From 2ef5eb848f862ede38e5a7cd3656b5501104acd7 Mon Sep 17 00:00:00 2001 From: Florian Fainelli Date: Thu, 18 Mar 2021 21:03:33 -0700 Subject: [PATCH] ARM: Qualify enabling of swiotlb_init() commit fcf044891c84e38fc90eb736b818781bccf94e38 upstream. We do not need a SWIOTLB unless we have DRAM that is addressable beyond the arm_dma_limit. Compare max_pfn with arm_dma_pfn_limit to determine whether we do need a SWIOTLB to be initialized. Fixes: 96ea560103b0 ("arm: use swiotlb for bounce buffering on LPAE configs") Signed-off-by: Florian Fainelli Signed-off-by: Konrad Rzeszutek Wilk Signed-off-by: Greg Kroah-Hartman --- arch/arm/mm/init.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c index 0804a6af4a3b7..5a3641b5ec2cd 100644 --- a/arch/arm/mm/init.c +++ b/arch/arm/mm/init.c @@ -469,7 +469,11 @@ static void __init free_highpages(void) void __init mem_init(void) { #ifdef CONFIG_ARM_LPAE - swiotlb_init(1); + if (swiotlb_force == SWIOTLB_FORCE || + max_pfn > arm_dma_pfn_limit) + swiotlb_init(1); + else + swiotlb_force = SWIOTLB_NO_FORCE; #endif set_max_mapnr(pfn_to_page(max_pfn) - mem_map); -- 2.39.5