SPARC/LEON: added support for selecting Timer Core and Timer within core

The ability to select Timer Core and Timer instance for system clock
makes it possible for multiple AMP systems to coexist.
Signed-off-by: NDaniel Hellstrom <daniel@gaisler.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

arch/sparc/kernel/leon_kernel.c

@@ -32,6 +32,7 @@ int leon_debug_irqout;
 static int dummy_master_l10_counter;
 
 unsigned long leon3_gptimer_irq; /* interrupt controller irq number */
+unsigned long leon3_gptimer_idx; /* Timer Index (0..6) within Timer Core */
 unsigned int sparc_leon_eirq;
 #define LEON_IMASK ((&leon3_irqctrl_regs->mask[0]))
 
@@ -105,10 +106,11 @@ static void leon_disable_irq(unsigned int irq_nr)
 void __init leon_init_timers(irq_handler_t counter_fn)
 {
 	int irq;
-	struct device_node *rootnp, *np;
+	struct device_node *rootnp, *np, *nnp;
 	struct property *pp;
 	int len;
 	int cpu, icsel;
+	int ampopts;
 
 	leondebug_irq_disable = 0;
 	leon_debug_irqout = 0;
@@ -131,30 +133,52 @@ void __init leon_init_timers(irq_handler_t counter_fn)
 	leon3_irqctrl_regs = *(struct leon3_irqctrl_regs_map **)pp->value;
 
 	/* Find GPTIMER Timer Registers base address otherwise bail out. */
-	np = of_find_node_by_name(rootnp, "GAISLER_GPTIMER");
-	if (!np) {
-		np = of_find_node_by_name(np, "01_011");
-		if (!np)
-			goto bad;
-	}
-	pp = of_find_property(np, "reg", &len);
-	if (!pp)
-		goto bad;
-	leon3_gptimer_regs = *(struct leon3_gptimer_regs_map **)pp->value;
-	pp = of_find_property(np, "interrupts", &len);
-	if (!pp)
-		goto bad;
-	leon3_gptimer_irq = *(unsigned int *)pp->value;
+	nnp = rootnp;
+	do {
+		np = of_find_node_by_name(nnp, "GAISLER_GPTIMER");
+		if (!np) {
+			np = of_find_node_by_name(nnp, "01_011");
+			if (!np)
+				goto bad;
+		}
+
+		ampopts = 0;
+		pp = of_find_property(np, "ampopts", &len);
+		if (pp) {
+			ampopts = *(int *)pp->value;
+			if (ampopts == 0) {
+				/* Skip this instance, resource already
+				 * allocated by other OS */
+				nnp = np;
+				continue;
+			}
+		}
+
+		/* Select Timer-Instance on Timer Core. Default is zero */
+		leon3_gptimer_idx = ampopts & 0x7;
+
+		pp = of_find_property(np, "reg", &len);
+		if (pp)
+			leon3_gptimer_regs = *(struct leon3_gptimer_regs_map **)
+						pp->value;
+		pp = of_find_property(np, "interrupts", &len);
+		if (pp)
+			leon3_gptimer_irq = *(unsigned int *)pp->value;
+	} while (0);
 
 	if (leon3_gptimer_regs && leon3_irqctrl_regs && leon3_gptimer_irq) {
-		LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[0].val, 0);
-		LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[0].rld,
-				      (((1000000 / HZ) - 1)));
-		LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[0].ctrl, 0);
+		LEON3_BYPASS_STORE_PA(
+			&leon3_gptimer_regs->e[leon3_gptimer_idx].val, 0);
+		LEON3_BYPASS_STORE_PA(
+			&leon3_gptimer_regs->e[leon3_gptimer_idx].rld,
+			(((1000000 / HZ) - 1)));
+		LEON3_BYPASS_STORE_PA(
+			&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl, 0);
 
 #ifdef CONFIG_SMP
 		leon_percpu_timer_dev[0].start = (int)leon3_gptimer_regs;
-		leon_percpu_timer_dev[0].irq = leon3_gptimer_irq+1;
+		leon_percpu_timer_dev[0].irq = leon3_gptimer_irq + 1 +
+					       leon3_gptimer_idx;
 
 		if (!(LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->config) &
 		      (1<<LEON3_GPTIMER_SEPIRQ))) {
@@ -162,9 +186,13 @@ void __init leon_init_timers(irq_handler_t counter_fn)
 			BUG();
 		}
 
-		LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[1].val, 0);
-		LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[1].rld, (((1000000/HZ) - 1)));
-		LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[1].ctrl, 0);
+		LEON3_BYPASS_STORE_PA(
+			&leon3_gptimer_regs->e[leon3_gptimer_idx+1].val, 0);
+		LEON3_BYPASS_STORE_PA(
+			&leon3_gptimer_regs->e[leon3_gptimer_idx+1].rld,
+			(((1000000/HZ) - 1)));
+		LEON3_BYPASS_STORE_PA(
+			&leon3_gptimer_regs->e[leon3_gptimer_idx+1].ctrl, 0);
 # endif
 
 		/*
@@ -184,7 +212,7 @@ void __init leon_init_timers(irq_handler_t counter_fn)
 		goto bad;
 	}
 
-	irq = request_irq(leon3_gptimer_irq,
+	irq = request_irq(leon3_gptimer_irq+leon3_gptimer_idx,
 			  counter_fn,
 			  (IRQF_DISABLED | SA_STATIC_ALLOC), "timer", NULL);
 
@@ -216,13 +244,13 @@ void __init leon_init_timers(irq_handler_t counter_fn)
 # endif
 
 	if (leon3_gptimer_regs) {
-		LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[0].ctrl,
+		LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl,
 				      LEON3_GPTIMER_EN |
 				      LEON3_GPTIMER_RL |
 				      LEON3_GPTIMER_LD | LEON3_GPTIMER_IRQEN);
 
 #ifdef CONFIG_SMP
-		LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[1].ctrl,
+		LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx+1].ctrl,
 				      LEON3_GPTIMER_EN |
 				      LEON3_GPTIMER_RL |
 				      LEON3_GPTIMER_LD |