The DMA code in sunxi_mmc.c is broken. mmc_trans_data_by_dma() allocates the
dma descriptors on the stack, and then exits while the dma transfer is in
progress, so the dma engine is reading stack memory which at that point may
be re-used. So far we've gotten away with this by luck, but recent u-boot
changes have shifted the stack start address by 16 bytes, which combined
with dma alignment now exposes this problem.
Since we end up just busy waiting for the dma engine anyway, this commit
fixes things by simply removing the dma code, resulting in smaller bug-free
code.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Ian Campbell <ijc@hellion.org.uk>
On Mon, 2014-05-05 at 14:18 +0200, Stefan Roese wrote:
> > + case 1:
> > +#if CONFIG_MMC1_PG
> Are you sure that this is correct and shouldn't be:
>
> +#ifdef CONFIG_MMC1_PG
>
> ?
It's "correct" in so far as it works (the boards.cfg config stuff
#defines things to 1), but I think you are right that it isn't the
preferred style. But...
> A quick scan through this patch series shows that this define
> is not set at all. Perhaps its outdated? Or is it used to support
> some other sunxi SoC? Not sure, perhaps it should be removed for
> now.
...I had thought that it was to support some other board which wasn't
being upstreamed right now, so eventually useful and harmless for now,
but I've just checked and it isn't actually used by any of the boards in
u-boot-sunxi.git. So rather than fix it to use #ifdef lets drop it.
Rather than resend the entire series, here is v5.1 of this patch.
> Other than this please add my:
>
> Reviewed-by: Stefan Roese <sr@denx.de>
Thanks!
8<---------------------------------
>From 20704e35a41664de5f516ed0e02981ac06085102 Mon Sep 17 00:00:00 2001
From: Ian Campbell <ijc@hellion.org.uk>
Date: Fri, 7 Mar 2014 04:29:39 +0000
Subject: [PATCH v5.1 7/8] sunxi: mmc support
This adds support for the MMC controller on the Allwinner A20 (sun7i)
processor.
Signed-off-by: Henrik Nordstrom <henrik@henriknordstrom.net>
Signed-off-by: Luke Leighton <lkcl@lkcl.net>
Signed-off-by: Oliver Schinagl <oliver@schinagl.nl>
Signed-off-by: Wills Wang <wills.wang.open@gmail.com>
Signed-off-by: Ian Campbell <ijc@hellion.org.uk>
Reviewed-by: Marek Vasut <marex@denx.de>
Reviewed-by: Stefan Roese <sr@denx.de>
Cc: Tom Cubie <Mr.hipboi@gmail.com>
Cc: Aaron Maoye <leafy.myeh@allwinnertech.com>
Cc: Pantelis Antoniou <panto@antoniou-consulting.com>
Reviewed-by: Tom Rini <trini@ti.com>
Hans de Goede
Ian Campbell