]> git.ipfire.org Git - thirdparty/kernel/stable.git/commitdiff
dmaengine: mmp_pdma: Add operations structure for controller abstraction
authorGuodong Xu <guodong@riscstar.com>
Fri, 22 Aug 2025 03:06:30 +0000 (11:06 +0800)
committerVinod Koul <vkoul@kernel.org>
Tue, 2 Sep 2025 07:07:42 +0000 (12:37 +0530)
Introduce mmp_pdma_ops structure to abstract 32-bit addressing operations
and enable support for different controller variants. This prepares for
adding 64-bit addressing support.

The ops structure includes:
- Hardware register operations (read/write DDADR, DSADR, DTADR)
- Descriptor memory operations (manipulate descriptor structs)
- Controller configuration (run bits, DMA mask)

Convert existing 32-bit operations to use the new abstraction layer
while maintaining backward compatibility.

Cc: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Guodong Xu <guodong@riscstar.com>
Link: https://lore.kernel.org/r/20250822-working_dma_0701_v2-v5-4-f5c0eda734cc@riscstar.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
drivers/dma/mmp_pdma.c

index fe627efeaff07436647f86ab5ec5333144a3c92d..38d1a4cdfd0e92e53c77b61caa1133559ef40dbd 100644 (file)
@@ -25,7 +25,7 @@
 #define DCSR           0x0000
 #define DALGN          0x00a0
 #define DINT           0x00f0
-#define DDADR          0x0200
+#define DDADR(n)       (0x0200 + ((n) << 4))
 #define DSADR(n)       (0x0204 + ((n) << 4))
 #define DTADR(n)       (0x0208 + ((n) << 4))
 #define DCMD           0x020c
@@ -120,12 +120,55 @@ struct mmp_pdma_phy {
        struct mmp_pdma_chan *vchan;
 };
 
+/**
+ * struct mmp_pdma_ops - Operations for the MMP PDMA controller
+ *
+ * Hardware Register Operations (read/write hardware registers):
+ * @write_next_addr: Function to program address of next descriptor into
+ *                   DDADR/DDADRH
+ * @read_src_addr: Function to read the source address from DSADR/DSADRH
+ * @read_dst_addr: Function to read the destination address from DTADR/DTADRH
+ *
+ * Descriptor Memory Operations (manipulate descriptor structs in memory):
+ * @set_desc_next_addr: Function to set next descriptor address in descriptor
+ * @set_desc_src_addr: Function to set the source address in descriptor
+ * @set_desc_dst_addr: Function to set the destination address in descriptor
+ * @get_desc_src_addr: Function to get the source address from descriptor
+ * @get_desc_dst_addr: Function to get the destination address from descriptor
+ *
+ * Controller Configuration:
+ * @run_bits:   Control bits in DCSR register for channel start/stop
+ * @dma_mask:   DMA addressing capability of controller. 0 to use OF/platform
+ *              settings, or explicit mask like DMA_BIT_MASK(32/64)
+ */
+struct mmp_pdma_ops {
+       /* Hardware Register Operations */
+       void (*write_next_addr)(struct mmp_pdma_phy *phy, dma_addr_t addr);
+       u64 (*read_src_addr)(struct mmp_pdma_phy *phy);
+       u64 (*read_dst_addr)(struct mmp_pdma_phy *phy);
+
+       /* Descriptor Memory Operations */
+       void (*set_desc_next_addr)(struct mmp_pdma_desc_hw *desc,
+                                  dma_addr_t addr);
+       void (*set_desc_src_addr)(struct mmp_pdma_desc_hw *desc,
+                                 dma_addr_t addr);
+       void (*set_desc_dst_addr)(struct mmp_pdma_desc_hw *desc,
+                                 dma_addr_t addr);
+       u64 (*get_desc_src_addr)(const struct mmp_pdma_desc_hw *desc);
+       u64 (*get_desc_dst_addr)(const struct mmp_pdma_desc_hw *desc);
+
+       /* Controller Configuration */
+       u32 run_bits;
+       u64 dma_mask;
+};
+
 struct mmp_pdma_device {
        int                             dma_channels;
        void __iomem                    *base;
        struct device                   *dev;
        struct dma_device               device;
        struct mmp_pdma_phy             *phy;
+       const struct mmp_pdma_ops       *ops;
        spinlock_t phy_lock; /* protect alloc/free phy channels */
 };
 
@@ -138,24 +181,61 @@ struct mmp_pdma_device {
 #define to_mmp_pdma_dev(dmadev)                                        \
        container_of(dmadev, struct mmp_pdma_device, device)
 
-static int mmp_pdma_config_write(struct dma_chan *dchan,
-                          struct dma_slave_config *cfg,
-                          enum dma_transfer_direction direction);
+/* For 32-bit PDMA */
+static void write_next_addr_32(struct mmp_pdma_phy *phy, dma_addr_t addr)
+{
+       writel(addr, phy->base + DDADR(phy->idx));
+}
+
+static u64 read_src_addr_32(struct mmp_pdma_phy *phy)
+{
+       return readl(phy->base + DSADR(phy->idx));
+}
+
+static u64 read_dst_addr_32(struct mmp_pdma_phy *phy)
+{
+       return readl(phy->base + DTADR(phy->idx));
+}
+
+static void set_desc_next_addr_32(struct mmp_pdma_desc_hw *desc, dma_addr_t addr)
+{
+       desc->ddadr = addr;
+}
+
+static void set_desc_src_addr_32(struct mmp_pdma_desc_hw *desc, dma_addr_t addr)
+{
+       desc->dsadr = addr;
+}
 
-static void set_desc(struct mmp_pdma_phy *phy, dma_addr_t addr)
+static void set_desc_dst_addr_32(struct mmp_pdma_desc_hw *desc, dma_addr_t addr)
 {
-       u32 reg = (phy->idx << 4) + DDADR;
+       desc->dtadr = addr;
+}
 
-       writel(addr, phy->base + reg);
+static u64 get_desc_src_addr_32(const struct mmp_pdma_desc_hw *desc)
+{
+       return desc->dsadr;
 }
 
+static u64 get_desc_dst_addr_32(const struct mmp_pdma_desc_hw *desc)
+{
+       return desc->dtadr;
+}
+
+static int mmp_pdma_config_write(struct dma_chan *dchan,
+                                struct dma_slave_config *cfg,
+                                enum dma_transfer_direction direction);
+
 static void enable_chan(struct mmp_pdma_phy *phy)
 {
        u32 reg, dalgn;
+       struct mmp_pdma_device *pdev;
 
        if (!phy->vchan)
                return;
 
+       pdev = to_mmp_pdma_dev(phy->vchan->chan.device);
+
        reg = DRCMR(phy->vchan->drcmr);
        writel(DRCMR_MAPVLD | phy->idx, phy->base + reg);
 
@@ -167,18 +247,29 @@ static void enable_chan(struct mmp_pdma_phy *phy)
        writel(dalgn, phy->base + DALGN);
 
        reg = (phy->idx << 2) + DCSR;
-       writel(readl(phy->base + reg) | DCSR_RUN, phy->base + reg);
+       writel(readl(phy->base + reg) | pdev->ops->run_bits,
+              phy->base + reg);
 }
 
 static void disable_chan(struct mmp_pdma_phy *phy)
 {
-       u32 reg;
+       u32 reg, dcsr;
 
        if (!phy)
                return;
 
        reg = (phy->idx << 2) + DCSR;
-       writel(readl(phy->base + reg) & ~DCSR_RUN, phy->base + reg);
+       dcsr = readl(phy->base + reg);
+
+       if (phy->vchan) {
+               struct mmp_pdma_device *pdev;
+
+               pdev = to_mmp_pdma_dev(phy->vchan->chan.device);
+               writel(dcsr & ~pdev->ops->run_bits, phy->base + reg);
+       } else {
+               /* If no vchan, just clear the RUN bit */
+               writel(dcsr & ~DCSR_RUN, phy->base + reg);
+       }
 }
 
 static int clear_chan_irq(struct mmp_pdma_phy *phy)
@@ -297,6 +388,7 @@ static void mmp_pdma_free_phy(struct mmp_pdma_chan *pchan)
 static void start_pending_queue(struct mmp_pdma_chan *chan)
 {
        struct mmp_pdma_desc_sw *desc;
+       struct mmp_pdma_device *pdev = to_mmp_pdma_dev(chan->chan.device);
 
        /* still in running, irq will start the pending list */
        if (!chan->idle) {
@@ -331,7 +423,7 @@ static void start_pending_queue(struct mmp_pdma_chan *chan)
         * Program the descriptor's address into the DMA controller,
         * then start the DMA transaction
         */
-       set_desc(chan->phy, desc->async_tx.phys);
+       pdev->ops->write_next_addr(chan->phy, desc->async_tx.phys);
        enable_chan(chan->phy);
        chan->idle = false;
 }
@@ -447,15 +539,14 @@ mmp_pdma_prep_memcpy(struct dma_chan *dchan,
                     size_t len, unsigned long flags)
 {
        struct mmp_pdma_chan *chan;
+       struct mmp_pdma_device *pdev;
        struct mmp_pdma_desc_sw *first = NULL, *prev = NULL, *new;
        size_t copy = 0;
 
-       if (!dchan)
-               return NULL;
-
-       if (!len)
+       if (!dchan || !len)
                return NULL;
 
+       pdev = to_mmp_pdma_dev(dchan->device);
        chan = to_mmp_pdma_chan(dchan);
        chan->byte_align = false;
 
@@ -478,13 +569,14 @@ mmp_pdma_prep_memcpy(struct dma_chan *dchan,
                        chan->byte_align = true;
 
                new->desc.dcmd = chan->dcmd | (DCMD_LENGTH & copy);
-               new->desc.dsadr = dma_src;
-               new->desc.dtadr = dma_dst;
+               pdev->ops->set_desc_src_addr(&new->desc, dma_src);
+               pdev->ops->set_desc_dst_addr(&new->desc, dma_dst);
 
                if (!first)
                        first = new;
                else
-                       prev->desc.ddadr = new->async_tx.phys;
+                       pdev->ops->set_desc_next_addr(&prev->desc,
+                                                     new->async_tx.phys);
 
                new->async_tx.cookie = 0;
                async_tx_ack(&new->async_tx);
@@ -528,6 +620,7 @@ mmp_pdma_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
                       unsigned long flags, void *context)
 {
        struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
+       struct mmp_pdma_device *pdev = to_mmp_pdma_dev(dchan->device);
        struct mmp_pdma_desc_sw *first = NULL, *prev = NULL, *new = NULL;
        size_t len, avail;
        struct scatterlist *sg;
@@ -559,17 +652,18 @@ mmp_pdma_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
 
                        new->desc.dcmd = chan->dcmd | (DCMD_LENGTH & len);
                        if (dir == DMA_MEM_TO_DEV) {
-                               new->desc.dsadr = addr;
+                               pdev->ops->set_desc_src_addr(&new->desc, addr);
                                new->desc.dtadr = chan->dev_addr;
                        } else {
                                new->desc.dsadr = chan->dev_addr;
-                               new->desc.dtadr = addr;
+                               pdev->ops->set_desc_dst_addr(&new->desc, addr);
                        }
 
                        if (!first)
                                first = new;
                        else
-                               prev->desc.ddadr = new->async_tx.phys;
+                               pdev->ops->set_desc_next_addr(&prev->desc,
+                                                          new->async_tx.phys);
 
                        new->async_tx.cookie = 0;
                        async_tx_ack(&new->async_tx);
@@ -609,12 +703,15 @@ mmp_pdma_prep_dma_cyclic(struct dma_chan *dchan,
                         unsigned long flags)
 {
        struct mmp_pdma_chan *chan;
+       struct mmp_pdma_device *pdev;
        struct mmp_pdma_desc_sw *first = NULL, *prev = NULL, *new;
        dma_addr_t dma_src, dma_dst;
 
        if (!dchan || !len || !period_len)
                return NULL;
 
+       pdev = to_mmp_pdma_dev(dchan->device);
+
        /* the buffer length must be a multiple of period_len */
        if (len % period_len != 0)
                return NULL;
@@ -651,13 +748,14 @@ mmp_pdma_prep_dma_cyclic(struct dma_chan *dchan,
 
                new->desc.dcmd = (chan->dcmd | DCMD_ENDIRQEN |
                                  (DCMD_LENGTH & period_len));
-               new->desc.dsadr = dma_src;
-               new->desc.dtadr = dma_dst;
+               pdev->ops->set_desc_src_addr(&new->desc, dma_src);
+               pdev->ops->set_desc_dst_addr(&new->desc, dma_dst);
 
                if (!first)
                        first = new;
                else
-                       prev->desc.ddadr = new->async_tx.phys;
+                       pdev->ops->set_desc_next_addr(&prev->desc,
+                                                     new->async_tx.phys);
 
                new->async_tx.cookie = 0;
                async_tx_ack(&new->async_tx);
@@ -678,7 +776,7 @@ mmp_pdma_prep_dma_cyclic(struct dma_chan *dchan,
        first->async_tx.cookie = -EBUSY;
 
        /* make the cyclic link */
-       new->desc.ddadr = first->async_tx.phys;
+       pdev->ops->set_desc_next_addr(&new->desc, first->async_tx.phys);
        chan->cyclic_first = first;
 
        return &first->async_tx;
@@ -764,7 +862,9 @@ static unsigned int mmp_pdma_residue(struct mmp_pdma_chan *chan,
                                     dma_cookie_t cookie)
 {
        struct mmp_pdma_desc_sw *sw;
-       u32 curr, residue = 0;
+       struct mmp_pdma_device *pdev = to_mmp_pdma_dev(chan->chan.device);
+       u64 curr;
+       u32 residue = 0;
        bool passed = false;
        bool cyclic = chan->cyclic_first != NULL;
 
@@ -776,17 +876,18 @@ static unsigned int mmp_pdma_residue(struct mmp_pdma_chan *chan,
                return 0;
 
        if (chan->dir == DMA_DEV_TO_MEM)
-               curr = readl(chan->phy->base + DTADR(chan->phy->idx));
+               curr = pdev->ops->read_dst_addr(chan->phy);
        else
-               curr = readl(chan->phy->base + DSADR(chan->phy->idx));
+               curr = pdev->ops->read_src_addr(chan->phy);
 
        list_for_each_entry(sw, &chan->chain_running, node) {
-               u32 start, end, len;
+               u64 start, end;
+               u32 len;
 
                if (chan->dir == DMA_DEV_TO_MEM)
-                       start = sw->desc.dtadr;
+                       start = pdev->ops->get_desc_dst_addr(&sw->desc);
                else
-                       start = sw->desc.dsadr;
+                       start = pdev->ops->get_desc_src_addr(&sw->desc);
 
                len = sw->desc.dcmd & DCMD_LENGTH;
                end = start + len;
@@ -802,7 +903,7 @@ static unsigned int mmp_pdma_residue(struct mmp_pdma_chan *chan,
                if (passed) {
                        residue += len;
                } else if (curr >= start && curr <= end) {
-                       residue += end - curr;
+                       residue += (u32)(end - curr);
                        passed = true;
                }
 
@@ -996,9 +1097,26 @@ static int mmp_pdma_chan_init(struct mmp_pdma_device *pdev, int idx, int irq)
        return 0;
 }
 
+static const struct mmp_pdma_ops marvell_pdma_v1_ops = {
+       .write_next_addr = write_next_addr_32,
+       .read_src_addr = read_src_addr_32,
+       .read_dst_addr = read_dst_addr_32,
+       .set_desc_next_addr = set_desc_next_addr_32,
+       .set_desc_src_addr = set_desc_src_addr_32,
+       .set_desc_dst_addr = set_desc_dst_addr_32,
+       .get_desc_src_addr = get_desc_src_addr_32,
+       .get_desc_dst_addr = get_desc_dst_addr_32,
+       .run_bits = (DCSR_RUN),
+       .dma_mask = 0,                  /* let OF/platform set DMA mask */
+};
+
 static const struct of_device_id mmp_pdma_dt_ids[] = {
-       { .compatible = "marvell,pdma-1.0", },
-       {}
+       {
+               .compatible = "marvell,pdma-1.0",
+               .data = &marvell_pdma_v1_ops
+       }, {
+               /* sentinel */
+       }
 };
 MODULE_DEVICE_TABLE(of, mmp_pdma_dt_ids);
 
@@ -1050,6 +1168,10 @@ static int mmp_pdma_probe(struct platform_device *op)
        if (IS_ERR(rst))
                return PTR_ERR(rst);
 
+       pdev->ops = of_device_get_match_data(&op->dev);
+       if (!pdev->ops)
+               return -ENODEV;
+
        if (pdev->dev->of_node) {
                /* Parse new and deprecated dma-channels properties */
                if (of_property_read_u32(pdev->dev->of_node, "dma-channels",
@@ -1111,7 +1233,10 @@ static int mmp_pdma_probe(struct platform_device *op)
        pdev->device.directions = BIT(DMA_MEM_TO_DEV) | BIT(DMA_DEV_TO_MEM);
        pdev->device.residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
 
-       if (pdev->dev->coherent_dma_mask)
+       /* Set DMA mask based on ops->dma_mask, or OF/platform */
+       if (pdev->ops->dma_mask)
+               dma_set_mask(pdev->dev, pdev->ops->dma_mask);
+       else if (pdev->dev->coherent_dma_mask)
                dma_set_mask(pdev->dev, pdev->dev->coherent_dma_mask);
        else
                dma_set_mask(pdev->dev, DMA_BIT_MASK(64));