From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: [PATCH 08/21] riscv: dma-mapping: only invalidate after DMA, not flush Date: Mon, 27 Mar 2023 14:13:04 +0200 Message-ID: <20230327121317.4081816-9-arnd@kernel.org> References: <20230327121317.4081816-1-arnd@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=V6hBBmTUb/14a+F7Ok//C2wtII3J+8SfYsLhIka9szo=; b=IZQYML0HGy9Zlt cucFH8WqdX8rh0HHOJTGu3CDVCmswa7wxRmdsNLwapef1tGfe/3AGR+vbxCGV821dZ0NgcCe5p9GC 7GaxtQM7y91dRWqmfEnovtod9cgfIOZM9dy0yLYU2lHeypdoa0m3+gZYrSepah4vnxSJL0iOAla4i KyV+9VJwA23uS3pn6OepREDvF7yeSpaCDh2f8MNnQhfWq9puZbXM/CSyRskHDVUeQ6q2LlViFy8Ss wVlRVF8tu48Hlf30xaWFrVKhGKLf8dGOUxMQZPo8qQRjOcS2itHjKT7Q8VuVYmW/tNJsFVlSiEDdM BHs3AOPCutGmey6x5ZjA==; DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1679919307; bh=p+eG9OtxIwlFEHuBl1BynARl6RQHBxG84PbOJSDaMSg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=k7yTj16MC4QC0lUkI+OlRgN70GEfUAXZsHUm34awwsfDq+uuBVpGn8XzMpAYzrKep rzfZf9IvuTrt/evwGGuCXfuT5QwwzcXZODB9YgjYpxv0iZgT9rwRfHG1vVFKHMnR80 WkjKXapkPoQqpX0z8bvvlpG0YOBt+p7Spw/IdU0XpPUFOYiASiKd39EeZPyxyEYUJn 9ZY055tF4c7BVKMQhNCmNKfo+NgnV/grwYyrPuAwvgV7tJNlhsepLbNs91InZGtrtI 0UOObEmqhXtHeujJTAybyrsno6jtIGCIZbfee+GXSUa8z2HvG7G/GO5AeAihPvul14 jCOgl+Q3LDa9w== In-Reply-To: <20230327121317.4081816-1-arnd@kernel.org> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+glpr-linux-riscv=m.gmane-mx.org@lists.infradead.org To: linux-kernel@vger.kernel.org Cc: Arnd Bergmann , Vineet Gupta , Russell King , Neil Armstrong , Linus Walleij , Catalin Marinas , Will Deacon , Guo Ren , Brian Cain , Geert Uytterhoeven , Michal Simek , Thomas Bogendoerfer , Dinh Nguyen , Stafford Horne , Helge Deller , Michael Ellerman , Christophe Leroy , Paul Walmsley , Palmer Dabbelt , Rich Felker , John Paul Adrian Glaubitz , "David S. Miller" , Max Filippov From: Arnd Bergmann No other architecture intentionally writes back dirty cache lines into a buffer that a device has just finished writing into. If the cache is clean, this has no effect at all, but if a cacheline in the buffer has actually been written by the CPU, there is a drive bug that is likely made worse by overwriting that buffer. Signed-off-by: Arnd Bergmann --- arch/riscv/mm/dma-noncoherent.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/riscv/mm/dma-noncoherent.c b/arch/riscv/mm/dma-noncoherent.c index d919efab6eba..640f4c496d26 100644 --- a/arch/riscv/mm/dma-noncoherent.c +++ b/arch/riscv/mm/dma-noncoherent.c @@ -42,7 +42,7 @@ void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size, break; case DMA_FROM_DEVICE: case DMA_BIDIRECTIONAL: - ALT_CMO_OP(flush, vaddr, size, riscv_cbom_block_size); + ALT_CMO_OP(inval, vaddr, size, riscv_cbom_block_size); break; default: break; -- 2.39.2