[PATCH 3/4] powerpc/64: Limit ZONE_DMA32 to 4GiB in swiotlb_detect_4g()
From: Scott Wood <hidden>
Date: 2014-08-08 23:41:12
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
A DMA zone is still needed with swiotlb, for coherent allocations. This doesn't affect platforms that don't use swiotlb or that don't call swiotlb_detect_4g(). Signed-off-by: Scott Wood <redacted> Cc: Shaohui Xie <redacted> --- arch/powerpc/kernel/dma-swiotlb.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/kernel/dma-swiotlb.c b/arch/powerpc/kernel/dma-swiotlb.c
index bd1a2ab..7359797 100644
--- a/arch/powerpc/kernel/dma-swiotlb.c
+++ b/arch/powerpc/kernel/dma-swiotlb.c@@ -106,10 +106,14 @@ int __init swiotlb_setup_bus_notifier(void) return 0; } -void swiotlb_detect_4g(void) +void __init swiotlb_detect_4g(void) { - if ((memblock_end_of_DRAM() - 1) > 0xffffffff) + if ((memblock_end_of_DRAM() - 1) > 0xffffffff) { ppc_swiotlb_enable = 1; +#ifdef CONFIG_ZONE_DMA32 + limit_zone_pfn(ZONE_DMA32, (1ULL << 32) >> PAGE_SHIFT); +#endif + } } static int __init swiotlb_late_init(void)
--
1.9.1