linux-kernel - [PATCH 1/7] dmaengine: sh: rz-dmac: Add enable status bit

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20260126103155.2644586-2-claudiu.beznea.uj@bp.renesas.com>
Date: Mon, 26 Jan 2026 12:31:49 +0200
From: Claudiu <claudiu.beznea@...on.dev>
To: vkoul@...nel.org,
	biju.das.jz@...renesas.com,
	prabhakar.mahadev-lad.rj@...renesas.com,
	lgirdwood@...il.com,
	broonie@...nel.org,
	perex@...ex.cz,
	tiwai@...e.com,
	p.zabel@...gutronix.de,
	geert+renesas@...der.be,
	fabrizio.castro.jz@...esas.com
Cc: claudiu.beznea@...on.dev,
	dmaengine@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	linux-sound@...r.kernel.org,
	linux-renesas-soc@...r.kernel.org,
	Claudiu Beznea <claudiu.beznea.uj@...renesas.com>
Subject: [PATCH 1/7] dmaengine: sh: rz-dmac: Add enable status bit

From: Claudiu Beznea <claudiu.beznea.uj@...renesas.com>

Add a status bitmask to struct rz_dmac_chan. This is currently stores only
the enable status of the DMA channel and it is a preparatory commit for
adding cyclic DMA support.

Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@...renesas.com>
---
 drivers/dma/sh/rz-dmac.c | 24 +++++++++++++++++++++---
 1 file changed, 21 insertions(+), 3 deletions(-)

diff --git a/drivers/dma/sh/rz-dmac.c b/drivers/dma/sh/rz-dmac.c
index 35124043ae02..95ed357f2b74 100644
--- a/drivers/dma/sh/rz-dmac.c
+++ b/drivers/dma/sh/rz-dmac.c
@@ -62,6 +62,14 @@ struct rz_dmac_desc {
 
 #define to_rz_dmac_desc(d)	container_of(d, struct rz_dmac_desc, vd)
 
+/**
+ * enum rz_dmac_chan_status: RZ DMAC channel status
+ * @RZ_DMAC_CHAN_STATUS_ENABLED: Channel is enabled
+ */
+enum rz_dmac_chan_status {
+	RZ_DMAC_CHAN_STATUS_ENABLED,
+};
+
 struct rz_dmac_chan {
 	struct virt_dma_chan vc;
 	void __iomem *ch_base;
@@ -73,6 +81,8 @@ struct rz_dmac_chan {
 	dma_addr_t src_per_address;
 	dma_addr_t dst_per_address;
 
+	unsigned long status;
+
 	u32 chcfg;
 	u32 chctrl;
 	int mid_rid;
@@ -302,6 +312,8 @@ static void rz_dmac_enable_hw(struct rz_dmac_chan *channel)
 		rz_dmac_ch_writel(channel, channel->chcfg, CHCFG, 1);
 		rz_dmac_ch_writel(channel, CHCTRL_SWRST, CHCTRL, 1);
 		rz_dmac_ch_writel(channel, chctrl, CHCTRL, 1);
+
+		channel->status |= BIT(RZ_DMAC_CHAN_STATUS_ENABLED);
 	}
 }
 
@@ -313,6 +325,8 @@ static void rz_dmac_disable_hw(struct rz_dmac_chan *channel)
 	dev_dbg(dmac->dev, "%s channel %d\n", __func__, channel->index);
 
 	rz_dmac_ch_writel(channel, CHCTRL_DEFAULT, CHCTRL, 1);
+
+	channel->status &= ~BIT(RZ_DMAC_CHAN_STATUS_ENABLED);
 }
 
 static void rz_dmac_set_dmars_register(struct rz_dmac *dmac, int nr, u32 dmars)
@@ -578,6 +592,9 @@ static int rz_dmac_terminate_all(struct dma_chan *chan)
 	list_splice_tail_init(&channel->ld_active, &channel->ld_free);
 	list_splice_tail_init(&channel->ld_queue, &channel->ld_free);
 	vchan_get_all_descriptors(&channel->vc, &head);
+
+	channel->status = 0;
+
 	spin_unlock_irqrestore(&channel->vc.lock, flags);
 	vchan_dma_desc_free_list(&channel->vc, &head);
 
@@ -841,8 +858,7 @@ static int rz_dmac_device_pause(struct dma_chan *chan)
 
 	guard(spinlock_irqsave)(&channel->vc.lock);
 
-	val = rz_dmac_ch_readl(channel, CHSTAT, 1);
-	if (!(val & CHSTAT_EN))
+	if (!(channel->status & BIT(RZ_DMAC_CHAN_STATUS_ENABLED)))
 		return 0;
 
 	rz_dmac_ch_writel(channel, CHCTRL_SETSUS, CHCTRL, 1);
@@ -882,8 +898,10 @@ static void rz_dmac_irq_handle_channel(struct rz_dmac_chan *channel)
 		dev_err(dmac->dev, "DMAC err CHSTAT_%d = %08X\n",
 			channel->index, chstat);
 
-		scoped_guard(spinlock_irqsave, &channel->vc.lock)
+		scoped_guard(spinlock_irqsave, &channel->vc.lock) {
 			rz_dmac_ch_writel(channel, CHCTRL_DEFAULT, CHCTRL, 1);
+			channel->status &= ~BIT(RZ_DMAC_CHAN_STATUS_ENABLED);
+		}
 		return;
 	}
 
-- 
2.43.0