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Subject: Re: [RFC PATCH 0/2] mtd: spi-nor: Handle vmalloc'd buffers
To: Vignesh R <vigneshr@ti.com>, David Woodhouse <dwmw2@infradead.org>,
        Brian Norris <computersforpeace@gmail.com>,
        Boris Brezillon <boris.brezillon@free-electrons.com>,
        Marek Vasut <marek.vasut@gmail.com>,
        Richard Weinberger <richard@nod.at>,
        Cyrille Pitchen <cyrille.pitchen@atmel.com>
References: <20170227120839.16545-1-vigneshr@ti.com>
Cc: linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org,
        linux-omap@vger.kernel.org, linux-spi@vger.kernel.org
From: Frode Isaksen <fisaksen@baylibre.com>
Message-ID: <884efafc-6b34-0cb6-4c9f-e3a926114130@baylibre.com>
Date: Mon, 27 Feb 2017 15:03:57 +0100
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On 27/02/2017 13:08, Vignesh R wrote:
> This series implements bounce buffer support to handle vmalloc'd buffers
> in case of drivers use DMA, similar to what is done in MTD NAND
> framework.
>
> I have tested this on two platform:
> DRA74 SoC (cortex a15 @1GHz) with s25fl256s1 QSPI (SPI bus frequency
> 76.8 MHz) and I don't see any performance degradation with UBIFS
> read/write(10MB file).
> AM437x SoC (cortex a9 @1GHz) with macronix mx66l51235l QSPI flash (SPI bus
> frequency 48MHz) and performance degradation is <4% for UBIFS.
>
>
> Vignesh R (2):
>   mtd: spi-nor: Introduce bounce buffer to handle vmalloc'd buffers
>   mtd: devices: m25p80: Enable spi-nor bounce buffer support
>
>  drivers/mtd/devices/m25p80.c  |  1 +
>  drivers/mtd/spi-nor/spi-nor.c | 30 +++++++++++++++++++++++++++---
>  include/linux/mtd/spi-nor.h   |  4 ++++
>  3 files changed, 32 insertions(+), 3 deletions(-)
>
I have tested this on a daVinci EVM board with SPI DMA enabled and the UBIFS tests all passed.

Thanks,
Frode