From cf141ae989e2ff119cd320326da5923b480d1641 Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@lst.de>
Date: Tue, 8 Sep 2020 19:24:00 +0200
Subject: [PATCH] ARM/keystone: move the DMA offset handling under ifdef
 CONFIG_ARM_LPAE

The DMA offset notifier can only be used if PHYS_OFFSET is at least
KEYSTONE_HIGH_PHYS_START, which can't be represented by a 32-bit
phys_addr_t.  Currently the code compiles fine despite that, a pending
change to the DMA offset handling would create a compiler warning for
this case.  Add an ifdef to not compile the code except for LPAE
configs.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
---
 arch/arm/mach-keystone/keystone.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/arm/mach-keystone/keystone.c b/arch/arm/mach-keystone/keystone.c
index 638808c4e1224..dcd031ba84c2e 100644
--- a/arch/arm/mach-keystone/keystone.c
+++ b/arch/arm/mach-keystone/keystone.c
@@ -24,6 +24,7 @@
 
 #include "keystone.h"
 
+#ifdef CONFIG_ARM_LPAE
 static unsigned long keystone_dma_pfn_offset __read_mostly;
 
 static int keystone_platform_notifier(struct notifier_block *nb,
@@ -48,14 +49,17 @@ static int keystone_platform_notifier(struct notifier_block *nb,
 static struct notifier_block platform_nb = {
 	.notifier_call = keystone_platform_notifier,
 };
+#endif /* CONFIG_ARM_LPAE */
 
 static void __init keystone_init(void)
 {
+#ifdef CONFIG_ARM_LPAE
 	if (PHYS_OFFSET >= KEYSTONE_HIGH_PHYS_START) {
 		keystone_dma_pfn_offset = PFN_DOWN(KEYSTONE_HIGH_PHYS_START -
 						   KEYSTONE_LOW_PHYS_START);
 		bus_register_notifier(&platform_bus_type, &platform_nb);
 	}
+#endif
 	keystone_pm_runtime_init();
 }
 
-- 
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