summaryrefslogtreecommitdiff
path: root/drivers/dma/mmp_pdma.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/dma/mmp_pdma.c')
-rw-r--r--drivers/dma/mmp_pdma.c1138
1 files changed, 1138 insertions, 0 deletions
diff --git a/drivers/dma/mmp_pdma.c b/drivers/dma/mmp_pdma.c
new file mode 100644
index 000000000..462a0229a
--- /dev/null
+++ b/drivers/dma/mmp_pdma.c
@@ -0,0 +1,1138 @@
+/*
+ * Copyright 2012 Marvell International Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/interrupt.h>
+#include <linux/dma-mapping.h>
+#include <linux/slab.h>
+#include <linux/dmaengine.h>
+#include <linux/platform_device.h>
+#include <linux/device.h>
+#include <linux/platform_data/mmp_dma.h>
+#include <linux/dmapool.h>
+#include <linux/of_device.h>
+#include <linux/of_dma.h>
+#include <linux/of.h>
+#include <linux/dma/mmp-pdma.h>
+
+#include "dmaengine.h"
+
+#define DCSR 0x0000
+#define DALGN 0x00a0
+#define DINT 0x00f0
+#define DDADR 0x0200
+#define DSADR(n) (0x0204 + ((n) << 4))
+#define DTADR(n) (0x0208 + ((n) << 4))
+#define DCMD 0x020c
+
+#define DCSR_RUN BIT(31) /* Run Bit (read / write) */
+#define DCSR_NODESC BIT(30) /* No-Descriptor Fetch (read / write) */
+#define DCSR_STOPIRQEN BIT(29) /* Stop Interrupt Enable (read / write) */
+#define DCSR_REQPEND BIT(8) /* Request Pending (read-only) */
+#define DCSR_STOPSTATE BIT(3) /* Stop State (read-only) */
+#define DCSR_ENDINTR BIT(2) /* End Interrupt (read / write) */
+#define DCSR_STARTINTR BIT(1) /* Start Interrupt (read / write) */
+#define DCSR_BUSERR BIT(0) /* Bus Error Interrupt (read / write) */
+
+#define DCSR_EORIRQEN BIT(28) /* End of Receive Interrupt Enable (R/W) */
+#define DCSR_EORJMPEN BIT(27) /* Jump to next descriptor on EOR */
+#define DCSR_EORSTOPEN BIT(26) /* STOP on an EOR */
+#define DCSR_SETCMPST BIT(25) /* Set Descriptor Compare Status */
+#define DCSR_CLRCMPST BIT(24) /* Clear Descriptor Compare Status */
+#define DCSR_CMPST BIT(10) /* The Descriptor Compare Status */
+#define DCSR_EORINTR BIT(9) /* The end of Receive */
+
+#define DRCMR(n) ((((n) < 64) ? 0x0100 : 0x1100) + (((n) & 0x3f) << 2))
+#define DRCMR_MAPVLD BIT(7) /* Map Valid (read / write) */
+#define DRCMR_CHLNUM 0x1f /* mask for Channel Number (read / write) */
+
+#define DDADR_DESCADDR 0xfffffff0 /* Address of next descriptor (mask) */
+#define DDADR_STOP BIT(0) /* Stop (read / write) */
+
+#define DCMD_INCSRCADDR BIT(31) /* Source Address Increment Setting. */
+#define DCMD_INCTRGADDR BIT(30) /* Target Address Increment Setting. */
+#define DCMD_FLOWSRC BIT(29) /* Flow Control by the source. */
+#define DCMD_FLOWTRG BIT(28) /* Flow Control by the target. */
+#define DCMD_STARTIRQEN BIT(22) /* Start Interrupt Enable */
+#define DCMD_ENDIRQEN BIT(21) /* End Interrupt Enable */
+#define DCMD_ENDIAN BIT(18) /* Device Endian-ness. */
+#define DCMD_BURST8 (1 << 16) /* 8 byte burst */
+#define DCMD_BURST16 (2 << 16) /* 16 byte burst */
+#define DCMD_BURST32 (3 << 16) /* 32 byte burst */
+#define DCMD_WIDTH1 (1 << 14) /* 1 byte width */
+#define DCMD_WIDTH2 (2 << 14) /* 2 byte width (HalfWord) */
+#define DCMD_WIDTH4 (3 << 14) /* 4 byte width (Word) */
+#define DCMD_LENGTH 0x01fff /* length mask (max = 8K - 1) */
+
+#define PDMA_ALIGNMENT 3
+#define PDMA_MAX_DESC_BYTES DCMD_LENGTH
+
+struct mmp_pdma_desc_hw {
+ u32 ddadr; /* Points to the next descriptor + flags */
+ u32 dsadr; /* DSADR value for the current transfer */
+ u32 dtadr; /* DTADR value for the current transfer */
+ u32 dcmd; /* DCMD value for the current transfer */
+} __aligned(32);
+
+struct mmp_pdma_desc_sw {
+ struct mmp_pdma_desc_hw desc;
+ struct list_head node;
+ struct list_head tx_list;
+ struct dma_async_tx_descriptor async_tx;
+};
+
+struct mmp_pdma_phy;
+
+struct mmp_pdma_chan {
+ struct device *dev;
+ struct dma_chan chan;
+ struct dma_async_tx_descriptor desc;
+ struct mmp_pdma_phy *phy;
+ enum dma_transfer_direction dir;
+
+ struct mmp_pdma_desc_sw *cyclic_first; /* first desc_sw if channel
+ * is in cyclic mode */
+
+ /* channel's basic info */
+ struct tasklet_struct tasklet;
+ u32 dcmd;
+ u32 drcmr;
+ u32 dev_addr;
+
+ /* list for desc */
+ spinlock_t desc_lock; /* Descriptor list lock */
+ struct list_head chain_pending; /* Link descriptors queue for pending */
+ struct list_head chain_running; /* Link descriptors queue for running */
+ bool idle; /* channel statue machine */
+ bool byte_align;
+
+ struct dma_pool *desc_pool; /* Descriptors pool */
+};
+
+struct mmp_pdma_phy {
+ int idx;
+ void __iomem *base;
+ struct mmp_pdma_chan *vchan;
+};
+
+struct mmp_pdma_device {
+ int dma_channels;
+ void __iomem *base;
+ struct device *dev;
+ struct dma_device device;
+ struct mmp_pdma_phy *phy;
+ spinlock_t phy_lock; /* protect alloc/free phy channels */
+};
+
+#define tx_to_mmp_pdma_desc(tx) \
+ container_of(tx, struct mmp_pdma_desc_sw, async_tx)
+#define to_mmp_pdma_desc(lh) \
+ container_of(lh, struct mmp_pdma_desc_sw, node)
+#define to_mmp_pdma_chan(dchan) \
+ container_of(dchan, struct mmp_pdma_chan, chan)
+#define to_mmp_pdma_dev(dmadev) \
+ container_of(dmadev, struct mmp_pdma_device, device)
+
+static void set_desc(struct mmp_pdma_phy *phy, dma_addr_t addr)
+{
+ u32 reg = (phy->idx << 4) + DDADR;
+
+ writel(addr, phy->base + reg);
+}
+
+static void enable_chan(struct mmp_pdma_phy *phy)
+{
+ u32 reg, dalgn;
+
+ if (!phy->vchan)
+ return;
+
+ reg = DRCMR(phy->vchan->drcmr);
+ writel(DRCMR_MAPVLD | phy->idx, phy->base + reg);
+
+ dalgn = readl(phy->base + DALGN);
+ if (phy->vchan->byte_align)
+ dalgn |= 1 << phy->idx;
+ else
+ dalgn &= ~(1 << phy->idx);
+ writel(dalgn, phy->base + DALGN);
+
+ reg = (phy->idx << 2) + DCSR;
+ writel(readl(phy->base + reg) | DCSR_RUN, phy->base + reg);
+}
+
+static void disable_chan(struct mmp_pdma_phy *phy)
+{
+ u32 reg;
+
+ if (!phy)
+ return;
+
+ reg = (phy->idx << 2) + DCSR;
+ writel(readl(phy->base + reg) & ~DCSR_RUN, phy->base + reg);
+}
+
+static int clear_chan_irq(struct mmp_pdma_phy *phy)
+{
+ u32 dcsr;
+ u32 dint = readl(phy->base + DINT);
+ u32 reg = (phy->idx << 2) + DCSR;
+
+ if (!(dint & BIT(phy->idx)))
+ return -EAGAIN;
+
+ /* clear irq */
+ dcsr = readl(phy->base + reg);
+ writel(dcsr, phy->base + reg);
+ if ((dcsr & DCSR_BUSERR) && (phy->vchan))
+ dev_warn(phy->vchan->dev, "DCSR_BUSERR\n");
+
+ return 0;
+}
+
+static irqreturn_t mmp_pdma_chan_handler(int irq, void *dev_id)
+{
+ struct mmp_pdma_phy *phy = dev_id;
+
+ if (clear_chan_irq(phy) != 0)
+ return IRQ_NONE;
+
+ tasklet_schedule(&phy->vchan->tasklet);
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t mmp_pdma_int_handler(int irq, void *dev_id)
+{
+ struct mmp_pdma_device *pdev = dev_id;
+ struct mmp_pdma_phy *phy;
+ u32 dint = readl(pdev->base + DINT);
+ int i, ret;
+ int irq_num = 0;
+
+ while (dint) {
+ i = __ffs(dint);
+ /* only handle interrupts belonging to pdma driver*/
+ if (i >= pdev->dma_channels)
+ break;
+ dint &= (dint - 1);
+ phy = &pdev->phy[i];
+ ret = mmp_pdma_chan_handler(irq, phy);
+ if (ret == IRQ_HANDLED)
+ irq_num++;
+ }
+
+ if (irq_num)
+ return IRQ_HANDLED;
+
+ return IRQ_NONE;
+}
+
+/* lookup free phy channel as descending priority */
+static struct mmp_pdma_phy *lookup_phy(struct mmp_pdma_chan *pchan)
+{
+ int prio, i;
+ struct mmp_pdma_device *pdev = to_mmp_pdma_dev(pchan->chan.device);
+ struct mmp_pdma_phy *phy, *found = NULL;
+ unsigned long flags;
+
+ /*
+ * dma channel priorities
+ * ch 0 - 3, 16 - 19 <--> (0)
+ * ch 4 - 7, 20 - 23 <--> (1)
+ * ch 8 - 11, 24 - 27 <--> (2)
+ * ch 12 - 15, 28 - 31 <--> (3)
+ */
+
+ spin_lock_irqsave(&pdev->phy_lock, flags);
+ for (prio = 0; prio <= ((pdev->dma_channels - 1) & 0xf) >> 2; prio++) {
+ for (i = 0; i < pdev->dma_channels; i++) {
+ if (prio != (i & 0xf) >> 2)
+ continue;
+ phy = &pdev->phy[i];
+ if (!phy->vchan) {
+ phy->vchan = pchan;
+ found = phy;
+ goto out_unlock;
+ }
+ }
+ }
+
+out_unlock:
+ spin_unlock_irqrestore(&pdev->phy_lock, flags);
+ return found;
+}
+
+static void mmp_pdma_free_phy(struct mmp_pdma_chan *pchan)
+{
+ struct mmp_pdma_device *pdev = to_mmp_pdma_dev(pchan->chan.device);
+ unsigned long flags;
+ u32 reg;
+
+ if (!pchan->phy)
+ return;
+
+ /* clear the channel mapping in DRCMR */
+ reg = DRCMR(pchan->drcmr);
+ writel(0, pchan->phy->base + reg);
+
+ spin_lock_irqsave(&pdev->phy_lock, flags);
+ pchan->phy->vchan = NULL;
+ pchan->phy = NULL;
+ spin_unlock_irqrestore(&pdev->phy_lock, flags);
+}
+
+/**
+ * start_pending_queue - transfer any pending transactions
+ * pending list ==> running list
+ */
+static void start_pending_queue(struct mmp_pdma_chan *chan)
+{
+ struct mmp_pdma_desc_sw *desc;
+
+ /* still in running, irq will start the pending list */
+ if (!chan->idle) {
+ dev_dbg(chan->dev, "DMA controller still busy\n");
+ return;
+ }
+
+ if (list_empty(&chan->chain_pending)) {
+ /* chance to re-fetch phy channel with higher prio */
+ mmp_pdma_free_phy(chan);
+ dev_dbg(chan->dev, "no pending list\n");
+ return;
+ }
+
+ if (!chan->phy) {
+ chan->phy = lookup_phy(chan);
+ if (!chan->phy) {
+ dev_dbg(chan->dev, "no free dma channel\n");
+ return;
+ }
+ }
+
+ /*
+ * pending -> running
+ * reintilize pending list
+ */
+ desc = list_first_entry(&chan->chain_pending,
+ struct mmp_pdma_desc_sw, node);
+ list_splice_tail_init(&chan->chain_pending, &chan->chain_running);
+
+ /*
+ * Program the descriptor's address into the DMA controller,
+ * then start the DMA transaction
+ */
+ set_desc(chan->phy, desc->async_tx.phys);
+ enable_chan(chan->phy);
+ chan->idle = false;
+}
+
+
+/* desc->tx_list ==> pending list */
+static dma_cookie_t mmp_pdma_tx_submit(struct dma_async_tx_descriptor *tx)
+{
+ struct mmp_pdma_chan *chan = to_mmp_pdma_chan(tx->chan);
+ struct mmp_pdma_desc_sw *desc = tx_to_mmp_pdma_desc(tx);
+ struct mmp_pdma_desc_sw *child;
+ unsigned long flags;
+ dma_cookie_t cookie = -EBUSY;
+
+ spin_lock_irqsave(&chan->desc_lock, flags);
+
+ list_for_each_entry(child, &desc->tx_list, node) {
+ cookie = dma_cookie_assign(&child->async_tx);
+ }
+
+ /* softly link to pending list - desc->tx_list ==> pending list */
+ list_splice_tail_init(&desc->tx_list, &chan->chain_pending);
+
+ spin_unlock_irqrestore(&chan->desc_lock, flags);
+
+ return cookie;
+}
+
+static struct mmp_pdma_desc_sw *
+mmp_pdma_alloc_descriptor(struct mmp_pdma_chan *chan)
+{
+ struct mmp_pdma_desc_sw *desc;
+ dma_addr_t pdesc;
+
+ desc = dma_pool_alloc(chan->desc_pool, GFP_ATOMIC, &pdesc);
+ if (!desc) {
+ dev_err(chan->dev, "out of memory for link descriptor\n");
+ return NULL;
+ }
+
+ memset(desc, 0, sizeof(*desc));
+ INIT_LIST_HEAD(&desc->tx_list);
+ dma_async_tx_descriptor_init(&desc->async_tx, &chan->chan);
+ /* each desc has submit */
+ desc->async_tx.tx_submit = mmp_pdma_tx_submit;
+ desc->async_tx.phys = pdesc;
+
+ return desc;
+}
+
+/**
+ * mmp_pdma_alloc_chan_resources - Allocate resources for DMA channel.
+ *
+ * This function will create a dma pool for descriptor allocation.
+ * Request irq only when channel is requested
+ * Return - The number of allocated descriptors.
+ */
+
+static int mmp_pdma_alloc_chan_resources(struct dma_chan *dchan)
+{
+ struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
+
+ if (chan->desc_pool)
+ return 1;
+
+ chan->desc_pool = dma_pool_create(dev_name(&dchan->dev->device),
+ chan->dev,
+ sizeof(struct mmp_pdma_desc_sw),
+ __alignof__(struct mmp_pdma_desc_sw),
+ 0);
+ if (!chan->desc_pool) {
+ dev_err(chan->dev, "unable to allocate descriptor pool\n");
+ return -ENOMEM;
+ }
+
+ mmp_pdma_free_phy(chan);
+ chan->idle = true;
+ chan->dev_addr = 0;
+ return 1;
+}
+
+static void mmp_pdma_free_desc_list(struct mmp_pdma_chan *chan,
+ struct list_head *list)
+{
+ struct mmp_pdma_desc_sw *desc, *_desc;
+
+ list_for_each_entry_safe(desc, _desc, list, node) {
+ list_del(&desc->node);
+ dma_pool_free(chan->desc_pool, desc, desc->async_tx.phys);
+ }
+}
+
+static void mmp_pdma_free_chan_resources(struct dma_chan *dchan)
+{
+ struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
+ unsigned long flags;
+
+ spin_lock_irqsave(&chan->desc_lock, flags);
+ mmp_pdma_free_desc_list(chan, &chan->chain_pending);
+ mmp_pdma_free_desc_list(chan, &chan->chain_running);
+ spin_unlock_irqrestore(&chan->desc_lock, flags);
+
+ dma_pool_destroy(chan->desc_pool);
+ chan->desc_pool = NULL;
+ chan->idle = true;
+ chan->dev_addr = 0;
+ mmp_pdma_free_phy(chan);
+ return;
+}
+
+static struct dma_async_tx_descriptor *
+mmp_pdma_prep_memcpy(struct dma_chan *dchan,
+ dma_addr_t dma_dst, dma_addr_t dma_src,
+ size_t len, unsigned long flags)
+{
+ struct mmp_pdma_chan *chan;
+ struct mmp_pdma_desc_sw *first = NULL, *prev = NULL, *new;
+ size_t copy = 0;
+
+ if (!dchan)
+ return NULL;
+
+ if (!len)
+ return NULL;
+
+ chan = to_mmp_pdma_chan(dchan);
+ chan->byte_align = false;
+
+ if (!chan->dir) {
+ chan->dir = DMA_MEM_TO_MEM;
+ chan->dcmd = DCMD_INCTRGADDR | DCMD_INCSRCADDR;
+ chan->dcmd |= DCMD_BURST32;
+ }
+
+ do {
+ /* Allocate the link descriptor from DMA pool */
+ new = mmp_pdma_alloc_descriptor(chan);
+ if (!new) {
+ dev_err(chan->dev, "no memory for desc\n");
+ goto fail;
+ }
+
+ copy = min_t(size_t, len, PDMA_MAX_DESC_BYTES);
+ if (dma_src & 0x7 || dma_dst & 0x7)
+ chan->byte_align = true;
+
+ new->desc.dcmd = chan->dcmd | (DCMD_LENGTH & copy);
+ new->desc.dsadr = dma_src;
+ new->desc.dtadr = dma_dst;
+
+ if (!first)
+ first = new;
+ else
+ prev->desc.ddadr = new->async_tx.phys;
+
+ new->async_tx.cookie = 0;
+ async_tx_ack(&new->async_tx);
+
+ prev = new;
+ len -= copy;
+
+ if (chan->dir == DMA_MEM_TO_DEV) {
+ dma_src += copy;
+ } else if (chan->dir == DMA_DEV_TO_MEM) {
+ dma_dst += copy;
+ } else if (chan->dir == DMA_MEM_TO_MEM) {
+ dma_src += copy;
+ dma_dst += copy;
+ }
+
+ /* Insert the link descriptor to the LD ring */
+ list_add_tail(&new->node, &first->tx_list);
+ } while (len);
+
+ first->async_tx.flags = flags; /* client is in control of this ack */
+ first->async_tx.cookie = -EBUSY;
+
+ /* last desc and fire IRQ */
+ new->desc.ddadr = DDADR_STOP;
+ new->desc.dcmd |= DCMD_ENDIRQEN;
+
+ chan->cyclic_first = NULL;
+
+ return &first->async_tx;
+
+fail:
+ if (first)
+ mmp_pdma_free_desc_list(chan, &first->tx_list);
+ return NULL;
+}
+
+static struct dma_async_tx_descriptor *
+mmp_pdma_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
+ unsigned int sg_len, enum dma_transfer_direction dir,
+ unsigned long flags, void *context)
+{
+ struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
+ struct mmp_pdma_desc_sw *first = NULL, *prev = NULL, *new = NULL;
+ size_t len, avail;
+ struct scatterlist *sg;
+ dma_addr_t addr;
+ int i;
+
+ if ((sgl == NULL) || (sg_len == 0))
+ return NULL;
+
+ chan->byte_align = false;
+
+ for_each_sg(sgl, sg, sg_len, i) {
+ addr = sg_dma_address(sg);
+ avail = sg_dma_len(sgl);
+
+ do {
+ len = min_t(size_t, avail, PDMA_MAX_DESC_BYTES);
+ if (addr & 0x7)
+ chan->byte_align = true;
+
+ /* allocate and populate the descriptor */
+ new = mmp_pdma_alloc_descriptor(chan);
+ if (!new) {
+ dev_err(chan->dev, "no memory for desc\n");
+ goto fail;
+ }
+
+ new->desc.dcmd = chan->dcmd | (DCMD_LENGTH & len);
+ if (dir == DMA_MEM_TO_DEV) {
+ new->desc.dsadr = addr;
+ new->desc.dtadr = chan->dev_addr;
+ } else {
+ new->desc.dsadr = chan->dev_addr;
+ new->desc.dtadr = addr;
+ }
+
+ if (!first)
+ first = new;
+ else
+ prev->desc.ddadr = new->async_tx.phys;
+
+ new->async_tx.cookie = 0;
+ async_tx_ack(&new->async_tx);
+ prev = new;
+
+ /* Insert the link descriptor to the LD ring */
+ list_add_tail(&new->node, &first->tx_list);
+
+ /* update metadata */
+ addr += len;
+ avail -= len;
+ } while (avail);
+ }
+
+ first->async_tx.cookie = -EBUSY;
+ first->async_tx.flags = flags;
+
+ /* last desc and fire IRQ */
+ new->desc.ddadr = DDADR_STOP;
+ new->desc.dcmd |= DCMD_ENDIRQEN;
+
+ chan->dir = dir;
+ chan->cyclic_first = NULL;
+
+ return &first->async_tx;
+
+fail:
+ if (first)
+ mmp_pdma_free_desc_list(chan, &first->tx_list);
+ return NULL;
+}
+
+static struct dma_async_tx_descriptor *
+mmp_pdma_prep_dma_cyclic(struct dma_chan *dchan,
+ dma_addr_t buf_addr, size_t len, size_t period_len,
+ enum dma_transfer_direction direction,
+ unsigned long flags)
+{
+ struct mmp_pdma_chan *chan;
+ struct mmp_pdma_desc_sw *first = NULL, *prev = NULL, *new;
+ dma_addr_t dma_src, dma_dst;
+
+ if (!dchan || !len || !period_len)
+ return NULL;
+
+ /* the buffer length must be a multiple of period_len */
+ if (len % period_len != 0)
+ return NULL;
+
+ if (period_len > PDMA_MAX_DESC_BYTES)
+ return NULL;
+
+ chan = to_mmp_pdma_chan(dchan);
+
+ switch (direction) {
+ case DMA_MEM_TO_DEV:
+ dma_src = buf_addr;
+ dma_dst = chan->dev_addr;
+ break;
+ case DMA_DEV_TO_MEM:
+ dma_dst = buf_addr;
+ dma_src = chan->dev_addr;
+ break;
+ default:
+ dev_err(chan->dev, "Unsupported direction for cyclic DMA\n");
+ return NULL;
+ }
+
+ chan->dir = direction;
+
+ do {
+ /* Allocate the link descriptor from DMA pool */
+ new = mmp_pdma_alloc_descriptor(chan);
+ if (!new) {
+ dev_err(chan->dev, "no memory for desc\n");
+ goto fail;
+ }
+
+ new->desc.dcmd = (chan->dcmd | DCMD_ENDIRQEN |
+ (DCMD_LENGTH & period_len));
+ new->desc.dsadr = dma_src;
+ new->desc.dtadr = dma_dst;
+
+ if (!first)
+ first = new;
+ else
+ prev->desc.ddadr = new->async_tx.phys;
+
+ new->async_tx.cookie = 0;
+ async_tx_ack(&new->async_tx);
+
+ prev = new;
+ len -= period_len;
+
+ if (chan->dir == DMA_MEM_TO_DEV)
+ dma_src += period_len;
+ else
+ dma_dst += period_len;
+
+ /* Insert the link descriptor to the LD ring */
+ list_add_tail(&new->node, &first->tx_list);
+ } while (len);
+
+ first->async_tx.flags = flags; /* client is in control of this ack */
+ first->async_tx.cookie = -EBUSY;
+
+ /* make the cyclic link */
+ new->desc.ddadr = first->async_tx.phys;
+ chan->cyclic_first = first;
+
+ return &first->async_tx;
+
+fail:
+ if (first)
+ mmp_pdma_free_desc_list(chan, &first->tx_list);
+ return NULL;
+}
+
+static int mmp_pdma_config(struct dma_chan *dchan,
+ struct dma_slave_config *cfg)
+{
+ struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
+ u32 maxburst = 0, addr = 0;
+ enum dma_slave_buswidth width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
+
+ if (!dchan)
+ return -EINVAL;
+
+ if (cfg->direction == DMA_DEV_TO_MEM) {
+ chan->dcmd = DCMD_INCTRGADDR | DCMD_FLOWSRC;
+ maxburst = cfg->src_maxburst;
+ width = cfg->src_addr_width;
+ addr = cfg->src_addr;
+ } else if (cfg->direction == DMA_MEM_TO_DEV) {
+ chan->dcmd = DCMD_INCSRCADDR | DCMD_FLOWTRG;
+ maxburst = cfg->dst_maxburst;
+ width = cfg->dst_addr_width;
+ addr = cfg->dst_addr;
+ }
+
+ if (width == DMA_SLAVE_BUSWIDTH_1_BYTE)
+ chan->dcmd |= DCMD_WIDTH1;
+ else if (width == DMA_SLAVE_BUSWIDTH_2_BYTES)
+ chan->dcmd |= DCMD_WIDTH2;
+ else if (width == DMA_SLAVE_BUSWIDTH_4_BYTES)
+ chan->dcmd |= DCMD_WIDTH4;
+
+ if (maxburst == 8)
+ chan->dcmd |= DCMD_BURST8;
+ else if (maxburst == 16)
+ chan->dcmd |= DCMD_BURST16;
+ else if (maxburst == 32)
+ chan->dcmd |= DCMD_BURST32;
+
+ chan->dir = cfg->direction;
+ chan->dev_addr = addr;
+ /* FIXME: drivers should be ported over to use the filter
+ * function. Once that's done, the following two lines can
+ * be removed.
+ */
+ if (cfg->slave_id)
+ chan->drcmr = cfg->slave_id;
+
+ return 0;
+}
+
+static int mmp_pdma_terminate_all(struct dma_chan *dchan)
+{
+ struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
+ unsigned long flags;
+
+ if (!dchan)
+ return -EINVAL;
+
+ disable_chan(chan->phy);
+ mmp_pdma_free_phy(chan);
+ spin_lock_irqsave(&chan->desc_lock, flags);
+ mmp_pdma_free_desc_list(chan, &chan->chain_pending);
+ mmp_pdma_free_desc_list(chan, &chan->chain_running);
+ spin_unlock_irqrestore(&chan->desc_lock, flags);
+ chan->idle = true;
+
+ return 0;
+}
+
+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;
+ bool passed = false;
+ bool cyclic = chan->cyclic_first != NULL;
+
+ /*
+ * If the channel does not have a phy pointer anymore, it has already
+ * been completed. Therefore, its residue is 0.
+ */
+ if (!chan->phy)
+ return 0;
+
+ if (chan->dir == DMA_DEV_TO_MEM)
+ curr = readl(chan->phy->base + DTADR(chan->phy->idx));
+ else
+ curr = readl(chan->phy->base + DSADR(chan->phy->idx));
+
+ list_for_each_entry(sw, &chan->chain_running, node) {
+ u32 start, end, len;
+
+ if (chan->dir == DMA_DEV_TO_MEM)
+ start = sw->desc.dtadr;
+ else
+ start = sw->desc.dsadr;
+
+ len = sw->desc.dcmd & DCMD_LENGTH;
+ end = start + len;
+
+ /*
+ * 'passed' will be latched once we found the descriptor which
+ * lies inside the boundaries of the curr pointer. All
+ * descriptors that occur in the list _after_ we found that
+ * partially handled descriptor are still to be processed and
+ * are hence added to the residual bytes counter.
+ */
+
+ if (passed) {
+ residue += len;
+ } else if (curr >= start && curr <= end) {
+ residue += end - curr;
+ passed = true;
+ }
+
+ /*
+ * Descriptors that have the ENDIRQEN bit set mark the end of a
+ * transaction chain, and the cookie assigned with it has been
+ * returned previously from mmp_pdma_tx_submit().
+ *
+ * In case we have multiple transactions in the running chain,
+ * and the cookie does not match the one the user asked us
+ * about, reset the state variables and start over.
+ *
+ * This logic does not apply to cyclic transactions, where all
+ * descriptors have the ENDIRQEN bit set, and for which we
+ * can't have multiple transactions on one channel anyway.
+ */
+ if (cyclic || !(sw->desc.dcmd & DCMD_ENDIRQEN))
+ continue;
+
+ if (sw->async_tx.cookie == cookie) {
+ return residue;
+ } else {
+ residue = 0;
+ passed = false;
+ }
+ }
+
+ /* We should only get here in case of cyclic transactions */
+ return residue;
+}
+
+static enum dma_status mmp_pdma_tx_status(struct dma_chan *dchan,
+ dma_cookie_t cookie,
+ struct dma_tx_state *txstate)
+{
+ struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
+ enum dma_status ret;
+
+ ret = dma_cookie_status(dchan, cookie, txstate);
+ if (likely(ret != DMA_ERROR))
+ dma_set_residue(txstate, mmp_pdma_residue(chan, cookie));
+
+ return ret;
+}
+
+/**
+ * mmp_pdma_issue_pending - Issue the DMA start command
+ * pending list ==> running list
+ */
+static void mmp_pdma_issue_pending(struct dma_chan *dchan)
+{
+ struct mmp_pdma_chan *chan = to_mmp_pdma_chan(dchan);
+ unsigned long flags;
+
+ spin_lock_irqsave(&chan->desc_lock, flags);
+ start_pending_queue(chan);
+ spin_unlock_irqrestore(&chan->desc_lock, flags);
+}
+
+/*
+ * dma_do_tasklet
+ * Do call back
+ * Start pending list
+ */
+static void dma_do_tasklet(unsigned long data)
+{
+ struct mmp_pdma_chan *chan = (struct mmp_pdma_chan *)data;
+ struct mmp_pdma_desc_sw *desc, *_desc;
+ LIST_HEAD(chain_cleanup);
+ unsigned long flags;
+
+ if (chan->cyclic_first) {
+ dma_async_tx_callback cb = NULL;
+ void *cb_data = NULL;
+
+ spin_lock_irqsave(&chan->desc_lock, flags);
+ desc = chan->cyclic_first;
+ cb = desc->async_tx.callback;
+ cb_data = desc->async_tx.callback_param;
+ spin_unlock_irqrestore(&chan->desc_lock, flags);
+
+ if (cb)
+ cb(cb_data);
+
+ return;
+ }
+
+ /* submit pending list; callback for each desc; free desc */
+ spin_lock_irqsave(&chan->desc_lock, flags);
+
+ list_for_each_entry_safe(desc, _desc, &chan->chain_running, node) {
+ /*
+ * move the descriptors to a temporary list so we can drop
+ * the lock during the entire cleanup operation
+ */
+ list_move(&desc->node, &chain_cleanup);
+
+ /*
+ * Look for the first list entry which has the ENDIRQEN flag
+ * set. That is the descriptor we got an interrupt for, so
+ * complete that transaction and its cookie.
+ */
+ if (desc->desc.dcmd & DCMD_ENDIRQEN) {
+ dma_cookie_t cookie = desc->async_tx.cookie;
+ dma_cookie_complete(&desc->async_tx);
+ dev_dbg(chan->dev, "completed_cookie=%d\n", cookie);
+ break;
+ }
+ }
+
+ /*
+ * The hardware is idle and ready for more when the
+ * chain_running list is empty.
+ */
+ chan->idle = list_empty(&chan->chain_running);
+
+ /* Start any pending transactions automatically */
+ start_pending_queue(chan);
+ spin_unlock_irqrestore(&chan->desc_lock, flags);
+
+ /* Run the callback for each descriptor, in order */
+ list_for_each_entry_safe(desc, _desc, &chain_cleanup, node) {
+ struct dma_async_tx_descriptor *txd = &desc->async_tx;
+
+ /* Remove from the list of transactions */
+ list_del(&desc->node);
+ /* Run the link descriptor callback function */
+ if (txd->callback)
+ txd->callback(txd->callback_param);
+
+ dma_pool_free(chan->desc_pool, desc, txd->phys);
+ }
+}
+
+static int mmp_pdma_remove(struct platform_device *op)
+{
+ struct mmp_pdma_device *pdev = platform_get_drvdata(op);
+
+ dma_async_device_unregister(&pdev->device);
+ return 0;
+}
+
+static int mmp_pdma_chan_init(struct mmp_pdma_device *pdev, int idx, int irq)
+{
+ struct mmp_pdma_phy *phy = &pdev->phy[idx];
+ struct mmp_pdma_chan *chan;
+ int ret;
+
+ chan = devm_kzalloc(pdev->dev, sizeof(*chan), GFP_KERNEL);
+ if (chan == NULL)
+ return -ENOMEM;
+
+ phy->idx = idx;
+ phy->base = pdev->base;
+
+ if (irq) {
+ ret = devm_request_irq(pdev->dev, irq, mmp_pdma_chan_handler,
+ IRQF_SHARED, "pdma", phy);
+ if (ret) {
+ dev_err(pdev->dev, "channel request irq fail!\n");
+ return ret;
+ }
+ }
+
+ spin_lock_init(&chan->desc_lock);
+ chan->dev = pdev->dev;
+ chan->chan.device = &pdev->device;
+ tasklet_init(&chan->tasklet, dma_do_tasklet, (unsigned long)chan);
+ INIT_LIST_HEAD(&chan->chain_pending);
+ INIT_LIST_HEAD(&chan->chain_running);
+
+ /* register virt channel to dma engine */
+ list_add_tail(&chan->chan.device_node, &pdev->device.channels);
+
+ return 0;
+}
+
+static const struct of_device_id mmp_pdma_dt_ids[] = {
+ { .compatible = "marvell,pdma-1.0", },
+ {}
+};
+MODULE_DEVICE_TABLE(of, mmp_pdma_dt_ids);
+
+static struct dma_chan *mmp_pdma_dma_xlate(struct of_phandle_args *dma_spec,
+ struct of_dma *ofdma)
+{
+ struct mmp_pdma_device *d = ofdma->of_dma_data;
+ struct dma_chan *chan;
+
+ chan = dma_get_any_slave_channel(&d->device);
+ if (!chan)
+ return NULL;
+
+ to_mmp_pdma_chan(chan)->drcmr = dma_spec->args[0];
+
+ return chan;
+}
+
+static int mmp_pdma_probe(struct platform_device *op)
+{
+ struct mmp_pdma_device *pdev;
+ const struct of_device_id *of_id;
+ struct mmp_dma_platdata *pdata = dev_get_platdata(&op->dev);
+ struct resource *iores;
+ int i, ret, irq = 0;
+ int dma_channels = 0, irq_num = 0;
+ const enum dma_slave_buswidth widths =
+ DMA_SLAVE_BUSWIDTH_1_BYTE | DMA_SLAVE_BUSWIDTH_2_BYTES |
+ DMA_SLAVE_BUSWIDTH_4_BYTES;
+
+ pdev = devm_kzalloc(&op->dev, sizeof(*pdev), GFP_KERNEL);
+ if (!pdev)
+ return -ENOMEM;
+
+ pdev->dev = &op->dev;
+
+ spin_lock_init(&pdev->phy_lock);
+
+ iores = platform_get_resource(op, IORESOURCE_MEM, 0);
+ pdev->base = devm_ioremap_resource(pdev->dev, iores);
+ if (IS_ERR(pdev->base))
+ return PTR_ERR(pdev->base);
+
+ of_id = of_match_device(mmp_pdma_dt_ids, pdev->dev);
+ if (of_id)
+ of_property_read_u32(pdev->dev->of_node, "#dma-channels",
+ &dma_channels);
+ else if (pdata && pdata->dma_channels)
+ dma_channels = pdata->dma_channels;
+ else
+ dma_channels = 32; /* default 32 channel */
+ pdev->dma_channels = dma_channels;
+
+ for (i = 0; i < dma_channels; i++) {
+ if (platform_get_irq(op, i) > 0)
+ irq_num++;
+ }
+
+ pdev->phy = devm_kcalloc(pdev->dev, dma_channels, sizeof(*pdev->phy),
+ GFP_KERNEL);
+ if (pdev->phy == NULL)
+ return -ENOMEM;
+
+ INIT_LIST_HEAD(&pdev->device.channels);
+
+ if (irq_num != dma_channels) {
+ /* all chan share one irq, demux inside */
+ irq = platform_get_irq(op, 0);
+ ret = devm_request_irq(pdev->dev, irq, mmp_pdma_int_handler,
+ IRQF_SHARED, "pdma", pdev);
+ if (ret)
+ return ret;
+ }
+
+ for (i = 0; i < dma_channels; i++) {
+ irq = (irq_num != dma_channels) ? 0 : platform_get_irq(op, i);
+ ret = mmp_pdma_chan_init(pdev, i, irq);
+ if (ret)
+ return ret;
+ }
+
+ dma_cap_set(DMA_SLAVE, pdev->device.cap_mask);
+ dma_cap_set(DMA_MEMCPY, pdev->device.cap_mask);
+ dma_cap_set(DMA_CYCLIC, pdev->device.cap_mask);
+ dma_cap_set(DMA_PRIVATE, pdev->device.cap_mask);
+ pdev->device.dev = &op->dev;
+ pdev->device.device_alloc_chan_resources = mmp_pdma_alloc_chan_resources;
+ pdev->device.device_free_chan_resources = mmp_pdma_free_chan_resources;
+ pdev->device.device_tx_status = mmp_pdma_tx_status;
+ pdev->device.device_prep_dma_memcpy = mmp_pdma_prep_memcpy;
+ pdev->device.device_prep_slave_sg = mmp_pdma_prep_slave_sg;
+ pdev->device.device_prep_dma_cyclic = mmp_pdma_prep_dma_cyclic;
+ pdev->device.device_issue_pending = mmp_pdma_issue_pending;
+ pdev->device.device_config = mmp_pdma_config;
+ pdev->device.device_terminate_all = mmp_pdma_terminate_all;
+ pdev->device.copy_align = PDMA_ALIGNMENT;
+ pdev->device.src_addr_widths = widths;
+ pdev->device.dst_addr_widths = widths;
+ 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)
+ dma_set_mask(pdev->dev, pdev->dev->coherent_dma_mask);
+ else
+ dma_set_mask(pdev->dev, DMA_BIT_MASK(64));
+
+ ret = dma_async_device_register(&pdev->device);
+ if (ret) {
+ dev_err(pdev->device.dev, "unable to register\n");
+ return ret;
+ }
+
+ if (op->dev.of_node) {
+ /* Device-tree DMA controller registration */
+ ret = of_dma_controller_register(op->dev.of_node,
+ mmp_pdma_dma_xlate, pdev);
+ if (ret < 0) {
+ dev_err(&op->dev, "of_dma_controller_register failed\n");
+ return ret;
+ }
+ }
+
+ platform_set_drvdata(op, pdev);
+ dev_info(pdev->device.dev, "initialized %d channels\n", dma_channels);
+ return 0;
+}
+
+static const struct platform_device_id mmp_pdma_id_table[] = {
+ { "mmp-pdma", },
+ { },
+};
+
+static struct platform_driver mmp_pdma_driver = {
+ .driver = {
+ .name = "mmp-pdma",
+ .of_match_table = mmp_pdma_dt_ids,
+ },
+ .id_table = mmp_pdma_id_table,
+ .probe = mmp_pdma_probe,
+ .remove = mmp_pdma_remove,
+};
+
+bool mmp_pdma_filter_fn(struct dma_chan *chan, void *param)
+{
+ struct mmp_pdma_chan *c = to_mmp_pdma_chan(chan);
+
+ if (chan->device->dev->driver != &mmp_pdma_driver.driver)
+ return false;
+
+ c->drcmr = *(unsigned int *)param;
+
+ return true;
+}
+EXPORT_SYMBOL_GPL(mmp_pdma_filter_fn);
+
+module_platform_driver(mmp_pdma_driver);
+
+MODULE_DESCRIPTION("MARVELL MMP Peripheral DMA Driver");
+MODULE_AUTHOR("Marvell International Ltd.");
+MODULE_LICENSE("GPL v2");