[PATCH v5 0/5] dmaengine: arm-dma350: Add slave support and Sky1 integration

[PATCH v5 0/5] dmaengine: arm-dma350: Add slave support and Sky1 integration

[Jelly Jia]

Hello,

This series adds scatter-gather and cyclic slave transfer support to the
Arm DMA-350 driver, then describes the clock, reset and DMA address view
of the CIX Sky1 FCH integration.

Patch 1 fixes the source-trigger bit. Patch 2 adds peripheral transfers
with descriptor-owned resource mappings, coherent linked commands and
hardware-based residue reporting. Patches 3 and 4 document and handle
optional integration clocks and resets. Patch 5 describes the FCH DMA
address windows and adds its bus clock.

The controller nodes use arm,dma-350. The driver changes use standard
integration resources and introduce no CIX-specific register programming.
The companion AUDSS interrupt-path series builds on this one and manages
the AUDSS interrupt gates in the CRU driver.

Changes since v4:
- Allow slave configuration updates while descriptors exist, and take a
  locked configuration snapshot when preparing transfers. (Sashiko.)
- Derive cyclic residue from the hardware link pointer rather than a
  software period count. Retry changed samples and retain cached residue
  when a usable sample is not obtained. (Sashiko.)
- Stop advertising undefined bus widths; validate trigger support and
  transfer widths per channel and report per-channel capabilities.
  (Sashiko.)
- Remove the stopping flag and always poll STOPCMD during synchronization.
  Serialize IRQ status sampling, acknowledgement and descriptor selection
  under the channel lock. (Sashiko.)
- After dmaengine_terminate_async(), the DMAengine API requires clients to
  call dmaengine_synchronize() before issuing new transfers. The start path
  continues to rely on that requirement. (Sashiko.)
- Rebase onto Linux 7.4-rc1 and regenerate DTS context on the clean base.
  Keep patch 1 unchanged and retain Frank's Reviewed-by.

Link: https://lore.kernel.org/r/20261023093017.3248454-1-Jelly.Jia@cixtech.com

Signed-off-by: Jelly Jia <Jelly.Jia@cixtech.com>

Jelly Jia (5):
  dmaengine: arm-dma350: Fix source trigger bit
  dmaengine: arm-dma350: Add slave and cyclic transfer support
  dt-bindings: dma: arm,dma-350: Document optional clocks and resets
  dmaengine: arm-dma350: Support integration clocks and resets
  arm64: dts: cix: Describe the Sky1 FCH DMA-350 integration

 .../devicetree/bindings/dma/arm,dma-350.yaml  |  16 +-
 arch/arm64/boot/dts/cix/sky1.dtsi             |  36 +-
 drivers/dma/arm-dma350.c                      | 821 +++++++++++++++++-
 3 files changed, 828 insertions(+), 45 deletions(-)


base-commit: 6628e7d4c6b25c8d18f1345e3a20d21829aae7e4
-- 
2.54.0

[PATCH v5 1/5] dmaengine: arm-dma350: Fix source trigger bit

[Jelly Jia]

CH_CTRL_USESRCTRIGIN is the source trigger enable bit in CH_CTRL and must
use bit 25, not bit 26 which is the destination trigger enable bit
(CH_CTRL_USEDESTRIGIN).

The constant has no users yet, but enabling the source trigger input
would silently enable the destination trigger input instead, breaking
any transfer that waits for a peripheral request. Fix it before the
first user arrives.

Fixes: 5d099706449d ("dmaengine: Add Arm DMA-350 driver")
Signed-off-by: Jelly Jia <Jelly.Jia@cixtech.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
---
 drivers/dma/arm-dma350.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/dma/arm-dma350.c b/drivers/dma/arm-dma350.c
index 52f5242ea332..fdc4cd224579 100644
--- a/drivers/dma/arm-dma350.c
+++ b/drivers/dma/arm-dma350.c
@@ -63,7 +63,7 @@
 
 #define CH_CTRL			0x0c
 #define CH_CTRL_USEDESTRIGIN	BIT(26)
-#define CH_CTRL_USESRCTRIGIN	BIT(26)
+#define CH_CTRL_USESRCTRIGIN	BIT(25)
 #define CH_CTRL_DONETYPE	GENMASK(23, 21)
 #define CH_CTRL_REGRELOADTYPE	GENMASK(20, 18)
 #define CH_CTRL_XTYPE		GENMASK(11, 9)
-- 
2.54.0

[PATCH v5 2/5] dmaengine: arm-dma350: Add slave and cyclic transfer support

[Jelly Jia]

The driver currently supports memory-to-memory transfers only. Add
peripheral scatter-gather and cyclic transfers in both directions, with
trigger configuration, period callbacks and residue reporting.

Keep each peripheral DMA mapping for the lifetime of its descriptor so
preparing another transfer cannot invalidate a queued mapping. Allocate
linked commands from a coherent DMA pool to respect the controller's DMA
ranges and permit freeing them from the virt-dma tasklet. Store commands
in little-endian format and order writes before publishing them.

Set the trigger block size from maxburst in both directions. Sample the
link pointer around the hardware residue counters and retain the cached
residue if the channel advances during sampling. Include submitted
descriptors in status queries and protect slave configuration updates
with the channel lock.

Check DMA mask setup and register the OF DMA provider only for OF-backed
devices. During teardown, request channel stop and poll STOPCMD with a
bounded timeout. Warn on timeout but continue IRQ and virt-dma cleanup;
this is best-effort teardown, not confirmation that hardware has stopped.

Signed-off-by: Jelly Jia <Jelly.Jia@cixtech.com>
---
 drivers/dma/arm-dma350.c | 805 +++++++++++++++++++++++++++++++++++++--
 1 file changed, 776 insertions(+), 29 deletions(-)

diff --git a/drivers/dma/arm-dma350.c b/drivers/dma/arm-dma350.c
index fdc4cd224579..cfe3bacfab68 100644
--- a/drivers/dma/arm-dma350.c
+++ b/drivers/dma/arm-dma350.c
@@ -3,12 +3,19 @@
 // Arm DMA-350 driver
 
 #include <linux/bitfield.h>
+#include <linux/bitops.h>
 #include <linux/dmaengine.h>
 #include <linux/dma-mapping.h>
+#include <linux/dmapool.h>
 #include <linux/io.h>
+#include <linux/iopoll.h>
 #include <linux/of.h>
+#include <linux/of_dma.h>
 #include <linux/module.h>
+#include <linux/overflow.h>
 #include <linux/platform_device.h>
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
 
 #include "dmaengine.h"
 #include "virt-dma.h"
@@ -47,6 +54,8 @@
 #define CH_CMD_CLEAR		BIT(1)
 #define CH_CMD_ENABLE		BIT(0)
 
+#define D350_STOP_TIMEOUT_US	10000
+
 #define CH_STATUS		0x04
 #define CH_STAT_RESUMEWAIT	BIT(21)
 #define CH_STAT_PAUSED		BIT(20)
@@ -102,6 +111,10 @@
 #define CH_FILLVAL		0x38
 #define CH_SRCTRIGINCFG		0x4c
 #define CH_DESTRIGINCFG		0x50
+#define CH_TRIGINCFG_BLKSIZE	GENMASK(23, 16)
+#define CH_TRIGINCFG_MODE	GENMASK(11, 10)
+#define CH_TRIGINCFG_TYPE	GENMASK(9, 8)
+#define CH_TRIGINCFG_SEL	GENMASK(7, 0)
 #define CH_LINKATTR		0x70
 #define CH_LINK_SHAREATTR	GENMASK(9, 8)
 #define CH_LINK_MEMATTR		GENMASK(7, 0)
@@ -147,6 +160,7 @@
 #define LINK_LINKADDR		BIT(30)
 #define LINK_LINKADDRHI		BIT(31)
 
+#define D350_SLAVE_CMD_WORDS	14
 
 enum ch_ctrl_donetype {
 	CH_CTRL_DONETYPE_NONE = 0,
@@ -161,6 +175,18 @@ enum ch_ctrl_xtype {
 	CH_CTRL_XTYPE_FILL = 3
 };
 
+enum ch_trigincfg_mode {
+	CH_TRIGINCFG_MODE_COMMAND = 0,
+	CH_TRIGINCFG_MODE_DMA_FC = 2,
+	CH_TRIGINCFG_MODE_PERIPH_FC = 3
+};
+
+enum ch_trigincfg_type {
+	CH_TRIGINCFG_TYPE_SW = 0,
+	CH_TRIGINCFG_TYPE_HW = 2,
+	CH_TRIGINCFG_TYPE_INTERNAL = 3
+};
+
 enum ch_cfg_shareattr {
 	SHAREATTR_NSH = 0,
 	SHAREATTR_OSH = 2,
@@ -173,12 +199,28 @@ enum ch_cfg_memattr {
 	MEMATTR_WB = 0xff
 };
 
+struct d350_hw_cmd {
+	__le32 *words;
+	dma_addr_t dma;
+};
+
 struct d350_desc {
 	struct virt_dma_desc vd;
 	u32 command[16];
 	u16 xsize;
 	u16 xsizehi;
+	dma_addr_t resource_dma;
+	size_t resource_size;
+	enum dma_data_direction resource_dir;
+	bool resource_mapped;
+	struct d350_hw_cmd *cmds;
+	u32 *cmd_len;
+	size_t ncmds;
+	size_t bytes;
+	size_t period_len;
+	size_t periods;
 	u8 tsz;
+	bool cyclic;
 };
 
 struct d350_chan {
@@ -189,14 +231,17 @@ struct d350_chan {
 	enum dma_status status;
 	dma_cookie_t cookie;
 	u32 residue;
+	u32 req;
 	u8 tsz;
 	bool has_trig;
 	bool has_wrap;
 	bool coherent;
+	struct dma_slave_config sconfig;
 };
 
 struct d350 {
 	struct dma_device dma;
+	struct dma_pool *cmd_pool;
 	int nchan;
 	int nreq;
 	struct d350_chan channels[] __counted_by(nchan);
@@ -207,14 +252,489 @@ static inline struct d350_chan *to_d350_chan(struct dma_chan *chan)
 	return container_of(chan, struct d350_chan, vc.chan);
 }
 
+static inline struct d350 *d350_chan_to_dmac(struct d350_chan *dch)
+{
+	return container_of(dch->vc.chan.device, struct d350, dma);
+}
+
 static inline struct d350_desc *to_d350_desc(struct virt_dma_desc *vd)
 {
 	return container_of(vd, struct d350_desc, vd);
 }
 
+static void d350_unmap_resource(struct device *dev, struct d350_desc *desc)
+{
+	if (!desc->resource_mapped)
+		return;
+
+	dma_unmap_resource(dev, desc->resource_dma, desc->resource_size,
+			   desc->resource_dir, 0);
+	desc->resource_mapped = false;
+}
+
+static void d350_free_cmds(struct d350 *dmac, struct d350_desc *desc)
+{
+	size_t i;
+
+	for (i = 0; i < desc->ncmds; i++) {
+		if (desc->cmds[i].words)
+			dma_pool_free(dmac->cmd_pool, desc->cmds[i].words,
+				      desc->cmds[i].dma);
+	}
+
+	kfree(desc->cmds);
+	kfree(desc->cmd_len);
+}
+
 static void d350_desc_free(struct virt_dma_desc *vd)
 {
-	kfree(to_d350_desc(vd));
+	struct d350_desc *desc = to_d350_desc(vd);
+	struct device *dev = vd->tx.chan->device->dev;
+	struct d350 *dmac = d350_chan_to_dmac(to_d350_chan(vd->tx.chan));
+
+	d350_unmap_resource(dev, desc);
+	d350_free_cmds(dmac, desc);
+	kfree(desc);
+}
+
+static int d350_alloc_cmds(struct dma_chan *dchan, struct d350_desc *desc,
+			   size_t ncmds)
+{
+	struct d350 *dmac = d350_chan_to_dmac(to_d350_chan(dchan));
+	size_t i;
+
+	desc->cmds = kcalloc(ncmds, sizeof(*desc->cmds), GFP_NOWAIT);
+	if (!desc->cmds)
+		return -ENOMEM;
+
+	desc->ncmds = ncmds;
+	for (i = 0; i < ncmds; i++) {
+		desc->cmds[i].words = dma_pool_alloc(dmac->cmd_pool, GFP_NOWAIT,
+						     &desc->cmds[i].dma);
+		if (!desc->cmds[i].words) {
+			d350_free_cmds(dmac, desc);
+			desc->cmds = NULL;
+			desc->ncmds = 0;
+			return -ENOMEM;
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * The command pool is coherent, but order the command writes before the
+ * descriptor can be submitted and started by another CPU.
+ */
+static void d350_sync_cmds(struct d350_desc *desc)
+{
+	if (!desc->cmds)
+		return;
+
+	dma_wmb();
+}
+
+static dma_addr_t d350_map_resource(struct dma_chan *dchan,
+				    struct d350_desc *desc,
+				    phys_addr_t cpu_addr, size_t size,
+				    enum dma_data_direction dir)
+{
+	struct device *dev = dchan->device->dev;
+	dma_addr_t dma_addr;
+
+	dma_addr = dma_map_resource(dev, cpu_addr, size, dir, 0);
+	if (dma_mapping_error(dev, dma_addr)) {
+		dev_err(dev, "map slave failed ch%u phys=%pa size=%zu dir=%d\n",
+			dchan->chan_id, &cpu_addr, size, dir);
+		return DMA_MAPPING_ERROR;
+	}
+
+	desc->resource_dma = dma_addr;
+	desc->resource_size = size;
+	desc->resource_dir = dir;
+	desc->resource_mapped = true;
+
+	return dma_addr;
+}
+
+static bool d350_buswidth_supported(u32 widths, enum dma_slave_buswidth width)
+{
+	return width < BITS_PER_TYPE(widths) && (widths & BIT(width));
+}
+
+static bool d350_slave_supported(struct d350_chan *dch)
+{
+	return dch->has_trig && d350_chan_to_dmac(dch)->nreq > 0;
+}
+
+static u32 d350_chan_widths(struct d350_chan *dch)
+{
+	struct dma_device *dma = dch->vc.chan.device;
+	u32 widths = dma->src_addr_widths | dma->dst_addr_widths;
+
+	return widths & GENMASK(min_t(unsigned int, BIT(dch->tsz),
+				     BITS_PER_TYPE(widths) - 1), 1);
+}
+
+static void d350_caps(struct dma_chan *chan, struct dma_slave_caps *caps)
+{
+	struct d350_chan *dch = to_d350_chan(chan);
+	u32 widths = d350_chan_widths(dch);
+
+	caps->src_addr_widths &= widths;
+	caps->dst_addr_widths &= widths;
+	if (!d350_slave_supported(dch))
+		caps->directions &= ~(BIT(DMA_MEM_TO_DEV) | BIT(DMA_DEV_TO_MEM));
+}
+
+static int d350_check_slave_config(struct d350_chan *dch,
+				   struct dma_slave_config *config)
+{
+	u32 maxburst = FIELD_MAX(CH_CFG_MAXBURSTLEN) + 1;
+	u32 widths = d350_chan_widths(dch);
+
+	if (!d350_slave_supported(dch))
+		return -EOPNOTSUPP;
+
+	/* The unused direction may leave its bus width unspecified. */
+	if ((config->src_addr_width != DMA_SLAVE_BUSWIDTH_UNDEFINED &&
+	     !d350_buswidth_supported(widths, config->src_addr_width)) ||
+	    (config->dst_addr_width != DMA_SLAVE_BUSWIDTH_UNDEFINED &&
+	     !d350_buswidth_supported(widths, config->dst_addr_width)))
+		return -EINVAL;
+
+	if (config->src_maxburst > maxburst ||
+	    config->dst_maxburst > maxburst)
+		return -EINVAL;
+
+	return 0;
+}
+
+static int d350_config(struct dma_chan *chan, struct dma_slave_config *config)
+{
+	struct d350_chan *dch = to_d350_chan(chan);
+	struct dma_device *dma = chan->device;
+	unsigned long flags;
+	int ret;
+
+	ret = d350_check_slave_config(dch, config);
+	if (ret) {
+		dev_err(dma->dev, "invalid slave configuration\n");
+		return ret;
+	}
+
+	spin_lock_irqsave(&dch->vc.lock, flags);
+	dch->sconfig = *config;
+	spin_unlock_irqrestore(&dch->vc.lock, flags);
+
+	return 0;
+}
+
+static struct dma_chan *d350_of_xlate(struct of_phandle_args *dma_spec,
+				      struct of_dma *ofdma)
+{
+	struct d350 *dmac = ofdma->of_dma_data;
+	struct d350_chan *dch;
+	struct dma_chan *chan;
+	u32 req;
+	int i;
+
+	if (dma_spec->args_count != 1) {
+		dev_err(dmac->dma.dev, "dma phandle must have one argument\n");
+		return NULL;
+	}
+
+	req = dma_spec->args[0];
+	if (req >= dmac->nreq) {
+		dev_err(dmac->dma.dev, "invalid DMA request %u, have %d\n",
+			req, dmac->nreq);
+		return NULL;
+	}
+
+	for (i = 0; i < dmac->nchan; i++) {
+		dch = &dmac->channels[i];
+		if (!dch->has_trig)
+			continue;
+
+		chan = dma_get_slave_channel(&dch->vc.chan);
+		if (chan) {
+			dch->req = req;
+			return chan;
+		}
+	}
+
+	dev_err(dmac->dma.dev, "no free channel with trigger support\n");
+
+	return NULL;
+}
+
+static u32 d350_device_transcfg(u32 maxburst)
+{
+	return FIELD_PREP(CH_CFG_MAXBURSTLEN, maxburst - 1) |
+	       FIELD_PREP(CH_CFG_SHAREATTR, SHAREATTR_OSH) |
+	       FIELD_PREP(CH_CFG_MEMATTR, MEMATTR_DEVICE);
+}
+
+static int d350_slave_params(struct d350_chan *dch,
+			     enum dma_transfer_direction direction,
+			     phys_addr_t *dev_cpu_addr,
+			     enum dma_data_direction *dev_dir,
+			     enum dma_slave_buswidth *width, u32 *maxburst)
+{
+	struct dma_slave_config config;
+	unsigned long flags;
+	int ret;
+
+	spin_lock_irqsave(&dch->vc.lock, flags);
+	config = dch->sconfig;
+	spin_unlock_irqrestore(&dch->vc.lock, flags);
+
+	ret = d350_check_slave_config(dch, &config);
+	if (ret)
+		return ret;
+	if (dch->req >= d350_chan_to_dmac(dch)->nreq)
+		return -EINVAL;
+
+	if (direction == DMA_MEM_TO_DEV) {
+		*dev_cpu_addr = config.dst_addr;
+		*dev_dir = DMA_FROM_DEVICE;
+		*width = config.dst_addr_width;
+		*maxburst = config.dst_maxburst;
+	} else if (direction == DMA_DEV_TO_MEM) {
+		*dev_cpu_addr = config.src_addr;
+		*dev_dir = DMA_TO_DEVICE;
+		*width = config.src_addr_width;
+		*maxburst = config.src_maxburst;
+	} else {
+		return -EINVAL;
+	}
+
+	return *width && *maxburst ? 0 : -EINVAL;
+}
+
+static void d350_fill_slave_cmd(struct d350_chan *dch, struct d350_desc *desc,
+				u32 *cmd, dma_addr_t mem, dma_addr_t dev_dma_addr,
+				size_t len, bool link, dma_addr_t link_addr,
+				enum dma_transfer_direction direction,
+				enum dma_slave_buswidth width, u32 maxburst,
+				enum ch_ctrl_donetype donetype)
+{
+	bool mem_to_dev = direction == DMA_MEM_TO_DEV;
+	u16 xsize;
+	u16 xsizehi;
+	u32 devcfg;
+	u32 memcfg;
+	u32 trigcfg;
+
+	desc->tsz = __ffs(width);
+	xsize = lower_16_bits(len >> desc->tsz);
+	xsizehi = upper_16_bits(len >> desc->tsz);
+	devcfg = d350_device_transcfg(maxburst);
+	memcfg = dch->coherent ? TRANSCFG_WB : TRANSCFG_NC;
+
+	trigcfg = FIELD_PREP(CH_TRIGINCFG_BLKSIZE, maxburst - 1) |
+		  FIELD_PREP(CH_TRIGINCFG_MODE, CH_TRIGINCFG_MODE_PERIPH_FC) |
+		  FIELD_PREP(CH_TRIGINCFG_TYPE, CH_TRIGINCFG_TYPE_HW) |
+		  FIELD_PREP(CH_TRIGINCFG_SEL, dch->req);
+
+	cmd[0] = LINK_CTRL | LINK_SRCADDR | LINK_SRCADDRHI | LINK_DESADDR |
+		 LINK_DESADDRHI | LINK_XSIZE | LINK_XSIZEHI | LINK_SRCTRANSCFG |
+		 LINK_DESTRANSCFG | LINK_XADDRINC | LINK_LINKADDR |
+		 LINK_LINKADDRHI |
+		 (mem_to_dev ? LINK_DESTRIGINCFG : LINK_SRCTRIGINCFG);
+	cmd[1] = (mem_to_dev ? CH_CTRL_USEDESTRIGIN : CH_CTRL_USESRCTRIGIN) |
+		 FIELD_PREP(CH_CTRL_TRANSIZE, desc->tsz) |
+		 FIELD_PREP(CH_CTRL_XTYPE, CH_CTRL_XTYPE_CONTINUE) |
+		 FIELD_PREP(CH_CTRL_DONETYPE, donetype);
+	cmd[2] = lower_32_bits(mem_to_dev ? mem : dev_dma_addr);
+	cmd[3] = upper_32_bits(mem_to_dev ? mem : dev_dma_addr);
+	cmd[4] = lower_32_bits(mem_to_dev ? dev_dma_addr : mem);
+	cmd[5] = upper_32_bits(mem_to_dev ? dev_dma_addr : mem);
+	cmd[6] = FIELD_PREP(CH_XY_SRC, xsize) |
+		 FIELD_PREP(CH_XY_DES, xsize);
+	cmd[7] = FIELD_PREP(CH_XY_SRC, xsizehi) |
+		 FIELD_PREP(CH_XY_DES, xsizehi);
+	cmd[8] = mem_to_dev ? memcfg : devcfg;
+	cmd[9] = mem_to_dev ? devcfg : memcfg;
+	cmd[10] = mem_to_dev ? FIELD_PREP(CH_XY_SRC, 1) :
+				FIELD_PREP(CH_XY_DES, 1);
+	cmd[11] = trigcfg;
+	cmd[12] = lower_32_bits(link_addr) | (link ? CH_LINKADDR_EN : 0);
+	cmd[13] = upper_32_bits(link_addr);
+}
+
+static void d350_store_slave_cmd(__le32 *dst, const u32 *src)
+{
+	int i;
+
+	for (i = 0; i < D350_SLAVE_CMD_WORDS; i++)
+		dst[i] = cpu_to_le32(src[i]);
+}
+
+static struct dma_async_tx_descriptor *
+d350_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
+		   unsigned int sg_len,
+		   enum dma_transfer_direction direction,
+		   unsigned long flags, void *context)
+{
+	struct d350_chan *dch = to_d350_chan(dchan);
+	size_t cmd_size = D350_SLAVE_CMD_WORDS * sizeof(u32);
+	enum dma_data_direction dev_dir;
+	enum dma_slave_buswidth width;
+	struct d350_desc *desc;
+	phys_addr_t dev_cpu_addr;
+	dma_addr_t dev_dma_addr;
+	dma_addr_t mem;
+	struct scatterlist *sg;
+	u32 maxburst;
+	size_t len;
+	int i;
+
+	if (unlikely(!is_slave_direction(direction) || !sg_len))
+		return NULL;
+
+	if (d350_slave_params(dch, direction, &dev_cpu_addr, &dev_dir, &width,
+			      &maxburst))
+		return NULL;
+
+	desc = kzalloc_obj(*desc, GFP_NOWAIT);
+	if (!desc)
+		return NULL;
+
+	dev_dma_addr = d350_map_resource(dchan, desc, dev_cpu_addr, width,
+					 dev_dir);
+	if (dma_mapping_error(dchan->device->dev, dev_dma_addr))
+		goto err_free_desc;
+
+	if (sg_len > 1) {
+		if (d350_alloc_cmds(dchan, desc, sg_len))
+			goto err_free_desc;
+
+		desc->cmd_len = kcalloc(sg_len, sizeof(*desc->cmd_len),
+					GFP_NOWAIT);
+		if (!desc->cmd_len)
+			goto err_free_cmds;
+	}
+
+	for_each_sg(sgl, sg, sg_len, i) {
+		enum ch_ctrl_donetype donetype = CH_CTRL_DONETYPE_CMD;
+		u32 command[D350_SLAVE_CMD_WORDS];
+		dma_addr_t link_addr = 0;
+		bool link = false;
+		u32 *cmd = desc->command;
+
+		mem = sg_dma_address(sg);
+		len = sg_dma_len(sg);
+		if (!len || (len >> __ffs(width)) > U32_MAX ||
+		    !IS_ALIGNED(len | mem | dev_dma_addr, width))
+			goto err_free_cmds;
+
+		if (sg_len > 1) {
+			cmd = command;
+			if (i < sg_len - 1) {
+				link = true;
+				link_addr = desc->cmds[i + 1].dma;
+				donetype = CH_CTRL_DONETYPE_NONE;
+			}
+			desc->cmd_len[i] = len;
+		}
+
+		if (check_add_overflow(desc->bytes, len, &desc->bytes) ||
+		    desc->bytes > U32_MAX)
+			goto err_free_cmds;
+
+		d350_fill_slave_cmd(dch, desc, cmd, mem, dev_dma_addr, len,
+				    link, link_addr, direction, width, maxburst,
+				    donetype);
+		if (sg_len > 1) {
+			d350_store_slave_cmd(desc->cmds[i].words, cmd);
+			if (!i)
+				memcpy(desc->command, cmd, cmd_size);
+		}
+	}
+
+	d350_sync_cmds(desc);
+
+	return vchan_tx_prep(&dch->vc, &desc->vd, flags);
+
+err_free_cmds:
+	d350_free_cmds(d350_chan_to_dmac(dch), desc);
+err_free_desc:
+	d350_unmap_resource(dchan->device->dev, desc);
+	kfree(desc);
+
+	return NULL;
+}
+
+static struct dma_async_tx_descriptor *
+d350_prep_dma_cyclic(struct dma_chan *dchan, dma_addr_t buf_addr,
+		     size_t buf_len, size_t period_len,
+		     enum dma_transfer_direction direction, unsigned long flags)
+{
+	struct d350_chan *dch = to_d350_chan(dchan);
+	struct d350_desc *desc;
+	phys_addr_t dev_cpu_addr;
+	dma_addr_t dev_dma_addr;
+	enum dma_data_direction dev_dir;
+	enum dma_slave_buswidth width;
+	size_t period;
+	size_t cmd_size;
+	u32 maxburst;
+	int ret;
+
+	if (!buf_len || !period_len || buf_len % period_len ||
+	    buf_len > U32_MAX || !is_slave_direction(direction))
+		return NULL;
+
+	ret = d350_slave_params(dch, direction, &dev_cpu_addr, &dev_dir, &width,
+				&maxburst);
+	if (ret)
+		return NULL;
+
+	desc = kzalloc_obj(*desc, GFP_NOWAIT);
+	if (!desc)
+		return NULL;
+
+	dev_dma_addr = d350_map_resource(dchan, desc, dev_cpu_addr, width,
+					 dev_dir);
+	if (dma_mapping_error(dchan->device->dev, dev_dma_addr))
+		goto err_free_desc;
+
+	if (!IS_ALIGNED(buf_addr | dev_dma_addr | period_len, width))
+		goto err_free_desc;
+
+	desc->bytes = buf_len;
+	desc->period_len = period_len;
+	desc->periods = buf_len / period_len;
+	desc->cyclic = true;
+
+	if (d350_alloc_cmds(dchan, desc, desc->periods))
+		goto err_free_desc;
+
+	cmd_size = D350_SLAVE_CMD_WORDS * sizeof(u32);
+
+	for (period = 0; period < desc->periods; period++) {
+		u32 command[D350_SLAVE_CMD_WORDS];
+		dma_addr_t mem = buf_addr + period * period_len;
+		dma_addr_t next = desc->cmds[(period + 1) % desc->periods].dma;
+
+		d350_fill_slave_cmd(dch, desc, command, mem, dev_dma_addr,
+				    period_len, true, next, direction, width,
+				    maxburst, CH_CTRL_DONETYPE_CMD);
+		d350_store_slave_cmd(desc->cmds[period].words, command);
+		if (!period)
+			memcpy(desc->command, command, cmd_size);
+	}
+
+	d350_sync_cmds(desc);
+
+	return vchan_tx_prep(&dch->vc, &desc->vd, flags);
+
+err_free_desc:
+	d350_unmap_resource(dchan->device->dev, desc);
+	kfree(desc);
+
+	return NULL;
 }
 
 static struct dma_async_tx_descriptor *d350_prep_memcpy(struct dma_chan *chan,
@@ -228,6 +748,7 @@ static struct dma_async_tx_descriptor *d350_prep_memcpy(struct dma_chan *chan,
 	if (!desc)
 		return NULL;
 
+	desc->bytes = len;
 	desc->tsz = __ffs(len | dest | src | (1 << dch->tsz));
 	desc->xsize = lower_16_bits(len >> desc->tsz);
 	desc->xsizehi = upper_16_bits(len >> desc->tsz);
@@ -266,6 +787,7 @@ static struct dma_async_tx_descriptor *d350_prep_memset(struct dma_chan *chan,
 	if (!desc)
 		return NULL;
 
+	desc->bytes = len;
 	desc->tsz = __ffs(len | dest | (1 << dch->tsz));
 	desc->xsize = lower_16_bits(len >> desc->tsz);
 	desc->xsizehi = upper_16_bits(len >> desc->tsz);
@@ -339,6 +861,69 @@ static u32 d350_get_residue(struct d350_chan *dch)
 	return res << dch->desc->tsz;
 }
 
+static u32 d350_get_sg_residue(struct d350_chan *dch)
+{
+	struct d350_desc *desc = dch->desc;
+	size_t cmd = 0;
+	size_t i;
+	u32 linkaddr;
+	u32 linkaddrhi;
+	u32 hi_new;
+	u32 lo_new;
+	u32 residue;
+	u64 next_cmd;
+	int retries = 3;
+
+	if (!desc->cmd_len)
+		return d350_get_residue(dch);
+
+	/*
+	 * CH_LINKADDR points at the next command. Match it against the command
+	 * array to find the command currently executing, then add every later
+	 * command which has not started yet.
+	 */
+	/* The channel may step the link pointer between the two reads */
+	hi_new = readl_relaxed(dch->base + CH_LINKADDRHI);
+	do {
+		linkaddrhi = hi_new;
+		linkaddr = readl_relaxed(dch->base + CH_LINKADDR);
+		hi_new = readl_relaxed(dch->base + CH_LINKADDRHI);
+	} while (linkaddrhi != hi_new && --retries);
+
+	next_cmd = (linkaddr & ~CH_LINKADDR_EN) | ((u64)linkaddrhi << 32);
+
+	if (!next_cmd) {
+		cmd = desc->ncmds - 1;
+	} else {
+		for (i = 1; i < desc->ncmds; i++) {
+			if (next_cmd == desc->cmds[i].dma) {
+				cmd = i - 1;
+				break;
+			}
+		}
+		if (i == desc->ncmds)
+			return dch->residue;
+	}
+
+	residue = d350_get_residue(dch);
+
+	/*
+	 * If the channel stepped to the next command while CH_XSIZE was read,
+	 * the size belongs to the command which just finished and the sum below
+	 * would count the bytes left in it twice. Keep the residue from the last
+	 * completion in that case.
+	 */
+	hi_new = readl_relaxed(dch->base + CH_LINKADDRHI);
+	lo_new = readl_relaxed(dch->base + CH_LINKADDR);
+	if (hi_new != linkaddrhi || lo_new != linkaddr)
+		return dch->residue;
+
+	for (i = cmd + 1; i < desc->ncmds; i++)
+		residue += desc->cmd_len[i];
+
+	return residue;
+}
+
 static int d350_terminate_all(struct dma_chan *chan)
 {
 	struct d350_chan *dch = to_d350_chan(chan);
@@ -360,16 +945,115 @@ static int d350_terminate_all(struct dma_chan *chan)
 	return 0;
 }
 
+static int d350_wait_for_stop(struct d350_chan *dch)
+{
+	u32 cmd;
+	int ret;
+
+	/* STOPCMD clears only after the channel has stopped using commands. */
+	ret = readl_poll_timeout(dch->base + CH_CMD, cmd,
+				 !(cmd & CH_CMD_STOP), 10,
+				 D350_STOP_TIMEOUT_US);
+	if (ret)
+		dev_warn(dch->vc.chan.device->dev,
+			 "channel %d failed to stop\n", dch->vc.chan.chan_id);
+
+	return ret;
+}
+
 static void d350_synchronize(struct dma_chan *chan)
 {
 	struct d350_chan *dch = to_d350_chan(chan);
 
+	/* A stop timeout must not skip IRQ or callback synchronization. */
+	d350_wait_for_stop(dch);
+	synchronize_irq(dch->irq);
 	vchan_synchronize(&dch->vc);
 }
 
 static u32 d350_desc_bytes(struct d350_desc *desc)
 {
-	return ((u32)desc->xsizehi << 16 | desc->xsize) << desc->tsz;
+	return desc->bytes;
+}
+
+static u32 d350_get_cyclic_residue(struct d350_chan *dch)
+{
+	struct d350_desc *desc = dch->desc;
+	size_t period;
+	size_t next;
+	u32 linkaddr;
+	u32 linkaddrhi;
+	u32 xsize;
+	u32 xsizehi;
+	u32 hi_new;
+	u32 lo_new;
+	u64 next_cmd;
+	u64 remaining;
+	int retries = 3;
+
+	/*
+	 * Locate the current period from the next command's address rather than
+	 * counting interrupts, since multiple period completions may share a
+	 * pending DONE interrupt.
+	 */
+	do {
+		linkaddrhi = readl_relaxed(dch->base + CH_LINKADDRHI);
+		linkaddr = readl_relaxed(dch->base + CH_LINKADDR);
+		hi_new = readl_relaxed(dch->base + CH_LINKADDRHI);
+		if (linkaddrhi != hi_new)
+			continue;
+
+		xsizehi = readl_relaxed(dch->base + CH_XSIZEHI);
+		xsize = readl_relaxed(dch->base + CH_XSIZE);
+		hi_new = readl_relaxed(dch->base + CH_XSIZEHI);
+		if (xsizehi != hi_new)
+			continue;
+
+		/* Retry if the link changed while reading the remaining size. */
+		lo_new = readl_relaxed(dch->base + CH_LINKADDR);
+		hi_new = readl_relaxed(dch->base + CH_LINKADDRHI);
+		if (linkaddrhi != hi_new || linkaddr != lo_new)
+			continue;
+
+		next_cmd = (linkaddr & ~CH_LINKADDR_EN) |
+			   ((u64)linkaddrhi << 32);
+		for (next = 0; next < desc->periods; next++)
+			if (next_cmd == desc->cmds[next].dma)
+				break;
+		if (next == desc->periods)
+			continue;
+
+		remaining = FIELD_GET(CH_XY_DES, xsize) |
+			    ((u64)FIELD_GET(CH_XY_DES, xsizehi) << 16);
+		remaining <<= desc->tsz;
+		if (remaining > desc->period_len)
+			continue;
+
+		period = next ? next - 1 : desc->periods - 1;
+		return desc->bytes - (period + 1) * desc->period_len + remaining;
+	} while (--retries);
+
+	return dch->residue;
+}
+
+static u32 d350_get_active_residue(struct d350_chan *dch)
+{
+	if (dch->desc->cyclic)
+		return d350_get_cyclic_residue(dch);
+
+	return d350_get_sg_residue(dch);
+}
+
+static struct virt_dma_desc *d350_find_queued_desc(struct d350_chan *dch,
+						   dma_cookie_t cookie)
+{
+	struct virt_dma_desc *vd;
+
+	list_for_each_entry(vd, &dch->vc.desc_submitted, node)
+		if (vd->tx.cookie == cookie)
+			return vd;
+
+	return vchan_find_desc(&dch->vc, cookie);
 }
 
 static enum dma_status d350_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
@@ -387,13 +1071,16 @@ static enum dma_status d350_tx_status(struct dma_chan *chan, dma_cookie_t cookie
 	if (cookie == dch->cookie) {
 		status = dch->status;
 		if (status == DMA_IN_PROGRESS || status == DMA_PAUSED)
-			dch->residue = d350_get_residue(dch);
+			dch->residue = d350_get_active_residue(dch);
 		residue = dch->residue;
-	} else if ((vd = vchan_find_desc(&dch->vc, cookie))) {
-		residue = d350_desc_bytes(to_d350_desc(vd));
-	} else if (status == DMA_IN_PROGRESS) {
-		/* Somebody else terminated it? */
-		status = DMA_ERROR;
+	} else {
+		vd = d350_find_queued_desc(dch, cookie);
+		if (vd) {
+			residue = d350_desc_bytes(to_d350_desc(vd));
+		} else if (status == DMA_IN_PROGRESS) {
+			/* Somebody else terminated it? */
+			status = DMA_ERROR;
+		}
 	}
 	spin_unlock_irqrestore(&dch->vc.lock, flags);
 
@@ -469,17 +1156,36 @@ static void d350_issue_pending(struct dma_chan *chan)
 static irqreturn_t d350_irq(int irq, void *data)
 {
 	struct d350_chan *dch = data;
-	struct device *dev = dch->vc.chan.device->dev;
-	struct virt_dma_desc *vd = &dch->desc->vd;
+	struct virt_dma_desc *vd;
+	struct d350_desc *desc;
+	u32 residue = 0;
 	u32 ch_status;
+	u32 irq_status;
+	u32 errinfo = 0;
+
+	/* Keep the sampled status paired with the active descriptor. */
+	spin_lock(&dch->vc.lock);
 
 	ch_status = readl(dch->base + CH_STATUS);
-	if (!ch_status)
+	irq_status = ch_status & (CH_STAT_INTR_DONE | CH_STAT_INTR_ERR);
+	if (!irq_status) {
+		spin_unlock(&dch->vc.lock);
 		return IRQ_NONE;
+	}
+
+	/* Clearing STAT_ERR also clears CH_ERRINFO. */
+	if (irq_status & CH_STAT_INTR_ERR)
+		errinfo = readl_relaxed(dch->base + CH_ERRINFO);
 
-	if (ch_status & CH_STAT_INTR_ERR) {
-		u32 errinfo = readl_relaxed(dch->base + CH_ERRINFO);
+	writel_relaxed(ch_status & (CH_STAT_DONE | CH_STAT_ERR),
+		       dch->base + CH_STATUS);
+
+	desc = dch->desc;
+	if (!desc)
+		goto out;
 
+	vd = &desc->vd;
+	if (irq_status & CH_STAT_INTR_ERR) {
 		if (errinfo & (CH_ERRINFO_AXIRDPOISERR | CH_ERRINFO_AXIRDRESPERR))
 			vd->tx_result.result = DMA_TRANS_READ_FAILED;
 		else if (errinfo & CH_ERRINFO_AXIWRRESPERR)
@@ -487,22 +1193,28 @@ static irqreturn_t d350_irq(int irq, void *data)
 		else
 			vd->tx_result.result = DMA_TRANS_ABORTED;
 
-		vd->tx_result.residue = d350_get_residue(dch);
-	} else if (!(ch_status & CH_STAT_INTR_DONE)) {
-		dev_warn(dev, "Unexpected IRQ source? 0x%08x\n", ch_status);
-	}
-	writel_relaxed(ch_status, dch->base + CH_STATUS);
-
-	spin_lock(&dch->vc.lock);
-	vchan_cookie_complete(vd);
-	if (ch_status & CH_STAT_INTR_DONE) {
-		dch->status = DMA_COMPLETE;
-		dch->residue = 0;
-		d350_start_next(dch);
-	} else {
+		residue = d350_get_active_residue(dch);
+		vd->tx_result.residue = residue;
 		dch->status = DMA_ERROR;
-		dch->residue = vd->tx_result.residue;
+		dch->residue = residue;
+		dch->desc = NULL;
+		if (desc->cyclic)
+			vchan_terminate_vdesc(vd);
+		else
+			vchan_cookie_complete(vd);
+	} else {
+		if (desc->cyclic) {
+			dch->residue = d350_get_cyclic_residue(dch);
+			vchan_cyclic_callback(vd);
+		} else {
+			dch->status = DMA_COMPLETE;
+			dch->residue = 0;
+			dch->desc = NULL;
+			vchan_cookie_complete(vd);
+			d350_start_next(dch);
+		}
 	}
+out:
 	spin_unlock(&dch->vc.lock);
 
 	return IRQ_HANDLED;
@@ -524,7 +1236,11 @@ static void d350_free_chan_resources(struct dma_chan *chan)
 	struct d350_chan *dch = to_d350_chan(chan);
 
 	writel_relaxed(0, dch->base + CH_INTREN);
+	d350_terminate_all(chan);
+	d350_wait_for_stop(dch);
+
 	free_irq(dch->irq, dch);
+	vchan_synchronize(&dch->vc);
 	vchan_free_chan_resources(&dch->vc);
 }
 
@@ -553,7 +1269,9 @@ static int d350_probe(struct platform_device *pdev)
 	dw = 1 << FIELD_GET(DMA_CFG_DATA_WIDTH, reg);
 	aw = FIELD_GET(DMA_CFG_ADDR_WIDTH, reg) + 1;
 
-	dma_set_mask_and_coherent(dev, DMA_BIT_MASK(aw));
+	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(aw));
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to set DMA mask\n");
 	coherent = device_get_dma_attr(dev) == DEV_DMA_COHERENT;
 
 	dmac = devm_kzalloc(dev, struct_size(dmac, channels, nchan), GFP_KERNEL);
@@ -561,6 +1279,11 @@ static int d350_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	dmac->nchan = nchan;
+	dmac->cmd_pool = dmam_pool_create("dma350-cmd", dev,
+					  D350_SLAVE_CMD_WORDS * sizeof(u32),
+					  sizeof(u64), 0);
+	if (!dmac->cmd_pool)
+		return -ENOMEM;
 
 	reg = readl_relaxed(base + DMAINFO + DMA_BUILDCFG1);
 	dmac->nreq = FIELD_GET(DMA_CFG_NUM_TRIGGER_IN, reg);
@@ -579,19 +1302,23 @@ static int d350_probe(struct platform_device *pdev)
 	dmac->dma.device_free_chan_resources = d350_free_chan_resources;
 	dma_cap_set(DMA_MEMCPY, dmac->dma.cap_mask);
 	dmac->dma.device_prep_dma_memcpy = d350_prep_memcpy;
+	dmac->dma.device_prep_slave_sg = d350_prep_slave_sg;
+	dmac->dma.device_prep_dma_cyclic = d350_prep_dma_cyclic;
 	dmac->dma.device_pause = d350_pause;
 	dmac->dma.device_resume = d350_resume;
 	dmac->dma.device_terminate_all = d350_terminate_all;
 	dmac->dma.device_synchronize = d350_synchronize;
 	dmac->dma.device_tx_status = d350_tx_status;
 	dmac->dma.device_issue_pending = d350_issue_pending;
+	dmac->dma.device_config = d350_config;
+	dmac->dma.device_caps = d350_caps;
 	INIT_LIST_HEAD(&dmac->dma.channels);
 
 	reg = readl_relaxed(base + DMANSECCTRL + NSEC_CTRL);
 	writel_relaxed(reg | INTREN_ANYCHINTR_EN,
 		       base + DMANSECCTRL + NSEC_CTRL);
 
-	/* Would be nice to have per-channel caps for this... */
+	/* Advertise memset only if every usable channel supports wrap. */
 	memset = true;
 	for (int i = 0; i < nchan; i++) {
 		struct d350_chan *dch = &dmac->channels[i];
@@ -623,8 +1350,16 @@ static int d350_probe(struct platform_device *pdev)
 		reg |= FIELD_PREP(CH_LINK_MEMATTR, coherent ? MEMATTR_WB : MEMATTR_NC);
 		writel_relaxed(reg, dch->base + CH_LINKATTR);
 
+		dch->coherent = coherent;
 		dch->vc.desc_free = d350_desc_free;
 		vchan_init(&dch->vc, &dmac->dma);
+
+		if (d350_slave_supported(dch)) {
+			dma_cap_set(DMA_SLAVE, dmac->dma.cap_mask);
+			dma_cap_set(DMA_CYCLIC, dmac->dma.cap_mask);
+			dmac->dma.directions |= BIT(DMA_MEM_TO_DEV) |
+						BIT(DMA_DEV_TO_MEM);
+		}
 	}
 
 	if (memset) {
@@ -638,6 +1373,16 @@ static int d350_probe(struct platform_device *pdev)
 	if (ret)
 		return dev_err_probe(dev, ret, "Failed to register DMA device\n");
 
+	if (dev->of_node) {
+		ret = of_dma_controller_register(dev->of_node, d350_of_xlate,
+						 dmac);
+		if (ret) {
+			dma_async_device_unregister(&dmac->dma);
+			return dev_err_probe(dev, ret,
+					     "Failed to register OF DMA controller\n");
+		}
+	}
+
 	return 0;
 }
 
@@ -645,6 +1390,8 @@ static void d350_remove(struct platform_device *pdev)
 {
 	struct d350 *dmac = platform_get_drvdata(pdev);
 
+	if (pdev->dev.of_node)
+		of_dma_controller_free(pdev->dev.of_node);
 	dma_async_device_unregister(&dmac->dma);
 }
 
-- 
2.54.0

[PATCH v5 3/5] dt-bindings: dma: arm,dma-350: Document optional clocks and resets

[Jelly Jia]

Some integrations gate the DMA-350 controller with a bus clock or hold it
in reset. Sky1 provides a clock for both its FCH and AUDSS instances, and
a reset for the AUDSS instance. Document these standard resources on the
DMA controller node.

Neither property is required, so existing device trees are unchanged.

Signed-off-by: Jelly Jia <Jelly.Jia@cixtech.com>
---
 .../devicetree/bindings/dma/arm,dma-350.yaml     | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/dma/arm,dma-350.yaml b/Documentation/devicetree/bindings/dma/arm,dma-350.yaml
index 429f682f15d8..43279878207c 100644
--- a/Documentation/devicetree/bindings/dma/arm,dma-350.yaml
+++ b/Documentation/devicetree/bindings/dma/arm,dma-350.yaml
@@ -9,9 +9,6 @@ title: Arm CoreLink DMA-350 Controller
 maintainers:
   - Robin Murphy <robin.murphy@arm.com>
 
-allOf:
-  - $ref: dma-controller.yaml#
-
 properties:
   compatible:
     const: arm,dma-350
@@ -36,9 +33,22 @@ properties:
     const: 1
     description: The cell is the trigger input number
 
+  clocks:
+    maxItems: 1
+    description:
+      Optional bus clock, where the integration gates the controller clock.
+
+  resets:
+    maxItems: 1
+    description:
+      Optional reset line, where the integration exposes one.
+
 required:
   - compatible
   - reg
   - interrupts
 
+allOf:
+  - $ref: dma-controller.yaml#
+
 unevaluatedProperties: false
-- 
2.54.0

[PATCH v5 4/5] dmaengine: arm-dma350: Support integration clocks and resets

[Jelly Jia]

DMA-350 integrations may gate the controller with a clock or hold it in
reset. Enable an optional clock and deassert an optional reset before
accessing the controller registers.

Use the deasserted reset helper rather than requesting a reset pulse.
This also supports reset controllers that only implement assert and
deassert operations.

Both resources remain optional, so existing integrations without them
are unchanged.

Signed-off-by: Jelly Jia <Jelly.Jia@cixtech.com>
---
 drivers/dma/arm-dma350.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/drivers/dma/arm-dma350.c b/drivers/dma/arm-dma350.c
index cfe3bacfab68..2f22f8a0ab47 100644
--- a/drivers/dma/arm-dma350.c
+++ b/drivers/dma/arm-dma350.c
@@ -4,6 +4,7 @@
 
 #include <linux/bitfield.h>
 #include <linux/bitops.h>
+#include <linux/clk.h>
 #include <linux/dmaengine.h>
 #include <linux/dma-mapping.h>
 #include <linux/dmapool.h>
@@ -14,6 +15,7 @@
 #include <linux/module.h>
 #include <linux/overflow.h>
 #include <linux/platform_device.h>
+#include <linux/reset.h>
 #include <linux/scatterlist.h>
 #include <linux/slab.h>
 
@@ -1247,12 +1249,24 @@ static void d350_free_chan_resources(struct dma_chan *chan)
 static int d350_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
+	struct reset_control *reset;
+	struct clk *clk;
 	struct d350 *dmac;
 	void __iomem *base;
 	u32 reg;
 	int ret, nchan, dw, aw, r, p;
 	bool coherent, memset;
 
+	clk = devm_clk_get_optional_enabled(dev, NULL);
+	if (IS_ERR(clk))
+		return dev_err_probe(dev, PTR_ERR(clk),
+				     "failed to enable clock\n");
+
+	reset = devm_reset_control_get_optional_exclusive_deasserted(dev, NULL);
+	if (IS_ERR(reset))
+		return dev_err_probe(dev, PTR_ERR(reset),
+				     "failed to deassert reset\n");
+
 	base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(base))
 		return PTR_ERR(base);
-- 
2.54.0

[PATCH v5 5/5] arm64: dts: cix: Describe the Sky1 FCH DMA-350 integration

[Jelly Jia]

The FCH DMA-350 master accesses the CPU physical peripheral window at
0x040b0000 through DMA address 0x040a0000. Describe this fixed translation
and the reachable DRAM windows with dma-ranges on the parent simple-bus.
The CPU register address view remains unchanged.

Keep the existing controller register region and eight interrupt
specifiers, and add its SCMI bus clock.

Signed-off-by: Jelly Jia <Jelly.Jia@cixtech.com>
---
 arch/arm64/boot/dts/cix/sky1.dtsi | 36 ++++++++++++++++++++-----------
 1 file changed, 24 insertions(+), 12 deletions(-)

diff --git a/arch/arm64/boot/dts/cix/sky1.dtsi b/arch/arm64/boot/dts/cix/sky1.dtsi
index 0a820f45feb9..cd498ee7e9a7 100644
--- a/arch/arm64/boot/dts/cix/sky1.dtsi
+++ b/arch/arm64/boot/dts/cix/sky1.dtsi
@@ -518,18 +518,30 @@ iomuxc: pinctrl@4170000 {
 			reg = <0x0 0x04170000 0x0 0x1000>;
 		};
 
-		fch_dmac: dma-controller@4190000 {
-			compatible = "arm,dma-350";
-			reg = <0x0 0x4190000 0x0 0x10000>;
-			interrupts = <GIC_SPI 303 IRQ_TYPE_LEVEL_HIGH 0>,
-				     <GIC_SPI 303 IRQ_TYPE_LEVEL_HIGH 0>,
-				     <GIC_SPI 303 IRQ_TYPE_LEVEL_HIGH 0>,
-				     <GIC_SPI 303 IRQ_TYPE_LEVEL_HIGH 0>,
-				     <GIC_SPI 303 IRQ_TYPE_LEVEL_HIGH 0>,
-				     <GIC_SPI 303 IRQ_TYPE_LEVEL_HIGH 0>,
-				     <GIC_SPI 303 IRQ_TYPE_LEVEL_HIGH 0>,
-				     <GIC_SPI 303 IRQ_TYPE_LEVEL_HIGH 0>;
-			#dma-cells = <1>;
+		fch-dma-bus {
+			compatible = "simple-bus";
+			ranges;
+			#address-cells = <2>;
+			dma-ranges = <0x0 0x040a0000 0x0 0x040b0000 0x0 0x00040000>,
+				     <0x0 0x80000000 0x0 0x80000000 0x8 0x00000000>,
+				     <0x80 0x00000000 0x80 0x00000000 0x80 0x00000000>;
+			#size-cells = <2>;
+
+			fch_dmac: dma-controller@4190000 {
+				compatible = "arm,dma-350";
+				reg = <0x0 0x04190000 0x0 0x10000>;
+				clocks = <&scmi_clk CLK_TREE_FCH_DMA_ACLK>;
+				#dma-cells = <1>;
+				interrupts =
+					<GIC_SPI 303 IRQ_TYPE_LEVEL_HIGH 0>,
+					<GIC_SPI 303 IRQ_TYPE_LEVEL_HIGH 0>,
+					<GIC_SPI 303 IRQ_TYPE_LEVEL_HIGH 0>,
+					<GIC_SPI 303 IRQ_TYPE_LEVEL_HIGH 0>,
+					<GIC_SPI 303 IRQ_TYPE_LEVEL_HIGH 0>,
+					<GIC_SPI 303 IRQ_TYPE_LEVEL_HIGH 0>,
+					<GIC_SPI 303 IRQ_TYPE_LEVEL_HIGH 0>,
+					<GIC_SPI 303 IRQ_TYPE_LEVEL_HIGH 0>;
+			};
 		};
 
 		mbox_ap2se: mailbox@5060000 {
-- 
2.54.0

Re: [PATCH v5 3/5] dt-bindings: dma: arm,dma-350: Document optional clocks and resets

[Frank Li]

On Wed, Nov 04, 2026 at 08:44:09PM +0800, Jelly Jia wrote:
> Some integrations gate the DMA-350 controller with a bus clock or hold it
> in reset. Sky1 provides a clock for both its FCH and AUDSS instances, and
> a reset for the AUDSS instance. Document these standard resources on the
> DMA controller node.
>
> Neither property is required, so existing device trees are unchanged.
>
> Signed-off-by: Jelly Jia <Jelly.Jia@cixtech.com>
> ---
>  .../devicetree/bindings/dma/arm,dma-350.yaml     | 16 +++++++++++++---
>  1 file changed, 13 insertions(+), 3 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/dma/arm,dma-350.yaml b/Documentation/devicetree/bindings/dma/arm,dma-350.yaml
> index 429f682f15d8..43279878207c 100644
> --- a/Documentation/devicetree/bindings/dma/arm,dma-350.yaml
> +++ b/Documentation/devicetree/bindings/dma/arm,dma-350.yaml
> @@ -9,9 +9,6 @@ title: Arm CoreLink DMA-350 Controller
>  maintainers:
>    - Robin Murphy <robin.murphy@arm.com>
>
> -allOf:
> -  - $ref: dma-controller.yaml#
> -
>  properties:
>    compatible:
>      const: arm,dma-350

Suppose you should add front compatible string and fall back to arm,dma-350

and use front compatible at if branch to restrict clocks and resets.

Frank

> @@ -36,9 +33,22 @@ properties:
>      const: 1
>      description: The cell is the trigger input number
>
> +  clocks:
> +    maxItems: 1
> +    description:
> +      Optional bus clock, where the integration gates the controller clock.
> +
> +  resets:
> +    maxItems: 1
> +    description:
> +      Optional reset line, where the integration exposes one.
> +
>  required:
>    - compatible
>    - reg
>    - interrupts
>
> +allOf:
> +  - $ref: dma-controller.yaml#
> +
>  unevaluatedProperties: false
> --
> 2.54.0
>

Re: [PATCH v5 4/5] dmaengine: arm-dma350: Support integration clocks and resets

[Frank Li]

On Wed, Nov 04, 2026 at 08:44:10PM +0800, Jelly Jia wrote:
> DMA-350 integrations may gate the controller with a clock or hold it in
> reset. Enable an optional clock and deassert an optional reset before
> accessing the controller registers.
>
> Use the deasserted reset helper rather than requesting a reset pulse.
> This also supports reset controllers that only implement assert and
> deassert operations.
>
> Both resources remain optional, so existing integrations without them
> are unchanged.
>
> Signed-off-by: Jelly Jia <Jelly.Jia@cixtech.com>
> ---

Reviewed-by: Frank Li <Frank.Li@nxp.com>

>  drivers/dma/arm-dma350.c | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
>
> diff --git a/drivers/dma/arm-dma350.c b/drivers/dma/arm-dma350.c
> index cfe3bacfab68..2f22f8a0ab47 100644
> --- a/drivers/dma/arm-dma350.c
> +++ b/drivers/dma/arm-dma350.c
> @@ -4,6 +4,7 @@
>
>  #include <linux/bitfield.h>
>  #include <linux/bitops.h>
> +#include <linux/clk.h>
>  #include <linux/dmaengine.h>
>  #include <linux/dma-mapping.h>
>  #include <linux/dmapool.h>
> @@ -14,6 +15,7 @@
>  #include <linux/module.h>
>  #include <linux/overflow.h>
>  #include <linux/platform_device.h>
> +#include <linux/reset.h>
>  #include <linux/scatterlist.h>
>  #include <linux/slab.h>
>
> @@ -1247,12 +1249,24 @@ static void d350_free_chan_resources(struct dma_chan *chan)
>  static int d350_probe(struct platform_device *pdev)
>  {
>  	struct device *dev = &pdev->dev;
> +	struct reset_control *reset;
> +	struct clk *clk;
>  	struct d350 *dmac;
>  	void __iomem *base;
>  	u32 reg;
>  	int ret, nchan, dw, aw, r, p;
>  	bool coherent, memset;
>
> +	clk = devm_clk_get_optional_enabled(dev, NULL);
> +	if (IS_ERR(clk))
> +		return dev_err_probe(dev, PTR_ERR(clk),
> +				     "failed to enable clock\n");
> +
> +	reset = devm_reset_control_get_optional_exclusive_deasserted(dev, NULL);
> +	if (IS_ERR(reset))
> +		return dev_err_probe(dev, PTR_ERR(reset),
> +				     "failed to deassert reset\n");
> +
>  	base = devm_platform_ioremap_resource(pdev, 0);
>  	if (IS_ERR(base))
>  		return PTR_ERR(base);
> --
> 2.54.0
>