rapidio/tsi721_dma: fix hardware error handling

Add DMA channel re-initialization after an error to avoid termination of
all pending transfer requests.

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Reported-by: Barry Wood <barry.wood@idt.com>
Tested-by: Barry Wood <barry.wood@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: Andre van Herk <andre.van.herk@prodrive-technologies.com>
Cc: Barry Wood <barry.wood@idt.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/rapidio/devices/tsi721_dma.c b/drivers/rapidio/devices/tsi721_dma.c
index 03637330c4826dc12a4bb0fdc56688155ce7064f..155cae1e62de8a6e85de2a5e874438e55083f52b 100644 (file)
--- a/drivers/rapidio/devices/tsi721_dma.c
+++ b/drivers/rapidio/devices/tsi721_dma.c
@@ -282,7 +282,7 @@ void tsi721_bdma_handler(struct tsi721_bdma_chan *bdma_chan)
        /* Disable BDMA channel interrupts */
        iowrite32(0, bdma_chan->regs + TSI721_DMAC_INTE);
        if (bdma_chan->active)
-               tasklet_schedule(&bdma_chan->tasklet);
+               tasklet_hi_schedule(&bdma_chan->tasklet);
 }
 
 #ifdef CONFIG_PCI_MSI
@@ -298,7 +298,7 @@ static irqreturn_t tsi721_bdma_msix(int irq, void *ptr)
        struct tsi721_bdma_chan *bdma_chan = ptr;
 
        if (bdma_chan->active)
-               tasklet_schedule(&bdma_chan->tasklet);
+               tasklet_hi_schedule(&bdma_chan->tasklet);
        return IRQ_HANDLED;
 }
 #endif /* CONFIG_PCI_MSI */
@@ -584,13 +584,71 @@ static void tsi721_dma_tasklet(unsigned long data)
        iowrite32(dmac_int, bdma_chan->regs + TSI721_DMAC_INT);
 
        if (dmac_int & TSI721_DMAC_INT_ERR) {
+               int i = 10000;
+               struct tsi721_tx_desc *desc;
+
+               desc = bdma_chan->active_tx;
                dmac_sts = ioread32(bdma_chan->regs + TSI721_DMAC_STS);
                tsi_err(&bdma_chan->dchan.dev->device,
-                       "ERR - DMAC%d_STS = 0x%x",
-                       bdma_chan->id, dmac_sts);
+                       "DMAC%d_STS = 0x%x did=%d raddr=0x%llx",
+                       bdma_chan->id, dmac_sts, desc->destid, desc->rio_addr);
+
+               /* Re-initialize DMA channel if possible */
+
+               if ((dmac_sts & TSI721_DMAC_STS_ABORT) == 0)
+                       goto err_out;
+
+               tsi721_clr_stat(bdma_chan);
 
                spin_lock(&bdma_chan->lock);
+
+               /* Put DMA channel into init state */
+               iowrite32(TSI721_DMAC_CTL_INIT,
+                         bdma_chan->regs + TSI721_DMAC_CTL);
+               do {
+                       udelay(1);
+                       dmac_sts = ioread32(bdma_chan->regs + TSI721_DMAC_STS);
+                       i--;
+               } while ((dmac_sts & TSI721_DMAC_STS_ABORT) && i);
+
+               if (dmac_sts & TSI721_DMAC_STS_ABORT) {
+                       tsi_err(&bdma_chan->dchan.dev->device,
+                               "Failed to re-initiate DMAC%d", bdma_chan->id);
+                       spin_unlock(&bdma_chan->lock);
+                       goto err_out;
+               }
+
+               /* Setup DMA descriptor pointers */
+               iowrite32(((u64)bdma_chan->bd_phys >> 32),
+                       bdma_chan->regs + TSI721_DMAC_DPTRH);
+               iowrite32(((u64)bdma_chan->bd_phys & TSI721_DMAC_DPTRL_MASK),
+                       bdma_chan->regs + TSI721_DMAC_DPTRL);
+
+               /* Setup descriptor status FIFO */
+               iowrite32(((u64)bdma_chan->sts_phys >> 32),
+                       bdma_chan->regs + TSI721_DMAC_DSBH);
+               iowrite32(((u64)bdma_chan->sts_phys & TSI721_DMAC_DSBL_MASK),
+                       bdma_chan->regs + TSI721_DMAC_DSBL);
+               iowrite32(TSI721_DMAC_DSSZ_SIZE(bdma_chan->sts_size),
+                       bdma_chan->regs + TSI721_DMAC_DSSZ);
+
+               /* Clear interrupt bits */
+               iowrite32(TSI721_DMAC_INT_ALL,
+                       bdma_chan->regs + TSI721_DMAC_INT);
+
+               ioread32(bdma_chan->regs + TSI721_DMAC_INT);
+
+               bdma_chan->wr_count = bdma_chan->wr_count_next = 0;
+               bdma_chan->sts_rdptr = 0;
+               udelay(10);
+
+               desc = bdma_chan->active_tx;
+               desc->status = DMA_ERROR;
+               dma_cookie_complete(&desc->txd);
+               list_add(&desc->desc_node, &bdma_chan->free_list);
                bdma_chan->active_tx = NULL;
+               if (bdma_chan->active)
+                       tsi721_advance_work(bdma_chan, NULL);
                spin_unlock(&bdma_chan->lock);
        }
 
@@ -619,16 +677,19 @@ static void tsi721_dma_tasklet(unsigned long data)
                        }
                        list_add(&desc->desc_node, &bdma_chan->free_list);
                        bdma_chan->active_tx = NULL;
-                       tsi721_advance_work(bdma_chan, NULL);
+                       if (bdma_chan->active)
+                               tsi721_advance_work(bdma_chan, NULL);
                        spin_unlock(&bdma_chan->lock);
                        if (callback)
                                callback(param);
                } else {
-                       tsi721_advance_work(bdma_chan, bdma_chan->active_tx);
+                       if (bdma_chan->active)
+                               tsi721_advance_work(bdma_chan,
+                                                   bdma_chan->active_tx);
                        spin_unlock(&bdma_chan->lock);
                }
        }
-
+err_out:
        /* Re-Enable BDMA channel interrupts */
        iowrite32(TSI721_DMAC_INT_ALL, bdma_chan->regs + TSI721_DMAC_INTE);
 }
@@ -841,7 +902,6 @@ static int tsi721_terminate_all(struct dma_chan *dchan)
 {
        struct tsi721_bdma_chan *bdma_chan = to_tsi721_chan(dchan);
        struct tsi721_tx_desc *desc, *_d;
-       u32 dmac_int;
        LIST_HEAD(list);
 
        tsi_debug(DMA, &dchan->dev->device, "DMAC%d", bdma_chan->id);
@@ -850,7 +910,10 @@ static int tsi721_terminate_all(struct dma_chan *dchan)
 
        bdma_chan->active = false;
 
-       if (!tsi721_dma_is_idle(bdma_chan)) {
+       while (!tsi721_dma_is_idle(bdma_chan)) {
+
+               udelay(5);
+#if (0)
                /* make sure to stop the transfer */
                iowrite32(TSI721_DMAC_CTL_SUSP,
                          bdma_chan->regs + TSI721_DMAC_CTL);
@@ -859,6 +922,7 @@ static int tsi721_terminate_all(struct dma_chan *dchan)
                do {
                        dmac_int = ioread32(bdma_chan->regs + TSI721_DMAC_INT);
                } while ((dmac_int & TSI721_DMAC_INT_SUSP) == 0);
+#endif
        }
 
        if (bdma_chan->active_tx)