From patchwork Mon Feb 4 19:47:03 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matt Porter X-Patchwork-Id: 2094771 Return-Path: X-Original-To: patchwork-linux-mmc@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork1.kernel.org (Postfix) with ESMTP id 525D440B0D for ; Mon, 4 Feb 2013 19:46:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754637Ab3BDTqz (ORCPT ); Mon, 4 Feb 2013 14:46:55 -0500 Received: from mail-ie0-f170.google.com ([209.85.223.170]:43058 "EHLO mail-ie0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753653Ab3BDTq1 (ORCPT ); Mon, 4 Feb 2013 14:46:27 -0500 Received: by mail-ie0-f170.google.com with SMTP id c11so6272093ieb.15 for ; Mon, 04 Feb 2013 11:46:27 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=x-received:sender:from:to:cc:subject:date:message-id:x-mailer :in-reply-to:references; bh=m15AUfxEP/7eDrkwhyKXD7ZvK1MvHPZ/XmeSOmNRfCA=; b=c7ih4JLHwV3zeh3CsqGIY6ssHOyLyHZxXrQzg1MvFloyd2vxfhZ5gRHC7G5+QReeTq 7sm+KW96l1ozDf5sMSggf9VhpcBdQwicmqPe07YI0mbwczAEZB1tr349FA0y9yp0QCCk tCR64Zw/lo/zPZUDld1XCcqCziDK12GUj7E+V1ehcB2YBwEWUhErFTHhRjJp/QFrOGir VwABiso7C2OE9ZXu9asRlUnvr3ipdsYWgA6lIArEj8XPult4NOE24Rb1rYRAD8LNpGmt DGDmrzUbXwyHGU+2O+yz9HZvt6JrgqC1CBQxEY4Ezh4ee4Q6uMPPtfdDhzPj0G6LVSAx Kvgg== X-Received: by 10.50.40.135 with SMTP id x7mr8548082igk.79.1360007187244; Mon, 04 Feb 2013 11:46:27 -0800 (PST) Received: from beef.ohporter.com (cpe-24-166-64-7.neo.res.rr.com. [24.166.64.7]) by mx.google.com with ESMTPS id ww6sm16414630igb.2.2013.02.04.11.46.25 (version=TLSv1.1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Mon, 04 Feb 2013 11:46:26 -0800 (PST) From: Matt Porter To: Vinod Koul Cc: Dan Williams , Chris Ball , Grant Likely , Linux DaVinci Kernel List , Linux Kernel Mailing List , Linux MMC List Subject: [PATCH v3 2/3] dma: edma: add device_slave_sg_caps() support Date: Mon, 4 Feb 2013 14:47:03 -0500 Message-Id: <1360007224-21735-3-git-send-email-mporter@ti.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1360007224-21735-1-git-send-email-mporter@ti.com> References: <1360007224-21735-1-git-send-email-mporter@ti.com> Sender: linux-mmc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org Implement device_slave_sg_caps(). EDMA has a finite set of PaRAM slots available for linking a multi-segment SG transfer. In order to prevent any one channel from consuming all PaRAM slots to fulfill a large SG transfer, the driver reports a static per-channel max number of SG segments it will handle. The maximum size of an SG segment is limited by the addr_width and maxburst of a given transfer request. These values are provided by the client driver and used to calculate and return the maximum segment length. Signed-off-by: Matt Porter --- drivers/dma/edma.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/drivers/dma/edma.c b/drivers/dma/edma.c index f424298..b779cee 100644 --- a/drivers/dma/edma.c +++ b/drivers/dma/edma.c @@ -72,6 +72,7 @@ struct edma_chan { dma_addr_t addr; int addr_width; int maxburst; + struct dma_slave_sg_caps sg_caps; }; struct edma_cc { @@ -463,6 +464,20 @@ static void edma_issue_pending(struct dma_chan *chan) spin_unlock_irqrestore(&echan->vchan.lock, flags); } +static struct dma_slave_sg_caps +*edma_get_slave_sg_caps(struct dma_chan *chan, + enum dma_slave_buswidth addr_width, + u32 maxburst) +{ + struct edma_chan *echan; + + echan = to_edma_chan(chan); + echan->sg_caps.max_seg_len = + (SZ_64K - 1) * addr_width * maxburst; + + return &echan->sg_caps; +} + static size_t edma_desc_size(struct edma_desc *edesc) { int i; @@ -522,6 +537,7 @@ static void __init edma_chan_init(struct edma_cc *ecc, echan->ch_num = EDMA_CTLR_CHAN(ecc->ctlr, i); echan->ecc = ecc; echan->vchan.desc_free = edma_desc_free; + echan->sg_caps.max_seg_nr = MAX_NR_SG; vchan_init(&echan->vchan, dma); @@ -538,6 +554,7 @@ static void edma_dma_init(struct edma_cc *ecc, struct dma_device *dma, dma->device_alloc_chan_resources = edma_alloc_chan_resources; dma->device_free_chan_resources = edma_free_chan_resources; dma->device_issue_pending = edma_issue_pending; + dma->device_slave_sg_caps = edma_get_slave_sg_caps; dma->device_tx_status = edma_tx_status; dma->device_control = edma_control; dma->dev = dev;