linux_dsm_epyc7002/arch/arc
Eugeniy Paltsev 2820a708d5 ARC: dma [IOC] Enable per device io coherency
So far the IOC treatment was global on ARC, being turned on (or off)
for all devices in the system. With this patch, this can now be done
per device using the "dma-coherent" DT property; IOW with this patch
we can use both HW-coherent and regular DMA peripherals simultaneously.

The changes involved are too many so enlisting the summary below:

1. common code calls ARC arch_setup_dma_ops() per device.

2. For coherent dma (IOC) it plugs in generic @dma_direct_ops which
   doesn't need any arch specific backend: No need for any explicit
   cache flushes or MMU mappings to provide for uncached access

   - dma_(map|sync)_single* return early as corresponding dma ops callbacks
     are NULL in generic code.
     So arch_sync_dma_*() -> dma_cache_*() need not handle the coherent
     dma case, hence drop ARC __dma_cache_*_ioc() which were no-op anyways

3. For noncoherent dma (non IOC) generic @dma_noncoherent_ops is used
   which in turns calls ARC specific routines

   - arch_dma_alloc() no longer checks for @ioc_enable since this is
     called only for !IOC case.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
[vgupta: rewrote changelog]
2018-09-04 13:21:37 -07:00
..
boot ARC: dma [IOC]: mark DMA devices connected as dma-coherent 2018-08-31 12:47:26 -07:00
configs ARC: [plat-axs*]: Enable SWAP 2018-08-27 09:00:36 -07:00
include ARC: dma [IOC] Enable per device io coherency 2018-09-04 13:21:37 -07:00
kernel ARC: cleanup show_faulting_vma() 2018-08-27 09:00:36 -07:00
lib ARC: dw2 unwind: enable cfi pseudo ops in string lib 2016-09-30 14:48:22 -07:00
mm ARC: dma [IOC] Enable per device io coherency 2018-09-04 13:21:37 -07:00
oprofile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
plat-axs10x ARC: [plat-axs103] refactor the quad core DT quirk code 2017-12-20 12:41:45 -08:00
plat-eznps arc: [plat-eznps] fix printk warning in arc/plat-eznps/mtm.c 2018-07-30 11:48:49 -07:00
plat-hsdk ARCv2: [plat-hsdk]: Save accl reg pair by default 2018-07-19 10:36:45 -07:00
plat-sim ARC: [plat-sim] Include this platform unconditionally 2017-08-04 13:49:47 +05:30
plat-tb10x arc: select GPIOLIB directly 2016-04-26 14:07:59 +02:00
Kbuild ARC: Build system: Makefiles, Kconfig, Linker script 2013-02-11 20:00:25 +05:30
Kconfig ARC: sort Kconfig 2018-08-27 09:00:36 -07:00
Kconfig.debug Kconfig: consolidate the "Kernel hacking" menu 2018-08-02 08:06:48 +09:00
Makefile arc: remove redundant GCC version checks 2018-08-30 17:51:44 -07:00