irqchip/gic-v3: Use readl_relaxed_poll_timeout_atomic()

Replace the open coded register polling loop with
readl_relaxed_poll_timeout_atomic() which provides the same functionality.

Signed-off-by: Dawei Li <dawei.li@shingroup.cn>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240122085716.2999875-2-dawei.li@shingroup.cn

Author: Dawei Li

drivers/irqchip/irq-gic-v3.c

@@ -19,6 +19,7 @@
 #include <linux/percpu.h>
 #include <linux/refcount.h>
 #include <linux/slab.h>
+#include <linux/iopoll.h>
 
 #include <linux/irqchip.h>
 #include <linux/irqchip/arm-gic-common.h>
@@ -251,17 +252,13 @@ static inline void __iomem *gic_dist_base(struct irq_data *d)
 
 static void gic_do_wait_for_rwp(void __iomem *base, u32 bit)
 {
-	u32 count = 1000000;	/* 1s! */
+	u32 val;
+	int ret;
 
-	while (readl_relaxed(base + GICD_CTLR) & bit) {
-		count--;
-		if (!count) {
-			pr_err_ratelimited("RWP timeout, gone fishing\n");
-			return;
-		}
-		cpu_relax();
-		udelay(1);
-	}
+	ret = readl_relaxed_poll_timeout_atomic(base + GICD_CTLR, val, !(val & bit),
+						1, USEC_PER_SEC);
+	if (ret == -ETIMEDOUT)
+		pr_err_ratelimited("RWP timeout, gone fishing\n");
 }
 
 /* Wait for completion of a distributor change */
@@ -279,8 +276,8 @@ static void gic_redist_wait_for_rwp(void)
 static void gic_enable_redist(bool enable)
 {
 	void __iomem *rbase;
-	u32 count = 1000000;	/* 1s! */
 	u32 val;
+	int ret;
 
 	if (gic_data.flags & FLAGS_WORKAROUND_GICR_WAKER_MSM8996)
 		return;
@@ -301,16 +298,13 @@ static void gic_enable_redist(bool enable)
 			return;	/* No PM support in this redistributor */
 	}
 
-	while (--count) {
-		val = readl_relaxed(rbase + GICR_WAKER);
-		if (enable ^ (bool)(val & GICR_WAKER_ChildrenAsleep))
-			break;
-		cpu_relax();
-		udelay(1);
-	}
-	if (!count)
+	ret = readl_relaxed_poll_timeout_atomic(rbase + GICR_WAKER, val,
+						enable ^ (bool)(val & GICR_WAKER_ChildrenAsleep),
+						1, USEC_PER_SEC);
+	if (ret == -ETIMEDOUT) {
 		pr_err_ratelimited("redistributor failed to %s...\n",
 				   enable ? "wakeup" : "sleep");
+	}
 }
 
 /*