Feedback-ID: ifd894703:Fastmail
From:   Jiaxun Yang <jiaxun.yang@flygoat.com>
To:     linux-mips@vger.kernel.org
Cc:     linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org,
        tsbogend@alpha.franken.de, mpe@ellerman.id.au,
        paul.walmsley@sifive.com, palmer@dabbelt.com, robh+dt@kernel.org,
        hch@lst.de, m.szyprowski@samsung.com, robin.murphy@arm.com,
        linux-riscv@lists.infradead.org,
        Jiaxun Yang <jiaxun.yang@flygoat.com>
Subject: [PATCH 2/3] riscv: Set dma_default_coherent to true
Date:   Wed, 22 Feb 2023 13:37:11 +0000
Message-Id: <20230222133712.8079-3-jiaxun.yang@flygoat.com>
In-Reply-To: <20230222133712.8079-1-jiaxun.yang@flygoat.com>
References: <20230222133712.8079-1-jiaxun.yang@flygoat.com>
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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@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)