From: Vinod Koul <vkoul@kernel.org>
To: Peng Ma <peng.ma@nxp.com>
Cc: robh+dt@kernel.org, shawnguo@kernel.org, mark.rutland@arm.com,
leoyang.li@nxp.com, dan.j.williams@intel.com,
dmaengine@vger.kernel.org, devicetree@vger.kernel.org,
linux-kernel@vger.kernel.org,
linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH 3/4] dmaengine: fsl-edma: support little endian for edma driver
Date: Tue, 21 May 2019 10:08:07 +0530 [thread overview]
Message-ID: <20190521043807.GN15118@vkoul-mobl> (raw)
In-Reply-To: <20190506090344.37784-3-peng.ma@nxp.com>
On 06-05-19, 09:03, Peng Ma wrote:
> improve edma driver to support little endian.
Can you explain a bit more how adding the below lines adds little endian
support...
>
> Signed-off-by: Peng Ma <peng.ma@nxp.com>
> ---
> drivers/dma/fsl-edma-common.c | 5 +++++
> 1 files changed, 5 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/dma/fsl-edma-common.c b/drivers/dma/fsl-edma-common.c
> index 680b2a0..6bf238e 100644
> --- a/drivers/dma/fsl-edma-common.c
> +++ b/drivers/dma/fsl-edma-common.c
> @@ -83,9 +83,14 @@ void fsl_edma_chan_mux(struct fsl_edma_chan *fsl_chan,
> u32 ch = fsl_chan->vchan.chan.chan_id;
> void __iomem *muxaddr;
> unsigned int chans_per_mux, ch_off;
> + int endian_diff[4] = {3, 1, -1, -3};
>
> chans_per_mux = fsl_chan->edma->n_chans / DMAMUX_NR;
> ch_off = fsl_chan->vchan.chan.chan_id % chans_per_mux;
> +
> + if (!fsl_chan->edma->big_endian)
> + ch_off += endian_diff[ch_off % 4];
> +
> muxaddr = fsl_chan->edma->muxbase[ch / chans_per_mux];
> slot = EDMAMUX_CHCFG_SOURCE(slot);
>
> --
> 1.7.1
--
~Vinod
next prev parent reply other threads:[~2019-05-21 4:38 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-05-06 9:03 [PATCH 1/4] arm64: dts: fsl: ls1028a: Add qDMA node Peng Ma
2019-05-06 9:03 ` [PATCH 2/4] arm64: dts: fsl: ls1028a: Add eDMA node Peng Ma
2019-06-18 13:13 ` Shawn Guo
2019-06-19 1:47 ` [EXT] " Peng Ma
2019-05-06 9:03 ` [PATCH 3/4] dmaengine: fsl-edma: support little endian for edma driver Peng Ma
2019-05-21 4:38 ` Vinod Koul [this message]
2019-05-22 6:33 ` [EXT] " Peng Ma
2019-05-06 9:03 ` [PATCH 4/4] dt-bindings: fsl-qdma: Add LS1028A qDMA bindings Peng Ma
2019-06-13 18:07 ` Rob Herring
2019-06-18 13:08 ` Shawn Guo
2019-06-18 13:06 ` [PATCH 1/4] arm64: dts: fsl: ls1028a: Add qDMA node Shawn Guo
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