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From: Koichiro Den <den@valinux.co.jp>
To: Vinod Koul <vkoul@kernel.org>, Frank Li <Frank.Li@kernel.org>,
	Manivannan Sadhasivam <mani@kernel.org>
Cc: Marek Vasut <marek.vasut+renesas@mailbox.org>,
	Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>,
	dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH v3 01/13] dmaengine: dw-edma: Add per-channel interrupt routing control
Date: Sun, 21 Jun 2026 02:00:28 +0900	[thread overview]
Message-ID: <20260620170040.3756043-2-den@valinux.co.jp> (raw)
In-Reply-To: <20260620170040.3756043-1-den@valinux.co.jp>

DesignWare eDMA can signal completion locally through edma_int[] and
remotely through IMWr/MSI. When channels are delegated to a remote
frontend, the local endpoint side and the remote host side must not both
service the same DONE/ABORT status.

Add channel interrupt routing state and initialize it from the
controller instance configuration. Update the v0 eDMA and HDMA native
paths so linked-list interrupt generation, HDMA non-linked-list
interrupt enables, and DONE/ABORT masking follow the selected mode. For
HDMA native non-linked-list channels, use the dedicated remote
stop/abort enables without local stop/abort enables.

Keep the existing dw-edma-pcie host-side instances in remote interrupt
routing mode so their IMWr/MSI completion model remains unchanged after
local routing becomes the zero value.

Note that the routing mode describes where a channel should report
completion. It does not, by itself, say whether this dw-edma instance
owns the interrupt status. A local instance must ignore remote-only
channels, and a remote instance must ignore local-only channels, even if
such interrupts are unexpectedly delivered. Otherwise the non-owner side
could steal the interrupt from the owner by clearing shared DONE/ABORT
status.

Suggested-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Koichiro Den <den@valinux.co.jp>
---
Changes in v3:
  - Remove DW_EDMA_CH_IRQ_DEFAULT; local routing is the zero value
    (Frank).
  - Set existing dw-edma-pcie host-side instances to remote interrupt
    routing in this patch, preserving the legacy IMWr completion model.
  - Remove an unreachable HDMA native check (Sashiko).
  - Clarify local/remote instance ownership after Frank's question.
  - Mark non-owner IRQ handling guard paths unlikely.
  - Add HDMA native interrupt routing while keeping the existing non-LL
    int config ABI.
  - Keep HDMA native linked-list local interrupt generation enabled for
    remote-routed channels while masking the local edma_int[] output.
  - Use remote-only stop/abort enables for HDMA native non-LL remote-routed
    channels.
  - Drop the peripheral_config IRQ-routing ABI; initial routing comes from
    chip setup and channel ownership handoff can override it.
  - Keep dma_slave_config from resetting channel ownership routing.

 drivers/dma/dw-edma/dw-edma-core.c    | 14 +++++++++
 drivers/dma/dw-edma/dw-edma-core.h    | 13 +++++++++
 drivers/dma/dw-edma/dw-edma-pcie.c    |  1 +
 drivers/dma/dw-edma/dw-edma-v0-core.c | 22 ++++++++++----
 drivers/dma/dw-edma/dw-hdma-v0-core.c | 41 ++++++++++++++++-----------
 include/linux/dma/edma.h              | 30 ++++++++++++++++++++
 6 files changed, 99 insertions(+), 22 deletions(-)

diff --git a/drivers/dma/dw-edma/dw-edma-core.c b/drivers/dma/dw-edma/dw-edma-core.c
index 89a4c498a17b..7a24248b84e9 100644
--- a/drivers/dma/dw-edma/dw-edma-core.c
+++ b/drivers/dma/dw-edma/dw-edma-core.c
@@ -219,6 +219,17 @@ static void dw_edma_device_caps(struct dma_chan *dchan,
 	}
 }
 
+static enum dw_edma_ch_irq_mode dw_edma_get_irq_mode(struct dw_edma_chan *chan)
+{
+	struct dw_edma_chip *chip = chan->dw->chip;
+
+	if (chip->irq_mode == DW_EDMA_CH_IRQ_REMOTE &&
+	    !(chip->flags & DW_EDMA_CHIP_LOCAL))
+		return DW_EDMA_CH_IRQ_REMOTE;
+
+	return DW_EDMA_CH_IRQ_LOCAL;
+}
+
 static int dw_edma_device_config(struct dma_chan *dchan,
 				 struct dma_slave_config *config)
 {
@@ -853,6 +864,8 @@ static int dw_edma_alloc_chan_resources(struct dma_chan *dchan)
 	if (chan->status != EDMA_ST_IDLE)
 		return -EBUSY;
 
+	chan->irq_mode = dw_edma_get_irq_mode(chan);
+
 	return 0;
 }
 
@@ -904,6 +917,7 @@ static int dw_edma_channel_setup(struct dw_edma *dw, u32 wr_alloc, u32 rd_alloc)
 		chan->configured = false;
 		chan->request = EDMA_REQ_NONE;
 		chan->status = EDMA_ST_IDLE;
+		chan->irq_mode = dw_edma_get_irq_mode(chan);
 
 		if (chan->dir == EDMA_DIR_WRITE)
 			chan->ll_max = (chip->ll_region_wr[chan->id].sz / EDMA_LL_SZ);
diff --git a/drivers/dma/dw-edma/dw-edma-core.h b/drivers/dma/dw-edma/dw-edma-core.h
index 6474cacf7195..42f2f25ef377 100644
--- a/drivers/dma/dw-edma/dw-edma-core.h
+++ b/drivers/dma/dw-edma/dw-edma-core.h
@@ -81,6 +81,8 @@ struct dw_edma_chan {
 
 	struct msi_msg			msi;
 
+	enum dw_edma_ch_irq_mode	irq_mode;
+
 	enum dw_edma_request		request;
 	enum dw_edma_status		status;
 	u8				configured;
@@ -224,4 +226,15 @@ dw_edma_core_db_offset(struct dw_edma *dw)
 	return dw->core->db_offset(dw);
 }
 
+static inline bool
+dw_edma_core_ch_ignore_irq(struct dw_edma_chan *chan)
+{
+	struct dw_edma *dw = chan->dw;
+
+	if (dw->chip->flags & DW_EDMA_CHIP_LOCAL)
+		return chan->irq_mode == DW_EDMA_CH_IRQ_REMOTE;
+	else
+		return chan->irq_mode == DW_EDMA_CH_IRQ_LOCAL;
+}
+
 #endif /* _DW_EDMA_CORE_H */
diff --git a/drivers/dma/dw-edma/dw-edma-pcie.c b/drivers/dma/dw-edma/dw-edma-pcie.c
index 791c46e8ae4c..70ea031147d1 100644
--- a/drivers/dma/dw-edma/dw-edma-pcie.c
+++ b/drivers/dma/dw-edma/dw-edma-pcie.c
@@ -419,6 +419,7 @@ static int dw_edma_pcie_probe(struct pci_dev *pdev,
 	chip->dev = dev;
 
 	chip->mf = vsec_data->mf;
+	chip->irq_mode = DW_EDMA_CH_IRQ_REMOTE;
 	chip->nr_irqs = nr_irqs;
 	chip->ops = &dw_edma_pcie_plat_ops;
 	chip->cfg_non_ll = non_ll;
diff --git a/drivers/dma/dw-edma/dw-edma-v0-core.c b/drivers/dma/dw-edma/dw-edma-v0-core.c
index cfdd6463252e..1781ba4f022e 100644
--- a/drivers/dma/dw-edma/dw-edma-v0-core.c
+++ b/drivers/dma/dw-edma/dw-edma-v0-core.c
@@ -256,9 +256,11 @@ dw_edma_v0_core_handle_int(struct dw_edma_irq *dw_irq, enum dw_edma_dir dir,
 	for_each_set_bit(pos, &val, total) {
 		chan = &dw->chan[pos + off];
 
+		if (unlikely(dw_edma_core_ch_ignore_irq(chan)))
+			continue;
+
 		dw_edma_v0_core_clear_done_int(chan);
 		done(chan);
-
 		ret = IRQ_HANDLED;
 	}
 
@@ -267,9 +269,11 @@ dw_edma_v0_core_handle_int(struct dw_edma_irq *dw_irq, enum dw_edma_dir dir,
 	for_each_set_bit(pos, &val, total) {
 		chan = &dw->chan[pos + off];
 
+		if (unlikely(dw_edma_core_ch_ignore_irq(chan)))
+			continue;
+
 		dw_edma_v0_core_clear_abort_int(chan);
 		abort(chan);
-
 		ret = IRQ_HANDLED;
 	}
 
@@ -331,7 +335,8 @@ static void dw_edma_v0_core_write_chunk(struct dw_edma_chunk *chunk)
 		j--;
 		if (!j) {
 			control |= DW_EDMA_V0_LIE;
-			if (!(chan->dw->chip->flags & DW_EDMA_CHIP_LOCAL))
+			if (!(chan->dw->chip->flags & DW_EDMA_CHIP_LOCAL) &&
+			    chan->irq_mode != DW_EDMA_CH_IRQ_LOCAL)
 				control |= DW_EDMA_V0_RIE;
 		}
 
@@ -408,12 +413,17 @@ static void dw_edma_v0_core_start(struct dw_edma_chunk *chunk, bool first)
 				break;
 			}
 		}
-		/* Interrupt unmask - done, abort */
+		/* Interrupt mask/unmask - done, abort */
 		raw_spin_lock_irqsave(&dw->lock, flags);
 
 		tmp = GET_RW_32(dw, chan->dir, int_mask);
-		tmp &= ~FIELD_PREP(EDMA_V0_DONE_INT_MASK, BIT(chan->id));
-		tmp &= ~FIELD_PREP(EDMA_V0_ABORT_INT_MASK, BIT(chan->id));
+		if (chan->irq_mode == DW_EDMA_CH_IRQ_REMOTE) {
+			tmp |= FIELD_PREP(EDMA_V0_DONE_INT_MASK, BIT(chan->id));
+			tmp |= FIELD_PREP(EDMA_V0_ABORT_INT_MASK, BIT(chan->id));
+		} else {
+			tmp &= ~FIELD_PREP(EDMA_V0_DONE_INT_MASK, BIT(chan->id));
+			tmp &= ~FIELD_PREP(EDMA_V0_ABORT_INT_MASK, BIT(chan->id));
+		}
 		SET_RW_32(dw, chan->dir, int_mask, tmp);
 		/* Linked list error */
 		tmp = GET_RW_32(dw, chan->dir, linked_list_err_en);
diff --git a/drivers/dma/dw-edma/dw-hdma-v0-core.c b/drivers/dma/dw-edma/dw-hdma-v0-core.c
index 2beec876b184..7ba6bdbffc17 100644
--- a/drivers/dma/dw-edma/dw-hdma-v0-core.c
+++ b/drivers/dma/dw-edma/dw-hdma-v0-core.c
@@ -49,6 +49,26 @@ __dw_ch_regs(struct dw_edma *dw, enum dw_edma_dir dir, u16 ch)
 		writel(value, &(__dw_ch_regs(dw, EDMA_DIR_READ, ch)->name));	\
 	} while (0)
 
+static u32 dw_hdma_v0_core_int_setup(struct dw_edma_chan *chan, u32 val)
+{
+	val &= ~(HDMA_V0_LOCAL_ABORT_INT_EN | HDMA_V0_REMOTE_ABORT_INT_EN |
+		 HDMA_V0_LOCAL_STOP_INT_EN | HDMA_V0_REMOTE_STOP_INT_EN |
+		 HDMA_V0_ABORT_INT_MASK | HDMA_V0_STOP_INT_MASK);
+
+	if (chan->irq_mode == DW_EDMA_CH_IRQ_REMOTE && chan->non_ll)
+		return val | HDMA_V0_REMOTE_ABORT_INT_EN |
+		       HDMA_V0_REMOTE_STOP_INT_EN;
+
+	if (chan->irq_mode == DW_EDMA_CH_IRQ_REMOTE)
+		return val | HDMA_V0_LOCAL_ABORT_INT_EN |
+		       HDMA_V0_REMOTE_ABORT_INT_EN |
+		       HDMA_V0_LOCAL_STOP_INT_EN |
+		       HDMA_V0_REMOTE_STOP_INT_EN | HDMA_V0_ABORT_INT_MASK |
+		       HDMA_V0_STOP_INT_MASK;
+
+	return val | HDMA_V0_LOCAL_ABORT_INT_EN | HDMA_V0_LOCAL_STOP_INT_EN;
+}
+
 /* HDMA management callbacks */
 static void dw_hdma_v0_core_off(struct dw_edma *dw)
 {
@@ -132,6 +152,8 @@ dw_hdma_v0_core_handle_int(struct dw_edma_irq *dw_irq, enum dw_edma_dir dir,
 
 	for_each_set_bit(pos, &mask, total) {
 		chan = &dw->chan[pos + off];
+		if (unlikely(dw_edma_core_ch_ignore_irq(chan)))
+			continue;
 
 		val = dw_hdma_v0_core_status_int(chan);
 		if (FIELD_GET(HDMA_V0_STOP_INT_MASK, val)) {
@@ -238,11 +260,7 @@ static void dw_hdma_v0_core_ll_start(struct dw_edma_chunk *chunk, bool first)
 		SET_CH_32(dw, chan->dir, chan->id, ch_en, BIT(0));
 		/* Interrupt unmask - stop, abort */
 		tmp = GET_CH_32(dw, chan->dir, chan->id, int_setup);
-		tmp &= ~(HDMA_V0_STOP_INT_MASK | HDMA_V0_ABORT_INT_MASK);
-		/* Interrupt enable - stop, abort */
-		tmp |= HDMA_V0_LOCAL_STOP_INT_EN | HDMA_V0_LOCAL_ABORT_INT_EN;
-		if (!(dw->chip->flags & DW_EDMA_CHIP_LOCAL))
-			tmp |= HDMA_V0_REMOTE_STOP_INT_EN | HDMA_V0_REMOTE_ABORT_INT_EN;
+		tmp = dw_hdma_v0_core_int_setup(chan, tmp);
 		SET_CH_32(dw, chan->dir, chan->id, int_setup, tmp);
 		/* Channel control */
 		SET_CH_32(dw, chan->dir, chan->id, control1, HDMA_V0_LINKLIST_EN);
@@ -293,17 +311,8 @@ static void dw_hdma_v0_core_non_ll_start(struct dw_edma_chunk *chunk)
 	SET_CH_32(dw, chan->dir, chan->id, transfer_size, child->sz);
 
 	/* Interrupt setup */
-	val = GET_CH_32(dw, chan->dir, chan->id, int_setup) |
-			HDMA_V0_STOP_INT_MASK |
-			HDMA_V0_ABORT_INT_MASK |
-			HDMA_V0_LOCAL_STOP_INT_EN |
-			HDMA_V0_LOCAL_ABORT_INT_EN;
-
-	if (!(dw->chip->flags & DW_EDMA_CHIP_LOCAL)) {
-		val |= HDMA_V0_REMOTE_STOP_INT_EN |
-		       HDMA_V0_REMOTE_ABORT_INT_EN;
-	}
-
+	val = GET_CH_32(dw, chan->dir, chan->id, int_setup);
+	val = dw_hdma_v0_core_int_setup(chan, val);
 	SET_CH_32(dw, chan->dir, chan->id, int_setup, val);
 
 	/* Channel control setup */
diff --git a/include/linux/dma/edma.h b/include/linux/dma/edma.h
index 1fafd5b0e315..c0906221a7c7 100644
--- a/include/linux/dma/edma.h
+++ b/include/linux/dma/edma.h
@@ -60,6 +60,34 @@ enum dw_edma_chip_flags {
 	DW_EDMA_CHIP_LOCAL	= BIT(0),
 };
 
+/**
+ * enum dw_edma_ch_irq_mode - per-channel interrupt routing control
+ * @DW_EDMA_CH_IRQ_LOCAL:     local interrupt only (edma_int[])
+ * @DW_EDMA_CH_IRQ_REMOTE:    remote interrupt only (IMWr/MSI), without
+ *                            delivering local edma_int[].
+ *
+ * DesignWare EP eDMA can signal interrupts locally through the edma_int[]
+ * bus, and remotely using posted memory writes (IMWr) that may be
+ * interpreted as MSI/MSI-X by the RC.
+ *
+ * For the v0 eDMA linked-list programming path, DMA_*_INT_MASK gates the local
+ * edma_int[] assertion, while there is no dedicated per-channel mask for IMWr
+ * generation. To request a remote-only interrupt, Synopsys recommends setting
+ * both LIE and RIE, and masking the local interrupt in DMA_*_INT_MASK. See the
+ * DesignWare endpoint databook 6.30a, Linked List Mode interrupt handling
+ * ("Software Programming of an Endpoint's LIE and RIE Bits for Linked List
+ * Transfers", Attention).
+ *
+ * HDMA linked-list watermark interrupts have the same LWIE/RWIE guidance. HDMA
+ * non-linked-list mode has dedicated local and remote stop/abort interrupt
+ * enables, and the remote CPU programming examples use remote enables without
+ * local enables.
+ */
+enum dw_edma_ch_irq_mode {
+	DW_EDMA_CH_IRQ_LOCAL	= 0,
+	DW_EDMA_CH_IRQ_REMOTE,
+};
+
 /**
  * struct dw_edma_chip - representation of DesignWare eDMA controller hardware
  * @dev:		 struct device of the eDMA controller
@@ -76,6 +104,7 @@ enum dw_edma_chip_flags {
  * @db_irq:		 Virtual IRQ dedicated to interrupt emulation
  * @db_offset:		 Offset from DMA register base
  * @mf:			 DMA register map format
+ * @irq_mode:		 default per-channel interrupt routing
  * @dw:			 struct dw_edma that is filled by dw_edma_probe()
  */
 struct dw_edma_chip {
@@ -101,6 +130,7 @@ struct dw_edma_chip {
 	resource_size_t		db_offset;
 
 	enum dw_edma_map_format	mf;
+	enum dw_edma_ch_irq_mode	irq_mode;
 
 	struct dw_edma		*dw;
 	bool			cfg_non_ll;
-- 
2.51.0


  reply	other threads:[~2026-06-20 17:00 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-06-20 17:00 [PATCH v3 00/13] dmaengine: dw-edma: Prepare for PCI EP DMA (part 1/3) Koichiro Den
2026-06-20 17:00 ` Koichiro Den [this message]
2026-06-22 15:34   ` [PATCH v3 01/13] dmaengine: dw-edma: Add per-channel interrupt routing control Frank Li
2026-06-23  4:03     ` Koichiro Den
2026-06-20 17:00 ` [PATCH v3 02/13] dmaengine: dw-edma: Add core quiesce operations Koichiro Den
2026-06-22 15:45   ` Frank Li
2026-06-20 17:00 ` [PATCH v3 03/13] dmaengine: dw-edma: Add delegated channel request helpers Koichiro Den
2026-06-22 16:06   ` Frank Li
2026-06-23  2:57     ` Koichiro Den
2026-06-20 17:00 ` [PATCH v3 04/13] dmaengine: dw-edma: Initialize IRQ data before requesting IRQs Koichiro Den
2026-06-20 17:00 ` [PATCH v3 05/13] dmaengine: dw-edma: Add partial channel ownership mode Koichiro Den
2026-06-22 15:59   ` Frank Li
2026-06-23  3:04     ` Koichiro Den
2026-06-20 17:00 ` [PATCH v3 06/13] dmaengine: dw-edma-pcie: Track non-LL mode in DMA data Koichiro Den
2026-06-20 17:00 ` [PATCH v3 07/13] dmaengine: dw-edma-pcie: Add capability match data Koichiro Den
2026-06-20 17:00 ` [PATCH v3 08/13] dmaengine: dw-edma-pcie: Rename vsec_data to dma_data Koichiro Den
2026-06-20 17:00 ` [PATCH v3 09/13] dmaengine: dw-edma-pcie: Add platform ops to match data Koichiro Den
2026-06-20 17:00 ` [PATCH v3 10/13] dmaengine: dw-edma-pcie: Add register offset match flag Koichiro Den
2026-06-20 17:00 ` [PATCH v3 11/13] dmaengine: dw-edma-pcie: Factor out descriptor block address lookup Koichiro Den
2026-06-20 17:00 ` [PATCH v3 12/13] dmaengine: dw-edma-pcie: Handle optional data blocks Koichiro Den
2026-06-20 17:00 ` [PATCH v3 13/13] dmaengine: dw-edma-pcie: Add chip flags to match data Koichiro Den

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