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authorDave Jiang <dave.jiang@intel.com>2021-07-15 11:44:47 -0700
committerVinod Koul <vkoul@kernel.org>2021-07-21 10:09:16 +0530
commit6e7f3ee97bbe2c7d7a53b7dbd7a08a579e03c8c9 (patch)
treec9e9476cf28d5b54ee9ab97a7dbd1e2a40fd1fbf /drivers/dma/Kconfig
parentd9e5481fca74f870cf2fc2f90a0e77e85c0b5b86 (diff)
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dmaengine: idxd: move dsa_drv support to compatible mode
The original architecture of /sys/bus/dsa invented a scheme whereby a single entry in the list of bus drivers, /sys/bus/drivers/dsa, handled all device types and internally routed them to different different drivers. Those internal drivers were invisible to userspace. With the idxd driver transitioned to a proper bus device-driver model, the legacy behavior needs to be preserved due to it being exposed to user space via sysfs. Create a compat driver to provide the legacy behavior for /sys/bus/dsa/drivers/dsa. This should satisfy user tool accel-config v3.2 or ealier where this behavior is expected. If the distro has a newer accel-config then the legacy mode does not need to be enabled. When the compat driver binds the device (i.e. dsa0) to the dsa driver, it will be bound to the new idxd_drv. The wq device (i.e. wq0.0) will be bound to either the dmaengine_drv or the user_drv. The dsa_drv becomes a routing mechansim for the new drivers. It will not support additional external drivers that are implemented later. Reviewed-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/162637468705.744545.4399080971745974435.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'drivers/dma/Kconfig')
-rw-r--r--drivers/dma/Kconfig17
1 files changed, 17 insertions, 0 deletions
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index d7101bff1772..ceb41be0505e 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -295,6 +295,23 @@ config INTEL_IDXD
If unsure, say N.
+config INTEL_IDXD_COMPAT
+ bool "Legacy behavior for idxd driver"
+ depends on PCI && X86_64
+ select INTEL_IDXD_BUS
+ help
+ Compatible driver to support old /sys/bus/dsa/drivers/dsa behavior.
+ The old behavior performed driver bind/unbind for device and wq
+ devices all under the dsa driver. The compat driver will emulate
+ the legacy behavior in order to allow existing support apps (i.e.
+ accel-config) to continue function. It is expected that accel-config
+ v3.2 and earlier will need the compat mode. A distro with later
+ accel-config version can disable this compat config.
+
+ Say Y if you have old applications that require such behavior.
+
+ If unsure, say N.
+
# Config symbol that collects all the dependencies that's necessary to
# support shared virtual memory for the devices supported by idxd.
config INTEL_IDXD_SVM