From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752151AbbBKAZm (ORCPT ); Tue, 10 Feb 2015 19:25:42 -0500 Received: from mga02.intel.com ([134.134.136.20]:58913 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751834AbbBKAZi (ORCPT ); Tue, 10 Feb 2015 19:25:38 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.09,554,1418112000"; d="scan'208";a="664582290" Date: Tue, 10 Feb 2015 16:23:18 -0800 From: Vinod Koul To: Robert Baldyga Cc: dan.j.williams@intel.com, lars@metafoo.de, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, m.szyprowski@samsung.com, k.kozlowski@samsung.com, kyungmin.park@samsung.com, l.czerwinski@samsung.com, padma.kvr@gmail.com Subject: Re: [PATCH v3 1/2] dma: pl330: improve pl330_tx_status() function Message-ID: <20150211002318.GB21387@intel.com> References: <1418208918-28127-1-git-send-email-r.baldyga@samsung.com> <1418208918-28127-2-git-send-email-r.baldyga@samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1418208918-28127-2-git-send-email-r.baldyga@samsung.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Dec 10, 2014 at 11:55:17AM +0100, Robert Baldyga wrote: > This patch adds possibility to read residue of DMA transfer. It's useful > when we want to know how many bytes have been transferred before we > terminate channel. It can take place, for example, on timeout interrupt. > > Signed-off-by: Lukasz Czerwinski > Signed-off-by: Robert Baldyga > --- > drivers/dma/pl330.c | 68 +++++++++++++++++++++++++++++++++++++++++++++++++++-- > 1 file changed, 66 insertions(+), 2 deletions(-) > > diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c > index bdf40b5..2f4d561 100644 > --- a/drivers/dma/pl330.c > +++ b/drivers/dma/pl330.c > @@ -504,6 +504,9 @@ struct dma_pl330_desc { > > enum desc_status status; > > + int bytes_requested; > + bool last; > + > /* The channel which currently holds this desc */ > struct dma_pl330_chan *pchan; > > @@ -2182,11 +2185,68 @@ static void pl330_free_chan_resources(struct dma_chan *chan) > pm_runtime_put_autosuspend(pch->dmac->ddma.dev); > } > > +int pl330_get_current_xferred_count(struct dma_pl330_chan *pch, > + struct dma_pl330_desc *desc) > +{ > + struct pl330_thread *thrd = pch->thread; > + struct pl330_dmac *pl330 = pch->dmac; > + void __iomem *regs = thrd->dmac->base; > + u32 val, addr; > + > + pm_runtime_get_sync(pl330->ddma.dev); > + val = addr = 0; > + if (desc->rqcfg.src_inc) { > + val = readl(regs + SA(thrd->id)); > + addr = desc->px.src_addr; > + } else { > + val = readl(regs + DA(thrd->id)); > + addr = desc->px.dst_addr; > + } > + pm_runtime_mark_last_busy(pch->dmac->ddma.dev); > + pm_runtime_put_autosuspend(pl330->ddma.dev); > + return val - addr; > +} > + > static enum dma_status > pl330_tx_status(struct dma_chan *chan, dma_cookie_t cookie, > struct dma_tx_state *txstate) > { > - return dma_cookie_status(chan, cookie, txstate); > + enum dma_status ret; > + unsigned long flags; > + struct dma_pl330_desc *desc, *running = NULL; > + struct dma_pl330_chan *pch = to_pchan(chan); > + unsigned int transferred, residual = 0; > + > + spin_lock_irqsave(&pch->lock, flags); You want to check the dma_cookie_status here first and then based on status go into residue calcaultion, that too only when the txstate is NON null. -- ~Vinod > + > + if (pch->thread->req_running != -1) > + running = pch->thread->req[pch->thread->req_running].desc; > + > + /* Check in pending list */ > + list_for_each_entry(desc, &pch->work_list, node) { > + if (desc->status == DONE) > + transferred = desc->bytes_requested; > + else if (running && desc == running) > + transferred = > + pl330_get_current_xferred_count(pch, desc); > + else > + transferred = 0; > + residual += desc->bytes_requested - transferred; > + if (desc->txd.cookie == cookie) { > + dma_set_residue(txstate, residual); > + ret = desc->status; > + spin_unlock_irqrestore(&pch->lock, flags); > + return ret; > + } > + if (desc->last) > + residual = 0; > + } > + spin_unlock_irqrestore(&pch->lock, flags); > + > + ret = dma_cookie_status(chan, cookie, txstate); > + dma_set_residue(txstate, 0); > + > + return ret; > } > > static void pl330_issue_pending(struct dma_chan *chan) > @@ -2231,12 +2291,14 @@ static dma_cookie_t pl330_tx_submit(struct dma_async_tx_descriptor *tx) > desc->txd.callback = last->txd.callback; > desc->txd.callback_param = last->txd.callback_param; > } > + last->last = false; > > dma_cookie_assign(&desc->txd); > > list_move_tail(&desc->node, &pch->submitted_list); > } > > + last->last = true; > cookie = dma_cookie_assign(&last->txd); > list_add_tail(&last->node, &pch->submitted_list); > spin_unlock_irqrestore(&pch->lock, flags); > @@ -2459,6 +2521,7 @@ static struct dma_async_tx_descriptor *pl330_prep_dma_cyclic( > desc->rqtype = direction; > desc->rqcfg.brst_size = pch->burst_sz; > desc->rqcfg.brst_len = 1; > + desc->bytes_requested = period_len; > fill_px(&desc->px, dst, src, period_len); > > if (!first) > @@ -2601,6 +2664,7 @@ pl330_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, > desc->rqcfg.brst_size = pch->burst_sz; > desc->rqcfg.brst_len = 1; > desc->rqtype = direction; > + desc->bytes_requested = sg_dma_len(sg); > } > > /* Return the last desc in the chain */ > @@ -2631,7 +2695,7 @@ static int pl330_dma_device_slave_caps(struct dma_chan *dchan, > caps->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV); > caps->cmd_pause = false; > caps->cmd_terminate = true; > - caps->residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR; > + caps->residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT; > > return 0; > } > -- > 1.9.1 > --