 4 cores (core0-core3))
 - wan interrupt is assigned to core1
 - 2.4 ghz wifi - to core2
 - 5 ghz wifi - to core3

*ipq8064/5 (has 2 cores (core0 and core1))
 - wan interrupt is assigned to core1
 - 2.4ghz wifi - to core1

Signed-off-by: Pavel Kubelun <be.dissent@gmail.com>

target/linux/ipq806x/base-files/etc/init.d/set_cpu_affinity

@@ -0,0 +1,55 @@
+#!/bin/sh /etc/rc.common
+
+START=99
+
+set_irq_affinity() {
+	local name="$1"
+	local val="$2"
+
+case "$name" in
+wifi0)
+  	local irq_wifi0=`grep -E -m1 'qcom-pcie-msi' /proc/interrupts | cut -d: -f1 | tail -n1 | tr -d ' '`
+	[ -n "$irq_wifi0" ] || echo "$name irq not found."
+	echo "$val" > "/proc/irq/$irq_wifi0/smp_affinity"
+	;;
+wifi1)
+  	local irq_wifi1=`grep -E -m2 'qcom-pcie-msi' /proc/interrupts | cut -d: -f1 | tail -n1 | tr -d ' '`
+	[ -n "$irq_wifi1" ] || echo "$name irq not found."
+	echo "$val" > "/proc/irq/$irq_wifi1/smp_affinity"
+	;;
+*)
+  	local irq=`grep -m 1 "$name" /proc/interrupts | cut -d: -f1 | sed 's, *,,'`
+	[ -n "$irq" ] || echo "$name irq not found."
+	echo "$val" > "/proc/irq/$irq/smp_affinity"
+	;;
+esac
+}
+
+start() {
+
+local board_name="cat /tmp/sysinfo/board_name"
+
+case "$board_name" in
+fritz4040)
+  	set_irq_affinity eth1 2
+	set_irq_affinity wifi0 4
+	set_irq_affinity wifi1 8
+	;;
+ap148 |\
+c2600 |\
+db149 |\
+d7800 |\
+ea8500 |\
+nbg6817 |\
+r7500 |\
+r7500v2 |\
+r7800 |\
+vr2600v)
+  	set_irq_affinity eth0 2
+	set_irq_affinity wifi1 2
+	;;
+*)
+	echo "Unsupported hardware. CPU affinity is not adjusted."
+	;;
+esac
+}