From 223a4f4cfe93de2fce47a8f1f719cf4d0da4e3e6 Mon Sep 17 00:00:00 2001 From: Nicolas Ferre Date: Wed, 3 Apr 2019 12:23:58 +0200 Subject: dmaengine: at_xdmac: enhance channel errors handling in tasklet Complement the identification of errors with stopping the channel and dumping the descriptor that led to the error case. Signed-off-by: Nicolas Ferre Acked-by: Ludovic Desroches Signed-off-by: Vinod Koul --- drivers/dma/at_xdmac.c | 48 ++++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 42 insertions(+), 6 deletions(-) (limited to 'drivers/dma') diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c index 37a269420435..1dd7edaefbdc 100644 --- a/drivers/dma/at_xdmac.c +++ b/drivers/dma/at_xdmac.c @@ -1575,6 +1575,46 @@ static void at_xdmac_handle_cyclic(struct at_xdmac_chan *atchan) dmaengine_desc_get_callback_invoke(txd, NULL); } +static void at_xdmac_handle_error(struct at_xdmac_chan *atchan) +{ + struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device); + struct at_xdmac_desc *bad_desc; + + /* + * The descriptor currently at the head of the active list is + * broken. Since we don't have any way to report errors, we'll + * just have to scream loudly and try to continue with other + * descriptors queued (if any). + */ + if (atchan->irq_status & AT_XDMAC_CIS_RBEIS) + dev_err(chan2dev(&atchan->chan), "read bus error!!!"); + if (atchan->irq_status & AT_XDMAC_CIS_WBEIS) + dev_err(chan2dev(&atchan->chan), "write bus error!!!"); + if (atchan->irq_status & AT_XDMAC_CIS_ROIS) + dev_err(chan2dev(&atchan->chan), "request overflow error!!!"); + + spin_lock_bh(&atchan->lock); + + /* Channel must be disabled first as it's not done automatically */ + at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask); + while (at_xdmac_read(atxdmac, AT_XDMAC_GS) & atchan->mask) + cpu_relax(); + + bad_desc = list_first_entry(&atchan->xfers_list, + struct at_xdmac_desc, + xfer_node); + + spin_unlock_bh(&atchan->lock); + + /* Print bad descriptor's details if needed */ + dev_dbg(chan2dev(&atchan->chan), + "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n", + __func__, &bad_desc->lld.mbr_sa, &bad_desc->lld.mbr_da, + bad_desc->lld.mbr_ubc); + + /* Then continue with usual descriptor management */ +} + static void at_xdmac_tasklet(unsigned long data) { struct at_xdmac_chan *atchan = (struct at_xdmac_chan *)data; @@ -1594,12 +1634,8 @@ static void at_xdmac_tasklet(unsigned long data) || (atchan->irq_status & error_mask)) { struct dma_async_tx_descriptor *txd; - if (atchan->irq_status & AT_XDMAC_CIS_RBEIS) - dev_err(chan2dev(&atchan->chan), "read bus error!!!"); - if (atchan->irq_status & AT_XDMAC_CIS_WBEIS) - dev_err(chan2dev(&atchan->chan), "write bus error!!!"); - if (atchan->irq_status & AT_XDMAC_CIS_ROIS) - dev_err(chan2dev(&atchan->chan), "request overflow error!!!"); + if (atchan->irq_status & error_mask) + at_xdmac_handle_error(atchan); spin_lock(&atchan->lock); desc = list_first_entry(&atchan->xfers_list, -- cgit v1.2.3