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From:   Martin Blumenstingl <martin.blumenstingl@googlemail.com>
To:     vadivel.muruganx.ramuthevar@linux.intel.com
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Subject: RE: [PATCH v1 2/2] mtd: rawnand: Add NAND controller support on Intel LGM SoC
Date:   Thu, 16 Apr 2020 00:05:33 +0200
Message-Id: <20200415220533.733834-1-martin.blumenstingl@googlemail.com>
In-Reply-To: <20200414022433.36622-3-vadivel.muruganx.ramuthevar@linux.intel.com>
References: <20200414022433.36622-3-vadivel.muruganx.ramuthevar@linux.intel.com>
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Hi,

first of all: thank you for working on upstreaming this.
Especially since you are going to use the new exec_op style in v2 as
Boris suggested.

> From: Ramuthevar Vadivel Murugan <vadivel.muruganx.ramuthevar@linux.intel.com>
> 
> This patch adds the new IP of Nand Flash Controller(NFC) support
> on Intel's Lightning Mountain(LGM) SoC.
> 
> DMA is used for burst data transfer operation, also DMA HW supports
> aligned 32bit memory address and aligned data access by default.
> DMA burst of 8 supported. Data register used to support the read/write
> operation from/to device.
I am wondering how this new hardware is different from the Lantiq NAND
controller IP - for which there is already a driver in mainline (it's
in drivers/mtd/nand/raw/xway_nand.c).
The CON and WAIT registers look suspiciously similar.

As far as I understand the "old" SoCs (VRX200 and earlier) don't have
a built-in ECC engine. This seems to have changed with ARX300 though
(again, AFAIK).

A bit of lineage on these SoCs (initially these were developed by
Infineon. Lantiq then started as an Infineon spin-off in 2009 and
was then acquired by Intel in 2015):
- Danube
- ARX100 from 2008/2009
- VRX200 from 2009/2010
- ARX300 from 2014
- GRX350 from 2015/2016
- GRX550 from 2017
- and now finally: LGM from 2020 (est.)

The existing xway_nand driver supports the Danube, ARX100 and VRX200
SoCs.


Best regards,
Martin