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Date: Fri, 8 Jan 2016 14:01:00 +0000 (GMT)
From: "Maciej W. Rozycki" <macro@linux-mips.org>
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Subject: Re: [PATCH] mtd: bcm47xxsflash: use devm_ioremap_nocache() instead
 of KSEG0ADDR()
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On Fri, 8 Jan 2016, Rafał Miłecki wrote:

> > This removes some (implicit) MIPS dependencies and makes the code more
> > portable, whether we need it or not :)
> 
> So now we have following forwardtrace:
> devm_ioremap_nocache
> ioremap_nocache
> __ioremap_mode
> __ioremap
> CKSEG1ADDR
> 
> It results in different address than KSEG0ADDR:
> [    1.339752] [bcm47xxsflash_bcma_probe] KSEG0ADDR(BCMA_SOC_FLASH2):9c000000
> [    1.346848] [bcm47xxsflash_bcma_probe] devm_ioremap_nocache:bc000000
> 
> But it still works as expected! :)
> [    1.609426] 6 bcm47xxpart partitions found on MTD device bcm47xxsflash
> [    1.616169] Creating 6 MTD partitions on "bcm47xxsflash":

 It is a functional change though and I think the change from a cached to 
uncached mapping (i.e. from `ioremap' to `ioremap_nocache') has to be a 
separate patch, so that both changes can be reviewed independently.

  Maciej