From mboxrd@z Thu Jan 1 00:00:00 1970 From: olof@lixom.net (Olof Johansson) Date: Sat, 18 Jun 2016 22:21:13 -0700 Subject: [PATCH v4.7-rc] ARM: dts: STi: stih407-family: Disable reserved-memory co-processor nodes In-Reply-To: <1466163858-13819-1-git-send-email-maxime.coquelin@st.com> References: <1466163858-13819-1-git-send-email-maxime.coquelin@st.com> Message-ID: <20160619052113.GB11958@localhost> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Fri, Jun 17, 2016 at 01:44:18PM +0200, Maxime Coquelin wrote: > From: Lee Jones > > This patch fixes a non-booting issue in Mainline. > > When booting with a compressed kernel, we need to be careful how we > populate memory close to DDR start. AUTO_ZRELADDR is enabled by default > in multi-arch enabled configurations, which place some restrictions on > where the kernel is placed and where it will be uncompressed to on boot. > > AUTO_ZRELADDR takes the decompressor code's start address and masks out > the bottom 28 bits to obtain an address to uncompress the kernel to > (thus a load address of 0x42000000 means that the kernel will be > uncompressed to 0x40000000 i.e. DDR START on this platform). > > Even changing the load address to after the co-processor's shared memory > won't render a booting platform, since the AUTO_ZRELADDR algorithm still > ensures the kernel is uncompressed into memory shared with the first > co-processor (0x40000000). > > Another option would be to move loading to 0x4A000000, since this will > mean the decompressor will decompress the kernel to 0x48000000. However, > this would mean a large chunk (0x44000000 => 0x48000000 (64MB)) of > memory would essentially be wasted for no good reason. > > Until we can work with ST to find a suitable memory location to > relocate co-processor shared memory, let's disable the shared memory > nodes. This will ensure a working platform in the mean time. > > NB: The more observant of you will notice that we're leaving the DMU > shared memory node enabled; this is because a) it is the only one in > active use at the time of this writing and b) it is not affected by > the current default behaviour which is causing issues. > > Fixes: fe135c6 (ARM: dts: STiH407: Move over to using the 'reserved-memory' API for obtaining DMA memory) > Signed-off-by: Lee Jones > Reviewed-by Peter Griffin > Signed-off-by: Maxime Coquelin Applied, thanks. -Olof