[PATCH 2/3] riscv: Set dma_default_coherent to true

Jiaxun Yang jiaxun.yang at flygoat.com
Wed Feb 22 05:37:11 PST 2023


For riscv our assumption is unless a device states it is non-coherent,
we take it to be DMA coherent.

For devicetree probed devices that have been true since very begining
with OF_DMA_DEFAULT_COHERENT selected.

Signed-off-by: Jiaxun Yang <jiaxun.yang at flygoat.com>
---
 arch/riscv/kernel/setup.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
index 376d2827e736..34b371180976 100644
--- a/arch/riscv/kernel/setup.c
+++ b/arch/riscv/kernel/setup.c
@@ -300,6 +300,9 @@ void __init setup_arch(char **cmdline_p)
 	riscv_init_cbom_blocksize();
 	riscv_fill_hwcap();
 	apply_boot_alternatives();
+#ifdef CONFIG_RISCV_DMA_NONCOHERENT
+	dma_default_coherent = true;
+#endif
 	if (IS_ENABLED(CONFIG_RISCV_ISA_ZICBOM) &&
 	    riscv_isa_extension_available(NULL, ZICBOM))
 		riscv_noncoherent_supported();
-- 
2.37.1 (Apple Git-137.1)




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