From patchwork Mon Dec 14 15:20:25 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Martin Sperl X-Patchwork-Id: 7845401 Return-Path: X-Original-To: patchwork-linux-spi@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 7044B9F32E for ; Mon, 14 Dec 2015 15:21:22 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 5C340202EC for ; Mon, 14 Dec 2015 15:21:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 14CB42034C for ; Mon, 14 Dec 2015 15:21:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752158AbbLNPUp (ORCPT ); Mon, 14 Dec 2015 10:20:45 -0500 Received: from 212-186-180-163.dynamic.surfer.at ([212.186.180.163]:39371 "EHLO cgate.sperl.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751814AbbLNPUo (ORCPT ); Mon, 14 Dec 2015 10:20:44 -0500 Received: from raspcm.intern.sperl.org (account martin@sperl.org [10.10.10.41] verified) by sperl.org (CommuniGate Pro SMTP 6.1.2) with ESMTPSA id 6361181; Mon, 14 Dec 2015 15:20:32 +0000 From: kernel@martin.sperl.org To: Mark Brown , Stephen Warren , Lee Jones , Eric Anholt , linux-spi@vger.kernel.org, linux-rpi-kernel@lists.infradead.org Cc: Martin Sperl Subject: [PATCH v3 8/8] spi: bcm2835: move to spi-core methods translate_message and can_dma Date: Mon, 14 Dec 2015 15:20:25 +0000 Message-Id: <1450106426-2277-9-git-send-email-kernel@martin.sperl.org> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1450106426-2277-1-git-send-email-kernel@martin.sperl.org> References: <1450106426-2277-1-git-send-email-kernel@martin.sperl.org> Sender: linux-spi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_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 From: Martin Sperl Remove all limitations in can_dma that inhibit the use of DMA To meet the limitiations of the HW we are now using the standardized version of spi_translate_message, that: * splits long transfers (> 60k) * aligns transfers (on 4 byte boundary) * merges transfers (for optimizations) Signed-off-by: Martin Sperl --- drivers/spi/spi-bcm2835.c | 58 +++++++++++++++------------------------------ 1 file changed, 19 insertions(+), 39 deletions(-) Changelog: V1 -> V3: move to use spi-core methods where possible -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-spi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/drivers/spi/spi-bcm2835.c b/drivers/spi/spi-bcm2835.c index cf04960..75e4425 100644 --- a/drivers/spi/spi-bcm2835.c +++ b/drivers/spi/spi-bcm2835.c @@ -361,44 +361,8 @@ static bool bcm2835_spi_can_dma(struct spi_master *master, if (!gpio_is_valid(spi->cs_gpio)) return false; - /* we start DMA efforts only on bigger transfers */ - if (tfr->len < BCM2835_SPI_DMA_MIN_LENGTH) - return false; - - /* BCM2835_SPI_DLEN has defined a max transfer size as - * 16 bit, so max is 65535 - * we can revisit this by using an alternative transfer - * method - ideally this would get done without any more - * interaction... - */ - if (tfr->len > 65535) { - dev_warn_once(&spi->dev, - "transfer size of %d too big for dma-transfer\n", - tfr->len); - return false; - } - - /* if we run rx/tx_buf with word aligned addresses then we are OK */ - if ((((size_t)tfr->rx_buf & 3) == 0) && - (((size_t)tfr->tx_buf & 3) == 0)) - return true; - - /* otherwise we only allow transfers within the same page - * to avoid wasting time on dma_mapping when it is not practical - */ - if (((size_t)tfr->tx_buf & (PAGE_SIZE - 1)) + tfr->len > PAGE_SIZE) { - dev_warn_once(&spi->dev, - "Unaligned spi tx-transfer bridging page\n"); - return false; - } - if (((size_t)tfr->rx_buf & (PAGE_SIZE - 1)) + tfr->len > PAGE_SIZE) { - dev_warn_once(&spi->dev, - "Unaligned spi rx-transfer bridging page\n"); - return false; - } - - /* return OK */ - return true; + /* use the default implementation */ + return spi_can_dma_min_dma_len(master, spi, tfr); } static void bcm2835_dma_release(struct spi_master *master) @@ -461,7 +425,23 @@ static void bcm2835_dma_init(struct spi_master *master, struct device *dev) /* all went well, so set can_dma */ master->can_dma = bcm2835_spi_can_dma; - master->max_dma_len = 65535; /* limitation by BCM2835_SPI_DLEN */ + + /* set up transform message using the default implementation + * for size, alignment and merging transfers + */ + master->translate_message = spi_translate_message_size_align_merge; + + /* the minimum length when we run DMA */ + master->min_dma_len = BCM2835_SPI_DMA_MIN_LENGTH; + + /* the max_dma_len limited by BCM2835_SPI_DLEN is actually 65535, + * but for al practical purposes we use 15 pages (60k) + */ + master->max_dma_len = 15 * PAGE_SIZE; + + /* dma alignment is 4 bytes */ + master->dma_alignment = 4; + /* need to do TX AND RX DMA, so we need dummy buffers */ master->flags = SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX;