dmaengine: dw-edma: Enable HDMA 64R/W Channels

Thank you for your contribution! Sashiko AI review found 3 potential issue(s) to consider:

New issues:
- [High] The DesignWare PCIe controller integration rejects eDMA initialization for HDMA platforms with more than 8 channels because dw_pcie_edma_find_channels and dw_pcie_edma_irq_vector unconditionally enforce the old 8-channel limit.

Pre-existing issues:
- [High] The arguments dir and ch are swapped when calling GET_CH_32 in dw_hdma_v0_core_ch_status, causing it to read the wrong hardware registers.
- [High] The driver requests shared IRQs before the interrupt context data is fully initialized, exposing a NULL pointer dereference window if an interrupt fires early. --

commit cc43ddee72586cbf9f93d80ae20f2b0a9e539a31
Author: Devendra K Verma <[email protected]>

dmaengine: dw-edma: Enable HDMA 64R/W Channels

This commit updates the DesignWare eDMA driver to support up to 64 read and write channels for HDMA. It introduces HDMA-specific macros, adjusts channel counts in device structures, and switches bitmasks to 64-bit to accommodate the higher channel counts.

Quoted 4 lines

drivers/dma/dw-edma/dw-edma-core.c +0 -0

index c2feb3adc79fa..adf1b3939f96c 100644

[ ... ]

Quoted 29 lines

drivers/dma/dw-edma/dw-edma-core.c +9 -2

@@ -1079,6 +1079,8 @@ int dw_edma_probe(struct dw_edma_chip *chip)
  	struct dw_edma *dw;
  	u32 wr_alloc = 0;
  	u32 rd_alloc = 0;
+	u16 max_wr_cnt;
+	u16 max_rd_cnt;
  	int i, err;
 
  	if (!chip)

@@ -1094,20 +1096,25 @@ int dw_edma_probe(struct dw_edma_chip *chip)
 
  	dw->chip = chip;
 
-	if (dw->chip->mf == EDMA_MF_HDMA_NATIVE)
+	if (dw->chip->mf == EDMA_MF_HDMA_NATIVE) {
  		dw_hdma_v0_core_register(dw);
-	else
+		max_wr_cnt = HDMA_MAX_WR_CH;
+		max_rd_cnt = HDMA_MAX_RD_CH;
+	} else {
  		dw_edma_v0_core_register(dw);
+		max_wr_cnt = EDMA_MAX_WR_CH;
+		max_rd_cnt = EDMA_MAX_RD_CH;
+	}
 
  	raw_spin_lock_init(&dw->lock);
 
  	dw->wr_ch_cnt = min_t(u16, chip->ll_wr_cnt,
  			      dw_edma_core_ch_count(dw, EDMA_DIR_WRITE));

drivers/dma/dw-edma/dw-edma-core.c int dw_edma_probe(struct dw_edma_chip *chip) · line 1120

Quoted 10 lines

drivers/dma/dw-edma/dw-edma-core.c +2 -2

-	dw->wr_ch_cnt = min_t(u16, dw->wr_ch_cnt, EDMA_MAX_WR_CH);
+	dw->wr_ch_cnt = min_t(u16, dw->wr_ch_cnt, max_wr_cnt);
 
  	dw->rd_ch_cnt = min_t(u16, chip->ll_rd_cnt,
  			      dw_edma_core_ch_count(dw, EDMA_DIR_READ));
-	dw->rd_ch_cnt = min_t(u16, dw->rd_ch_cnt, EDMA_MAX_RD_CH);
+	dw->rd_ch_cnt = min_t(u16, dw->rd_ch_cnt, max_rd_cnt);
 
  	if (!dw->wr_ch_cnt && !dw->rd_ch_cnt)
  		return -EINVAL;

[Severity: High]
This is a pre-existing issue, but does the current probe sequence expose a window for a NULL pointer dereference if an early interrupt fires?

In dw_edma_probe(), we call dw_edma_irq_request() which registers a shared IRQ handler:

err = request_irq(irq, dw_edma_interrupt_common,
IRQF_SHARED, dw->name, &dw->irq[0]);

However, the interrupt context data (irq->dw) isn't populated until the later call to dw_edma_channel_setup():

     irq->dw = dw;

If another device sharing the same IRQ line triggers an interrupt before dw_edma_channel_setup() completes, could the handler dereference a NULL dw_irq->dw pointer?

[ ... ]

Quoted 4 lines

drivers/dma/dw-edma/dw-hdma-v0-core.c +0 -0

index 632abb8b481cf..61064de293b85 100644

[ ... ]

Quoted 15 lines

drivers/dma/dw-edma/dw-hdma-v0-core.c +3 -2

@@ -118,19 +129,20 @@ dw_hdma_v0_core_handle_int(struct dw_edma_irq *dw_irq, enum dw_edma_dir dir,
  	unsigned long total, pos, val;
  	irqreturn_t ret = IRQ_NONE;
  	struct dw_edma_chan *chan;
-	unsigned long off, mask;
+	DECLARE_BITMAP(mask, 64);
+	unsigned long off;
 
  	if (dir == EDMA_DIR_WRITE) {
  		total = dw->wr_ch_cnt;
  		off = 0;
-		mask = dw_irq->wr_mask;
+		bitmap_from_u64(mask, dw_irq->wr_mask);
  	} else {
  		total = dw->rd_ch_cnt;

drivers/dma/dw-edma/dw-hdma-v0-core.c dw_hdma_v0_core_handle_int(struct dw_edma_irq *dw_irq, enum dw_edma_dir dir, · line 148

Quoted 10 lines

drivers/dma/dw-edma/dw-hdma-v0-core.c +2 -2

  		off = dw->wr_ch_cnt;
-		mask = dw_irq->rd_mask;
+		bitmap_from_u64(mask, dw_irq->rd_mask);
  	}
 
-	for_each_set_bit(pos, &mask, total) {
+	for_each_set_bit(pos, mask, total) {
  		chan = &dw->chan[pos + off];
 
  		val = dw_hdma_v0_core_status_int(chan);

[Severity: High]
This is a pre-existing issue, but is it possible that dw_hdma_v0_core_ch_status() reads from the wrong hardware register by swapping its arguments?

When checking the status, the GET_CH_32 macro expects the direction first, then the channel:

     GET_CH_32(dw, dir, ch, name)

However, dw_hdma_v0_core_ch_status() passes chan->id before chan->dir:

tmp = FIELD_GET(HDMA_V0_CH_STATUS_MASK,
GET_CH_32(dw, chan->id, chan->dir, ch_stat));

Could this lead to incorrect channel status checks?

[ ... ]

include/linux/dma/edma.h line 21

Quoted 13 lines

include/linux/dma/edma.h +2 -0

index 1fafd5b0e3153..da7a5cc93ad43 100644
@@ -14,6 +14,8 @@
 
  #define EDMA_MAX_WR_CH                                  8
  #define EDMA_MAX_RD_CH                                  8
+#define HDMA_MAX_WR_CH                                  64
+#define HDMA_MAX_RD_CH                                  64
 
  struct dw_edma;
 

[Severity: High]
With the expansion to 64 channels, will the DesignWare PCIe controller integration reject valid HDMA configurations?

In dw_pcie_edma_find_channels(), the code unconditionally enforces the old EDMA_MAX_WR_CH (8) limits:

     if (!pci->edma.ll_wr_cnt || pci->edma.ll_wr_cnt > EDMA_MAX_WR_CH ||
         !pci->edma.ll_rd_cnt || pci->edma.ll_rd_cnt > EDMA_MAX_RD_CH)
         return -EINVAL;

Similarly, dw_pcie_edma_irq_vector() enforces a maximum of 16 vectors:

     if (nr >= EDMA_MAX_WR_CH + EDMA_MAX_RD_CH)
         return -EINVAL;

Do these bounding checks in the PCIe controller driver also need to be updated to handle the new HDMA_MAX_WR_CH and HDMA_MAX_RD_CH limits, to prevent the device probe from completely failing?

Hi Frank, Vinod

Do you have any suggestion about handling of the repeated comments from AI?
On every version of this patch the similar issues have been raised and I am replying with the same answers as many version-times. Please suggest so that multiple replies to the same queries by AI bot can be managed.

regards,
Devendra

Quoted 71 lines · On 26-Jun-26 19:16, [email protected] wrote:

Thank you for your contribution! Sashiko AI review found 3 potential issue(s) to consider:

New issues:
- [High] The DesignWare PCIe controller integration rejects eDMA initialization for HDMA platforms with more than 8 channels because dw_pcie_edma_find_channels and dw_pcie_edma_irq_vector unconditionally enforce the old 8-channel limit.

Pre-existing issues:
- [High] The arguments dir and ch are swapped when calling GET_CH_32 in dw_hdma_v0_core_ch_status, causing it to read the wrong hardware registers.
- [High] The driver requests shared IRQs before the interrupt context data is fully initialized, exposing a NULL pointer dereference window if an interrupt fires early. --

commit cc43ddee72586cbf9f93d80ae20f2b0a9e539a31
Author: Devendra K Verma <[email protected]>

dmaengine: dw-edma: Enable HDMA 64R/W Channels

This commit updates the DesignWare eDMA driver to support up to 64 read and write channels for HDMA. It introduces HDMA-specific macros, adjusts channel counts in device structures, and switches bitmasks to 64-bit to accommodate the higher channel counts.

Quoted 4 lines

drivers/dma/dw-edma/dw-edma-core.c +0 -0

index c2feb3adc79fa..adf1b3939f96c 100644

[ ... ]

Quoted 22 lines

drivers/dma/dw-edma/dw-edma-core.c +9 -2

@@ -1079,6 +1079,8 @@ int dw_edma_probe(struct dw_edma_chip *chip)
  	struct dw_edma *dw;
  	u32 wr_alloc = 0;
  	u32 rd_alloc = 0;
+	u16 max_wr_cnt;
+	u16 max_rd_cnt;
  	int i, err;
  	if (!chip)

@@ -1094,20 +1096,25 @@ int dw_edma_probe(struct dw_edma_chip *chip)
  	dw->chip = chip;
-	if (dw->chip->mf == EDMA_MF_HDMA_NATIVE)
+	if (dw->chip->mf == EDMA_MF_HDMA_NATIVE) {
  		dw_hdma_v0_core_register(dw);
-	else
+		max_wr_cnt = HDMA_MAX_WR_CH;
+		max_rd_cnt = HDMA_MAX_RD_CH;
+	} else {
  		dw_edma_v0_core_register(dw);
+		max_wr_cnt = EDMA_MAX_WR_CH;
+		max_rd_cnt = EDMA_MAX_RD_CH;
+	}
  	raw_spin_lock_init(&dw->lock);

drivers/dma/dw-edma/dw-edma-core.c int dw_edma_probe(struct dw_edma_chip *chip) · line 1114

Quoted 10 lines

drivers/dma/dw-edma/dw-edma-core.c +2 -2

  	dw->wr_ch_cnt = min_t(u16, chip->ll_wr_cnt,
  			      dw_edma_core_ch_count(dw, EDMA_DIR_WRITE));
-	dw->wr_ch_cnt = min_t(u16, dw->wr_ch_cnt, EDMA_MAX_WR_CH);
+	dw->wr_ch_cnt = min_t(u16, dw->wr_ch_cnt, max_wr_cnt);
  	dw->rd_ch_cnt = min_t(u16, chip->ll_rd_cnt,
  			      dw_edma_core_ch_count(dw, EDMA_DIR_READ));
-	dw->rd_ch_cnt = min_t(u16, dw->rd_ch_cnt, EDMA_MAX_RD_CH);
+	dw->rd_ch_cnt = min_t(u16, dw->rd_ch_cnt, max_rd_cnt);
  	if (!dw->wr_ch_cnt && !dw->rd_ch_cnt)
  		return -EINVAL;

[Severity: High]
This is a pre-existing issue, but does the current probe sequence expose a window for a NULL pointer dereference if an early interrupt fires?

In dw_edma_probe(), we call dw_edma_irq_request() which registers a shared IRQ handler:

err = request_irq(irq, dw_edma_interrupt_common,
IRQF_SHARED, dw->name, &dw->irq[0]);

However, the interrupt context data (irq->dw) isn't populated until the later call to dw_edma_channel_setup():

Quoted 7 lines

     irq->dw = dw;

If another device sharing the same IRQ line triggers an interrupt before dw_edma_channel_setup() completes, could the handler dereference a NULL dw_irq->dw pointer?

[ ... ]

As this is pre-existing issue, it shall be taken in a separate patch series.

Quoted 38 lines

Quoted 4 lines

drivers/dma/dw-edma/dw-hdma-v0-core.c +0 -0

index 632abb8b481cf..61064de293b85 100644

[ ... ]

Quoted 12 lines

drivers/dma/dw-edma/dw-hdma-v0-core.c +3 -2

@@ -118,19 +129,20 @@ dw_hdma_v0_core_handle_int(struct dw_edma_irq *dw_irq, enum dw_edma_dir dir,
  	unsigned long total, pos, val;
  	irqreturn_t ret = IRQ_NONE;
  	struct dw_edma_chan *chan;
-	unsigned long off, mask;
+	DECLARE_BITMAP(mask, 64);
+	unsigned long off;
  	if (dir == EDMA_DIR_WRITE) {
  		total = dw->wr_ch_cnt;
  		off = 0;
-		mask = dw_irq->wr_mask;
+		bitmap_from_u64(mask, dw_irq->wr_mask);

drivers/dma/dw-edma/dw-hdma-v0-core.c dw_hdma_v0_core_handle_int(struct dw_edma_irq *dw_irq, enum dw_edma_dir dir, · line 145

Quoted 10 lines

drivers/dma/dw-edma/dw-hdma-v0-core.c +2 -2

  	} else {
  		total = dw->rd_ch_cnt;
  		off = dw->wr_ch_cnt;
-		mask = dw_irq->rd_mask;
+		bitmap_from_u64(mask, dw_irq->rd_mask);
  	}
-	for_each_set_bit(pos, &mask, total) {
+	for_each_set_bit(pos, mask, total) {
  		chan = &dw->chan[pos + off];
  		val = dw_hdma_v0_core_status_int(chan);

[Severity: High]
This is a pre-existing issue, but is it possible that dw_hdma_v0_core_ch_status() reads from the wrong hardware register by swapping its arguments?

When checking the status, the GET_CH_32 macro expects the direction first, then the channel:

     GET_CH_32(dw, dir, ch, name)

Quoted 8 lines

However, dw_hdma_v0_core_ch_status() passes chan->id before chan->dir:

tmp = FIELD_GET(HDMA_V0_CH_STATUS_MASK,
GET_CH_32(dw, chan->id, chan->dir, ch_stat));

Could this lead to incorrect channel status checks?

[ ... ]

This issue shall be taken in a separate patch series.

Quoted 15 lines

include/linux/dma/edma.h line 18

Quoted 10 lines

include/linux/dma/edma.h +2 -0

index 1fafd5b0e3153..da7a5cc93ad43 100644
@@ -14,6 +14,8 @@
  #define EDMA_MAX_WR_CH                                  8
  #define EDMA_MAX_RD_CH                                  8
+#define HDMA_MAX_WR_CH                                  64
+#define HDMA_MAX_RD_CH                                  64
  struct dw_edma;

[Severity: High]
With the expansion to 64 channels, will the DesignWare PCIe controller integration reject valid HDMA configurations?

Quoted 7 lines

In dw_pcie_edma_find_channels(), the code unconditionally enforces the old EDMA_MAX_WR_CH (8) limits:

     if (!pci->edma.ll_wr_cnt || pci->edma.ll_wr_cnt > EDMA_MAX_WR_CH ||
         !pci->edma.ll_rd_cnt || pci->edma.ll_rd_cnt > EDMA_MAX_RD_CH)
         return -EINVAL;

This particular function targets non-HDMA platforms which suggests that increasing the channel limit will not affect anything here. This code shall be retained as is. It is not affected by increase in limit for HDMA channels.

Quoted 9 lines

Similarly, dw_pcie_edma_irq_vector() enforces a maximum of 16 vectors:

     if (nr >= EDMA_MAX_WR_CH + EDMA_MAX_RD_CH)
         return -EINVAL;

Do these bounding checks in the PCIe controller driver also need to be updated to handle the new HDMA_MAX_WR_CH and HDMA_MAX_RD_CH limits, to prevent the device probe from completely failing?

This shall not affect the working of IP, with minimum interrupt count of 1 also IP should work. If required, it shall be taken in a separate patch series.

Quoted 8 lines · Devendra

Hi Frank, Vinod

Do you have any suggestion about handling of the repeated comments from AI?
On every version of this patch the similar issues have been raised and I am replying with the same answers as many version-times. Please suggest so that multiple replies to the same queries by AI bot can be managed.

You can omit pre-existing. Only reply once when patch close to land. I hope there are tool, which can help identified comments and pull your previous reply.

On method may help:

After I provided review-by, you can reply you already checked AI's results, so It help vnod offload his checking work.

AI is quite new for us. we are looking for efficent flow to handle it.

Quoted 10 lines · Frank Li

Quoted 8 lines · Devendra

Hi Frank, Vinod

Do you have any suggestion about handling of the repeated comments from AI?
On every version of this patch the similar issues have been raised and I am replying with the same answers as many version-times. Please suggest so that multiple replies to the same queries by AI bot can be managed.

Quoted 3 lines

You can omit pre-existing. Only reply once when patch close to land. I hope there are tool, which can help identified comments and pull your previous reply.

Right, fixing preexisting is indeed optional but since it may impact your device, we are looking forward to fixes on these from you. More important for us is not adding new issues.

Quoted 4 lines

On method may help:

After I provided review-by, you can reply you already checked AI's results, so It help vnod offload his checking work.

Thanks this helps a lot.

Quoted 1 line

AI is quite new for us. we are looking for efficent flow to handle it.

Just like any other tool, it is tool which helps us. People should also run the locally as well.

As per 'Designware Cores PCI Express Controller Databook', Section 7.1 - Overview, HDMA supports 64 Read and 64 Write channels. Current controller driver supports up to 8 read and write channels only. In order to utilize all the channels the controller driver need to have the channel related structs and variables as per the number of channels supported by IP. Following changes are made to enable 64 Read / 64 Write channel support:

o Defined HDMA specific macros to reflect the channel count.
o The count of ll_regions and dt_regions in dw_edma_chip and dw_edma_pcie_data shall be in accordance to number of read and write channels.
o In dw_edma_probe() configure the channels as per the channels of the IP used.
o Changed mask types to u64 for higher channel counts.

Signed-off-by Devendra K Verma <[email protected]>

---
Changes in v4:
o Changed 'mask' variable to a bitmap type as per the review comment.

Changes in v3:
o Reverted the FIX for AI reported GET_CH_32() issue, as per the recommendation of reviewers, need to create separate patch for it.

Changes in v2:
o Fixed the pre-existing bug related to GET_CH_32 interchanging the channel direction and id. This bug was not caused by any version of this patch.
o Fixed the issue when using for_each_set_bit() for mask of u64 type.

Changes in v1:
o On review recommendation of sashiko bot, in the function dw_hdma_v0_core_off(), the loop iterates over registers as per the number of channels enabled and not on total number of channels supported.
o Changed mask types to u64 for higher channel counts.

---
 drivers/dma/dw-edma/dw-edma-core.c    | 19 +++++++++++-----
 drivers/dma/dw-edma/dw-edma-core.h    |  4 ++--
 drivers/dma/dw-edma/dw-edma-pcie.c    |  8 +++----
 drivers/dma/dw-edma/dw-hdma-v0-core.c | 32 ++++++++++++++++++---------
 drivers/dma/dw-edma/dw-hdma-v0-regs.h |  2 +-
 include/linux/dma/edma.h              | 10 +++++----
 6 files changed, 48 insertions(+), 27 deletions(-)

drivers/dma/dw-edma/dw-edma-core.c +13 -6

index c2feb3adc79f..adf1b3939f96 100644
@@ -925,9 +925,9 @@ static int dw_edma_channel_setup(struct dw_edma *dw, u32 wr_alloc, u32 rd_alloc)
 		irq = &dw->irq[pos];
 
 		if (chan->dir == EDMA_DIR_WRITE)
-			irq->wr_mask |= BIT(chan->id);
+			irq->wr_mask |= BIT_ULL(chan->id);
 		else
-			irq->rd_mask |= BIT(chan->id);
+			irq->rd_mask |= BIT_ULL(chan->id);
 
 		irq->dw = dw;
 		memcpy(&chan->msi, &irq->msi, sizeof(chan->msi));

@@ -1079,6 +1079,8 @@ int dw_edma_probe(struct dw_edma_chip *chip)
 	struct dw_edma *dw;
 	u32 wr_alloc = 0;
 	u32 rd_alloc = 0;
+	u16 max_wr_cnt;
+	u16 max_rd_cnt;
 	int i, err;
 
 	if (!chip)

@@ -1094,20 +1096,25 @@ int dw_edma_probe(struct dw_edma_chip *chip)
 
 	dw->chip = chip;
 
-	if (dw->chip->mf == EDMA_MF_HDMA_NATIVE)
+	if (dw->chip->mf == EDMA_MF_HDMA_NATIVE) {
 		dw_hdma_v0_core_register(dw);
-	else
+		max_wr_cnt = HDMA_MAX_WR_CH;
+		max_rd_cnt = HDMA_MAX_RD_CH;
+	} else {
 		dw_edma_v0_core_register(dw);
+		max_wr_cnt = EDMA_MAX_WR_CH;
+		max_rd_cnt = EDMA_MAX_RD_CH;
+	}
 
 	raw_spin_lock_init(&dw->lock);
 
 	dw->wr_ch_cnt = min_t(u16, chip->ll_wr_cnt,
 			      dw_edma_core_ch_count(dw, EDMA_DIR_WRITE));
-	dw->wr_ch_cnt = min_t(u16, dw->wr_ch_cnt, EDMA_MAX_WR_CH);
+	dw->wr_ch_cnt = min_t(u16, dw->wr_ch_cnt, max_wr_cnt);
 
 	dw->rd_ch_cnt = min_t(u16, chip->ll_rd_cnt,
 			      dw_edma_core_ch_count(dw, EDMA_DIR_READ));
-	dw->rd_ch_cnt = min_t(u16, dw->rd_ch_cnt, EDMA_MAX_RD_CH);
+	dw->rd_ch_cnt = min_t(u16, dw->rd_ch_cnt, max_rd_cnt);
 
 	if (!dw->wr_ch_cnt && !dw->rd_ch_cnt)
 		return -EINVAL;

drivers/dma/dw-edma/dw-edma-core.h +0 -0

index 902574b1ba86..d12fefbf3952 100644

drivers/dma/dw-edma/dw-edma-core.h +0 -0

 	struct dw_edma			*dw;
 };
 

drivers/dma/dw-edma/dw-edma-pcie.c +0 -0

index 0b30ce138503..79f653da8e0f 100644

drivers/dma/dw-edma/dw-edma-pcie.c +5 -3

+	DECLARE_BITMAP(mask, 64);
+	unsigned long off;
 
 	if (dir == EDMA_DIR_WRITE) {
 		total = dw->wr_ch_cnt;
 		off = 0;
-		mask = dw_irq->wr_mask;
+		bitmap_from_u64(mask, dw_irq->wr_mask);
 	} else {
 		total = dw->rd_ch_cnt;
 		off = dw->wr_ch_cnt;
-		mask = dw_irq->rd_mask;
+		bitmap_from_u64(mask, dw_irq->rd_mask);
 	}
 
-	for_each_set_bit(pos, &mask, total) {
+	for_each_set_bit(pos, mask, total) {
 		chan = &dw->chan[pos + off];
 
 		val = dw_hdma_v0_core_status_int(chan);

drivers/dma/dw-edma/dw-hdma-v0-regs.h +1 -1

index 7759ba9b4850..48e40efceb2e 100644
@@ -11,7 +11,7 @@
 
 #include <linux/dmaengine.h>
 
-#define HDMA_V0_MAX_NR_CH			8
+#define HDMA_V0_MAX_NR_CH			64
 #define HDMA_V0_CH_EN				BIT(0)
 #define HDMA_V0_LOCAL_ABORT_INT_EN		BIT(6)
 #define HDMA_V0_REMOTE_ABORT_INT_EN		BIT(5)

include/linux/dma/edma.h +6 -5

index 1fafd5b0e315..da7a5cc93ad4 100644
@@ -14,6 +14,8 @@
 
 #define EDMA_MAX_WR_CH                                  8
 #define EDMA_MAX_RD_CH                                  8
+#define HDMA_MAX_WR_CH                                  64
+#define HDMA_MAX_RD_CH                                  64
 
 struct dw_edma;
 

@@ -89,12 +91,12 @@ struct dw_edma_chip {
 	u16			ll_wr_cnt;
 	u16			ll_rd_cnt;
 	/* link list address */
-	struct dw_edma_region	ll_region_wr[EDMA_MAX_WR_CH];
-	struct dw_edma_region	ll_region_rd[EDMA_MAX_RD_CH];
+	struct dw_edma_region	ll_region_wr[HDMA_MAX_WR_CH];
+	struct dw_edma_region	ll_region_rd[HDMA_MAX_RD_CH];
 
 	/* data region */
-	struct dw_edma_region	dt_region_wr[EDMA_MAX_WR_CH];
-	struct dw_edma_region	dt_region_rd[EDMA_MAX_RD_CH];
+	struct dw_edma_region	dt_region_wr[HDMA_MAX_WR_CH];
+	struct dw_edma_region	dt_region_rd[HDMA_MAX_RD_CH];
 
 	/* interrupt emulation */
 	int			db_irq;
--

2.43.0

Quoted 110 lines · Devendra K Verma

As per 'Designware Cores PCI Express Controller Databook', Section 7.1 - Overview, HDMA supports 64 Read and 64 Write channels. Current controller driver supports up to 8 read and write channels only. In order to utilize all the channels the controller driver need to have the channel related structs and variables as per the number of channels supported by IP. Following changes are made to enable 64 Read / 64 Write channel support:

o Defined HDMA specific macros to reflect the channel count.
o The count of ll_regions and dt_regions in dw_edma_chip and dw_edma_pcie_data shall be in accordance to number of read and write channels.
o In dw_edma_probe() configure the channels as per the channels of the IP used.
o Changed mask types to u64 for higher channel counts.

Signed-off-by Devendra K Verma <[email protected]>

---
Changes in v4:
o Changed 'mask' variable to a bitmap type as per the review comment.

Changes in v3:
o Reverted the FIX for AI reported GET_CH_32() issue, as per the recommendation of reviewers, need to create separate patch for it.

Changes in v2:
o Fixed the pre-existing bug related to GET_CH_32 interchanging the channel direction and id. This bug was not caused by any version of this patch.
o Fixed the issue when using for_each_set_bit() for mask of u64 type.

Changes in v1:
o On review recommendation of sashiko bot, in the function dw_hdma_v0_core_off(), the loop iterates over registers as per the number of channels enabled and not on total number of channels supported.
o Changed mask types to u64 for higher channel counts.

---
  drivers/dma/dw-edma/dw-edma-core.c    | 19 +++++++++++-----
  drivers/dma/dw-edma/dw-edma-core.h    |  4 ++--
  drivers/dma/dw-edma/dw-edma-pcie.c    |  8 +++----
  drivers/dma/dw-edma/dw-hdma-v0-core.c | 32 ++++++++++++++++++---------
  drivers/dma/dw-edma/dw-hdma-v0-regs.h |  2 +-
  include/linux/dma/edma.h              | 10 +++++----
  6 files changed, 48 insertions(+), 27 deletions(-)

drivers/dma/dw-edma/dw-edma-core.c +13 -6

index c2feb3adc79f..adf1b3939f96 100644
@@ -925,9 +925,9 @@ static int dw_edma_channel_setup(struct dw_edma *dw, u32 wr_alloc, u32 rd_alloc)
  		irq = &dw->irq[pos];
 
  		if (chan->dir == EDMA_DIR_WRITE)
-			irq->wr_mask |= BIT(chan->id);
+			irq->wr_mask |= BIT_ULL(chan->id);
  		else
-			irq->rd_mask |= BIT(chan->id);
+			irq->rd_mask |= BIT_ULL(chan->id);
 
  		irq->dw = dw;
  		memcpy(&chan->msi, &irq->msi, sizeof(chan->msi));

@@ -1079,6 +1079,8 @@ int dw_edma_probe(struct dw_edma_chip *chip)
  	struct dw_edma *dw;
  	u32 wr_alloc = 0;
  	u32 rd_alloc = 0;
+	u16 max_wr_cnt;
+	u16 max_rd_cnt;
  	int i, err;
 
  	if (!chip)

@@ -1094,20 +1096,25 @@ int dw_edma_probe(struct dw_edma_chip *chip)
 
  	dw->chip = chip;
 
-	if (dw->chip->mf == EDMA_MF_HDMA_NATIVE)
+	if (dw->chip->mf == EDMA_MF_HDMA_NATIVE) {
  		dw_hdma_v0_core_register(dw);
-	else
+		max_wr_cnt = HDMA_MAX_WR_CH;
+		max_rd_cnt = HDMA_MAX_RD_CH;
+	} else {
  		dw_edma_v0_core_register(dw);
+		max_wr_cnt = EDMA_MAX_WR_CH;
+		max_rd_cnt = EDMA_MAX_RD_CH;
+	}
 
  	raw_spin_lock_init(&dw->lock);
 
  	dw->wr_ch_cnt = min_t(u16, chip->ll_wr_cnt,
  			      dw_edma_core_ch_count(dw, EDMA_DIR_WRITE));
-	dw->wr_ch_cnt = min_t(u16, dw->wr_ch_cnt, EDMA_MAX_WR_CH);
+	dw->wr_ch_cnt = min_t(u16, dw->wr_ch_cnt, max_wr_cnt);
 
  	dw->rd_ch_cnt = min_t(u16, chip->ll_rd_cnt,
  			      dw_edma_core_ch_count(dw, EDMA_DIR_READ));
-	dw->rd_ch_cnt = min_t(u16, dw->rd_ch_cnt, EDMA_MAX_RD_CH);
+	dw->rd_ch_cnt = min_t(u16, dw->rd_ch_cnt, max_rd_cnt);
 
  	if (!dw->wr_ch_cnt && !dw->rd_ch_cnt)
  		return -EINVAL;

drivers/dma/dw-edma/dw-edma-core.h +0 -0

index 902574b1ba86..d12fefbf3952 100644

drivers/dma/dw-edma/dw-edma-core.h struct dw_edma_chan { · line 95

Quoted 7 lines

drivers/dma/dw-edma/dw-edma-core.h +2 -2

@@ -91,8 +91,8 @@ struct dw_edma_chan {
 
  struct dw_edma_irq {
  	struct msi_msg                  msi;
-	u32				wr_mask;
-	u32				rd_mask;
+	u64				wr_mask;
+	u64				rd_mask;

Can you direct use DECLARE_BITMAP(rd_mask, 64) here?

Quoted 7 lines

drivers/dma/dw-edma/dw-edma-core.h +0 -0

  	struct dw_edma			*dw;
  };
 

drivers/dma/dw-edma/dw-edma-pcie.c +0 -0

index 0b30ce138503..79f653da8e0f 100644

...

drivers/dma/dw-edma/dw-edma-pcie.c dw_hdma_v0_core_handle_int(struct dw_edma_irq *dw_irq, enum dw_edma_dir dir, · line 121

Quoted 8 lines

  	}
  }

drivers/dma/dw-edma/dw-edma-pcie.c +0 -1

@@ -118,19 +129,20 @@ dw_hdma_v0_core_handle_int(struct dw_edma_irq *dw_irq, enum dw_edma_dir dir,
  	unsigned long total, pos, val;
  	irqreturn_t ret = IRQ_NONE;
  	struct dw_edma_chan *chan;
-	unsigned long off, mask;

after change wr_mask to BITMAP

	mask -> *mask

So needn't change this code if support more channel in future.

Frank

Quoted 66 lines

drivers/dma/dw-edma/dw-edma-pcie.c +5 -3

+	DECLARE_BITMAP(mask, 64);
+	unsigned long off;
 
  	if (dir == EDMA_DIR_WRITE) {
  		total = dw->wr_ch_cnt;
  		off = 0;
-		mask = dw_irq->wr_mask;
+		bitmap_from_u64(mask, dw_irq->wr_mask);
  	} else {
  		total = dw->rd_ch_cnt;
  		off = dw->wr_ch_cnt;
-		mask = dw_irq->rd_mask;
+		bitmap_from_u64(mask, dw_irq->rd_mask);
  	}
 
-	for_each_set_bit(pos, &mask, total) {
+	for_each_set_bit(pos, mask, total) {
  		chan = &dw->chan[pos + off];
 
  		val = dw_hdma_v0_core_status_int(chan);

drivers/dma/dw-edma/dw-hdma-v0-regs.h +1 -1

index 7759ba9b4850..48e40efceb2e 100644
@@ -11,7 +11,7 @@
 
  #include <linux/dmaengine.h>
 
-#define HDMA_V0_MAX_NR_CH			8
+#define HDMA_V0_MAX_NR_CH			64
  #define HDMA_V0_CH_EN				BIT(0)
  #define HDMA_V0_LOCAL_ABORT_INT_EN		BIT(6)
  #define HDMA_V0_REMOTE_ABORT_INT_EN		BIT(5)

include/linux/dma/edma.h +6 -5

index 1fafd5b0e315..da7a5cc93ad4 100644
@@ -14,6 +14,8 @@
 
  #define EDMA_MAX_WR_CH                                  8
  #define EDMA_MAX_RD_CH                                  8
+#define HDMA_MAX_WR_CH                                  64
+#define HDMA_MAX_RD_CH                                  64
 
  struct dw_edma;
 

@@ -89,12 +91,12 @@ struct dw_edma_chip {
  	u16			ll_wr_cnt;
  	u16			ll_rd_cnt;
  	/* link list address */
-	struct dw_edma_region	ll_region_wr[EDMA_MAX_WR_CH];
-	struct dw_edma_region	ll_region_rd[EDMA_MAX_RD_CH];
+	struct dw_edma_region	ll_region_wr[HDMA_MAX_WR_CH];
+	struct dw_edma_region	ll_region_rd[HDMA_MAX_RD_CH];
 
  	/* data region */
-	struct dw_edma_region	dt_region_wr[EDMA_MAX_WR_CH];
-	struct dw_edma_region	dt_region_rd[EDMA_MAX_RD_CH];
+	struct dw_edma_region	dt_region_wr[HDMA_MAX_WR_CH];
+	struct dw_edma_region	dt_region_rd[HDMA_MAX_RD_CH];
 
  	/* interrupt emulation */
  	int			db_irq;
--

2.43.0

Quoted 144 lines · Frank Li

Quoted 110 lines · Devendra K Verma

As per 'Designware Cores PCI Express Controller Databook', Section 7.1 - Overview, HDMA supports 64 Read and 64 Write channels. Current controller driver supports up to 8 read and write channels only. In order to utilize all the channels the controller driver need to have the channel related structs and variables as per the number of channels supported by IP. Following changes are made to enable 64 Read / 64 Write channel support:

o Defined HDMA specific macros to reflect the channel count.
o The count of ll_regions and dt_regions in dw_edma_chip and dw_edma_pcie_data shall be in accordance to number of read and write channels.
o In dw_edma_probe() configure the channels as per the channels of the IP used.
o Changed mask types to u64 for higher channel counts.

Signed-off-by Devendra K Verma <[email protected]>

---
Changes in v4:
o Changed 'mask' variable to a bitmap type as per the review comment.

Changes in v3:
o Reverted the FIX for AI reported GET_CH_32() issue, as per the recommendation of reviewers, need to create separate patch for it.

Changes in v2:
o Fixed the pre-existing bug related to GET_CH_32 interchanging the channel direction and id. This bug was not caused by any version of this patch.
o Fixed the issue when using for_each_set_bit() for mask of u64 type.

Changes in v1:
o On review recommendation of sashiko bot, in the function dw_hdma_v0_core_off(), the loop iterates over registers as per the number of channels enabled and not on total number of channels supported.
o Changed mask types to u64 for higher channel counts.

---
  drivers/dma/dw-edma/dw-edma-core.c    | 19 +++++++++++-----
  drivers/dma/dw-edma/dw-edma-core.h    |  4 ++--
  drivers/dma/dw-edma/dw-edma-pcie.c    |  8 +++----
  drivers/dma/dw-edma/dw-hdma-v0-core.c | 32 ++++++++++++++++++---------
  drivers/dma/dw-edma/dw-hdma-v0-regs.h |  2 +-
  include/linux/dma/edma.h              | 10 +++++----
  6 files changed, 48 insertions(+), 27 deletions(-)

drivers/dma/dw-edma/dw-edma-core.c +13 -6

index c2feb3adc79f..adf1b3939f96 100644
@@ -925,9 +925,9 @@ static int dw_edma_channel_setup(struct dw_edma *dw, u32 wr_alloc, u32 rd_alloc)
  		irq = &dw->irq[pos];
 
  		if (chan->dir == EDMA_DIR_WRITE)
-			irq->wr_mask |= BIT(chan->id);
+			irq->wr_mask |= BIT_ULL(chan->id);
  		else
-			irq->rd_mask |= BIT(chan->id);
+			irq->rd_mask |= BIT_ULL(chan->id);
 
  		irq->dw = dw;
  		memcpy(&chan->msi, &irq->msi, sizeof(chan->msi));

@@ -1079,6 +1079,8 @@ int dw_edma_probe(struct dw_edma_chip *chip)
  	struct dw_edma *dw;
  	u32 wr_alloc = 0;
  	u32 rd_alloc = 0;
+	u16 max_wr_cnt;
+	u16 max_rd_cnt;
  	int i, err;
 
  	if (!chip)

@@ -1094,20 +1096,25 @@ int dw_edma_probe(struct dw_edma_chip *chip)
 
  	dw->chip = chip;
 
-	if (dw->chip->mf == EDMA_MF_HDMA_NATIVE)
+	if (dw->chip->mf == EDMA_MF_HDMA_NATIVE) {
  		dw_hdma_v0_core_register(dw);
-	else
+		max_wr_cnt = HDMA_MAX_WR_CH;
+		max_rd_cnt = HDMA_MAX_RD_CH;
+	} else {
  		dw_edma_v0_core_register(dw);
+		max_wr_cnt = EDMA_MAX_WR_CH;
+		max_rd_cnt = EDMA_MAX_RD_CH;
+	}
 
  	raw_spin_lock_init(&dw->lock);
 
  	dw->wr_ch_cnt = min_t(u16, chip->ll_wr_cnt,
  			      dw_edma_core_ch_count(dw, EDMA_DIR_WRITE));
-	dw->wr_ch_cnt = min_t(u16, dw->wr_ch_cnt, EDMA_MAX_WR_CH);
+	dw->wr_ch_cnt = min_t(u16, dw->wr_ch_cnt, max_wr_cnt);
 
  	dw->rd_ch_cnt = min_t(u16, chip->ll_rd_cnt,
  			      dw_edma_core_ch_count(dw, EDMA_DIR_READ));
-	dw->rd_ch_cnt = min_t(u16, dw->rd_ch_cnt, EDMA_MAX_RD_CH);
+	dw->rd_ch_cnt = min_t(u16, dw->rd_ch_cnt, max_rd_cnt);
 
  	if (!dw->wr_ch_cnt && !dw->rd_ch_cnt)
  		return -EINVAL;

drivers/dma/dw-edma/dw-edma-core.h +0 -0

index 902574b1ba86..d12fefbf3952 100644

drivers/dma/dw-edma/dw-edma-core.h struct dw_edma_chan { · line 95

Quoted 7 lines

drivers/dma/dw-edma/dw-edma-core.h +2 -2

@@ -91,8 +91,8 @@ struct dw_edma_chan {
 
  struct dw_edma_irq {
  	struct msi_msg                  msi;
-	u32				wr_mask;
-	u32				rd_mask;
+	u64				wr_mask;
+	u64				rd_mask;

Can you direct use DECLARE_BITMAP(rd_mask, 64) here?

Quoted 7 lines

drivers/dma/dw-edma/dw-edma-core.h +0 -0

  	struct dw_edma			*dw;
  };
 

drivers/dma/dw-edma/dw-edma-pcie.c +0 -0

index 0b30ce138503..79f653da8e0f 100644

...

drivers/dma/dw-edma/dw-edma-pcie.c dw_hdma_v0_core_handle_int(struct dw_edma_irq *dw_irq, enum dw_edma_dir dir, · line 121

Quoted 8 lines

  	}
  }

drivers/dma/dw-edma/dw-edma-pcie.c +0 -1

@@ -118,19 +129,20 @@ dw_hdma_v0_core_handle_int(struct dw_edma_irq *dw_irq, enum dw_edma_dir dir,
  	unsigned long total, pos, val;
  	irqreturn_t ret = IRQ_NONE;
  	struct dw_edma_chan *chan;
-	unsigned long off, mask;

after change wr_mask to BITMAP

	mask -> *mask

So needn't change this code if support more channel in future.

Quoted 2 lines

Frank

It looks good to make this piece of code generic and support for more channel but I did not push that change as the final limitation comes from the HDMA IP which as per the documentation supports upto 64 channels only. As there is no channel increase BITMAP was not implemented for *_mask variable.

-Devendra

Quoted 66 lines

Quoted 66 lines

drivers/dma/dw-edma/dw-edma-pcie.c +5 -3

+	DECLARE_BITMAP(mask, 64);
+	unsigned long off;
 
  	if (dir == EDMA_DIR_WRITE) {
  		total = dw->wr_ch_cnt;
  		off = 0;
-		mask = dw_irq->wr_mask;
+		bitmap_from_u64(mask, dw_irq->wr_mask);
  	} else {
  		total = dw->rd_ch_cnt;
  		off = dw->wr_ch_cnt;
-		mask = dw_irq->rd_mask;
+		bitmap_from_u64(mask, dw_irq->rd_mask);
  	}
 
-	for_each_set_bit(pos, &mask, total) {
+	for_each_set_bit(pos, mask, total) {
  		chan = &dw->chan[pos + off];
 
  		val = dw_hdma_v0_core_status_int(chan);

drivers/dma/dw-edma/dw-hdma-v0-regs.h +1 -1

index 7759ba9b4850..48e40efceb2e 100644
@@ -11,7 +11,7 @@
 
  #include <linux/dmaengine.h>
 
-#define HDMA_V0_MAX_NR_CH			8
+#define HDMA_V0_MAX_NR_CH			64
  #define HDMA_V0_CH_EN				BIT(0)
  #define HDMA_V0_LOCAL_ABORT_INT_EN		BIT(6)
  #define HDMA_V0_REMOTE_ABORT_INT_EN		BIT(5)

include/linux/dma/edma.h +6 -5

index 1fafd5b0e315..da7a5cc93ad4 100644
@@ -14,6 +14,8 @@
 
  #define EDMA_MAX_WR_CH                                  8
  #define EDMA_MAX_RD_CH                                  8
+#define HDMA_MAX_WR_CH                                  64
+#define HDMA_MAX_RD_CH                                  64
 
  struct dw_edma;
 

@@ -89,12 +91,12 @@ struct dw_edma_chip {
  	u16			ll_wr_cnt;
  	u16			ll_rd_cnt;
  	/* link list address */
-	struct dw_edma_region	ll_region_wr[EDMA_MAX_WR_CH];
-	struct dw_edma_region	ll_region_rd[EDMA_MAX_RD_CH];
+	struct dw_edma_region	ll_region_wr[HDMA_MAX_WR_CH];
+	struct dw_edma_region	ll_region_rd[HDMA_MAX_RD_CH];
 
  	/* data region */
-	struct dw_edma_region	dt_region_wr[EDMA_MAX_WR_CH];
-	struct dw_edma_region	dt_region_rd[EDMA_MAX_RD_CH];
+	struct dw_edma_region	dt_region_wr[HDMA_MAX_WR_CH];
+	struct dw_edma_region	dt_region_rd[HDMA_MAX_RD_CH];
 
  	/* interrupt emulation */
  	int			db_irq;
--

2.43.0

Quoted 146 lines · Devendra

Quoted 144 lines · Frank Li

Quoted 110 lines · Devendra K Verma

As per 'Designware Cores PCI Express Controller Databook', Section 7.1 - Overview, HDMA supports 64 Read and 64 Write channels. Current controller driver supports up to 8 read and write channels only. In order to utilize all the channels the controller driver need to have the channel related structs and variables as per the number of channels supported by IP. Following changes are made to enable 64 Read / 64 Write channel support:

o Defined HDMA specific macros to reflect the channel count.
o The count of ll_regions and dt_regions in dw_edma_chip and dw_edma_pcie_data shall be in accordance to number of read and write channels.
o In dw_edma_probe() configure the channels as per the channels of the IP used.
o Changed mask types to u64 for higher channel counts.

Signed-off-by Devendra K Verma <[email protected]>

---
Changes in v4:
o Changed 'mask' variable to a bitmap type as per the review comment.

Changes in v3:
o Reverted the FIX for AI reported GET_CH_32() issue, as per the recommendation of reviewers, need to create separate patch for it.

Changes in v2:
o Fixed the pre-existing bug related to GET_CH_32 interchanging the channel direction and id. This bug was not caused by any version of this patch.
o Fixed the issue when using for_each_set_bit() for mask of u64 type.

Changes in v1:
o On review recommendation of sashiko bot, in the function dw_hdma_v0_core_off(), the loop iterates over registers as per the number of channels enabled and not on total number of channels supported.
o Changed mask types to u64 for higher channel counts.

---
   drivers/dma/dw-edma/dw-edma-core.c    | 19 +++++++++++-----
   drivers/dma/dw-edma/dw-edma-core.h    |  4 ++--
   drivers/dma/dw-edma/dw-edma-pcie.c    |  8 +++----
   drivers/dma/dw-edma/dw-hdma-v0-core.c | 32 ++++++++++++++++++---------
   drivers/dma/dw-edma/dw-hdma-v0-regs.h |  2 +-
   include/linux/dma/edma.h              | 10 +++++----
   6 files changed, 48 insertions(+), 27 deletions(-)

drivers/dma/dw-edma/dw-edma-core.c +13 -6

index c2feb3adc79f..adf1b3939f96 100644
@@ -925,9 +925,9 @@ static int dw_edma_channel_setup(struct dw_edma *dw, u32 wr_alloc, u32 rd_alloc)
   		irq = &dw->irq[pos];
 
   		if (chan->dir == EDMA_DIR_WRITE)
-			irq->wr_mask |= BIT(chan->id);
+			irq->wr_mask |= BIT_ULL(chan->id);
   		else
-			irq->rd_mask |= BIT(chan->id);
+			irq->rd_mask |= BIT_ULL(chan->id);
 
   		irq->dw = dw;
   		memcpy(&chan->msi, &irq->msi, sizeof(chan->msi));

@@ -1079,6 +1079,8 @@ int dw_edma_probe(struct dw_edma_chip *chip)
   	struct dw_edma *dw;
   	u32 wr_alloc = 0;
   	u32 rd_alloc = 0;
+	u16 max_wr_cnt;
+	u16 max_rd_cnt;
   	int i, err;
 
   	if (!chip)

@@ -1094,20 +1096,25 @@ int dw_edma_probe(struct dw_edma_chip *chip)
 
   	dw->chip = chip;
 
-	if (dw->chip->mf == EDMA_MF_HDMA_NATIVE)
+	if (dw->chip->mf == EDMA_MF_HDMA_NATIVE) {
   		dw_hdma_v0_core_register(dw);
-	else
+		max_wr_cnt = HDMA_MAX_WR_CH;
+		max_rd_cnt = HDMA_MAX_RD_CH;
+	} else {
   		dw_edma_v0_core_register(dw);
+		max_wr_cnt = EDMA_MAX_WR_CH;
+		max_rd_cnt = EDMA_MAX_RD_CH;
+	}
 
   	raw_spin_lock_init(&dw->lock);
 
   	dw->wr_ch_cnt = min_t(u16, chip->ll_wr_cnt,
   			      dw_edma_core_ch_count(dw, EDMA_DIR_WRITE));
-	dw->wr_ch_cnt = min_t(u16, dw->wr_ch_cnt, EDMA_MAX_WR_CH);
+	dw->wr_ch_cnt = min_t(u16, dw->wr_ch_cnt, max_wr_cnt);
 
   	dw->rd_ch_cnt = min_t(u16, chip->ll_rd_cnt,
   			      dw_edma_core_ch_count(dw, EDMA_DIR_READ));
-	dw->rd_ch_cnt = min_t(u16, dw->rd_ch_cnt, EDMA_MAX_RD_CH);
+	dw->rd_ch_cnt = min_t(u16, dw->rd_ch_cnt, max_rd_cnt);
 
   	if (!dw->wr_ch_cnt && !dw->rd_ch_cnt)
   		return -EINVAL;

drivers/dma/dw-edma/dw-edma-core.h +0 -0

index 902574b1ba86..d12fefbf3952 100644

drivers/dma/dw-edma/dw-edma-core.h struct dw_edma_chan { · line 95

Quoted 7 lines

drivers/dma/dw-edma/dw-edma-core.h +2 -2

@@ -91,8 +91,8 @@ struct dw_edma_chan {
 
   struct dw_edma_irq {
   	struct msi_msg                  msi;
-	u32				wr_mask;
-	u32				rd_mask;
+	u64				wr_mask;
+	u64				rd_mask;

Can you direct use DECLARE_BITMAP(rd_mask, 64) here?

Quoted 7 lines

drivers/dma/dw-edma/dw-edma-core.h +0 -0

   	struct dw_edma			*dw;
   };
 

drivers/dma/dw-edma/dw-edma-pcie.c +0 -0

index 0b30ce138503..79f653da8e0f 100644

...

drivers/dma/dw-edma/dw-edma-pcie.c dw_hdma_v0_core_handle_int(struct dw_edma_irq *dw_irq, enum dw_edma_dir dir, · line 121

Quoted 8 lines

   	}
   }

drivers/dma/dw-edma/dw-edma-pcie.c +0 -1

@@ -118,19 +129,20 @@ dw_hdma_v0_core_handle_int(struct dw_edma_irq *dw_irq, enum dw_edma_dir dir,
   	unsigned long total, pos, val;
   	irqreturn_t ret = IRQ_NONE;
   	struct dw_edma_chan *chan;
-	unsigned long off, mask;

after change wr_mask to BITMAP

	mask -> *mask

So needn't change this code if support more channel in future.

Quoted 8 lines

Quoted 2 lines

Frank

It looks good to make this piece of code generic and support for more channel but I did not push that change as the final limitation comes from the HDMA IP which as per the documentation supports upto 64 channels only. As there is no channel increase BITMAP was not implemented for *_mask variable.

DECLARE_BITMAP(rd_mask, 64) the size is the same as u64. needn't call below two bitmap_from_u64().

irq->wr_mask |= BIT_ULL(chan->id), use bitmap_set().

Everything will be simple and better extendable.

Frank

Quoted 70 lines

-Devendra

Quoted 66 lines

Quoted 66 lines

drivers/dma/dw-edma/dw-edma-pcie.c +5 -3

+	DECLARE_BITMAP(mask, 64);
+	unsigned long off;
 
   	if (dir == EDMA_DIR_WRITE) {
   		total = dw->wr_ch_cnt;
   		off = 0;
-		mask = dw_irq->wr_mask;
+		bitmap_from_u64(mask, dw_irq->wr_mask);
   	} else {
   		total = dw->rd_ch_cnt;
   		off = dw->wr_ch_cnt;
-		mask = dw_irq->rd_mask;
+		bitmap_from_u64(mask, dw_irq->rd_mask);
   	}
 
-	for_each_set_bit(pos, &mask, total) {
+	for_each_set_bit(pos, mask, total) {
   		chan = &dw->chan[pos + off];
 
   		val = dw_hdma_v0_core_status_int(chan);

drivers/dma/dw-edma/dw-hdma-v0-regs.h +1 -1

index 7759ba9b4850..48e40efceb2e 100644
@@ -11,7 +11,7 @@
 
   #include <linux/dmaengine.h>
 
-#define HDMA_V0_MAX_NR_CH			8
+#define HDMA_V0_MAX_NR_CH			64
   #define HDMA_V0_CH_EN				BIT(0)
   #define HDMA_V0_LOCAL_ABORT_INT_EN		BIT(6)
   #define HDMA_V0_REMOTE_ABORT_INT_EN		BIT(5)

include/linux/dma/edma.h +6 -5

index 1fafd5b0e315..da7a5cc93ad4 100644
@@ -14,6 +14,8 @@
 
   #define EDMA_MAX_WR_CH                                  8
   #define EDMA_MAX_RD_CH                                  8
+#define HDMA_MAX_WR_CH                                  64
+#define HDMA_MAX_RD_CH                                  64
 
   struct dw_edma;
 

@@ -89,12 +91,12 @@ struct dw_edma_chip {
   	u16			ll_wr_cnt;
   	u16			ll_rd_cnt;
   	/* link list address */
-	struct dw_edma_region	ll_region_wr[EDMA_MAX_WR_CH];
-	struct dw_edma_region	ll_region_rd[EDMA_MAX_RD_CH];
+	struct dw_edma_region	ll_region_wr[HDMA_MAX_WR_CH];
+	struct dw_edma_region	ll_region_rd[HDMA_MAX_RD_CH];
 
   	/* data region */
-	struct dw_edma_region	dt_region_wr[EDMA_MAX_WR_CH];
-	struct dw_edma_region	dt_region_rd[EDMA_MAX_RD_CH];
+	struct dw_edma_region	dt_region_wr[HDMA_MAX_WR_CH];
+	struct dw_edma_region	dt_region_rd[HDMA_MAX_RD_CH];
 
   	/* interrupt emulation */
   	int			db_irq;
--

2.43.0