From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=crapouillou.net header.i=@crapouillou.net header.b="sqhSiRUn" Received: from aposti.net (aposti.net [89.234.176.197]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E6ED6106; Mon, 4 Dec 2023 06:04:37 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=crapouillou.net; s=mail; t=1701698645; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=EauQ2wrK+wrLp0dftTWFW30qJjPlPW+KVuBL537ybvE=; b=sqhSiRUnlnoXtZWveiRp1jISoIWmyTlvKkcLmp5C07pvU84zyl6Q7NTsW13auL+QliM2WW 9dKbELEL5y50o0nee7w61mwRwS8281vbiyKKMzADxg67OuPkfkADEvvCZGd3aM7S9YYVvl ZgkPq4XbNTsdIdVtknno/FA3aKeaRoY= From: Paul Cercueil To: Vinod Koul Cc: Lars-Peter Clausen , =?UTF-8?q?Nuno=20S=C3=A1?= , Michael Hennerich , dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, Paul Cercueil Subject: [PATCH 4/4] dmaengine: axi-dmac: Use only EOT interrupts when doing scatter-gather Date: Mon, 4 Dec 2023 15:03:52 +0100 Message-ID: <20231204140352.30420-5-paul@crapouillou.net> In-Reply-To: <20231204140352.30420-1-paul@crapouillou.net> References: <20231204140352.30420-1-paul@crapouillou.net> Precedence: bulk X-Mailing-List: dmaengine@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Spam: Yes Instead of notifying userspace in the end-of-transfer (EOT) interrupt and program the hardware in the start-of-transfer (SOT) interrupt, we can do both things in the EOT, allowing us to mask the SOT, and halve the number of interrupts sent by the HDL core. Signed-off-by: Paul Cercueil --- drivers/dma/dma-axi-dmac.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/dma/dma-axi-dmac.c b/drivers/dma/dma-axi-dmac.c index 5109530b66de..beed91a8238c 100644 --- a/drivers/dma/dma-axi-dmac.c +++ b/drivers/dma/dma-axi-dmac.c @@ -415,6 +415,7 @@ static bool axi_dmac_transfer_done(struct axi_dmac_chan *chan, list_del(&active->vdesc.node); vchan_cookie_complete(&active->vdesc); active = axi_dmac_active_desc(chan); + start_next = !!active; } } else { do { @@ -1000,6 +1001,7 @@ static int axi_dmac_probe(struct platform_device *pdev) struct axi_dmac *dmac; struct regmap *regmap; unsigned int version; + u32 irq_mask = 0; int ret; dmac = devm_kzalloc(&pdev->dev, sizeof(*dmac), GFP_KERNEL); @@ -1067,7 +1069,10 @@ static int axi_dmac_probe(struct platform_device *pdev) dma_dev->copy_align = (dmac->chan.address_align_mask + 1); - axi_dmac_write(dmac, AXI_DMAC_REG_IRQ_MASK, 0x00); + if (dmac->chan.hw_sg) + irq_mask |= AXI_DMAC_IRQ_SOT; + + axi_dmac_write(dmac, AXI_DMAC_REG_IRQ_MASK, irq_mask); if (of_dma_is_coherent(pdev->dev.of_node)) { ret = axi_dmac_read(dmac, AXI_DMAC_REG_COHERENCY_DESC); -- 2.42.0