ARM: omap: convert wakeupgen to stacked domains

OMAP4/5 has been (ab)using the gic_arch_extn to provide
wakeup from suspend, and it makes a lot of sense to convert
this code to use stacked domains instead.

This patch does just this, updating the DT files to actually
reflect what the HW provides.

BIG FAT WARNING: because the DTs were so far lying by not
exposing the WUGEN HW block, kernels with this patch applied
won't have any suspend-resume facility when booted with old DTs,
and old kernels with updated DTs won't even boot.

On a platform with this patch applied, the system looks like
this:

root@bacon-fat:~# cat /proc/interrupts
            CPU0       CPU1
 16:          0          0     WUGEN  37  gp_timer
 19:     233799     155916       GIC  27  arch_timer
 23:          0          0     WUGEN   9  l3-dbg-irq
 24:          1          0     WUGEN  10  l3-app-irq
 27:        282          0     WUGEN  13  omap-dma-engine
 44:          0          0  4ae10000.gpio  13  DMA
294:          0          0     WUGEN  20  gpmc
297:        506          0     WUGEN  56  48070000.i2c
298:          0          0     WUGEN  57  48072000.i2c
299:          0          0     WUGEN  61  48060000.i2c
300:          0          0     WUGEN  62  4807a000.i2c
301:          8          0     WUGEN  60  4807c000.i2c
308:       2439          0     WUGEN  74  OMAP UART2
312:        362          0     WUGEN  83  mmc2
313:        502          0     WUGEN  86  mmc0
314:         13          0     WUGEN  94  mmc1
350:          0          0      PRCM  pinctrl, pinctrl
406:   35155709          0       GIC 109  ehci_hcd:usb1
407:          0          0     WUGEN   7  palmas
409:          0          0     WUGEN 119  twl6040
410:          0          0   twl6040   5  twl6040_irq_ready
411:          0          0   twl6040   0  twl6040_irq_th
IPI0:          0          1  CPU wakeup interrupts
IPI1:          0          0  Timer broadcast interrupts
IPI2:      95334     902334  Rescheduling interrupts
IPI3:          0          0  Function call interrupts
IPI4:        479        648  Single function call interrupts
IPI5:          0          0  CPU stop interrupts
IPI6:          0          0  IRQ work interrupts
IPI7:          0          0  completion interrupts
Err:          0

Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/1426088629-15377-8-git-send-email-marc.zyngier@arm.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

arch/arm/mach-omap2/omap4-common.c

@@ -241,26 +241,26 @@ static int __init omap4_sar_ram_init(void)
 }
 omap_early_initcall(omap4_sar_ram_init);
 
-static const struct of_device_id gic_match[] = {
-	{ .compatible = "arm,cortex-a9-gic", },
-	{ .compatible = "arm,cortex-a15-gic", },
+static const struct of_device_id intc_match[] = {
+	{ .compatible = "ti,omap4-wugen-mpu", },
+	{ .compatible = "ti,omap5-wugen-mpu", },
 	{ },
 };
 
-static struct device_node *gic_node;
+static struct device_node *intc_node;
 
 unsigned int omap4_xlate_irq(unsigned int hwirq)
 {
 	struct of_phandle_args irq_data;
 	unsigned int irq;
 
-	if (!gic_node)
-		gic_node = of_find_matching_node(NULL, gic_match);
+	if (!intc_node)
+		intc_node = of_find_matching_node(NULL, intc_match);
 
-	if (WARN_ON(!gic_node))
+	if (WARN_ON(!intc_node))
 		return hwirq;
 
-	irq_data.np = gic_node;
+	irq_data.np = intc_node;
 	irq_data.args_count = 3;
 	irq_data.args[0] = 0;
 	irq_data.args[1] = hwirq - OMAP44XX_IRQ_GIC_START;
@@ -277,6 +277,12 @@ void __init omap_gic_of_init(void)
 {
 	struct device_node *np;
 
+	intc_node = of_find_matching_node(NULL, intc_match);
+	if (WARN_ON(!intc_node)) {
+		pr_err("No WUGEN found in DT, system will misbehave.\n");
+		pr_err("UPDATE YOUR DEVICE TREE!\n");
+	}
+
 	/* Extract GIC distributor and TWD bases for OMAP4460 ROM Errata WA */
 	if (!cpu_is_omap446x())
 		goto skip_errata_init;
@@ -290,6 +296,5 @@ void __init omap_gic_of_init(void)
 	WARN_ON(!twd_base);
 
 skip_errata_init:
-	omap_wakeupgen_init();
 	irqchip_init();
 }