[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <20151120211452.GB9555@codeaurora.org>
Date: Fri, 20 Nov 2015 13:14:52 -0800
From: Stephen Boyd <sboyd@...eaurora.org>
To: Mike Turquette <mturquette@...libre.com>
Cc: linux-kernel@...r.kernel.org, linux-clk@...r.kernel.org,
linux-arm-msm@...r.kernel.org, Simon Arlott <simon@...e.lp0.eu>,
Mark Brown <broonie@...nel.org>
Subject: Re: [PATCH] clk: qcom: Specify LE device endianness
On 11/09, Stephen Boyd wrote:
> All these clock controllers are little endian devices, but so far
> we've been relying on the regmap mmio bus handling this for us
> without explicitly stating that fact. After commit 4a98da2164cf
> (regmap-mmio: Use native endianness for read/write, 2015-10-29),
> the regmap mmio bus will read/write with the __raw_*() IO
> accessors, instead of using the readl/writel() APIs that do
> proper byte swapping for little endian devices.
>
> So if we're running on a big endian processor and haven't
> specified the endianness explicitly in the regmap config or in
> DT, we're going to switch from doing little endian byte swapping
> to big endian accesses without byte swapping, leading to some
> confusing results. On my apq8074 dragonboard, this causes the
> device to fail to boot as we access the clock controller with
> big endian IO accesses even though the device is little endian.
>
> Specify the endianness explicitly so that the regmap core
> properly byte swaps the accesses for us.
>
> Reported-by: Kevin Hilman <khilman@...aro.org>
> Cc: Simon Arlott <simon@...e.lp0.eu>
> Cc: Mark Brown <broonie@...nel.org>
> Signed-off-by: Stephen Boyd <sboyd@...eaurora.org>
> ---
Applied to clk-next
--
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists