ARM: firmware: add AFTR mode support to firmware do_idle method

On some platforms (i.e. EXYNOS ones) more than one idle mode is
available and we need to distinguish them in firmware do_idle method.

Add mode parameter to do_idle firmware method and AFTR mode support
to EXYNOS do_idle implementation.

This change is a preparation for adding secure firmware support to
EXYNOS cpuidle driver.

This patch shouldn't cause any functionality changes.

Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

arch/arm/mach-exynos/firmware.c

@@ -28,9 +28,15 @@
 #define EXYNOS_BOOT_ADDR	0x8
 #define EXYNOS_BOOT_FLAG	0xc
 
-static int exynos_do_idle(void)
+static int exynos_do_idle(unsigned long mode)
 {
-	exynos_smc(SMC_CMD_SLEEP, 0, 0, 0);
+	switch (mode) {
+	case FW_DO_IDLE_AFTR:
+		exynos_smc(SMC_CMD_CPU0AFTR, 0, 0, 0);
+		break;
+	case FW_DO_IDLE_SLEEP:
+		exynos_smc(SMC_CMD_SLEEP, 0, 0, 0);
+	}
 	return 0;
 }