From patchwork Sun Jul 21 06:57:56 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joel Fernandes X-Patchwork-Id: 2830879 Return-Path: X-Original-To: patchwork-linux-mmc@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 4D57F9F4D4 for ; Sun, 21 Jul 2013 06:59:10 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 65B6D20172 for ; Sun, 21 Jul 2013 06:59:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7388920170 for ; Sun, 21 Jul 2013 06:59:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753510Ab3GUG7A (ORCPT ); Sun, 21 Jul 2013 02:59:00 -0400 Received: from arroyo.ext.ti.com ([192.94.94.40]:39520 "EHLO arroyo.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753347Ab3GUG6j (ORCPT ); Sun, 21 Jul 2013 02:58:39 -0400 Received: from dlelxv90.itg.ti.com ([172.17.2.17]) by arroyo.ext.ti.com (8.13.7/8.13.7) with ESMTP id r6L6w0nV011263; Sun, 21 Jul 2013 01:58:00 -0500 Received: from DLEE70.ent.ti.com (dlee70.ent.ti.com [157.170.170.113]) by dlelxv90.itg.ti.com (8.14.3/8.13.8) with ESMTP id r6L6w0J0031003; Sun, 21 Jul 2013 01:58:00 -0500 Received: from dlelxv22.itg.ti.com (172.17.1.197) by DLEE70.ent.ti.com (157.170.170.113) with Microsoft SMTP Server id 14.2.342.3; Sun, 21 Jul 2013 01:58:00 -0500 Received: from joel-laptop.itg.ti.com (h56-25.vpn.ti.com [172.24.56.25]) by dlelxv22.itg.ti.com (8.13.8/8.13.8) with ESMTP id r6L6vuQl011266; Sun, 21 Jul 2013 01:57:59 -0500 From: Joel Fernandes To: Tony Lindgren , Sekhar Nori , Santosh Shilimkar , Sricharan R , Rajendra Nayak , Lokesh Vutla , Matt Porter , Grant Likely , Rob Herring , Vinod Koul , Dan Williams , Mark Brown , Benoit Cousson , Russell King , Arnd Bergmann , Balaji TK , Gururaja Hebbar , Chris Ball , Jason Kridner CC: Linux OMAP List , Linux ARM Kernel List , Linux DaVinci Kernel List , Linux Kernel Mailing List , Linux MMC List , Joel Fernandes Subject: [RFC 1/5] dma: edma: Setup parameters to DMA MAX_SG_NR at a time Date: Sun, 21 Jul 2013 01:57:56 -0500 Message-ID: <1374389876-32500-1-git-send-email-joelf@ti.com> X-Mailer: git-send-email 1.7.9.5 MIME-Version: 1.0 Sender: linux-mmc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org X-Spam-Status: No, score=-8.3 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Changes are made here for configuring existing parameters to support DMA'ing them out in batches as needed. Also allocate as many as slots as needed by the SG list, but not more than MAX_SG_NR. Then these slots will be reused accordingly. For ex, if MAX_SG_NR=10, and number of SG entries is 40, still only 10 slots will be allocated to DMA the entire SG list of size 40. Also enable TC interrupts for slots that are a last in a current iteration, or that fall on a MAX_SG_NR boundary. Signed-off-by: Joel Fernandes --- drivers/dma/edma.c | 21 ++++++++++++++++++--- 1 file changed, 18 insertions(+), 3 deletions(-) diff --git a/drivers/dma/edma.c b/drivers/dma/edma.c index 083ecff..9b9954e 100644 --- a/drivers/dma/edma.c +++ b/drivers/dma/edma.c @@ -223,9 +223,11 @@ static struct dma_async_tx_descriptor *edma_prep_slave_sg( enum dma_slave_buswidth dev_width; u32 burst; struct scatterlist *sg; - int i; + int acnt, bcnt, ccnt, src, dst, cidx; int src_bidx, dst_bidx, src_cidx, dst_cidx; + int i, ret; + int num_slots_needed; if (unlikely(!echan || !sgl || !sg_len)) return NULL; @@ -257,8 +259,11 @@ static struct dma_async_tx_descriptor *edma_prep_slave_sg( edesc->pset_nr = sg_len; - for_each_sg(sgl, sg, sg_len, i) { - /* Allocate a PaRAM slot, if needed */ + /* Allocate a PaRAM slot, if needed */ + + num_slots_needed = sg_len > MAX_NR_SG ? MAX_NR_SG : sg_len; + + for (i = 0; i < num_slots_needed; i++) { if (echan->slot[i] < 0) { echan->slot[i] = edma_alloc_slot(EDMA_CTLR(echan->ch_num), @@ -268,6 +273,10 @@ static struct dma_async_tx_descriptor *edma_prep_slave_sg( return NULL; } } + } + + /* Configure PaRAM sets for each SG */ + for_each_sg(sgl, sg, sg_len, i) { acnt = dev_width; @@ -325,6 +334,12 @@ static struct dma_async_tx_descriptor *edma_prep_slave_sg( /* Configure A or AB synchronized transfers */ if (edesc->absync) edesc->pset[i].opt |= SYNCDIM; + + /* If this is the last in a current SG set of transactions, + enable interrupts so that next set is processed */ + if (!((i+1) % MAX_NR_SG)) + edesc->pset[i].opt |= TCINTEN; + /* If this is the last set, enable completion interrupt flag */ if (i == sg_len - 1) edesc->pset[i].opt |= TCINTEN;