dmaengine/dw_dmac: Don't handle block interrupts

Block interrupts give interrupt on completion of every LLI, which is actually
too much interrupts. This is just not required for current functioning of
dw_dmac.

So, just don't handle them at all.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>

1 files changed, 6 insertions, 30 deletions

diff --git a/drivers/dma/dw_dmac.c b/drivers/dma/dw_dmac.c
index f3aecb3c0343..5d7b199208d9 100644
--- a/drivers/dma/dw_dmac.c
+++ b/drivers/dma/dw_dmac.c
@@ -192,7 +192,6 @@ static void dwc_initialize(struct dw_dma_chan *dwc)
 
         /* Enable interrupts */
         channel_set_bit(dw, MASK.XFER, dwc->mask);
-        channel_set_bit(dw, MASK.BLOCK, dwc->mask);
         channel_set_bit(dw, MASK.ERROR, dwc->mask);
 
         dwc->initialized = true;
@@ -329,12 +328,6 @@ static void dwc_scan_descriptors(struct dw_dma *dw, struct dw_dma_chan *dwc)
         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
-         * valid if we decide to scan the list.
-         */
-        dma_writel(dw, CLEAR.BLOCK, dwc->mask);
         llp = channel_readl(dwc, LLP);
         status_xfer = dma_readl(dw, RAW.XFER);
 
@@ -470,17 +463,16 @@ EXPORT_SYMBOL(dw_dma_get_dst_addr);
 
 /* called with dwc->lock held and all DMAC interrupts disabled */
 static void dwc_handle_cyclic(struct dw_dma *dw, struct dw_dma_chan *dwc,
-                u32 status_block, u32 status_err, u32 status_xfer)
+                u32 status_err, u32 status_xfer)
 {
         unsigned long flags;
 
-        if (status_block & dwc->mask) {
+        if (dwc->mask) {
                 void (*callback)(void *param);
                 void *callback_param;
 
                 dev_vdbg(chan2dev(&dwc->chan), "new cyclic period llp 0x%08x\n",
                                 channel_readl(dwc, LLP));
-                dma_writel(dw, CLEAR.BLOCK, dwc->mask);
 
                 callback = dwc->cdesc->period_callback;
                 callback_param = dwc->cdesc->period_callback_param;
@@ -520,7 +512,6 @@ static void dwc_handle_cyclic(struct dw_dma *dw, struct dw_dma_chan *dwc,
                 channel_writel(dwc, CTL_LO, 0);
                 channel_writel(dwc, CTL_HI, 0);
 
-                dma_writel(dw, CLEAR.BLOCK, dwc->mask);
                 dma_writel(dw, CLEAR.ERROR, dwc->mask);
                 dma_writel(dw, CLEAR.XFER, dwc->mask);
 
@@ -537,36 +528,29 @@ static void dw_dma_tasklet(unsigned long data)
 {
         struct dw_dma *dw = (struct dw_dma *)data;
         struct dw_dma_chan *dwc;
-        u32 status_block;
         u32 status_xfer;
         u32 status_err;
         int i;
 
-        status_block = dma_readl(dw, RAW.BLOCK);
         status_xfer = dma_readl(dw, RAW.XFER);
         status_err = dma_readl(dw, RAW.ERROR);
 
-        dev_vdbg(dw->dma.dev, "tasklet: status_block=%x status_err=%x\n",
-                        status_block, status_err);
+        dev_vdbg(dw->dma.dev, "tasklet: status_err=%x\n", status_err);
 
         for (i = 0; i < dw->dma.chancnt; i++) {
                 dwc = &dw->chan[i];
                 if (test_bit(DW_DMA_IS_CYCLIC, &dwc->flags))
-                        dwc_handle_cyclic(dw, dwc, status_block, status_err,
-                                        status_xfer);
+                        dwc_handle_cyclic(dw, dwc, status_err, status_xfer);
                 else if (status_err & (1 << i))
                         dwc_handle_error(dw, dwc);
-                else if ((status_block | status_xfer) & (1 << i))
+                else if (status_xfer & (1 << i))
                         dwc_scan_descriptors(dw, dwc);
         }
 
         /*
-         * Re-enable interrupts. Block Complete interrupts are only
-         * enabled if the INT_EN bit in the descriptor is set. This
-         * will trigger a scan before the whole list is done.
+         * Re-enable interrupts.
          */
         channel_set_bit(dw, MASK.XFER, dw->all_chan_mask);
-        channel_set_bit(dw, MASK.BLOCK, dw->all_chan_mask);
         channel_set_bit(dw, MASK.ERROR, dw->all_chan_mask);
 }
 
@@ -583,7 +567,6 @@ static irqreturn_t dw_dma_interrupt(int irq, void *dev_id)
          * softirq handler.
          */
         channel_clear_bit(dw, MASK.XFER, dw->all_chan_mask);
-        channel_clear_bit(dw, MASK.BLOCK, dw->all_chan_mask);
         channel_clear_bit(dw, MASK.ERROR, dw->all_chan_mask);
 
         status = dma_readl(dw, STATUS_INT);
@@ -594,7 +577,6 @@ static irqreturn_t dw_dma_interrupt(int irq, void *dev_id)
 
                 /* Try to recover */
                 channel_clear_bit(dw, MASK.XFER, (1 << 8) - 1);
-                channel_clear_bit(dw, MASK.BLOCK, (1 << 8) - 1);
                 channel_clear_bit(dw, MASK.SRC_TRAN, (1 << 8) - 1);
                 channel_clear_bit(dw, MASK.DST_TRAN, (1 << 8) - 1);
                 channel_clear_bit(dw, MASK.ERROR, (1 << 8) - 1);
@@ -1068,7 +1050,6 @@ static void dwc_free_chan_resources(struct dma_chan *chan)
 
         /* Disable interrupts */
         channel_clear_bit(dw, MASK.XFER, dwc->mask);
-        channel_clear_bit(dw, MASK.BLOCK, dwc->mask);
         channel_clear_bit(dw, MASK.ERROR, dwc->mask);
 
         spin_unlock_irqrestore(&dwc->lock, flags);
@@ -1120,7 +1101,6 @@ int dw_dma_cyclic_start(struct dma_chan *chan)
                 return -EBUSY;
         }
 
-        dma_writel(dw, CLEAR.BLOCK, dwc->mask);
         dma_writel(dw, CLEAR.ERROR, dwc->mask);
         dma_writel(dw, CLEAR.XFER, dwc->mask);
 
@@ -1322,7 +1302,6 @@ void dw_dma_cyclic_free(struct dma_chan *chan)
         while (dma_readl(dw, CH_EN) & dwc->mask)
                 cpu_relax();
 
-        dma_writel(dw, CLEAR.BLOCK, dwc->mask);
         dma_writel(dw, CLEAR.ERROR, dwc->mask);
         dma_writel(dw, CLEAR.XFER, dwc->mask);
 
@@ -1347,7 +1326,6 @@ static void dw_dma_off(struct dw_dma *dw)
         dma_writel(dw, CFG, 0);
 
         channel_clear_bit(dw, MASK.XFER, dw->all_chan_mask);
-        channel_clear_bit(dw, MASK.BLOCK, dw->all_chan_mask);
         channel_clear_bit(dw, MASK.SRC_TRAN, dw->all_chan_mask);
         channel_clear_bit(dw, MASK.DST_TRAN, dw->all_chan_mask);
         channel_clear_bit(dw, MASK.ERROR, dw->all_chan_mask);
@@ -1449,13 +1427,11 @@ static int __init dw_probe(struct platform_device *pdev)
 
         /* Clear/disable all interrupts on all channels. */
         dma_writel(dw, CLEAR.XFER, dw->all_chan_mask);
-        dma_writel(dw, CLEAR.BLOCK, dw->all_chan_mask);
         dma_writel(dw, CLEAR.SRC_TRAN, dw->all_chan_mask);
         dma_writel(dw, CLEAR.DST_TRAN, dw->all_chan_mask);
         dma_writel(dw, CLEAR.ERROR, dw->all_chan_mask);
 
         channel_clear_bit(dw, MASK.XFER, dw->all_chan_mask);
-        channel_clear_bit(dw, MASK.BLOCK, dw->all_chan_mask);
         channel_clear_bit(dw, MASK.SRC_TRAN, dw->all_chan_mask);
         channel_clear_bit(dw, MASK.DST_TRAN, dw->all_chan_mask);
         channel_clear_bit(dw, MASK.ERROR, dw->all_chan_mask);