]> git.karo-electronics.de Git - karo-tx-linux.git/blobdiff - drivers/dma/dw_dmac.c
Merge git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-fixes
[karo-tx-linux.git] / drivers / dma / dw_dmac.c
index a9755e3dd60320270535f2a57bc46341cc82c8d0..4d180ca9a1d86a46e311b25b568e99380c1399a6 100644 (file)
@@ -3,6 +3,7 @@
  * AVR32 systems.)
  *
  * Copyright (C) 2007-2008 Atmel Corporation
+ * Copyright (C) 2010-2011 ST Microelectronics
  *
  * 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
@@ -93,8 +94,9 @@ static struct dw_desc *dwc_desc_get(struct dw_dma_chan *dwc)
        struct dw_desc *desc, *_desc;
        struct dw_desc *ret = NULL;
        unsigned int i = 0;
+       unsigned long flags;
 
-       spin_lock_bh(&dwc->lock);
+       spin_lock_irqsave(&dwc->lock, flags);
        list_for_each_entry_safe(desc, _desc, &dwc->free_list, desc_node) {
                if (async_tx_test_ack(&desc->txd)) {
                        list_del(&desc->desc_node);
@@ -104,7 +106,7 @@ static struct dw_desc *dwc_desc_get(struct dw_dma_chan *dwc)
                dev_dbg(chan2dev(&dwc->chan), "desc %p not ACKed\n", desc);
                i++;
        }
-       spin_unlock_bh(&dwc->lock);
+       spin_unlock_irqrestore(&dwc->lock, flags);
 
        dev_vdbg(chan2dev(&dwc->chan), "scanned %u descriptors on freelist\n", i);
 
@@ -130,12 +132,14 @@ static void dwc_sync_desc_for_cpu(struct dw_dma_chan *dwc, struct dw_desc *desc)
  */
 static void dwc_desc_put(struct dw_dma_chan *dwc, struct dw_desc *desc)
 {
+       unsigned long flags;
+
        if (desc) {
                struct dw_desc *child;
 
                dwc_sync_desc_for_cpu(dwc, desc);
 
-               spin_lock_bh(&dwc->lock);
+               spin_lock_irqsave(&dwc->lock, flags);
                list_for_each_entry(child, &desc->tx_list, desc_node)
                        dev_vdbg(chan2dev(&dwc->chan),
                                        "moving child desc %p to freelist\n",
@@ -143,7 +147,7 @@ static void dwc_desc_put(struct dw_dma_chan *dwc, struct dw_desc *desc)
                list_splice_init(&desc->tx_list, &dwc->free_list);
                dev_vdbg(chan2dev(&dwc->chan), "moving desc %p to freelist\n", desc);
                list_add(&desc->desc_node, &dwc->free_list);
-               spin_unlock_bh(&dwc->lock);
+               spin_unlock_irqrestore(&dwc->lock, flags);
        }
 }
 
@@ -202,9 +206,11 @@ dwc_descriptor_complete(struct dw_dma_chan *dwc, struct dw_desc *desc,
        void                            *param = NULL;
        struct dma_async_tx_descriptor  *txd = &desc->txd;
        struct dw_desc                  *child;
+       unsigned long                   flags;
 
        dev_vdbg(chan2dev(&dwc->chan), "descriptor %u complete\n", txd->cookie);
 
+       spin_lock_irqsave(&dwc->lock, flags);
        dwc->completed = txd->cookie;
        if (callback_required) {
                callback = txd->callback;
@@ -241,6 +247,8 @@ dwc_descriptor_complete(struct dw_dma_chan *dwc, struct dw_desc *desc,
                }
        }
 
+       spin_unlock_irqrestore(&dwc->lock, flags);
+
        if (callback_required && callback)
                callback(param);
 }
@@ -249,7 +257,9 @@ static void dwc_complete_all(struct dw_dma *dw, struct dw_dma_chan *dwc)
 {
        struct dw_desc *desc, *_desc;
        LIST_HEAD(list);
+       unsigned long flags;
 
+       spin_lock_irqsave(&dwc->lock, flags);
        if (dma_readl(dw, CH_EN) & dwc->mask) {
                dev_err(chan2dev(&dwc->chan),
                        "BUG: XFER bit set, but channel not idle!\n");
@@ -270,6 +280,8 @@ static void dwc_complete_all(struct dw_dma *dw, struct dw_dma_chan *dwc)
                dwc_dostart(dwc, dwc_first_active(dwc));
        }
 
+       spin_unlock_irqrestore(&dwc->lock, flags);
+
        list_for_each_entry_safe(desc, _desc, &list, desc_node)
                dwc_descriptor_complete(dwc, desc, true);
 }
@@ -280,7 +292,9 @@ static void dwc_scan_descriptors(struct dw_dma *dw, struct dw_dma_chan *dwc)
        struct dw_desc *desc, *_desc;
        struct dw_desc *child;
        u32 status_xfer;
+       unsigned long flags;
 
+       spin_lock_irqsave(&dwc->lock, flags);
        /*
         * Clear block interrupt flag before scanning so that we don't
         * miss any, and read LLP before RAW_XFER to ensure it is
@@ -293,35 +307,47 @@ 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);
+               spin_unlock_irqrestore(&dwc->lock, flags);
+
                dwc_complete_all(dw, dwc);
                return;
        }
 
-       if (list_empty(&dwc->active_list))
+       if (list_empty(&dwc->active_list)) {
+               spin_unlock_irqrestore(&dwc->lock, flags);
                return;
+       }
 
        dev_vdbg(chan2dev(&dwc->chan), "scan_descriptors: llp=0x%x\n", llp);
 
        list_for_each_entry_safe(desc, _desc, &dwc->active_list, desc_node) {
                /* check first descriptors addr */
-               if (desc->txd.phys == llp)
+               if (desc->txd.phys == llp) {
+                       spin_unlock_irqrestore(&dwc->lock, flags);
                        return;
+               }
 
                /* check first descriptors llp */
-               if (desc->lli.llp == llp)
+               if (desc->lli.llp == llp) {
                        /* This one is currently in progress */
+                       spin_unlock_irqrestore(&dwc->lock, flags);
                        return;
+               }
 
                list_for_each_entry(child, &desc->tx_list, desc_node)
-                       if (child->lli.llp == llp)
+                       if (child->lli.llp == llp) {
                                /* Currently in progress */
+                               spin_unlock_irqrestore(&dwc->lock, flags);
                                return;
+                       }
 
                /*
                 * No descriptors so far seem to be in progress, i.e.
                 * this one must be done.
                 */
+               spin_unlock_irqrestore(&dwc->lock, flags);
                dwc_descriptor_complete(dwc, desc, true);
+               spin_lock_irqsave(&dwc->lock, flags);
        }
 
        dev_err(chan2dev(&dwc->chan),
@@ -336,6 +362,7 @@ static void dwc_scan_descriptors(struct dw_dma *dw, struct dw_dma_chan *dwc)
                list_move(dwc->queue.next, &dwc->active_list);
                dwc_dostart(dwc, dwc_first_active(dwc));
        }
+       spin_unlock_irqrestore(&dwc->lock, flags);
 }
 
 static void dwc_dump_lli(struct dw_dma_chan *dwc, struct dw_lli *lli)
@@ -350,9 +377,12 @@ static void dwc_handle_error(struct dw_dma *dw, struct dw_dma_chan *dwc)
 {
        struct dw_desc *bad_desc;
        struct dw_desc *child;
+       unsigned long flags;
 
        dwc_scan_descriptors(dw, dwc);
 
+       spin_lock_irqsave(&dwc->lock, flags);
+
        /*
         * The descriptor currently at the head of the active list is
         * borked. Since we don't have any way to report errors, we'll
@@ -382,6 +412,8 @@ static void dwc_handle_error(struct dw_dma *dw, struct dw_dma_chan *dwc)
        list_for_each_entry(child, &bad_desc->tx_list, desc_node)
                dwc_dump_lli(dwc, &child->lli);
 
+       spin_unlock_irqrestore(&dwc->lock, flags);
+
        /* Pretend the descriptor completed successfully */
        dwc_descriptor_complete(dwc, bad_desc, true);
 }
@@ -406,6 +438,8 @@ EXPORT_SYMBOL(dw_dma_get_dst_addr);
 static void dwc_handle_cyclic(struct dw_dma *dw, struct dw_dma_chan *dwc,
                u32 status_block, u32 status_err, u32 status_xfer)
 {
+       unsigned long flags;
+
        if (status_block & dwc->mask) {
                void (*callback)(void *param);
                void *callback_param;
@@ -416,11 +450,9 @@ static void dwc_handle_cyclic(struct dw_dma *dw, struct dw_dma_chan *dwc,
 
                callback = dwc->cdesc->period_callback;
                callback_param = dwc->cdesc->period_callback_param;
-               if (callback) {
-                       spin_unlock(&dwc->lock);
+
+               if (callback)
                        callback(callback_param);
-                       spin_lock(&dwc->lock);
-               }
        }
 
        /*
@@ -434,6 +466,9 @@ static void dwc_handle_cyclic(struct dw_dma *dw, struct dw_dma_chan *dwc,
                dev_err(chan2dev(&dwc->chan), "cyclic DMA unexpected %s "
                                "interrupt, stopping DMA transfer\n",
                                status_xfer ? "xfer" : "error");
+
+               spin_lock_irqsave(&dwc->lock, flags);
+
                dev_err(chan2dev(&dwc->chan),
                        "  SAR: 0x%x DAR: 0x%x LLP: 0x%x CTL: 0x%x:%08x\n",
                        channel_readl(dwc, SAR),
@@ -457,6 +492,8 @@ static void dwc_handle_cyclic(struct dw_dma *dw, struct dw_dma_chan *dwc,
 
                for (i = 0; i < dwc->cdesc->periods; i++)
                        dwc_dump_lli(dwc, &dwc->cdesc->desc[i]->lli);
+
+               spin_unlock_irqrestore(&dwc->lock, flags);
        }
 }
 
@@ -480,7 +517,6 @@ static void dw_dma_tasklet(unsigned long data)
 
        for (i = 0; i < dw->dma.chancnt; i++) {
                dwc = &dw->chan[i];
-               spin_lock(&dwc->lock);
                if (test_bit(DW_DMA_IS_CYCLIC, &dwc->flags))
                        dwc_handle_cyclic(dw, dwc, status_block, status_err,
                                        status_xfer);
@@ -488,7 +524,6 @@ static void dw_dma_tasklet(unsigned long data)
                        dwc_handle_error(dw, dwc);
                else if ((status_block | status_xfer) & (1 << i))
                        dwc_scan_descriptors(dw, dwc);
-               spin_unlock(&dwc->lock);
        }
 
        /*
@@ -543,8 +578,9 @@ static dma_cookie_t dwc_tx_submit(struct dma_async_tx_descriptor *tx)
        struct dw_desc          *desc = txd_to_dw_desc(tx);
        struct dw_dma_chan      *dwc = to_dw_dma_chan(tx->chan);
        dma_cookie_t            cookie;
+       unsigned long           flags;
 
-       spin_lock_bh(&dwc->lock);
+       spin_lock_irqsave(&dwc->lock, flags);
        cookie = dwc_assign_cookie(dwc, desc);
 
        /*
@@ -564,7 +600,7 @@ static dma_cookie_t dwc_tx_submit(struct dma_async_tx_descriptor *tx)
                list_add_tail(&desc->desc_node, &dwc->queue);
        }
 
-       spin_unlock_bh(&dwc->lock);
+       spin_unlock_irqrestore(&dwc->lock, flags);
 
        return cookie;
 }
@@ -826,34 +862,51 @@ static int dwc_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
        struct dw_dma_chan      *dwc = to_dw_dma_chan(chan);
        struct dw_dma           *dw = to_dw_dma(chan->device);
        struct dw_desc          *desc, *_desc;
+       unsigned long           flags;
+       u32                     cfglo;
        LIST_HEAD(list);
 
-       /* Only supports DMA_TERMINATE_ALL */
-       if (cmd != DMA_TERMINATE_ALL)
-               return -ENXIO;
+       if (cmd == DMA_PAUSE) {
+               spin_lock_irqsave(&dwc->lock, flags);
 
-       /*
-        * This is only called when something went wrong elsewhere, so
-        * we don't really care about the data. Just disable the
-        * channel. We still have to poll the channel enable bit due
-        * to AHB/HSB limitations.
-        */
-       spin_lock_bh(&dwc->lock);
+               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();
 
-       channel_clear_bit(dw, CH_EN, dwc->mask);
+               dwc->paused = true;
+               spin_unlock_irqrestore(&dwc->lock, flags);
+       } else if (cmd == DMA_RESUME) {
+               if (!dwc->paused)
+                       return 0;
 
-       while (dma_readl(dw, CH_EN) & dwc->mask)
-               cpu_relax();
+               spin_lock_irqsave(&dwc->lock, flags);
 
-       /* active_list entries will end up before queued entries */
-       list_splice_init(&dwc->queue, &list);
-       list_splice_init(&dwc->active_list, &list);
+               cfglo = channel_readl(dwc, CFG_LO);
+               channel_writel(dwc, CFG_LO, cfglo & ~DWC_CFGL_CH_SUSP);
+               dwc->paused = false;
 
-       spin_unlock_bh(&dwc->lock);
+               spin_unlock_irqrestore(&dwc->lock, flags);
+       } else if (cmd == DMA_TERMINATE_ALL) {
+               spin_lock_irqsave(&dwc->lock, flags);
 
-       /* Flush all pending and queued descriptors */
-       list_for_each_entry_safe(desc, _desc, &list, desc_node)
-               dwc_descriptor_complete(dwc, desc, false);
+               channel_clear_bit(dw, CH_EN, dwc->mask);
+               while (dma_readl(dw, CH_EN) & dwc->mask)
+                       cpu_relax();
+
+               dwc->paused = false;
+
+               /* active_list entries will end up before queued entries */
+               list_splice_init(&dwc->queue, &list);
+               list_splice_init(&dwc->active_list, &list);
+
+               spin_unlock_irqrestore(&dwc->lock, flags);
+
+               /* Flush all pending and queued descriptors */
+               list_for_each_entry_safe(desc, _desc, &list, desc_node)
+                       dwc_descriptor_complete(dwc, desc, false);
+       } else
+               return -ENXIO;
 
        return 0;
 }
@@ -873,9 +926,7 @@ dwc_tx_status(struct dma_chan *chan,
 
        ret = dma_async_is_complete(cookie, last_complete, last_used);
        if (ret != DMA_SUCCESS) {
-               spin_lock_bh(&dwc->lock);
                dwc_scan_descriptors(to_dw_dma(chan->device), dwc);
-               spin_unlock_bh(&dwc->lock);
 
                last_complete = dwc->completed;
                last_used = chan->cookie;
@@ -889,6 +940,9 @@ dwc_tx_status(struct dma_chan *chan,
        else
                dma_set_tx_state(txstate, last_complete, last_used, 0);
 
+       if (dwc->paused)
+               return DMA_PAUSED;
+
        return ret;
 }
 
@@ -896,10 +950,8 @@ static void dwc_issue_pending(struct dma_chan *chan)
 {
        struct dw_dma_chan      *dwc = to_dw_dma_chan(chan);
 
-       spin_lock_bh(&dwc->lock);
        if (!list_empty(&dwc->queue))
                dwc_scan_descriptors(to_dw_dma(chan->device), dwc);
-       spin_unlock_bh(&dwc->lock);
 }
 
 static int dwc_alloc_chan_resources(struct dma_chan *chan)
@@ -911,6 +963,7 @@ static int dwc_alloc_chan_resources(struct dma_chan *chan)
        int                     i;
        u32                     cfghi;
        u32                     cfglo;
+       unsigned long           flags;
 
        dev_vdbg(chan2dev(chan), "alloc_chan_resources\n");
 
@@ -948,16 +1001,16 @@ static int dwc_alloc_chan_resources(struct dma_chan *chan)
         * doesn't mean what you think it means), and status writeback.
         */
 
-       spin_lock_bh(&dwc->lock);
+       spin_lock_irqsave(&dwc->lock, flags);
        i = dwc->descs_allocated;
        while (dwc->descs_allocated < NR_DESCS_PER_CHANNEL) {
-               spin_unlock_bh(&dwc->lock);
+               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_bh(&dwc->lock);
+                       spin_lock_irqsave(&dwc->lock, flags);
                        break;
                }
 
@@ -969,7 +1022,7 @@ static int dwc_alloc_chan_resources(struct dma_chan *chan)
                                sizeof(desc->lli), DMA_TO_DEVICE);
                dwc_desc_put(dwc, desc);
 
-               spin_lock_bh(&dwc->lock);
+               spin_lock_irqsave(&dwc->lock, flags);
                i = ++dwc->descs_allocated;
        }
 
@@ -978,7 +1031,7 @@ static int dwc_alloc_chan_resources(struct dma_chan *chan)
        channel_set_bit(dw, MASK.BLOCK, dwc->mask);
        channel_set_bit(dw, MASK.ERROR, dwc->mask);
 
-       spin_unlock_bh(&dwc->lock);
+       spin_unlock_irqrestore(&dwc->lock, flags);
 
        dev_dbg(chan2dev(chan),
                "alloc_chan_resources allocated %d descriptors\n", i);
@@ -991,6 +1044,7 @@ static void dwc_free_chan_resources(struct dma_chan *chan)
        struct dw_dma_chan      *dwc = to_dw_dma_chan(chan);
        struct dw_dma           *dw = to_dw_dma(chan->device);
        struct dw_desc          *desc, *_desc;
+       unsigned long           flags;
        LIST_HEAD(list);
 
        dev_dbg(chan2dev(chan), "free_chan_resources (descs allocated=%u)\n",
@@ -1001,7 +1055,7 @@ static void dwc_free_chan_resources(struct dma_chan *chan)
        BUG_ON(!list_empty(&dwc->queue));
        BUG_ON(dma_readl(to_dw_dma(chan->device), CH_EN) & dwc->mask);
 
-       spin_lock_bh(&dwc->lock);
+       spin_lock_irqsave(&dwc->lock, flags);
        list_splice_init(&dwc->free_list, &list);
        dwc->descs_allocated = 0;
 
@@ -1010,7 +1064,7 @@ static void dwc_free_chan_resources(struct dma_chan *chan)
        channel_clear_bit(dw, MASK.BLOCK, dwc->mask);
        channel_clear_bit(dw, MASK.ERROR, dwc->mask);
 
-       spin_unlock_bh(&dwc->lock);
+       spin_unlock_irqrestore(&dwc->lock, flags);
 
        list_for_each_entry_safe(desc, _desc, &list, desc_node) {
                dev_vdbg(chan2dev(chan), "  freeing descriptor %p\n", desc);
@@ -1035,13 +1089,14 @@ int dw_dma_cyclic_start(struct dma_chan *chan)
 {
        struct dw_dma_chan      *dwc = to_dw_dma_chan(chan);
        struct dw_dma           *dw = to_dw_dma(dwc->chan.device);
+       unsigned long           flags;
 
        if (!test_bit(DW_DMA_IS_CYCLIC, &dwc->flags)) {
                dev_err(chan2dev(&dwc->chan), "missing prep for cyclic DMA\n");
                return -ENODEV;
        }
 
-       spin_lock(&dwc->lock);
+       spin_lock_irqsave(&dwc->lock, flags);
 
        /* assert channel is idle */
        if (dma_readl(dw, CH_EN) & dwc->mask) {
@@ -1054,7 +1109,7 @@ int dw_dma_cyclic_start(struct dma_chan *chan)
                        channel_readl(dwc, LLP),
                        channel_readl(dwc, CTL_HI),
                        channel_readl(dwc, CTL_LO));
-               spin_unlock(&dwc->lock);
+               spin_unlock_irqrestore(&dwc->lock, flags);
                return -EBUSY;
        }
 
@@ -1069,7 +1124,7 @@ int dw_dma_cyclic_start(struct dma_chan *chan)
 
        channel_set_bit(dw, CH_EN, dwc->mask);
 
-       spin_unlock(&dwc->lock);
+       spin_unlock_irqrestore(&dwc->lock, flags);
 
        return 0;
 }
@@ -1085,14 +1140,15 @@ void dw_dma_cyclic_stop(struct dma_chan *chan)
 {
        struct dw_dma_chan      *dwc = to_dw_dma_chan(chan);
        struct dw_dma           *dw = to_dw_dma(dwc->chan.device);
+       unsigned long           flags;
 
-       spin_lock(&dwc->lock);
+       spin_lock_irqsave(&dwc->lock, flags);
 
        channel_clear_bit(dw, CH_EN, dwc->mask);
        while (dma_readl(dw, CH_EN) & dwc->mask)
                cpu_relax();
 
-       spin_unlock(&dwc->lock);
+       spin_unlock_irqrestore(&dwc->lock, flags);
 }
 EXPORT_SYMBOL(dw_dma_cyclic_stop);
 
@@ -1121,17 +1177,18 @@ struct dw_cyclic_desc *dw_dma_cyclic_prep(struct dma_chan *chan,
        unsigned int                    reg_width;
        unsigned int                    periods;
        unsigned int                    i;
+       unsigned long                   flags;
 
-       spin_lock_bh(&dwc->lock);
+       spin_lock_irqsave(&dwc->lock, flags);
        if (!list_empty(&dwc->queue) || !list_empty(&dwc->active_list)) {
-               spin_unlock_bh(&dwc->lock);
+               spin_unlock_irqrestore(&dwc->lock, flags);
                dev_dbg(chan2dev(&dwc->chan),
                                "queue and/or active list are not empty\n");
                return ERR_PTR(-EBUSY);
        }
 
        was_cyclic = test_and_set_bit(DW_DMA_IS_CYCLIC, &dwc->flags);
-       spin_unlock_bh(&dwc->lock);
+       spin_unlock_irqrestore(&dwc->lock, flags);
        if (was_cyclic) {
                dev_dbg(chan2dev(&dwc->chan),
                                "channel already prepared for cyclic DMA\n");
@@ -1245,13 +1302,14 @@ void dw_dma_cyclic_free(struct dma_chan *chan)
        struct dw_dma           *dw = to_dw_dma(dwc->chan.device);
        struct dw_cyclic_desc   *cdesc = dwc->cdesc;
        int                     i;
+       unsigned long           flags;
 
        dev_dbg(chan2dev(&dwc->chan), "cyclic free\n");
 
        if (!cdesc)
                return;
 
-       spin_lock_bh(&dwc->lock);
+       spin_lock_irqsave(&dwc->lock, flags);
 
        channel_clear_bit(dw, CH_EN, dwc->mask);
        while (dma_readl(dw, CH_EN) & dwc->mask)
@@ -1261,7 +1319,7 @@ void dw_dma_cyclic_free(struct dma_chan *chan)
        dma_writel(dw, CLEAR.ERROR, dwc->mask);
        dma_writel(dw, CLEAR.XFER, dwc->mask);
 
-       spin_unlock_bh(&dwc->lock);
+       spin_unlock_irqrestore(&dwc->lock, flags);
 
        for (i = 0; i < cdesc->periods; i++)
                dwc_desc_put(dwc, cdesc->desc[i]);
@@ -1517,4 +1575,5 @@ module_exit(dw_exit);
 
 MODULE_LICENSE("GPL v2");
 MODULE_DESCRIPTION("Synopsys DesignWare DMA Controller driver");
-MODULE_AUTHOR("Haavard Skinnemoen <haavard.skinnemoen@atmel.com>");
+MODULE_AUTHOR("Haavard Skinnemoen (Atmel)");
+MODULE_AUTHOR("Viresh Kumar <viresh.kumar@st.com>");