From f8496c893debead6b5a75912946f048ed8c952a2 Mon Sep 17 00:00:00 2001
From: Hoegeun Kwon <hoegeun.kwon@samsung.com>
Date: Wed, 26 Jul 2023 20:32:55 +0900
Subject: [PATCH] soc: sifive: ccache: Add delay after flush

Problems with cache flush at resolutions exceeding FUD and with inno
hdmi driver. It runs a cache flush and requires a delay. So add delay
after cache flush.

Change-Id: Id8b1398dcce04851577912e6c1dfd4a2b580a043
Signed-off-by: Hoegeun Kwon <hoegeun.kwon@samsung.com>
---
 drivers/soc/sifive/sifive_ccache.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/soc/sifive/sifive_ccache.c b/drivers/soc/sifive/sifive_ccache.c
index 79de3179d066..73c39c349d36 100644
--- a/drivers/soc/sifive/sifive_ccache.c
+++ b/drivers/soc/sifive/sifive_ccache.c
@@ -9,6 +9,9 @@
 #define pr_fmt(fmt) "CCACHE: " fmt
 
 #include <linux/debugfs.h>
+#ifdef CONFIG_STARFIVE_INNO_HDMI
+#include <linux/delay.h>
+#endif
 #include <linux/interrupt.h>
 #include <linux/of_irq.h>
 #include <linux/of_address.h>
@@ -159,6 +162,13 @@ void sifive_flush64_range(unsigned long start, unsigned long len)
 		writeq(line, ccache_base + SIFIVE_FLUSH64);
 		mb();
 	}
+#ifdef CONFIG_STARFIVE_INNO_HDMI
+	/*
+	 * Problems with cache flush at resolutions exceeding FUD.
+	 * It runs a cache flush and requires a delay.
+	 */
+	udelay(700);
+#endif
 }
 EXPORT_SYMBOL_GPL(sifive_flush64_range);
 #endif
-- 
2.34.1