Anomaly 05000480 on BF537 rev 0.0, 0.1, 0.2:
Multiple Simultaneous Urgent DMA Requests May Cause DMA System Instability
Suggested Workaround:
Program the DMA Traffic Control Period to a non-zero value. This forces
the DMA block to group accesses together rather than allow arbitration for
each piece of data placed on the internal DMA bus.
Signed-off-by: Steven Miao <realmz6@gmail.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
The BF54x lacks dedicated DMA channels for the UART peripherals and need
to be muxed between others. So add a kconfig option so people can select
which channels the UARTs will use so they can pick between SPORTs and the
less commonly used EPPI/PIXC peripherals.
Signed-off-by: steven miao <realmz6@gmail.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
The dma_memcpy() function takes care of flushing different caches for us.
Normally this is what we want, but when resuming from mem, we don't yet
have caches enabled. If these functions happen to be placed into L1 mem
(which is what we're trying to relocate), then things aren't going to
work. So define a non-cache dma_memcpy() variant to utilize in situations
like this.
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
The DMA channel status field was encoding redundant info wrt the DMA MMR
config register, and it was doing an incomplete job of checking all DMA
channels (some drivers write directly to the config register). So drop
the tristate field in favor of a binary atomic field. This simplifies
the code in general, removes the implicit need for sleeping, and forces
the suspend code to handle all channels properly.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Some Blackfin on-chip ROMs utilize some MDMA channels during the suspend
and resume process, but don't clean up after themselves. So manually
clear all DMA channels when resuming since no DMA could have been running
at this point in time. Now Linux should be able to work regardless of any
laziness on the part of the on-chip ROM or boot loader.
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Bill Gatliff & David Brownell pointed out we were missing some
copyrights, and licensing terms in some of the files in
./arch/blackfin, so this fixes things, and cleans them up.
It also removes:
- verbose GPL text(refer to the top level ./COPYING file)
- file names (you are looking at the file)
- bug url (it's in the ./MAINTAINERS file)
- "or later" on GPL-2, when we did not have that right
It also allows some Blackfin-specific assembly files to be under a BSD
like license (for people to use them outside of Linux).
Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Check whether index is within bounds before testing the element.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Allow hardware errors to be caught during early portions of booting, and
leave something in the shadow console that people can use to debug their
system with (to be printed out by the bootloader on next reset).
This enables the hardare error interrupts in head.S, allowing us to find
hardware errors when they happen (well, as much as you can with a hardware
error) and prints out the trace if it is enabled. This will catch errors
(like booting the wrong image on a 533) which previously resulted in a
infinite loop/hang, as well as random hardware errors before before
setup_arch().
To disable this debug only feature - turn off EARLY_PRINTK.
Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
The early logic to locate a free DMA channel and then set it up was broken
in a few ways that only manifested itself when we needed to set up more
than 2 on chip SRAM regions (most board defaults setup 1 or 2). First, we
checked the wrong status register (the destination gets updated, not the
source) and second, we did the ssync before rather than after resetting a
DMA config register.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Add a reminder note to avoid the DMA_DONE bit in our DMA core code.
Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Our early L1 relocate code may implicitly call code which lives in L1
memory. This is due to the dma_memcpy() rewrite that made the DMA code
lockless and safe to be used by multiple processes. If we start the
early DMA memcpy to relocate things into L1 instruction but then our
DMA memcpy code calls a function that lives in L1, things fall apart.
As such, create a small dedicated DMA memcpy routine that we can assume
sanity at boot time.
Reported-by: Filip Van Rillaer <filip.vanrillaer@oneaccess-net.com>
Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Dmacopy failed in BF537-STAMP when copy from SRAM to SDRAM and kernel
will reboot automatically.
Fixing by doing a SSYNC before mucking with DMA registers
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
push cache flushing up to dma_memcpy() so that we call the flush
functions just once
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
move most dma functions into static inlines since they are vastly 1
liners that get/set a value in a structure
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
set_dma_callback: do not store .irq if request_irq() failed so we dont
turn around and attempt to free_irq() it later on in free_dma()
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
- unify all dma in/out functions (takes ~35 lines of code now)
- unify dma_memcpy with dma in/out functions (1 place that touches MDMA0
registers)
- add support for 32bit transfers
- cleanup dma_memcpy code to be much more readable
- irqs are disabled only while programming MDMA registers rather than
the entire transaction
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Check pointers in safe_dma_memcpy as this is the entry point for user-space code
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Add irq to struct dma_channel lookup channel2irq() only once,
since channel2irq() is fairly large on some Blackfin derivatives.
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Enable: PM_SUSPEND_MEM -> Blackfin Hibernate to SDRAM
This feature requires a special bootloader (u-boot)
supporting return from hibernate.
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
IMDMA does not operate to full speed for 600MHz and higher devices
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
- add platform device resources in board files
- add new bfin_sir.h to each machines
Signed-off-by: Graf Yang <graf.yang@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
The DMA base registers are available in a global named "base_addr" for
every Blackfin variant. Give this a more descriptive name, and remove
duplicate tables from some drivers.
Signed-off-by: Bernd Schmidt <bernds_cb1@t-online.de>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
- flush/inv the correct range
- dmacopy test failed when policy is write_back - invalidate before dma
http://blackfin.uclinux.org/gf/project/uclinux-dist/tracker/?action=TrackerItemEdit&tracker_item_id=3367
It's the cache invalidate what is causing the issue.
There is no invalidate only instruction it's always: FLUSHINV
So when we "invalidate" after the DMA we might (do) overwrite freshly
dma'ed data by dirty Cache WB content.
Fixed by moving the "invalidate" at the beginning of dma_memcpy.
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
