dmaengine: imx-sdma: factor out a struct sdma_desc from struct sdma_channel

This is a preparation step to make the adding of virt-dma easier.
We create a struct sdma_desc, move some fields from struct sdma_channel
there and add a pointer from the former to the latter. For now we
allocate the data statically in struct sdma_channel, but with
virt-dma support it will be dynamically allocated.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Robin Gong <yibin.gong@nxp.com>
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Tested-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Vinod Koul <vkoul@kernel.org>

diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index f077992..19c351f 100644 (file)
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -289,6 +289,30 @@ struct sdma_context_data {
 struct sdma_engine;
 
 /**
+ * struct sdma_desc - descriptor structor for one transfer
+ * @vd                 descriptor for virt dma
+ * @num_bd             max NUM_BD. number of descriptors currently handling
+ * @buf_tail           ID of the buffer that was processed
+ * @buf_ptail          ID of the previous buffer that was processed
+ * @period_len         period length, used in cyclic.
+ * @chn_real_count     the real count updated from bd->mode.count
+ * @chn_count          the transfer count setuped
+ * @sdmac              sdma_channel pointer
+ * @bd                 pointer of alloced bd
+ */
+struct sdma_desc {
+       unsigned int            num_bd;
+       dma_addr_t              bd_phys;
+       unsigned int            buf_tail;
+       unsigned int            buf_ptail;
+       unsigned int            period_len;
+       unsigned int            chn_real_count;
+       unsigned int            chn_count;
+       struct sdma_channel     *sdmac;
+       struct sdma_buffer_descriptor *bd;
+};
+
+/**
  * struct sdma_channel - housekeeping for a SDMA channel
  *
  * @sdma               pointer to the SDMA engine for this channel
@@ -298,11 +322,10 @@ struct sdma_engine;
  * @event_id0          aka dma request line
  * @event_id1          for channels that use 2 events
  * @word_size          peripheral access size
- * @buf_tail           ID of the buffer that was processed
- * @buf_ptail          ID of the previous buffer that was processed
- * @num_bd             max NUM_BD. number of descriptors currently handling
  */
 struct sdma_channel {
+       struct sdma_desc                *desc;
+       struct sdma_desc                _desc;
        struct sdma_engine              *sdma;
        unsigned int                    channel;
        enum dma_transfer_direction             direction;
@@ -310,12 +333,6 @@ struct sdma_channel {
        unsigned int                    event_id0;
        unsigned int                    event_id1;
        enum dma_slave_buswidth         word_size;
-       unsigned int                    buf_tail;
-       unsigned int                    buf_ptail;
-       unsigned int                    num_bd;
-       unsigned int                    period_len;
-       struct sdma_buffer_descriptor   *bd;
-       dma_addr_t                      bd_phys;
        unsigned int                    pc_from_device, pc_to_device;
        unsigned int                    device_to_device;
        unsigned long                   flags;
@@ -325,10 +342,8 @@ struct sdma_channel {
        u32                             shp_addr, per_addr;
        struct dma_chan                 chan;
        spinlock_t                      lock;
-       struct dma_async_tx_descriptor  desc;
+       struct dma_async_tx_descriptor  txdesc;
        enum dma_status                 status;
-       unsigned int                    chn_count;
-       unsigned int                    chn_real_count;
        struct tasklet_struct           tasklet;
        struct imx_dma_data             data;
        bool                            enabled;
@@ -391,6 +406,8 @@ struct sdma_engine {
        u32                             spba_start_addr;
        u32                             spba_end_addr;
        unsigned int                    irq;
+       dma_addr_t                      bd0_phys;
+       struct sdma_buffer_descriptor   *bd0;
 };
 
 static struct sdma_driver_data sdma_imx31 = {
@@ -625,7 +642,7 @@ static int sdma_run_channel0(struct sdma_engine *sdma)
 static int sdma_load_script(struct sdma_engine *sdma, void *buf, int size,
                u32 address)
 {
-       struct sdma_buffer_descriptor *bd0 = sdma->channel[0].bd;
+       struct sdma_buffer_descriptor *bd0 = sdma->bd0;
        void *buf_virt;
        dma_addr_t buf_phys;
        int ret;
@@ -700,7 +717,9 @@ static void sdma_update_channel_loop(struct sdma_channel *sdmac)
         * call callback function.
         */
        while (1) {
-               bd = &sdmac->bd[sdmac->buf_tail];
+               struct sdma_desc *desc = sdmac->desc;
+
+               bd = &desc->bd[desc->buf_tail];
 
                if (bd->mode.status & BD_DONE)
                        break;
@@ -716,11 +735,11 @@ static void sdma_update_channel_loop(struct sdma_channel *sdmac)
                * the number of bytes present in the current buffer descriptor.
                */
 
-               sdmac->chn_real_count = bd->mode.count;
+               desc->chn_real_count = bd->mode.count;
                bd->mode.status |= BD_DONE;
-               bd->mode.count = sdmac->period_len;
-               sdmac->buf_ptail = sdmac->buf_tail;
-               sdmac->buf_tail = (sdmac->buf_tail + 1) % sdmac->num_bd;
+               bd->mode.count = desc->period_len;
+               desc->buf_ptail = desc->buf_tail;
+               desc->buf_tail = (desc->buf_tail + 1) % desc->num_bd;
 
                /*
                 * The callback is called from the interrupt context in order
@@ -729,7 +748,7 @@ static void sdma_update_channel_loop(struct sdma_channel *sdmac)
                 * executed.
                 */
 
-               dmaengine_desc_get_callback_invoke(&sdmac->desc, NULL);
+               dmaengine_desc_get_callback_invoke(&sdmac->txdesc, NULL);
 
                if (error)
                        sdmac->status = old_status;
@@ -742,17 +761,17 @@ static void mxc_sdma_handle_channel_normal(unsigned long data)
        struct sdma_buffer_descriptor *bd;
        int i, error = 0;
 
-       sdmac->chn_real_count = 0;
+       sdmac->desc->chn_real_count = 0;
        /*
         * non loop mode. Iterate over all descriptors, collect
         * errors and call callback function
         */
-       for (i = 0; i < sdmac->num_bd; i++) {
-               bd = &sdmac->bd[i];
+       for (i = 0; i < sdmac->desc->num_bd; i++) {
+               bd = &sdmac->desc->bd[i];
 
                 if (bd->mode.status & (BD_DONE | BD_RROR))
                        error = -EIO;
-                sdmac->chn_real_count += bd->mode.count;
+                sdmac->desc->chn_real_count += bd->mode.count;
        }
 
        if (error)
@@ -760,9 +779,9 @@ static void mxc_sdma_handle_channel_normal(unsigned long data)
        else
                sdmac->status = DMA_COMPLETE;
 
-       dma_cookie_complete(&sdmac->desc);
+       dma_cookie_complete(&sdmac->txdesc);
 
-       dmaengine_desc_get_callback_invoke(&sdmac->desc, NULL);
+       dmaengine_desc_get_callback_invoke(&sdmac->txdesc, NULL);
 }
 
 static irqreturn_t sdma_int_handler(int irq, void *dev_id)
@@ -890,7 +909,7 @@ static int sdma_load_context(struct sdma_channel *sdmac)
        int channel = sdmac->channel;
        int load_address;
        struct sdma_context_data *context = sdma->context;
-       struct sdma_buffer_descriptor *bd0 = sdma->channel[0].bd;
+       struct sdma_buffer_descriptor *bd0 = sdma->bd0;
        int ret;
        unsigned long flags;
 
@@ -1093,18 +1112,22 @@ static int sdma_set_channel_priority(struct sdma_channel *sdmac,
 static int sdma_request_channel(struct sdma_channel *sdmac)
 {
        struct sdma_engine *sdma = sdmac->sdma;
+       struct sdma_desc *desc;
        int channel = sdmac->channel;
        int ret = -EBUSY;
 
-       sdmac->bd = dma_zalloc_coherent(NULL, PAGE_SIZE, &sdmac->bd_phys,
+       sdmac->desc = &sdmac->_desc;
+       desc = sdmac->desc;
+
+       desc->bd = dma_zalloc_coherent(NULL, PAGE_SIZE, &desc->bd_phys,
                                        GFP_KERNEL);
-       if (!sdmac->bd) {
+       if (!desc->bd) {
                ret = -ENOMEM;
                goto out;
        }
 
-       sdma->channel_control[channel].base_bd_ptr = sdmac->bd_phys;
-       sdma->channel_control[channel].current_bd_ptr = sdmac->bd_phys;
+       sdma->channel_control[channel].base_bd_ptr = desc->bd_phys;
+       sdma->channel_control[channel].current_bd_ptr = desc->bd_phys;
 
        sdma_set_channel_priority(sdmac, MXC_SDMA_DEFAULT_PRIORITY);
        return 0;
@@ -1169,10 +1192,10 @@ static int sdma_alloc_chan_resources(struct dma_chan *chan)
        if (ret)
                goto disable_clk_ahb;
 
-       dma_async_tx_descriptor_init(&sdmac->desc, chan);
-       sdmac->desc.tx_submit = sdma_tx_submit;
+       dma_async_tx_descriptor_init(&sdmac->txdesc, chan);
+       sdmac->txdesc.tx_submit = sdma_tx_submit;
        /* txd.flags will be overwritten in prep funcs */
-       sdmac->desc.flags = DMA_CTRL_ACK;
+       sdmac->txdesc.flags = DMA_CTRL_ACK;
 
        return 0;
 
@@ -1187,6 +1210,7 @@ static void sdma_free_chan_resources(struct dma_chan *chan)
 {
        struct sdma_channel *sdmac = to_sdma_chan(chan);
        struct sdma_engine *sdma = sdmac->sdma;
+       struct sdma_desc *desc = sdmac->desc;
 
        sdma_disable_channel(chan);
 
@@ -1200,7 +1224,7 @@ static void sdma_free_chan_resources(struct dma_chan *chan)
 
        sdma_set_channel_priority(sdmac, 0);
 
-       dma_free_coherent(NULL, PAGE_SIZE, sdmac->bd, sdmac->bd_phys);
+       dma_free_coherent(NULL, PAGE_SIZE, desc->bd, desc->bd_phys);
 
        clk_disable(sdma->clk_ipg);
        clk_disable(sdma->clk_ahb);
@@ -1216,6 +1240,7 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
        int ret, i, count;
        int channel = sdmac->channel;
        struct scatterlist *sg;
+       struct sdma_desc *desc = sdmac->desc;
 
        if (sdmac->status == DMA_IN_PROGRESS)
                return NULL;
@@ -1223,9 +1248,9 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
 
        sdmac->flags = 0;
 
-       sdmac->buf_tail = 0;
-       sdmac->buf_ptail = 0;
-       sdmac->chn_real_count = 0;
+       desc->buf_tail = 0;
+       desc->buf_ptail = 0;
+       desc->chn_real_count = 0;
 
        dev_dbg(sdma->dev, "setting up %d entries for channel %d.\n",
                        sg_len, channel);
@@ -1242,9 +1267,9 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
                goto err_out;
        }
 
-       sdmac->chn_count = 0;
+       desc->chn_count = 0;
        for_each_sg(sgl, sg, sg_len, i) {
-               struct sdma_buffer_descriptor *bd = &sdmac->bd[i];
+               struct sdma_buffer_descriptor *bd = &desc->bd[i];
                int param;
 
                bd->buffer_addr = sg->dma_address;
@@ -1259,7 +1284,7 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
                }
 
                bd->mode.count = count;
-               sdmac->chn_count += count;
+               desc->chn_count += count;
 
                if (sdmac->word_size > DMA_SLAVE_BUSWIDTH_4_BYTES) {
                        ret =  -EINVAL;
@@ -1300,10 +1325,10 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
                bd->mode.status = param;
        }
 
-       sdmac->num_bd = sg_len;
-       sdma->channel_control[channel].current_bd_ptr = sdmac->bd_phys;
+       desc->num_bd = sg_len;
+       sdma->channel_control[channel].current_bd_ptr = desc->bd_phys;
 
-       return &sdmac->desc;
+       return &sdmac->txdesc;
 err_out:
        sdmac->status = DMA_ERROR;
        return NULL;
@@ -1319,6 +1344,7 @@ static struct dma_async_tx_descriptor *sdma_prep_dma_cyclic(
        int num_periods = buf_len / period_len;
        int channel = sdmac->channel;
        int ret, i = 0, buf = 0;
+       struct sdma_desc *desc = sdmac->desc;
 
        dev_dbg(sdma->dev, "%s channel: %d\n", __func__, channel);
 
@@ -1327,10 +1353,10 @@ static struct dma_async_tx_descriptor *sdma_prep_dma_cyclic(
 
        sdmac->status = DMA_IN_PROGRESS;
 
-       sdmac->buf_tail = 0;
-       sdmac->buf_ptail = 0;
-       sdmac->chn_real_count = 0;
-       sdmac->period_len = period_len;
+       desc->buf_tail = 0;
+       desc->buf_ptail = 0;
+       desc->chn_real_count = 0;
+       desc->period_len = period_len;
 
        sdmac->flags |= IMX_DMA_SG_LOOP;
        sdmac->direction = direction;
@@ -1351,7 +1377,7 @@ static struct dma_async_tx_descriptor *sdma_prep_dma_cyclic(
        }
 
        while (buf < buf_len) {
-               struct sdma_buffer_descriptor *bd = &sdmac->bd[i];
+               struct sdma_buffer_descriptor *bd = &desc->bd[i];
                int param;
 
                bd->buffer_addr = dma_addr;
@@ -1382,10 +1408,10 @@ static struct dma_async_tx_descriptor *sdma_prep_dma_cyclic(
                i++;
        }
 
-       sdmac->num_bd = num_periods;
-       sdma->channel_control[channel].current_bd_ptr = sdmac->bd_phys;
+       desc->num_bd = num_periods;
+       sdma->channel_control[channel].current_bd_ptr = desc->bd_phys;
 
-       return &sdmac->desc;
+       return &sdmac->txdesc;
 err_out:
        sdmac->status = DMA_ERROR;
        return NULL;
@@ -1424,13 +1450,14 @@ static enum dma_status sdma_tx_status(struct dma_chan *chan,
                                      struct dma_tx_state *txstate)
 {
        struct sdma_channel *sdmac = to_sdma_chan(chan);
+       struct sdma_desc *desc = sdmac->desc;
        u32 residue;
 
        if (sdmac->flags & IMX_DMA_SG_LOOP)
-               residue = (sdmac->num_bd - sdmac->buf_ptail) *
-                          sdmac->period_len - sdmac->chn_real_count;
+               residue = (desc->num_bd - desc->buf_ptail) *
+                          desc->period_len - desc->chn_real_count;
        else
-               residue = sdmac->chn_count - sdmac->chn_real_count;
+               residue = desc->chn_count - desc->chn_real_count;
 
        dma_set_tx_state(txstate, chan->completed_cookie, chan->cookie,
                         residue);
@@ -1654,6 +1681,8 @@ static int sdma_init(struct sdma_engine *sdma)
        if (ret)
                goto err_dma_alloc;
 
+       sdma->bd0 = sdma->channel[0].desc->bd;
+
        sdma_config_ownership(&sdma->channel[0], false, true, false);
 
        /* Set Command Channel (Channel Zero) */