From fcf044891c84e38fc90eb736b818781bccf94e38 Mon Sep 17 00:00:00 2001 From: Florian Fainelli Date: Thu, 18 Mar 2021 21:03:33 -0700 Subject: ARM: Qualify enabling of swiotlb_init() 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: ad3c7b18c5b3 ("arm: use swiotlb for bounce buffering on LPAE configs") Signed-off-by: Florian Fainelli Signed-off-by: Konrad Rzeszutek Wilk --- arch/arm/mm/init.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'arch/arm/mm/init.c') diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c index 828a2561b229..8356bf1daa28 100644 --- a/arch/arm/mm/init.c +++ b/arch/arm/mm/init.c @@ -301,7 +301,11 @@ 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); -- cgit v1.2.3