dmaengine: fix cyclic dma usage
[linux-flexiantxendom0-3.2.10.git] / drivers / dma / at_hdmac.c
index d774800..bf0d7e4 100644 (file)
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
 
 #include "at_hdmac_regs.h"
+#include "dmaengine.h"
 
 /*
  * Glossary
@@ -190,27 +193,6 @@ static void atc_desc_chain(struct at_desc **first, struct at_desc **prev,
 }
 
 /**
- * atc_assign_cookie - compute and assign new cookie
- * @atchan: channel we work on
- * @desc: descriptor to assign cookie for
- *
- * Called with atchan->lock held and bh disabled
- */
-static dma_cookie_t
-atc_assign_cookie(struct at_dma_chan *atchan, struct at_desc *desc)
-{
-       dma_cookie_t cookie = atchan->chan_common.cookie;
-
-       if (++cookie < 0)
-               cookie = 1;
-
-       atchan->chan_common.cookie = cookie;
-       desc->txd.cookie = cookie;
-
-       return cookie;
-}
-
-/**
  * atc_dostart - starts the DMA engine for real
  * @atchan: the channel we want to start
  * @first: first descriptor in the list we want to begin with
@@ -239,10 +221,6 @@ static void atc_dostart(struct at_dma_chan *atchan, struct at_desc *first)
 
        vdbg_dump_regs(atchan);
 
-       /* clear any pending interrupt */
-       while (dma_readl(atdma, EBCISR))
-               cpu_relax();
-
        channel_writel(atchan, SADDR, 0);
        channel_writel(atchan, DADDR, 0);
        channel_writel(atchan, CTRLA, 0);
@@ -267,7 +245,9 @@ atc_chain_complete(struct at_dma_chan *atchan, struct at_desc *desc)
        dev_vdbg(chan2dev(&atchan->chan_common),
                "descriptor %u complete\n", txd->cookie);
 
-       atchan->completed_cookie = txd->cookie;
+       /* mark the descriptor as complete for non cyclic cases only */
+       if (!atc_chan_is_cyclic(atchan))
+               dma_cookie_complete(txd);
 
        /* move children to free_list */
        list_splice_init(&desc->tx_list, &atchan->free_list);
@@ -545,7 +525,7 @@ static dma_cookie_t atc_tx_submit(struct dma_async_tx_descriptor *tx)
        unsigned long           flags;
 
        spin_lock_irqsave(&atchan->lock, flags);
-       cookie = atc_assign_cookie(atchan, desc);
+       cookie = dma_cookie_assign(tx);
 
        if (list_empty(&atchan->active_list)) {
                dev_vdbg(chan2dev(tx->chan), "tx_submit: started %u\n",
@@ -657,14 +637,16 @@ err_desc_get:
  * @sg_len: number of entries in @scatterlist
  * @direction: DMA direction
  * @flags: tx descriptor status flags
+ * @context: transaction context (ignored)
  */
 static struct dma_async_tx_descriptor *
 atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
-               unsigned int sg_len, enum dma_data_direction direction,
-               unsigned long flags)
+               unsigned int sg_len, enum dma_transfer_direction direction,
+               unsigned long flags, void *context)
 {
        struct at_dma_chan      *atchan = to_at_dma_chan(chan);
        struct at_dma_slave     *atslave = chan->private;
+       struct dma_slave_config *sconfig = &atchan->dma_sconfig;
        struct at_desc          *first = NULL;
        struct at_desc          *prev = NULL;
        u32                     ctrla;
@@ -678,7 +660,7 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
 
        dev_vdbg(chan2dev(chan), "prep_slave_sg (%d): %s f0x%lx\n",
                        sg_len,
-                       direction == DMA_TO_DEVICE ? "TO DEVICE" : "FROM DEVICE",
+                       direction == DMA_MEM_TO_DEV ? "TO DEVICE" : "FROM DEVICE",
                        flags);
 
        if (unlikely(!atslave || !sg_len)) {
@@ -686,19 +668,18 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
                return NULL;
        }
 
-       reg_width = atslave->reg_width;
-
        ctrla = ATC_DEFAULT_CTRLA | atslave->ctrla;
        ctrlb = ATC_IEN;
 
        switch (direction) {
-       case DMA_TO_DEVICE:
+       case DMA_MEM_TO_DEV:
+               reg_width = convert_buswidth(sconfig->dst_addr_width);
                ctrla |=  ATC_DST_WIDTH(reg_width);
                ctrlb |=  ATC_DST_ADDR_MODE_FIXED
                        | ATC_SRC_ADDR_MODE_INCR
                        | ATC_FC_MEM2PER
                        | ATC_SIF(AT_DMA_MEM_IF) | ATC_DIF(AT_DMA_PER_IF);
-               reg = atslave->tx_reg;
+               reg = sconfig->dst_addr;
                for_each_sg(sgl, sg, sg_len, i) {
                        struct at_desc  *desc;
                        u32             len;
@@ -725,14 +706,15 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
                        total_len += len;
                }
                break;
-       case DMA_FROM_DEVICE:
+       case DMA_DEV_TO_MEM:
+               reg_width = convert_buswidth(sconfig->src_addr_width);
                ctrla |=  ATC_SRC_WIDTH(reg_width);
                ctrlb |=  ATC_DST_ADDR_MODE_INCR
                        | ATC_SRC_ADDR_MODE_FIXED
                        | ATC_FC_PER2MEM
                        | ATC_SIF(AT_DMA_PER_IF) | ATC_DIF(AT_DMA_MEM_IF);
 
-               reg = atslave->rx_reg;
+               reg = sconfig->src_addr;
                for_each_sg(sgl, sg, sg_len, i) {
                        struct at_desc  *desc;
                        u32             len;
@@ -787,7 +769,7 @@ err_desc_get:
  */
 static int
 atc_dma_cyclic_check_values(unsigned int reg_width, dma_addr_t buf_addr,
-               size_t period_len, enum dma_data_direction direction)
+               size_t period_len, enum dma_transfer_direction direction)
 {
        if (period_len > (ATC_BTSIZE_MAX << reg_width))
                goto err_out;
@@ -795,7 +777,7 @@ atc_dma_cyclic_check_values(unsigned int reg_width, dma_addr_t buf_addr,
                goto err_out;
        if (unlikely(buf_addr & ((1 << reg_width) - 1)))
                goto err_out;
-       if (unlikely(!(direction & (DMA_TO_DEVICE | DMA_FROM_DEVICE))))
+       if (unlikely(!(direction & (DMA_DEV_TO_MEM | DMA_MEM_TO_DEV))))
                goto err_out;
 
        return 0;
@@ -808,12 +790,15 @@ err_out:
  * atc_dma_cyclic_fill_desc - Fill one period decriptor
  */
 static int
-atc_dma_cyclic_fill_desc(struct at_dma_slave *atslave, struct at_desc *desc,
+atc_dma_cyclic_fill_desc(struct dma_chan *chan, struct at_desc *desc,
                unsigned int period_index, dma_addr_t buf_addr,
-               size_t period_len, enum dma_data_direction direction)
+               unsigned int reg_width, size_t period_len,
+               enum dma_transfer_direction direction)
 {
-       u32             ctrla;
-       unsigned int    reg_width = atslave->reg_width;
+       struct at_dma_chan      *atchan = to_at_dma_chan(chan);
+       struct at_dma_slave     *atslave = chan->private;
+       struct dma_slave_config *sconfig = &atchan->dma_sconfig;
+       u32                     ctrla;
 
        /* prepare common CRTLA value */
        ctrla =   ATC_DEFAULT_CTRLA | atslave->ctrla
@@ -822,9 +807,9 @@ atc_dma_cyclic_fill_desc(struct at_dma_slave *atslave, struct at_desc *desc,
                | period_len >> reg_width;
 
        switch (direction) {
-       case DMA_TO_DEVICE:
+       case DMA_MEM_TO_DEV:
                desc->lli.saddr = buf_addr + (period_len * period_index);
-               desc->lli.daddr = atslave->tx_reg;
+               desc->lli.daddr = sconfig->dst_addr;
                desc->lli.ctrla = ctrla;
                desc->lli.ctrlb = ATC_DST_ADDR_MODE_FIXED
                                | ATC_SRC_ADDR_MODE_INCR
@@ -833,8 +818,8 @@ atc_dma_cyclic_fill_desc(struct at_dma_slave *atslave, struct at_desc *desc,
                                | ATC_DIF(AT_DMA_PER_IF);
                break;
 
-       case DMA_FROM_DEVICE:
-               desc->lli.saddr = atslave->rx_reg;
+       case DMA_DEV_TO_MEM:
+               desc->lli.saddr = sconfig->src_addr;
                desc->lli.daddr = buf_addr + (period_len * period_index);
                desc->lli.ctrla = ctrla;
                desc->lli.ctrlb = ATC_DST_ADDR_MODE_INCR
@@ -858,21 +843,25 @@ atc_dma_cyclic_fill_desc(struct at_dma_slave *atslave, struct at_desc *desc,
  * @buf_len: total number of bytes for the entire buffer
  * @period_len: number of bytes for each period
  * @direction: transfer direction, to or from device
+ * @context: transfer context (ignored)
  */
 static struct dma_async_tx_descriptor *
 atc_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len,
-               size_t period_len, enum dma_data_direction direction)
+               size_t period_len, enum dma_transfer_direction direction,
+               void *context)
 {
        struct at_dma_chan      *atchan = to_at_dma_chan(chan);
        struct at_dma_slave     *atslave = chan->private;
+       struct dma_slave_config *sconfig = &atchan->dma_sconfig;
        struct at_desc          *first = NULL;
        struct at_desc          *prev = NULL;
        unsigned long           was_cyclic;
+       unsigned int            reg_width;
        unsigned int            periods = buf_len / period_len;
        unsigned int            i;
 
        dev_vdbg(chan2dev(chan), "prep_dma_cyclic: %s buf@0x%08x - %d (%d/%d)\n",
-                       direction == DMA_TO_DEVICE ? "TO DEVICE" : "FROM DEVICE",
+                       direction == DMA_MEM_TO_DEV ? "TO DEVICE" : "FROM DEVICE",
                        buf_addr,
                        periods, buf_len, period_len);
 
@@ -887,8 +876,13 @@ atc_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len,
                return NULL;
        }
 
+       if (sconfig->direction == DMA_MEM_TO_DEV)
+               reg_width = convert_buswidth(sconfig->dst_addr_width);
+       else
+               reg_width = convert_buswidth(sconfig->src_addr_width);
+
        /* Check for too big/unaligned periods and unaligned DMA buffer */
-       if (atc_dma_cyclic_check_values(atslave->reg_width, buf_addr,
+       if (atc_dma_cyclic_check_values(reg_width, buf_addr,
                                        period_len, direction))
                goto err_out;
 
@@ -900,8 +894,8 @@ atc_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len,
                if (!desc)
                        goto err_desc_get;
 
-               if (atc_dma_cyclic_fill_desc(atslave, desc, i, buf_addr,
-                                               period_len, direction))
+               if (atc_dma_cyclic_fill_desc(chan, desc, i, buf_addr,
+                                            reg_width, period_len, direction))
                        goto err_desc_get;
 
                atc_desc_chain(&first, &prev, desc);
@@ -924,6 +918,23 @@ err_out:
        return NULL;
 }
 
+static int set_runtime_config(struct dma_chan *chan,
+                             struct dma_slave_config *sconfig)
+{
+       struct at_dma_chan      *atchan = to_at_dma_chan(chan);
+
+       /* Check if it is chan is configured for slave transfers */
+       if (!chan->private)
+               return -EINVAL;
+
+       memcpy(&atchan->dma_sconfig, sconfig, sizeof(*sconfig));
+
+       convert_burst(&atchan->dma_sconfig.src_maxburst);
+       convert_burst(&atchan->dma_sconfig.dst_maxburst);
+
+       return 0;
+}
+
 
 static int atc_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
                       unsigned long arg)
@@ -984,6 +995,8 @@ static int atc_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
                clear_bit(ATC_IS_CYCLIC, &atchan->status);
 
                spin_unlock_irqrestore(&atchan->lock, flags);
+       } else if (cmd == DMA_SLAVE_CONFIG) {
+               return set_runtime_config(chan, (struct dma_slave_config *)arg);
        } else {
                return -ENXIO;
        }
@@ -1014,26 +1027,20 @@ atc_tx_status(struct dma_chan *chan,
 
        spin_lock_irqsave(&atchan->lock, flags);
 
-       last_complete = atchan->completed_cookie;
-       last_used = chan->cookie;
-
-       ret = dma_async_is_complete(cookie, last_complete, last_used);
+       ret = dma_cookie_status(chan, cookie, txstate);
        if (ret != DMA_SUCCESS) {
                atc_cleanup_descriptors(atchan);
 
-               last_complete = atchan->completed_cookie;
-               last_used = chan->cookie;
-
-               ret = dma_async_is_complete(cookie, last_complete, last_used);
+               ret = dma_cookie_status(chan, cookie, txstate);
        }
 
+       last_complete = chan->completed_cookie;
+       last_used = chan->cookie;
+
        spin_unlock_irqrestore(&atchan->lock, flags);
 
        if (ret != DMA_SUCCESS)
-               dma_set_tx_state(txstate, last_complete, last_used,
-                       atc_first_active(atchan)->len);
-       else
-               dma_set_tx_state(txstate, last_complete, last_used, 0);
+               dma_set_residue(txstate, atc_first_active(atchan)->len);
 
        if (atc_chan_is_paused(atchan))
                ret = DMA_PAUSED;
@@ -1127,7 +1134,7 @@ static int atc_alloc_chan_resources(struct dma_chan *chan)
        spin_lock_irqsave(&atchan->lock, flags);
        atchan->descs_allocated = i;
        list_splice(&tmp_list, &atchan->free_list);
-       atchan->completed_cookie = chan->cookie = 1;
+       dma_cookie_init(chan);
        spin_unlock_irqrestore(&atchan->lock, flags);
 
        /* channel parameters */
@@ -1175,6 +1182,56 @@ static void atc_free_chan_resources(struct dma_chan *chan)
 
 /*--  Module Management  -----------------------------------------------*/
 
+/* cap_mask is a multi-u32 bitfield, fill it with proper C code. */
+static struct at_dma_platform_data at91sam9rl_config = {
+       .nr_channels = 2,
+};
+static struct at_dma_platform_data at91sam9g45_config = {
+       .nr_channels = 8,
+};
+
+#if defined(CONFIG_OF)
+static const struct of_device_id atmel_dma_dt_ids[] = {
+       {
+               .compatible = "atmel,at91sam9rl-dma",
+               .data = &at91sam9rl_config,
+       }, {
+               .compatible = "atmel,at91sam9g45-dma",
+               .data = &at91sam9g45_config,
+       }, {
+               /* sentinel */
+       }
+};
+
+MODULE_DEVICE_TABLE(of, atmel_dma_dt_ids);
+#endif
+
+static const struct platform_device_id atdma_devtypes[] = {
+       {
+               .name = "at91sam9rl_dma",
+               .driver_data = (unsigned long) &at91sam9rl_config,
+       }, {
+               .name = "at91sam9g45_dma",
+               .driver_data = (unsigned long) &at91sam9g45_config,
+       }, {
+               /* sentinel */
+       }
+};
+
+static inline struct at_dma_platform_data * __init at_dma_get_driver_data(
+                                               struct platform_device *pdev)
+{
+       if (pdev->dev.of_node) {
+               const struct of_device_id *match;
+               match = of_match_node(atmel_dma_dt_ids, pdev->dev.of_node);
+               if (match == NULL)
+                       return NULL;
+               return match->data;
+       }
+       return (struct at_dma_platform_data *)
+                       platform_get_device_id(pdev)->driver_data;
+}
+
 /**
  * at_dma_off - disable DMA controller
  * @atdma: the Atmel HDAMC device
@@ -1193,18 +1250,23 @@ static void at_dma_off(struct at_dma *atdma)
 
 static int __init at_dma_probe(struct platform_device *pdev)
 {
-       struct at_dma_platform_data *pdata;
        struct resource         *io;
        struct at_dma           *atdma;
        size_t                  size;
        int                     irq;
        int                     err;
        int                     i;
+       struct at_dma_platform_data *plat_dat;
 
-       /* get DMA Controller parameters from platform */
-       pdata = pdev->dev.platform_data;
-       if (!pdata || pdata->nr_channels > AT_DMA_MAX_NR_CHANNELS)
-               return -EINVAL;
+       /* setup platform data for each SoC */
+       dma_cap_set(DMA_MEMCPY, at91sam9rl_config.cap_mask);
+       dma_cap_set(DMA_MEMCPY, at91sam9g45_config.cap_mask);
+       dma_cap_set(DMA_SLAVE, at91sam9g45_config.cap_mask);
+
+       /* get DMA parameters from controller type */
+       plat_dat = at_dma_get_driver_data(pdev);
+       if (!plat_dat)
+               return -ENODEV;
 
        io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        if (!io)
@@ -1215,14 +1277,14 @@ static int __init at_dma_probe(struct platform_device *pdev)
                return irq;
 
        size = sizeof(struct at_dma);
-       size += pdata->nr_channels * sizeof(struct at_dma_chan);
+       size += plat_dat->nr_channels * sizeof(struct at_dma_chan);
        atdma = kzalloc(size, GFP_KERNEL);
        if (!atdma)
                return -ENOMEM;
 
-       /* discover transaction capabilites from the platform data */
-       atdma->dma_common.cap_mask = pdata->cap_mask;
-       atdma->all_chan_mask = (1 << pdata->nr_channels) - 1;
+       /* discover transaction capabilities */
+       atdma->dma_common.cap_mask = plat_dat->cap_mask;
+       atdma->all_chan_mask = (1 << plat_dat->nr_channels) - 1;
 
        size = resource_size(io);
        if (!request_mem_region(io->start, size, pdev->dev.driver->name)) {
@@ -1268,12 +1330,11 @@ static int __init at_dma_probe(struct platform_device *pdev)
 
        /* initialize channels related values */
        INIT_LIST_HEAD(&atdma->dma_common.channels);
-       for (i = 0; i < pdata->nr_channels; i++, atdma->dma_common.chancnt++) {
+       for (i = 0; i < plat_dat->nr_channels; i++) {
                struct at_dma_chan      *atchan = &atdma->chan[i];
 
                atchan->chan_common.device = &atdma->dma_common;
-               atchan->chan_common.cookie = atchan->completed_cookie = 1;
-               atchan->chan_common.chan_id = i;
+               dma_cookie_init(&atchan->chan_common);
                list_add_tail(&atchan->chan_common.device_node,
                                &atdma->dma_common.channels);
 
@@ -1287,7 +1348,7 @@ static int __init at_dma_probe(struct platform_device *pdev)
 
                tasklet_init(&atchan->tasklet, atc_tasklet,
                                (unsigned long)atchan);
-               atc_enable_irq(atchan);
+               atc_enable_chan_irq(atdma, i);
        }
 
        /* set base routines */
@@ -1301,22 +1362,20 @@ static int __init at_dma_probe(struct platform_device *pdev)
        if (dma_has_cap(DMA_MEMCPY, atdma->dma_common.cap_mask))
                atdma->dma_common.device_prep_dma_memcpy = atc_prep_dma_memcpy;
 
-       if (dma_has_cap(DMA_SLAVE, atdma->dma_common.cap_mask))
+       if (dma_has_cap(DMA_SLAVE, atdma->dma_common.cap_mask)) {
                atdma->dma_common.device_prep_slave_sg = atc_prep_slave_sg;
-
-       if (dma_has_cap(DMA_CYCLIC, atdma->dma_common.cap_mask))
+               /* controller can do slave DMA: can trigger cyclic transfers */
+               dma_cap_set(DMA_CYCLIC, atdma->dma_common.cap_mask);
                atdma->dma_common.device_prep_dma_cyclic = atc_prep_dma_cyclic;
-
-       if (dma_has_cap(DMA_SLAVE, atdma->dma_common.cap_mask) ||
-           dma_has_cap(DMA_CYCLIC, atdma->dma_common.cap_mask))
                atdma->dma_common.device_control = atc_control;
+       }
 
        dma_writel(atdma, EN, AT_DMA_ENABLE);
 
        dev_info(&pdev->dev, "Atmel AHB DMA Controller ( %s%s), %d channels\n",
          dma_has_cap(DMA_MEMCPY, atdma->dma_common.cap_mask) ? "cpy " : "",
          dma_has_cap(DMA_SLAVE, atdma->dma_common.cap_mask)  ? "slave " : "",
-         atdma->dma_common.chancnt);
+         plat_dat->nr_channels);
 
        dma_async_device_register(&atdma->dma_common);
 
@@ -1356,7 +1415,7 @@ static int __exit at_dma_remove(struct platform_device *pdev)
                struct at_dma_chan      *atchan = to_at_dma_chan(chan);
 
                /* Disable interrupts */
-               atc_disable_irq(atchan);
+               atc_disable_chan_irq(atdma, chan->chan_id);
                tasklet_disable(&atchan->tasklet);
 
                tasklet_kill(&atchan->tasklet);
@@ -1498,9 +1557,11 @@ static const struct dev_pm_ops at_dma_dev_pm_ops = {
 static struct platform_driver at_dma_driver = {
        .remove         = __exit_p(at_dma_remove),
        .shutdown       = at_dma_shutdown,
+       .id_table       = atdma_devtypes,
        .driver = {
                .name   = "at_hdmac",
                .pm     = &at_dma_dev_pm_ops,
+               .of_match_table = of_match_ptr(atmel_dma_dt_ids),
        },
 };