Re: [PATCH 2/3] ARM/keystone: move the DMA offset handling under ifdef CONFIG_ARM_LPAE

From: Robin Murphy
Date: Fri Sep 11 2020 - 07:12:54 EST

On 2020-09-10 06:40, Christoph Hellwig wrote:
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

Seems reasonable - once again I wonder whether this notifier is really needed any more since "dma-ranges" should now be handled properly for PCI devices as well, but that's not something to worry about in this series.

Reviewed-by: Robin Murphy <robin.murphy@xxxxxxx>

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
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 638808c4e12247..dcd031ba84c2e0 100644
--- a/arch/arm/mach-keystone/keystone.c
+++ b/arch/arm/mach-keystone/keystone.c
@@ -24,6 +24,7 @@
#include "keystone.h"
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)
keystone_dma_pfn_offset = PFN_DOWN(KEYSTONE_HIGH_PHYS_START -
bus_register_notifier(&platform_bus_type, &platform_nb);