From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:53251 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932075AbcEBTyx (ORCPT ); Mon, 2 May 2016 15:54:53 -0400 Subject: Patch "spi: rockchip: modify DMA max burst to 1" has been added to the 4.5-stable tree To: addy.ke@rock-chips.com, broonie@kernel.org, dianders@chromium.org, gregkh@linuxfoundation.org, heiko@sntech.de, olof@lixom.net, shawn.lin@rock-chips.com, sonnyrao@chromium.org, vinod.koul@intel.com, wxt@rock-chips.com Cc: , From: Date: Mon, 02 May 2016 12:54:50 -0700 Message-ID: <146221889012214@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled spi: rockchip: modify DMA max burst to 1 to the 4.5-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: spi-rockchip-modify-dma-max-burst-to-1.patch and it can be found in the queue-4.5 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 80abf8880cc6e1594c11b7c417f22dde60e25312 Mon Sep 17 00:00:00 2001 From: Addy Ke Date: Fri, 22 Jan 2016 19:06:52 +0800 Subject: spi: rockchip: modify DMA max burst to 1 From: Addy Ke commit 80abf8880cc6e1594c11b7c417f22dde60e25312 upstream. Generic dma controller on Rockchips' platform cannot support DMAFLUSHP instruction which make dma to flush the req of non-aligned or non-multiple of what we need. That will cause an unrecoverable dma bus error. The saftest way is to set dma max burst to 1. Signed-off-by: Addy ke Fixes: 64e36824b32b06 ("spi/rockchip: add driver for Rockchip...") Signed-off-by: Shawn Lin cc: Heiko Stuebner cc: Olof Johansson cc: Doug Anderson cc: Sonny Rao Acked-by: Mark Brown Signed-off-by: Caesar Wang Signed-off-by: Vinod Koul Signed-off-by: Greg Kroah-Hartman --- drivers/spi/spi-rockchip.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) --- a/drivers/spi/spi-rockchip.c +++ b/drivers/spi/spi-rockchip.c @@ -199,6 +199,7 @@ struct rockchip_spi { struct sg_table rx_sg; struct rockchip_spi_dma_data dma_rx; struct rockchip_spi_dma_data dma_tx; + struct dma_slave_caps dma_caps; }; static inline void spi_enable_chip(struct rockchip_spi *rs, int enable) @@ -454,7 +455,10 @@ static void rockchip_spi_prepare_dma(str rxconf.direction = rs->dma_rx.direction; rxconf.src_addr = rs->dma_rx.addr; rxconf.src_addr_width = rs->n_bytes; - rxconf.src_maxburst = rs->n_bytes; + if (rs->dma_caps.max_burst > 4) + rxconf.src_maxburst = 4; + else + rxconf.src_maxburst = 1; dmaengine_slave_config(rs->dma_rx.ch, &rxconf); rxdesc = dmaengine_prep_slave_sg( @@ -471,7 +475,10 @@ static void rockchip_spi_prepare_dma(str txconf.direction = rs->dma_tx.direction; txconf.dst_addr = rs->dma_tx.addr; txconf.dst_addr_width = rs->n_bytes; - txconf.dst_maxburst = rs->n_bytes; + if (rs->dma_caps.max_burst > 4) + txconf.dst_maxburst = 4; + else + txconf.dst_maxburst = 1; dmaengine_slave_config(rs->dma_tx.ch, &txconf); txdesc = dmaengine_prep_slave_sg( @@ -735,6 +742,7 @@ static int rockchip_spi_probe(struct pla } if (rs->dma_tx.ch && rs->dma_rx.ch) { + dma_get_slave_caps(rs->dma_rx.ch, &(rs->dma_caps)); rs->dma_tx.addr = (dma_addr_t)(mem->start + ROCKCHIP_SPI_TXDR); rs->dma_rx.addr = (dma_addr_t)(mem->start + ROCKCHIP_SPI_RXDR); rs->dma_tx.direction = DMA_MEM_TO_DEV; Patches currently in stable-queue which might be from addy.ke@rock-chips.com are queue-4.5/spi-rockchip-modify-dma-max-burst-to-1.patch