1 files changed, 26 insertions, 12 deletions

diff --git a/drivers/dma/qcom/bam_dma.c b/drivers/dma/qcom/bam_dma.c
index d5e0a9c3ad5d..969b48176745 100644
--- a/drivers/dma/qcom/bam_dma.c
+++ b/drivers/dma/qcom/bam_dma.c
@@ -342,7 +342,7 @@ static const struct reg_offset_data bam_v1_7_reg_info[] = {
 
 #define BAM_DESC_FIFO_SIZE      SZ_32K
 #define MAX_DESCRIPTORS (BAM_DESC_FIFO_SIZE / sizeof(struct bam_desc_hw) - 1)
-#define BAM_MAX_DATA_SIZE       (SZ_32K - 8)
+#define BAM_FIFO_SIZE   (SZ_32K - 8)
 
 struct bam_chan {
         struct virt_dma_chan vc;
@@ -387,6 +387,7 @@ struct bam_device {
 
         /* execution environment ID, from DT */
         u32 ee;
+        bool controlled_remotely;
 
         const struct reg_offset_data *layout;
 
@@ -458,7 +459,7 @@ static void bam_chan_init_hw(struct bam_chan *bchan,
          */
         writel_relaxed(ALIGN(bchan->fifo_phys, sizeof(struct bam_desc_hw)),
                         bam_addr(bdev, bchan->id, BAM_P_DESC_FIFO_ADDR));
-        writel_relaxed(BAM_DESC_FIFO_SIZE,
+        writel_relaxed(BAM_FIFO_SIZE,
                         bam_addr(bdev, bchan->id, BAM_P_FIFO_SIZES));
 
         /* enable the per pipe interrupts, enable EOT, ERR, and INT irqs */
@@ -604,7 +605,7 @@ static struct dma_async_tx_descriptor *bam_prep_slave_sg(struct dma_chan *chan,
 
         /* calculate number of required entries */
         for_each_sg(sgl, sg, sg_len, i)
-                num_alloc += DIV_ROUND_UP(sg_dma_len(sg), BAM_MAX_DATA_SIZE);
+                num_alloc += DIV_ROUND_UP(sg_dma_len(sg), BAM_FIFO_SIZE);
 
         /* allocate enough room to accomodate the number of entries */
         async_desc = kzalloc(sizeof(*async_desc) +
@@ -635,10 +636,10 @@ static struct dma_async_tx_descriptor *bam_prep_slave_sg(struct dma_chan *chan,
                         desc->addr = cpu_to_le32(sg_dma_address(sg) +
                                                  curr_offset);
 
-                        if (remainder > BAM_MAX_DATA_SIZE) {
-                                desc->size = cpu_to_le16(BAM_MAX_DATA_SIZE);
-                                remainder -= BAM_MAX_DATA_SIZE;
-                                curr_offset += BAM_MAX_DATA_SIZE;
+                        if (remainder > BAM_FIFO_SIZE) {
+                                desc->size = cpu_to_le16(BAM_FIFO_SIZE);
+                                remainder -= BAM_FIFO_SIZE;
+                                curr_offset += BAM_FIFO_SIZE;
                         } else {
                                 desc->size = cpu_to_le16(remainder);
                                 remainder = 0;
@@ -801,13 +802,17 @@ static irqreturn_t bam_dma_irq(int irq, void *data)
         if (srcs & P_IRQ)
                 tasklet_schedule(&bdev->task);
 
-        if (srcs & BAM_IRQ)
+        if (srcs & BAM_IRQ) {
                 clr_mask = readl_relaxed(bam_addr(bdev, 0, BAM_IRQ_STTS));
 
-        /* don't allow reorder of the various accesses to the BAM registers */
-        mb();
+                /*
+                 * don't allow reorder of the various accesses to the BAM
+                 * registers
+                 */
+                mb();
 
-        writel_relaxed(clr_mask, bam_addr(bdev, 0, BAM_IRQ_CLR));
+                writel_relaxed(clr_mask, bam_addr(bdev, 0, BAM_IRQ_CLR));
+        }
 
         return IRQ_HANDLED;
 }
@@ -1038,6 +1043,9 @@ static int bam_init(struct bam_device *bdev)
         val = readl_relaxed(bam_addr(bdev, 0, BAM_NUM_PIPES));
         bdev->num_channels = val & BAM_NUM_PIPES_MASK;
 
+        if (bdev->controlled_remotely)
+                return 0;
+
         /* s/w reset bam */
         /* after reset all pipes are disabled and idle */
         val = readl_relaxed(bam_addr(bdev, 0, BAM_CTRL));
@@ -1125,6 +1133,9 @@ static int bam_dma_probe(struct platform_device *pdev)
                 return ret;
         }
 
+        bdev->controlled_remotely = of_property_read_bool(pdev->dev.of_node,
+                                                "qcom,controlled-remotely");
+
         bdev->bamclk = devm_clk_get(bdev->dev, "bam_clk");
         if (IS_ERR(bdev->bamclk))
                 return PTR_ERR(bdev->bamclk);
@@ -1163,7 +1174,7 @@ static int bam_dma_probe(struct platform_device *pdev)
         /* set max dma segment size */
         bdev->common.dev = bdev->dev;
         bdev->common.dev->dma_parms = &bdev->dma_parms;
-        ret = dma_set_max_seg_size(bdev->common.dev, BAM_MAX_DATA_SIZE);
+        ret = dma_set_max_seg_size(bdev->common.dev, BAM_FIFO_SIZE);
         if (ret) {
                 dev_err(bdev->dev, "cannot set maximum segment size\n");
                 goto err_bam_channel_exit;
@@ -1234,6 +1245,9 @@ static int bam_dma_remove(struct platform_device *pdev)
                 bam_dma_terminate_all(&bdev->channels[i].vc.chan);
                 tasklet_kill(&bdev->channels[i].vc.task);
 
+                if (!bdev->channels[i].fifo_virt)
+                        continue;
+
                 dma_free_wc(bdev->dev, BAM_DESC_FIFO_SIZE,
                             bdev->channels[i].fifo_virt,
                             bdev->channels[i].fifo_phys);