Previous SLC management implementation is broken. Seems like it was
never sufficiently tested probably because most of the time IOC was used
instead (i.e. no manual cache operations were done).
Now if we disable IOC in U-boot we'll get a lot of errors while using
DMA-enabled peripherals.
This time we fix it by substitution of broken per-line SLC operations
region operations as it is done in the Linux kernel (we took it from
v4.14 which is the latest stable as of today).
Among other things this implementation might be a bit faster because
instead of iteration over each and every cache line we're taking care
about entire region in one go.
Main changes:
* Replaced __slc_line_op (per line operations) by __slc_rgn_op
(region operations).
* Reworked __slc_entire_op to get rid of __after_slc_op and
__before_slc_op functions.
Note flush fix (flush only instead of flush-n-inv when OP_FLUSH is
used, see [1] for more details) is already incorporated here.
* Added SLC invalidation to invalidate_icache_all().
* Added (start >= end) check to invalidate_dcache_range() and
flush_dcache_range() as some buggy drivers pass region start == end.
* Added read-out of MMU BCR so we may know if PAE40 exists in HW and then
act on a particular AUX regs accordingly.
[1] http://lists.infradead.org/pipermail/linux-snps-arc/2018-January/003357.html
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
ARCNUM [15:8] field in ARC_AUX_IDENTITY register allows us to
uniquely identify each core in a multi-core system.
I.e. with help of this macro each core may get its index in SMP system.
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
This commit introduces timer driver for ARC.
ARC timers are configured via ARC AUX registers so we use special
functions to access timer control registers.
This driver allows utilization of either timer0 or timer1
depending on which one is available in real hardware. Essentially
only existing timers should be mentioned in board's Device Tree
description.
Signed-off-by: Vlad Zakharov <vzakhar@synopsys.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
This commit introduces timer driver for ARC.
ARC timers are configured via ARC AUX registers so we use special
functions to access timer control registers.
This driver allows utilization of either timer0 or timer1
depending on which one is available in real hardware. Essentially
only existing timers should be mentioned in board's Device Tree
description.
Signed-off-by: Vlad Zakharov <vzakhar@synopsys.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
With release of ARC HS38 v2.1 new IO coherency engine could be built-in
ARC core. This hardware module ensures coherency between DMA-ed data
from peripherals and L2 cache.
With L2 and IOC enabled there's no overhead for L2 cache manual
maintenance which results in significantly improved IO bandwidth.
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
[1] Align cache management functions to those in Linux kernel. I.e.:
a) Use the same functions for all cache ops (D$ Inv/Flush)
b) Split cache ops in 3 sub-functions: "before", "lineloop" and
"after". That way we may re-use "before" and "after" functions for
region and full cache ops.
[2] Implement full-functional L2 (SLC) management. Before SLC was
simply disabled early on boot. It's also possible to enable or disable
L2 cache from config utility.
[3] Disable/enable corresponding caches early on boot. So if U-Boot is
configured to use caches they will be used at all times (this is useful
in partucular for speed-up of relocation).
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
ARCv2 cores may have built-in SLC (System Level Cache, AKA L2-cache).
This change adds functions required for controlling SLC:
* slc_enable/disable
* slc_flush/invalidate
For now we just disable SLC to escape DMA coherency issues until either:
* SLC flush/invalidate is supported in DMA APIin U-Boot
* hardware DMA coherency is implemented (that might be board specific
so probably we'll need to have a separate Kconfig option for
controlling SLC explicitly)
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Now we may select a particular version of ARC700:
* ARC750D or
* ARC770D
It allows more flexible (or more fine tuned) configuration of U-Boot.
Before that change we relied on minimal configuration but now we may
use specific features of each CPU.
Moreover allows us to escape manual selection of options that
exist in both CPUs but may have say different version like MMUv2 in
ARC750D vs MMUv3 in ARC770D.
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Some cache operations ({i|d}cache_{enable|disable|status} or
flush_dcache_all) are built and used even if CONFIG_SYS_{I|D}CACHE_OFF
is set.
This is required for force disable of caches on early boot.
What if something was executed before U-boot and enabled caches
(low-level bootloaders, previously run kernel etc.)?
But if CPU doesn't really have caches any attempt to access
cache-related AUX registers triggers instruction error exception.
So for convenience we'll try to avoid exceptions by checking if CPU
actually has caches (we check separately data and instruction cache
existence) at all.
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Igor Guryanov <guryanov@synopsys.com>
These are header files used by ARC700 architecture.
Also note that "arch-arc700/hardware.h" is only required for compilation of
"designware_i2c" driver which refers to "asm/arch/hardware.h".
It would be good to fix mentioned driver sometime soon but it will cause
changes in ARM board configs that use "designware_i2c".
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Francois Bedard <fbedard@synopsys.com>
Cc: Wolfgang Denk <wd@denx.de>
Cc: Heiko Schocher <hs@denx.de>
Eugeniy Paltsev
Vlad Zakharov
Alexey Brodkin
Alexey Brodkin
Igor Guryanov