]> git.karo-electronics.de Git - karo-tx-linux.git/blobdiff - drivers/dma/dw_dmac.c
Merge branch 'next' of git://git.infradead.org/users/vkoul/slave-dma
[karo-tx-linux.git] / drivers / dma / dw_dmac.c
index b33d1f6e13332400beab684bee3a092776531854..51c3ea2ed41af67e26dc09169fb51fbcc6117ac4 100644 (file)
@@ -1,6 +1,5 @@
 /*
- * Driver for the Synopsys DesignWare DMA Controller (aka DMACA on
- * AVR32 systems.)
+ * Core driver for the Synopsys DesignWare DMA Controller
  *
  * Copyright (C) 2007-2008 Atmel Corporation
  * Copyright (C) 2010-2011 ST Microelectronics
@@ -9,11 +8,13 @@
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */
+
 #include <linux/bitops.h>
 #include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/dmaengine.h>
 #include <linux/dma-mapping.h>
+#include <linux/dmapool.h>
 #include <linux/err.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
@@ -47,15 +48,32 @@ static inline unsigned int dwc_get_sms(struct dw_dma_slave *slave)
        return slave ? slave->src_master : 1;
 }
 
+#define SRC_MASTER     0
+#define DST_MASTER     1
+
+static inline unsigned int dwc_get_master(struct dma_chan *chan, int master)
+{
+       struct dw_dma *dw = to_dw_dma(chan->device);
+       struct dw_dma_slave *dws = chan->private;
+       unsigned int m;
+
+       if (master == SRC_MASTER)
+               m = dwc_get_sms(dws);
+       else
+               m = dwc_get_dms(dws);
+
+       return min_t(unsigned int, dw->nr_masters - 1, m);
+}
+
 #define DWC_DEFAULT_CTLLO(_chan) ({                            \
-               struct dw_dma_slave *__slave = (_chan->private);        \
                struct dw_dma_chan *_dwc = to_dw_dma_chan(_chan);       \
                struct dma_slave_config *_sconfig = &_dwc->dma_sconfig; \
-               int _dms = dwc_get_dms(__slave);                \
-               int _sms = dwc_get_sms(__slave);                \
-               u8 _smsize = __slave ? _sconfig->src_maxburst : \
+               bool _is_slave = is_slave_direction(_dwc->direction);   \
+               int _dms = dwc_get_master(_chan, DST_MASTER);           \
+               int _sms = dwc_get_master(_chan, SRC_MASTER);           \
+               u8 _smsize = _is_slave ? _sconfig->src_maxburst :       \
                        DW_DMA_MSIZE_16;                        \
-               u8 _dmsize = __slave ? _sconfig->dst_maxburst : \
+               u8 _dmsize = _is_slave ? _sconfig->dst_maxburst :       \
                        DW_DMA_MSIZE_16;                        \
                                                                \
                (DWC_CTLL_DST_MSIZE(_dmsize)                    \
@@ -73,15 +91,14 @@ static inline unsigned int dwc_get_sms(struct dw_dma_slave *slave)
  */
 #define NR_DESCS_PER_CHANNEL   64
 
-/*----------------------------------------------------------------------*/
+static inline unsigned int dwc_get_data_width(struct dma_chan *chan, int master)
+{
+       struct dw_dma *dw = to_dw_dma(chan->device);
 
-/*
- * Because we're not relying on writeback from the controller (it may not
- * even be configured into the core!) we don't need to use dma_pool.  These
- * descriptors -- and associated data -- are cacheable.  We do need to make
- * sure their dcache entries are written back before handing them off to
- * the controller, though.
- */
+       return dw->data_width[dwc_get_master(chan, master)];
+}
+
+/*----------------------------------------------------------------------*/
 
 static struct device *chan2dev(struct dma_chan *chan)
 {
@@ -94,7 +111,7 @@ static struct device *chan2parent(struct dma_chan *chan)
 
 static struct dw_desc *dwc_first_active(struct dw_dma_chan *dwc)
 {
-       return list_entry(dwc->active_list.next, struct dw_desc, desc_node);
+       return to_dw_desc(dwc->active_list.next);
 }
 
 static struct dw_desc *dwc_desc_get(struct dw_dma_chan *dwc)
@@ -121,19 +138,6 @@ static struct dw_desc *dwc_desc_get(struct dw_dma_chan *dwc)
        return ret;
 }
 
-static void dwc_sync_desc_for_cpu(struct dw_dma_chan *dwc, struct dw_desc *desc)
-{
-       struct dw_desc  *child;
-
-       list_for_each_entry(child, &desc->tx_list, desc_node)
-               dma_sync_single_for_cpu(chan2parent(&dwc->chan),
-                               child->txd.phys, sizeof(child->lli),
-                               DMA_TO_DEVICE);
-       dma_sync_single_for_cpu(chan2parent(&dwc->chan),
-                       desc->txd.phys, sizeof(desc->lli),
-                       DMA_TO_DEVICE);
-}
-
 /*
  * Move a descriptor, including any children, to the free list.
  * `desc' must not be on any lists.
@@ -145,8 +149,6 @@ static void dwc_desc_put(struct dw_dma_chan *dwc, struct dw_desc *desc)
        if (desc) {
                struct dw_desc *child;
 
-               dwc_sync_desc_for_cpu(dwc, desc);
-
                spin_lock_irqsave(&dwc->lock, flags);
                list_for_each_entry(child, &desc->tx_list, desc_node)
                        dev_vdbg(chan2dev(&dwc->chan),
@@ -179,9 +181,9 @@ static void dwc_initialize(struct dw_dma_chan *dwc)
                cfghi = dws->cfg_hi;
                cfglo |= dws->cfg_lo & ~DWC_CFGL_CH_PRIOR_MASK;
        } else {
-               if (dwc->dma_sconfig.direction == DMA_MEM_TO_DEV)
+               if (dwc->direction == DMA_MEM_TO_DEV)
                        cfghi = DWC_CFGH_DST_PER(dwc->dma_sconfig.slave_id);
-               else if (dwc->dma_sconfig.direction == DMA_DEV_TO_MEM)
+               else if (dwc->direction == DMA_DEV_TO_MEM)
                        cfghi = DWC_CFGH_SRC_PER(dwc->dma_sconfig.slave_id);
        }
 
@@ -223,7 +225,6 @@ static inline void dwc_dump_chan_regs(struct dw_dma_chan *dwc)
                channel_readl(dwc, CTL_LO));
 }
 
-
 static inline void dwc_chan_disable(struct dw_dma *dw, struct dw_dma_chan *dwc)
 {
        channel_clear_bit(dw, CH_EN, dwc->mask);
@@ -249,6 +250,9 @@ static inline void dwc_do_single_block(struct dw_dma_chan *dwc,
        channel_writel(dwc, CTL_LO, ctllo);
        channel_writel(dwc, CTL_HI, desc->lli.ctlhi);
        channel_set_bit(dw, CH_EN, dwc->mask);
+
+       /* Move pointer to next descriptor */
+       dwc->tx_node_active = dwc->tx_node_active->next;
 }
 
 /* Called with dwc->lock held and bh disabled */
@@ -279,9 +283,10 @@ static void dwc_dostart(struct dw_dma_chan *dwc, struct dw_desc *first)
 
                dwc_initialize(dwc);
 
-               dwc->tx_list = &first->tx_list;
-               dwc->tx_node_active = first->tx_list.next;
+               dwc->residue = first->total_len;
+               dwc->tx_node_active = &first->tx_list;
 
+               /* Submit first block */
                dwc_do_single_block(dwc, first);
 
                return;
@@ -317,8 +322,6 @@ dwc_descriptor_complete(struct dw_dma_chan *dwc, struct dw_desc *desc,
                param = txd->callback_param;
        }
 
-       dwc_sync_desc_for_cpu(dwc, desc);
-
        /* async_tx_ack */
        list_for_each_entry(child, &desc->tx_list, desc_node)
                async_tx_ack(&child->txd);
@@ -327,29 +330,29 @@ dwc_descriptor_complete(struct dw_dma_chan *dwc, struct dw_desc *desc,
        list_splice_init(&desc->tx_list, &dwc->free_list);
        list_move(&desc->desc_node, &dwc->free_list);
 
-       if (!dwc->chan.private) {
+       if (!is_slave_direction(dwc->direction)) {
                struct device *parent = chan2parent(&dwc->chan);
                if (!(txd->flags & DMA_COMPL_SKIP_DEST_UNMAP)) {
                        if (txd->flags & DMA_COMPL_DEST_UNMAP_SINGLE)
                                dma_unmap_single(parent, desc->lli.dar,
-                                               desc->len, DMA_FROM_DEVICE);
+                                       desc->total_len, DMA_FROM_DEVICE);
                        else
                                dma_unmap_page(parent, desc->lli.dar,
-                                               desc->len, DMA_FROM_DEVICE);
+                                       desc->total_len, DMA_FROM_DEVICE);
                }
                if (!(txd->flags & DMA_COMPL_SKIP_SRC_UNMAP)) {
                        if (txd->flags & DMA_COMPL_SRC_UNMAP_SINGLE)
                                dma_unmap_single(parent, desc->lli.sar,
-                                               desc->len, DMA_TO_DEVICE);
+                                       desc->total_len, DMA_TO_DEVICE);
                        else
                                dma_unmap_page(parent, desc->lli.sar,
-                                               desc->len, DMA_TO_DEVICE);
+                                       desc->total_len, DMA_TO_DEVICE);
                }
        }
 
        spin_unlock_irqrestore(&dwc->lock, flags);
 
-       if (callback_required && callback)
+       if (callback)
                callback(param);
 }
 
@@ -384,6 +387,15 @@ static void dwc_complete_all(struct dw_dma *dw, struct dw_dma_chan *dwc)
                dwc_descriptor_complete(dwc, desc, true);
 }
 
+/* Returns how many bytes were already received from source */
+static inline u32 dwc_get_sent(struct dw_dma_chan *dwc)
+{
+       u32 ctlhi = channel_readl(dwc, CTL_HI);
+       u32 ctllo = channel_readl(dwc, CTL_LO);
+
+       return (ctlhi & DWC_CTLH_BLOCK_TS_MASK) * (1 << (ctllo >> 4 & 7));
+}
+
 static void dwc_scan_descriptors(struct dw_dma *dw, struct dw_dma_chan *dwc)
 {
        dma_addr_t llp;
@@ -399,6 +411,39 @@ static void dwc_scan_descriptors(struct dw_dma *dw, struct dw_dma_chan *dwc)
        if (status_xfer & dwc->mask) {
                /* Everything we've submitted is done */
                dma_writel(dw, CLEAR.XFER, dwc->mask);
+
+               if (test_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags)) {
+                       struct list_head *head, *active = dwc->tx_node_active;
+
+                       /*
+                        * We are inside first active descriptor.
+                        * Otherwise something is really wrong.
+                        */
+                       desc = dwc_first_active(dwc);
+
+                       head = &desc->tx_list;
+                       if (active != head) {
+                               /* Update desc to reflect last sent one */
+                               if (active != head->next)
+                                       desc = to_dw_desc(active->prev);
+
+                               dwc->residue -= desc->len;
+
+                               child = to_dw_desc(active);
+
+                               /* Submit next block */
+                               dwc_do_single_block(dwc, child);
+
+                               spin_unlock_irqrestore(&dwc->lock, flags);
+                               return;
+                       }
+
+                       /* We are done here */
+                       clear_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags);
+               }
+
+               dwc->residue = 0;
+
                spin_unlock_irqrestore(&dwc->lock, flags);
 
                dwc_complete_all(dw, dwc);
@@ -406,6 +451,13 @@ static void dwc_scan_descriptors(struct dw_dma *dw, struct dw_dma_chan *dwc)
        }
 
        if (list_empty(&dwc->active_list)) {
+               dwc->residue = 0;
+               spin_unlock_irqrestore(&dwc->lock, flags);
+               return;
+       }
+
+       if (test_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags)) {
+               dev_vdbg(chan2dev(&dwc->chan), "%s: soft LLP mode\n", __func__);
                spin_unlock_irqrestore(&dwc->lock, flags);
                return;
        }
@@ -414,6 +466,9 @@ static void dwc_scan_descriptors(struct dw_dma *dw, struct dw_dma_chan *dwc)
                        (unsigned long long)llp);
 
        list_for_each_entry_safe(desc, _desc, &dwc->active_list, desc_node) {
+               /* initial residue value */
+               dwc->residue = desc->total_len;
+
                /* check first descriptors addr */
                if (desc->txd.phys == llp) {
                        spin_unlock_irqrestore(&dwc->lock, flags);
@@ -423,16 +478,21 @@ static void dwc_scan_descriptors(struct dw_dma *dw, struct dw_dma_chan *dwc)
                /* check first descriptors llp */
                if (desc->lli.llp == llp) {
                        /* This one is currently in progress */
+                       dwc->residue -= dwc_get_sent(dwc);
                        spin_unlock_irqrestore(&dwc->lock, flags);
                        return;
                }
 
-               list_for_each_entry(child, &desc->tx_list, desc_node)
+               dwc->residue -= desc->len;
+               list_for_each_entry(child, &desc->tx_list, desc_node) {
                        if (child->lli.llp == llp) {
                                /* Currently in progress */
+                               dwc->residue -= dwc_get_sent(dwc);
                                spin_unlock_irqrestore(&dwc->lock, flags);
                                return;
                        }
+                       dwc->residue -= child->len;
+               }
 
                /*
                 * No descriptors so far seem to be in progress, i.e.
@@ -458,9 +518,8 @@ static void dwc_scan_descriptors(struct dw_dma *dw, struct dw_dma_chan *dwc)
 
 static inline void dwc_dump_lli(struct dw_dma_chan *dwc, struct dw_lli *lli)
 {
-       dev_printk(KERN_CRIT, chan2dev(&dwc->chan),
-                       "  desc: s0x%x d0x%x l0x%x c0x%x:%x\n",
-                       lli->sar, lli->dar, lli->llp, lli->ctlhi, lli->ctllo);
+       dev_crit(chan2dev(&dwc->chan), "  desc: s0x%x d0x%x l0x%x c0x%x:%x\n",
+                lli->sar, lli->dar, lli->llp, lli->ctlhi, lli->ctllo);
 }
 
 static void dwc_handle_error(struct dw_dma *dw, struct dw_dma_chan *dwc)
@@ -488,16 +547,14 @@ static void dwc_handle_error(struct dw_dma *dw, struct dw_dma_chan *dwc)
                dwc_dostart(dwc, dwc_first_active(dwc));
 
        /*
-        * KERN_CRITICAL may seem harsh, but since this only happens
+        * WARN may seem harsh, but since this only happens
         * when someone submits a bad physical address in a
         * descriptor, we should consider ourselves lucky that the
         * controller flagged an error instead of scribbling over
         * random memory locations.
         */
-       dev_printk(KERN_CRIT, chan2dev(&dwc->chan),
-                       "Bad descriptor submitted for DMA!\n");
-       dev_printk(KERN_CRIT, chan2dev(&dwc->chan),
-                       "  cookie: %d\n", bad_desc->txd.cookie);
+       dev_WARN(chan2dev(&dwc->chan), "Bad descriptor submitted for DMA!\n"
+                                      "  cookie: %d\n", bad_desc->txd.cookie);
        dwc_dump_lli(dwc, &bad_desc->lli);
        list_for_each_entry(child, &bad_desc->tx_list, desc_node)
                dwc_dump_lli(dwc, &child->lli);
@@ -598,36 +655,8 @@ static void dw_dma_tasklet(unsigned long data)
                        dwc_handle_cyclic(dw, dwc, status_err, status_xfer);
                else if (status_err & (1 << i))
                        dwc_handle_error(dw, dwc);
-               else if (status_xfer & (1 << i)) {
-                       unsigned long flags;
-
-                       spin_lock_irqsave(&dwc->lock, flags);
-                       if (test_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags)) {
-                               if (dwc->tx_node_active != dwc->tx_list) {
-                                       struct dw_desc *desc =
-                                               list_entry(dwc->tx_node_active,
-                                                          struct dw_desc,
-                                                          desc_node);
-
-                                       dma_writel(dw, CLEAR.XFER, dwc->mask);
-
-                                       /* move pointer to next descriptor */
-                                       dwc->tx_node_active =
-                                               dwc->tx_node_active->next;
-
-                                       dwc_do_single_block(dwc, desc);
-
-                                       spin_unlock_irqrestore(&dwc->lock, flags);
-                                       continue;
-                               } else {
-                                       /* we are done here */
-                                       clear_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags);
-                               }
-                       }
-                       spin_unlock_irqrestore(&dwc->lock, flags);
-
+               else if (status_xfer & (1 << i))
                        dwc_scan_descriptors(dw, dwc);
-               }
        }
 
        /*
@@ -709,7 +738,6 @@ dwc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
                size_t len, unsigned long flags)
 {
        struct dw_dma_chan      *dwc = to_dw_dma_chan(chan);
-       struct dw_dma_slave     *dws = chan->private;
        struct dw_desc          *desc;
        struct dw_desc          *first;
        struct dw_desc          *prev;
@@ -730,8 +758,10 @@ dwc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
                return NULL;
        }
 
-       data_width = min_t(unsigned int, dwc->dw->data_width[dwc_get_sms(dws)],
-                                        dwc->dw->data_width[dwc_get_dms(dws)]);
+       dwc->direction = DMA_MEM_TO_MEM;
+
+       data_width = min_t(unsigned int, dwc_get_data_width(chan, SRC_MASTER),
+                          dwc_get_data_width(chan, DST_MASTER));
 
        src_width = dst_width = min_t(unsigned int, data_width,
                                      dwc_fast_fls(src | dest | len));
@@ -756,32 +786,25 @@ dwc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
                desc->lli.dar = dest + offset;
                desc->lli.ctllo = ctllo;
                desc->lli.ctlhi = xfer_count;
+               desc->len = xfer_count << src_width;
 
                if (!first) {
                        first = desc;
                } else {
                        prev->lli.llp = desc->txd.phys;
-                       dma_sync_single_for_device(chan2parent(chan),
-                                       prev->txd.phys, sizeof(prev->lli),
-                                       DMA_TO_DEVICE);
                        list_add_tail(&desc->desc_node,
                                        &first->tx_list);
                }
                prev = desc;
        }
 
-
        if (flags & DMA_PREP_INTERRUPT)
                /* Trigger interrupt after last block */
                prev->lli.ctllo |= DWC_CTLL_INT_EN;
 
        prev->lli.llp = 0;
-       dma_sync_single_for_device(chan2parent(chan),
-                       prev->txd.phys, sizeof(prev->lli),
-                       DMA_TO_DEVICE);
-
        first->txd.flags = flags;
-       first->len = len;
+       first->total_len = len;
 
        return &first->txd;
 
@@ -796,7 +819,6 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
                unsigned long flags, void *context)
 {
        struct dw_dma_chan      *dwc = to_dw_dma_chan(chan);
-       struct dw_dma_slave     *dws = chan->private;
        struct dma_slave_config *sconfig = &dwc->dma_sconfig;
        struct dw_desc          *prev;
        struct dw_desc          *first;
@@ -811,9 +833,11 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
 
        dev_vdbg(chan2dev(chan), "%s\n", __func__);
 
-       if (unlikely(!dws || !sg_len))
+       if (unlikely(!is_slave_direction(direction) || !sg_len))
                return NULL;
 
+       dwc->direction = direction;
+
        prev = first = NULL;
 
        switch (direction) {
@@ -828,7 +852,7 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
                ctllo |= sconfig->device_fc ? DWC_CTLL_FC(DW_DMA_FC_P_M2P) :
                        DWC_CTLL_FC(DW_DMA_FC_D_M2P);
 
-               data_width = dwc->dw->data_width[dwc_get_sms(dws)];
+               data_width = dwc_get_data_width(chan, SRC_MASTER);
 
                for_each_sg(sgl, sg, sg_len, i) {
                        struct dw_desc  *desc;
@@ -861,15 +885,12 @@ slave_sg_todev_fill_desc:
                        }
 
                        desc->lli.ctlhi = dlen >> mem_width;
+                       desc->len = dlen;
 
                        if (!first) {
                                first = desc;
                        } else {
                                prev->lli.llp = desc->txd.phys;
-                               dma_sync_single_for_device(chan2parent(chan),
-                                               prev->txd.phys,
-                                               sizeof(prev->lli),
-                                               DMA_TO_DEVICE);
                                list_add_tail(&desc->desc_node,
                                                &first->tx_list);
                        }
@@ -891,7 +912,7 @@ slave_sg_todev_fill_desc:
                ctllo |= sconfig->device_fc ? DWC_CTLL_FC(DW_DMA_FC_P_P2M) :
                        DWC_CTLL_FC(DW_DMA_FC_D_P2M);
 
-               data_width = dwc->dw->data_width[dwc_get_dms(dws)];
+               data_width = dwc_get_data_width(chan, DST_MASTER);
 
                for_each_sg(sgl, sg, sg_len, i) {
                        struct dw_desc  *desc;
@@ -923,15 +944,12 @@ slave_sg_fromdev_fill_desc:
                                len = 0;
                        }
                        desc->lli.ctlhi = dlen >> reg_width;
+                       desc->len = dlen;
 
                        if (!first) {
                                first = desc;
                        } else {
                                prev->lli.llp = desc->txd.phys;
-                               dma_sync_single_for_device(chan2parent(chan),
-                                               prev->txd.phys,
-                                               sizeof(prev->lli),
-                                               DMA_TO_DEVICE);
                                list_add_tail(&desc->desc_node,
                                                &first->tx_list);
                        }
@@ -951,11 +969,7 @@ slave_sg_fromdev_fill_desc:
                prev->lli.ctllo |= DWC_CTLL_INT_EN;
 
        prev->lli.llp = 0;
-       dma_sync_single_for_device(chan2parent(chan),
-                       prev->txd.phys, sizeof(prev->lli),
-                       DMA_TO_DEVICE);
-
-       first->len = total_len;
+       first->total_len = total_len;
 
        return &first->txd;
 
@@ -985,11 +999,12 @@ set_runtime_config(struct dma_chan *chan, struct dma_slave_config *sconfig)
 {
        struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
 
-       /* Check if it is chan is configured for slave transfers */
-       if (!chan->private)
+       /* Check if chan will be configured for slave transfers */
+       if (!is_slave_direction(sconfig->direction))
                return -EINVAL;
 
        memcpy(&dwc->dma_sconfig, sconfig, sizeof(*sconfig));
+       dwc->direction = sconfig->direction;
 
        convert_burst(&dwc->dma_sconfig.src_maxburst);
        convert_burst(&dwc->dma_sconfig.dst_maxburst);
@@ -997,6 +1012,26 @@ set_runtime_config(struct dma_chan *chan, struct dma_slave_config *sconfig)
        return 0;
 }
 
+static inline void dwc_chan_pause(struct dw_dma_chan *dwc)
+{
+       u32 cfglo = channel_readl(dwc, CFG_LO);
+
+       channel_writel(dwc, CFG_LO, cfglo | DWC_CFGL_CH_SUSP);
+       while (!(channel_readl(dwc, CFG_LO) & DWC_CFGL_FIFO_EMPTY))
+               cpu_relax();
+
+       dwc->paused = true;
+}
+
+static inline void dwc_chan_resume(struct dw_dma_chan *dwc)
+{
+       u32 cfglo = channel_readl(dwc, CFG_LO);
+
+       channel_writel(dwc, CFG_LO, cfglo & ~DWC_CFGL_CH_SUSP);
+
+       dwc->paused = false;
+}
+
 static int dwc_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
                       unsigned long arg)
 {
@@ -1004,18 +1039,13 @@ static int dwc_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
        struct dw_dma           *dw = to_dw_dma(chan->device);
        struct dw_desc          *desc, *_desc;
        unsigned long           flags;
-       u32                     cfglo;
        LIST_HEAD(list);
 
        if (cmd == DMA_PAUSE) {
                spin_lock_irqsave(&dwc->lock, flags);
 
-               cfglo = channel_readl(dwc, CFG_LO);
-               channel_writel(dwc, CFG_LO, cfglo | DWC_CFGL_CH_SUSP);
-               while (!(channel_readl(dwc, CFG_LO) & DWC_CFGL_FIFO_EMPTY))
-                       cpu_relax();
+               dwc_chan_pause(dwc);
 
-               dwc->paused = true;
                spin_unlock_irqrestore(&dwc->lock, flags);
        } else if (cmd == DMA_RESUME) {
                if (!dwc->paused)
@@ -1023,9 +1053,7 @@ static int dwc_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
 
                spin_lock_irqsave(&dwc->lock, flags);
 
-               cfglo = channel_readl(dwc, CFG_LO);
-               channel_writel(dwc, CFG_LO, cfglo & ~DWC_CFGL_CH_SUSP);
-               dwc->paused = false;
+               dwc_chan_resume(dwc);
 
                spin_unlock_irqrestore(&dwc->lock, flags);
        } else if (cmd == DMA_TERMINATE_ALL) {
@@ -1035,7 +1063,7 @@ static int dwc_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
 
                dwc_chan_disable(dw, dwc);
 
-               dwc->paused = false;
+               dwc_chan_resume(dwc);
 
                /* active_list entries will end up before queued entries */
                list_splice_init(&dwc->queue, &list);
@@ -1055,6 +1083,21 @@ static int dwc_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
        return 0;
 }
 
+static inline u32 dwc_get_residue(struct dw_dma_chan *dwc)
+{
+       unsigned long flags;
+       u32 residue;
+
+       spin_lock_irqsave(&dwc->lock, flags);
+
+       residue = dwc->residue;
+       if (test_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags) && residue)
+               residue -= dwc_get_sent(dwc);
+
+       spin_unlock_irqrestore(&dwc->lock, flags);
+       return residue;
+}
+
 static enum dma_status
 dwc_tx_status(struct dma_chan *chan,
              dma_cookie_t cookie,
@@ -1071,7 +1114,7 @@ dwc_tx_status(struct dma_chan *chan,
        }
 
        if (ret != DMA_SUCCESS)
-               dma_set_residue(txstate, dwc_first_active(dwc)->len);
+               dma_set_residue(txstate, dwc_get_residue(dwc));
 
        if (dwc->paused)
                return DMA_PAUSED;
@@ -1114,22 +1157,22 @@ static int dwc_alloc_chan_resources(struct dma_chan *chan)
        spin_lock_irqsave(&dwc->lock, flags);
        i = dwc->descs_allocated;
        while (dwc->descs_allocated < NR_DESCS_PER_CHANNEL) {
+               dma_addr_t phys;
+
                spin_unlock_irqrestore(&dwc->lock, flags);
 
-               desc = kzalloc(sizeof(struct dw_desc), GFP_KERNEL);
-               if (!desc) {
-                       dev_info(chan2dev(chan),
-                               "only allocated %d descriptors\n", i);
-                       spin_lock_irqsave(&dwc->lock, flags);
-                       break;
-               }
+               desc = dma_pool_alloc(dw->desc_pool, GFP_ATOMIC, &phys);
+               if (!desc)
+                       goto err_desc_alloc;
+
+               memset(desc, 0, sizeof(struct dw_desc));
 
                INIT_LIST_HEAD(&desc->tx_list);
                dma_async_tx_descriptor_init(&desc->txd, chan);
                desc->txd.tx_submit = dwc_tx_submit;
                desc->txd.flags = DMA_CTRL_ACK;
-               desc->txd.phys = dma_map_single(chan2parent(chan), &desc->lli,
-                               sizeof(desc->lli), DMA_TO_DEVICE);
+               desc->txd.phys = phys;
+
                dwc_desc_put(dwc, desc);
 
                spin_lock_irqsave(&dwc->lock, flags);
@@ -1140,6 +1183,11 @@ static int dwc_alloc_chan_resources(struct dma_chan *chan)
 
        dev_dbg(chan2dev(chan), "%s: allocated %d descriptors\n", __func__, i);
 
+       return i;
+
+err_desc_alloc:
+       dev_info(chan2dev(chan), "only allocated %d descriptors\n", i);
+
        return i;
 }
 
@@ -1172,14 +1220,56 @@ static void dwc_free_chan_resources(struct dma_chan *chan)
 
        list_for_each_entry_safe(desc, _desc, &list, desc_node) {
                dev_vdbg(chan2dev(chan), "  freeing descriptor %p\n", desc);
-               dma_unmap_single(chan2parent(chan), desc->txd.phys,
-                               sizeof(desc->lli), DMA_TO_DEVICE);
-               kfree(desc);
+               dma_pool_free(dw->desc_pool, desc, desc->txd.phys);
        }
 
        dev_vdbg(chan2dev(chan), "%s: done\n", __func__);
 }
 
+bool dw_dma_generic_filter(struct dma_chan *chan, void *param)
+{
+       struct dw_dma *dw = to_dw_dma(chan->device);
+       static struct dw_dma *last_dw;
+       static char *last_bus_id;
+       int i = -1;
+
+       /*
+        * dmaengine framework calls this routine for all channels of all dma
+        * controller, until true is returned. If 'param' bus_id is not
+        * registered with a dma controller (dw), then there is no need of
+        * running below function for all channels of dw.
+        *
+        * This block of code does this by saving the parameters of last
+        * failure. If dw and param are same, i.e. trying on same dw with
+        * different channel, return false.
+        */
+       if ((last_dw == dw) && (last_bus_id == param))
+               return false;
+       /*
+        * Return true:
+        * - If dw_dma's platform data is not filled with slave info, then all
+        *   dma controllers are fine for transfer.
+        * - Or if param is NULL
+        */
+       if (!dw->sd || !param)
+               return true;
+
+       while (++i < dw->sd_count) {
+               if (!strcmp(dw->sd[i].bus_id, param)) {
+                       chan->private = &dw->sd[i];
+                       last_dw = NULL;
+                       last_bus_id = NULL;
+
+                       return true;
+               }
+       }
+
+       last_dw = dw;
+       last_bus_id = param;
+       return false;
+}
+EXPORT_SYMBOL(dw_dma_generic_filter);
+
 /* --------------------- Cyclic DMA API extensions -------------------- */
 
 /**
@@ -1299,6 +1389,11 @@ struct dw_cyclic_desc *dw_dma_cyclic_prep(struct dma_chan *chan,
 
        retval = ERR_PTR(-EINVAL);
 
+       if (unlikely(!is_slave_direction(direction)))
+               goto out_err;
+
+       dwc->direction = direction;
+
        if (direction == DMA_MEM_TO_DEV)
                reg_width = __ffs(sconfig->dst_addr_width);
        else
@@ -1313,8 +1408,6 @@ struct dw_cyclic_desc *dw_dma_cyclic_prep(struct dma_chan *chan,
                goto out_err;
        if (unlikely(buf_addr & ((1 << reg_width) - 1)))
                goto out_err;
-       if (unlikely(!(direction & (DMA_MEM_TO_DEV | DMA_DEV_TO_MEM))))
-               goto out_err;
 
        retval = ERR_PTR(-ENOMEM);
 
@@ -1372,20 +1465,14 @@ struct dw_cyclic_desc *dw_dma_cyclic_prep(struct dma_chan *chan,
                desc->lli.ctlhi = (period_len >> reg_width);
                cdesc->desc[i] = desc;
 
-               if (last) {
+               if (last)
                        last->lli.llp = desc->txd.phys;
-                       dma_sync_single_for_device(chan2parent(chan),
-                                       last->txd.phys, sizeof(last->lli),
-                                       DMA_TO_DEVICE);
-               }
 
                last = desc;
        }
 
        /* lets make a cyclic list */
        last->lli.llp = cdesc->desc[0]->txd.phys;
-       dma_sync_single_for_device(chan2parent(chan), last->txd.phys,
-                       sizeof(last->lli), DMA_TO_DEVICE);
 
        dev_dbg(chan2dev(&dwc->chan), "cyclic prepared buf 0x%llx len %zu "
                        "period %zu periods %d\n", (unsigned long long)buf_addr,
@@ -1463,6 +1550,91 @@ static void dw_dma_off(struct dw_dma *dw)
                dw->chan[i].initialized = false;
 }
 
+#ifdef CONFIG_OF
+static struct dw_dma_platform_data *
+dw_dma_parse_dt(struct platform_device *pdev)
+{
+       struct device_node *sn, *cn, *np = pdev->dev.of_node;
+       struct dw_dma_platform_data *pdata;
+       struct dw_dma_slave *sd;
+       u32 tmp, arr[4];
+
+       if (!np) {
+               dev_err(&pdev->dev, "Missing DT data\n");
+               return NULL;
+       }
+
+       pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
+       if (!pdata)
+               return NULL;
+
+       if (of_property_read_u32(np, "nr_channels", &pdata->nr_channels))
+               return NULL;
+
+       if (of_property_read_bool(np, "is_private"))
+               pdata->is_private = true;
+
+       if (!of_property_read_u32(np, "chan_allocation_order", &tmp))
+               pdata->chan_allocation_order = (unsigned char)tmp;
+
+       if (!of_property_read_u32(np, "chan_priority", &tmp))
+               pdata->chan_priority = tmp;
+
+       if (!of_property_read_u32(np, "block_size", &tmp))
+               pdata->block_size = tmp;
+
+       if (!of_property_read_u32(np, "nr_masters", &tmp)) {
+               if (tmp > 4)
+                       return NULL;
+
+               pdata->nr_masters = tmp;
+       }
+
+       if (!of_property_read_u32_array(np, "data_width", arr,
+                               pdata->nr_masters))
+               for (tmp = 0; tmp < pdata->nr_masters; tmp++)
+                       pdata->data_width[tmp] = arr[tmp];
+
+       /* parse slave data */
+       sn = of_find_node_by_name(np, "slave_info");
+       if (!sn)
+               return pdata;
+
+       /* calculate number of slaves */
+       tmp = of_get_child_count(sn);
+       if (!tmp)
+               return NULL;
+
+       sd = devm_kzalloc(&pdev->dev, sizeof(*sd) * tmp, GFP_KERNEL);
+       if (!sd)
+               return NULL;
+
+       pdata->sd = sd;
+       pdata->sd_count = tmp;
+
+       for_each_child_of_node(sn, cn) {
+               sd->dma_dev = &pdev->dev;
+               of_property_read_string(cn, "bus_id", &sd->bus_id);
+               of_property_read_u32(cn, "cfg_hi", &sd->cfg_hi);
+               of_property_read_u32(cn, "cfg_lo", &sd->cfg_lo);
+               if (!of_property_read_u32(cn, "src_master", &tmp))
+                       sd->src_master = tmp;
+
+               if (!of_property_read_u32(cn, "dst_master", &tmp))
+                       sd->dst_master = tmp;
+               sd++;
+       }
+
+       return pdata;
+}
+#else
+static inline struct dw_dma_platform_data *
+dw_dma_parse_dt(struct platform_device *pdev)
+{
+       return NULL;
+}
+#endif
+
 static int dw_probe(struct platform_device *pdev)
 {
        struct dw_dma_platform_data *pdata;
@@ -1478,10 +1650,6 @@ static int dw_probe(struct platform_device *pdev)
        int                     err;
        int                     i;
 
-       pdata = dev_get_platdata(&pdev->dev);
-       if (!pdata || pdata->nr_channels > DW_DMA_MAX_NR_CHANNELS)
-               return -EINVAL;
-
        io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        if (!io)
                return -EINVAL;
@@ -1494,9 +1662,33 @@ static int dw_probe(struct platform_device *pdev)
        if (IS_ERR(regs))
                return PTR_ERR(regs);
 
+       /* Apply default dma_mask if needed */
+       if (!pdev->dev.dma_mask) {
+               pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;
+               pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
+       }
+
        dw_params = dma_read_byaddr(regs, DW_PARAMS);
        autocfg = dw_params >> DW_PARAMS_EN & 0x1;
 
+       dev_dbg(&pdev->dev, "DW_PARAMS: 0x%08x\n", dw_params);
+
+       pdata = dev_get_platdata(&pdev->dev);
+       if (!pdata)
+               pdata = dw_dma_parse_dt(pdev);
+
+       if (!pdata && autocfg) {
+               pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
+               if (!pdata)
+                       return -ENOMEM;
+
+               /* Fill platform data with the default values */
+               pdata->is_private = true;
+               pdata->chan_allocation_order = CHAN_ALLOCATION_ASCENDING;
+               pdata->chan_priority = CHAN_PRIORITY_ASCENDING;
+       } else if (!pdata || pdata->nr_channels > DW_DMA_MAX_NR_CHANNELS)
+               return -EINVAL;
+
        if (autocfg)
                nr_channels = (dw_params >> DW_PARAMS_NR_CHAN & 0x7) + 1;
        else
@@ -1513,6 +1705,8 @@ static int dw_probe(struct platform_device *pdev)
        clk_prepare_enable(dw->clk);
 
        dw->regs = regs;
+       dw->sd = pdata->sd;
+       dw->sd_count = pdata->sd_count;
 
        /* get hardware configuration parameters */
        if (autocfg) {
@@ -1544,6 +1738,14 @@ static int dw_probe(struct platform_device *pdev)
 
        platform_set_drvdata(pdev, dw);
 
+       /* create a pool of consistent memory blocks for hardware descriptors */
+       dw->desc_pool = dmam_pool_create("dw_dmac_desc_pool", &pdev->dev,
+                                        sizeof(struct dw_desc), 4, 0);
+       if (!dw->desc_pool) {
+               dev_err(&pdev->dev, "No memory for descriptors dma pool\n");
+               return -ENOMEM;
+       }
+
        tasklet_init(&dw->tasklet, dw_dma_tasklet, (unsigned long)dw);
 
        INIT_LIST_HEAD(&dw->dma.channels);
@@ -1575,7 +1777,7 @@ static int dw_probe(struct platform_device *pdev)
 
                channel_clear_bit(dw, CH_EN, dwc->mask);
 
-               dwc->dw = dw;
+               dwc->direction = DMA_TRANS_NONE;
 
                /* hardware configuration */
                if (autocfg) {
@@ -1584,6 +1786,9 @@ static int dw_probe(struct platform_device *pdev)
                        dwc_params = dma_read_byaddr(regs + r * sizeof(u32),
                                                     DWC_PARAMS);
 
+                       dev_dbg(&pdev->dev, "DWC_PARAMS[%d]: 0x%08x\n", i,
+                                           dwc_params);
+
                        /* Decode maximum block size for given channel. The
                         * stored 4 bit value represents blocks from 0x00 for 3
                         * up to 0x0a for 4095. */
@@ -1627,8 +1832,8 @@ static int dw_probe(struct platform_device *pdev)
 
        dma_writel(dw, CFG, DW_CFG_DMA_EN);
 
-       printk(KERN_INFO "%s: DesignWare DMA Controller, %d channels\n",
-                       dev_name(&pdev->dev), nr_channels);
+       dev_info(&pdev->dev, "DesignWare DMA Controller, %d channels\n",
+                nr_channels);
 
        dma_async_device_register(&dw->dma);
 
@@ -1658,7 +1863,7 @@ static void dw_shutdown(struct platform_device *pdev)
 {
        struct dw_dma   *dw = platform_get_drvdata(pdev);
 
-       dw_dma_off(platform_get_drvdata(pdev));
+       dw_dma_off(dw);
        clk_disable_unprepare(dw->clk);
 }
 
@@ -1667,7 +1872,7 @@ static int dw_suspend_noirq(struct device *dev)
        struct platform_device *pdev = to_platform_device(dev);
        struct dw_dma   *dw = platform_get_drvdata(pdev);
 
-       dw_dma_off(platform_get_drvdata(pdev));
+       dw_dma_off(dw);
        clk_disable_unprepare(dw->clk);
 
        return 0;
@@ -1680,6 +1885,7 @@ static int dw_resume_noirq(struct device *dev)
 
        clk_prepare_enable(dw->clk);
        dma_writel(dw, CFG, DW_CFG_DMA_EN);
+
        return 0;
 }
 
@@ -1700,7 +1906,13 @@ static const struct of_device_id dw_dma_id_table[] = {
 MODULE_DEVICE_TABLE(of, dw_dma_id_table);
 #endif
 
+static const struct platform_device_id dw_dma_ids[] = {
+       { "INTL9C60", 0 },
+       { }
+};
+
 static struct platform_driver dw_driver = {
+       .probe          = dw_probe,
        .remove         = dw_remove,
        .shutdown       = dw_shutdown,
        .driver = {
@@ -1708,11 +1920,12 @@ static struct platform_driver dw_driver = {
                .pm     = &dw_dev_pm_ops,
                .of_match_table = of_match_ptr(dw_dma_id_table),
        },
+       .id_table       = dw_dma_ids,
 };
 
 static int __init dw_init(void)
 {
-       return platform_driver_probe(&dw_driver, dw_probe);
+       return platform_driver_register(&dw_driver);
 }
 subsys_initcall(dw_init);