From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757538AbZBFHLq (ORCPT ); Fri, 6 Feb 2009 02:11:46 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752893AbZBFHLS (ORCPT ); Fri, 6 Feb 2009 02:11:18 -0500 Received: from nwd2mail10.analog.com ([137.71.25.55]:1470 "EHLO nwd2mail10.analog.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752484AbZBFHLR (ORCPT ); Fri, 6 Feb 2009 02:11:17 -0500 X-IronPort-AV: E=Sophos;i="4.37,390,1231131600"; d="scan'208";a="82422006" From: Bryan Wu To: dbrownell@users.sourceforge.net, akpm@linux-foundation.org Cc: spi-devel-general@lists.sourceforge.net, linux-kernel@vger.kernel.org, Vitja Makarov , Mike Frysinger , Bryan Wu Subject: [PATCH 01/20] Blackfin SPI Driver: ensure cache coherency before doing DMA Date: Fri, 6 Feb 2009 15:12:49 +0800 Message-Id: <1233904388-5765-2-git-send-email-cooloney@kernel.org> X-Mailer: git-send-email 1.5.6.3 In-Reply-To: <1233904388-5765-1-git-send-email-cooloney@kernel.org> References: <1233904388-5765-1-git-send-email-cooloney@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Vitja Makarov flush or invalidate caches before doing DMA transfer, if needed. [Mike Frysinger : add comment to address the issue "Full duplex only works for non-DMA transfers".] Signed-off-by: Vitja Makarov Signed-off-by: Mike Frysinger Signed-off-by: Bryan Wu --- drivers/spi/spi_bfin5xx.c | 23 ++++++++++++++++++++--- 1 files changed, 20 insertions(+), 3 deletions(-) diff --git a/drivers/spi/spi_bfin5xx.c b/drivers/spi/spi_bfin5xx.c index 7fea3cf..590f975 100644 --- a/drivers/spi/spi_bfin5xx.c +++ b/drivers/spi/spi_bfin5xx.c @@ -26,6 +26,10 @@ #include #include +/* reserved_mem_dcache_on and cache friends */ +#include +#include + #define DRV_NAME "bfin-spi" #define DRV_AUTHOR "Bryan Wu, Luke Yang" #define DRV_DESC "Blackfin BF5xx on-chip SPI Controller Driver" @@ -738,9 +742,10 @@ static void pump_transfers(unsigned long data) width, transfer->len); /* - * Try to map dma buffer and do a dma transfer if - * successful use different way to r/w according to - * drv_data->cur_chip->enable_dma + * Try to map dma buffer and do a dma transfer. If successful use, + * different way to r/w according to the enable_dma settings and if + * we are not doing a full duplex transfer (since the hardware does + * not support full duplex DMA transfers). */ if (!full_duplex && drv_data->cur_chip->enable_dma && drv_data->len > 6) { @@ -795,6 +800,12 @@ static void pump_transfers(unsigned long data) /* set transfer mode, and enable SPI */ dev_dbg(&drv_data->pdev->dev, "doing DMA in.\n"); + /* invalidate caches, if needed */ + if (bfin_addr_dcachable((unsigned long) drv_data->rx)) + invalidate_dcache_range((unsigned long) drv_data->rx, + (unsigned long) (drv_data->rx + + drv_data->len)); + /* clear tx reg soformer data is not shifted out */ write_TDBR(drv_data, 0xFFFF); @@ -815,6 +826,12 @@ static void pump_transfers(unsigned long data) } else if (drv_data->tx != NULL) { dev_dbg(&drv_data->pdev->dev, "doing DMA out.\n"); + /* flush caches, if needed */ + if (bfin_addr_dcachable((unsigned long) drv_data->tx)) + flush_dcache_range((unsigned long) drv_data->tx, + (unsigned long) (drv_data->tx + + drv_data->len)); + /* start dma */ dma_enable_irq(drv_data->dma_channel); dma_config = (RESTART | dma_width | DI_EN); -- 1.5.6.3