diff --git a/drivers/dma/amba-pl08x.c b/drivers/dma/amba-pl08x.c index a897315261bc..202c9e2d2e9e 100644 --- a/drivers/dma/amba-pl08x.c +++ b/drivers/dma/amba-pl08x.c @@ -340,53 +340,56 @@ static inline u32 get_bytes_in_cctl(u32 cctl) static u32 pl08x_getbytes_chan(struct pl08x_dma_chan *plchan) { struct pl08x_phy_chan *ch; - struct pl08x_txd *txdi = NULL; struct pl08x_txd *txd; unsigned long flags; size_t bytes = 0; spin_lock_irqsave(&plchan->lock, flags); - ch = plchan->phychan; txd = plchan->at; /* - * Next follow the LLIs to get the number of pending bytes in the - * currently active transaction. + * Follow the LLIs to get the number of remaining + * bytes in the currently active transaction. */ if (ch && txd) { - struct pl08x_lli *llis_va = txd->llis_va; - struct pl08x_lli *llis_bus = (struct pl08x_lli *) txd->llis_bus; u32 clli = readl(ch->base + PL080_CH_LLI) & ~PL080_LLI_LM_AHB2; - /* First get the bytes in the current active LLI */ + /* First get the remaining bytes in the active transfer */ bytes = get_bytes_in_cctl(readl(ch->base + PL080_CH_CONTROL)); if (clli) { - int i = 0; + struct pl08x_lli *llis_va = txd->llis_va; + dma_addr_t llis_bus = txd->llis_bus; + int index; - /* Forward to the LLI pointed to by clli */ - while ((clli != (u32) &(llis_bus[i])) && - (i < MAX_NUM_TSFR_LLIS)) - i++; + BUG_ON(clli < llis_bus || clli >= llis_bus + + sizeof(struct pl08x_lli) * MAX_NUM_TSFR_LLIS); + + /* + * Locate the next LLI - as this is an array, + * it's simple maths to find. + */ + index = (clli - llis_bus) / sizeof(struct pl08x_lli); + + for (; index < MAX_NUM_TSFR_LLIS; index++) { + bytes += get_bytes_in_cctl(llis_va[index].cctl); - while (clli) { - bytes += get_bytes_in_cctl(llis_va[i].cctl); /* * A LLI pointer of 0 terminates the LLI list */ - clli = llis_va[i].lli; - i++; + if (!llis_va[index].lli) + break; } } } /* Sum up all queued transactions */ if (!list_empty(&plchan->desc_list)) { + struct pl08x_txd *txdi; list_for_each_entry(txdi, &plchan->desc_list, node) { bytes += txdi->len; } - } spin_unlock_irqrestore(&plchan->lock, flags);