From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753850Ab1HAJlk (ORCPT ); Mon, 1 Aug 2011 05:41:40 -0400 Received: from eu1sys200aog104.obsmtp.com ([207.126.144.117]:47089 "EHLO eu1sys200aog104.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753551Ab1HAJjg (ORCPT ); Mon, 1 Aug 2011 05:39:36 -0400 From: Viresh Kumar To: Cc: , , , , , , , , , , , , , , , Subject: [PATCH V2 14/20] dmaengine/amba-pl08x: Add prep_single_byte_llis() routine Date: Mon, 1 Aug 2011 15:07:24 +0530 Message-ID: <9d3d9fcd8c6268b6bfc85f0d150a46e60d7fc4c5.1312190881.git.viresh.kumar@st.com> X-Mailer: git-send-email 1.7.2.2 In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Code for creating single byte llis is present at several places. Create a routine to avoid code redundancy. Also, we don't need one lli per single byte transfer, we can have single lli to do all single byte transfer. Signed-off-by: Viresh Kumar --- drivers/dma/amba-pl08x.c | 61 +++++++++++++++++++++++++--------------------- 1 files changed, 33 insertions(+), 28 deletions(-) diff --git a/drivers/dma/amba-pl08x.c b/drivers/dma/amba-pl08x.c index c29e55c..0bdf3b8 100644 --- a/drivers/dma/amba-pl08x.c +++ b/drivers/dma/amba-pl08x.c @@ -556,6 +556,14 @@ static void pl08x_fill_lli_for_desc(struct pl08x_lli_build_data *bd, bd->remainder -= len; } +static inline void prep_byte_width_lli(struct pl08x_lli_build_data *bd, + u32 *cctl, u32 len, int num_llis, size_t *total_bytes) +{ + *cctl = pl08x_cctl_bits(*cctl, 1, 1, len); + pl08x_fill_lli_for_desc(bd, num_llis, len, *cctl); + (*total_bytes) += len; +} + /* * This fills in the table of LLIs for the transfer descriptor * Note that we assume we never have to change the burst sizes @@ -567,7 +575,7 @@ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x, struct pl08x_bus_data *mbus, *sbus; struct pl08x_lli_build_data bd; int num_llis = 0; - u32 cctl; + u32 cctl, early_bytes = 0; size_t max_bytes_per_lli, total_bytes = 0; struct pl08x_lli *llis_va; @@ -616,29 +624,27 @@ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x, mbus == &bd.srcbus ? "src" : "dst", sbus == &bd.srcbus ? "src" : "dst"); - if (txd->len < mbus->buswidth) { - /* Less than a bus width available - send as single bytes */ - while (bd.remainder) { - dev_vdbg(&pl08x->adev->dev, - "%s single byte LLIs for a transfer of " - "less than a bus width (remain 0x%08x)\n", - __func__, bd.remainder); - cctl = pl08x_cctl_bits(cctl, 1, 1, 1); - pl08x_fill_lli_for_desc(&bd, num_llis++, 1, cctl); - total_bytes++; - } - } else { - /* Make one byte LLIs until master bus is aligned */ - while ((mbus->addr) % (mbus->buswidth)) { - dev_vdbg(&pl08x->adev->dev, - "%s adjustment lli for less than bus width " - "(remain 0x%08x)\n", - __func__, bd.remainder); - cctl = pl08x_cctl_bits(cctl, 1, 1, 1); - pl08x_fill_lli_for_desc(&bd, num_llis++, 1, cctl); - total_bytes++; - } + /* + * Send byte by byte for following cases + * - Less than a bus width available + * - until master bus is aligned + */ + if (bd.remainder < mbus->buswidth) + early_bytes = bd.remainder; + else if ((mbus->addr) % (mbus->buswidth)) { + early_bytes = mbus->buswidth - (mbus->addr) % (mbus->buswidth); + if ((bd.remainder - early_bytes) < mbus->buswidth) + early_bytes = bd.remainder; + } + + if (early_bytes) { + dev_vdbg(&pl08x->adev->dev, "%s byte width LLIs " + "(remain 0x%08x)\n", __func__, bd.remainder); + prep_byte_width_lli(&bd, &cctl, early_bytes, num_llis++, + &total_bytes); + } + if (bd.remainder) { /* * Master now aligned * - if slave is not then we must set its width down @@ -689,13 +695,12 @@ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x, /* * Send any odd bytes */ - while (bd.remainder) { - cctl = pl08x_cctl_bits(cctl, 1, 1, 1); + if (bd.remainder) { dev_vdbg(&pl08x->adev->dev, - "%s align with boundary, single odd byte (remain %zu)\n", + "%s align with boundary, send odd bytes (remain %zu)\n", __func__, bd.remainder); - pl08x_fill_lli_for_desc(&bd, num_llis++, 1, cctl); - total_bytes++; + prep_byte_width_lli(&bd, &cctl, bd.remainder, + num_llis++, &total_bytes); } } -- 1.7.2.2