|author||Chris Metcalf <firstname.lastname@example.org>||2010-06-25 17:00:56 -0400|
|committer||Chris Metcalf <email@example.com>||2010-07-06 13:34:15 -0400|
arch/tile: Add driver to enable access to the user dynamic network.
This network (the "UDN") connects all the cpus on the chip in a wormhole-routed dynamic network. Subrectangles of the chip can be allocated by a "create" ioctl on /dev/hardwall, and then to access the UDN in that rectangle, tasks must perform an "activate" ioctl on that same file object after affinitizing themselves to a single cpu in the region. Sending a wormhole-routed message that tries to leave that subrectangle causes all activated tasks to receive a SIGILL (just as they would if they tried to access the UDN without first activating themselves to a hardwall rectangle). The original submission of this code to LKML had the driver instantiated under /proc/tile/hardwall. Now we just use a character device for this, conventionally /dev/hardwall. Some futures planning for the TILE-Gx chip suggests that we may want to have other types of devices that share the general model of "bind a task to a cpu, then 'activate' a file descriptor on a pseudo-device that gives access to some hardware resource". As such, we are using a device rather than, for example, a syscall, to set up and activate this code. As part of this change, the compat_ptr() declaration was fixed and used to pass the compat_ioctl argument to the normal ioctl. So far we limit compat code to 2GB, so the difference between zero-extend and sign-extend (the latter being correct, eventually) had been overlooked. Signed-off-by: Chris Metcalf <firstname.lastname@example.org> Acked-by: Arnd Bergmann <email@example.com>
Diffstat (limited to 'arch/tile/Kconfig')
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/tile/Kconfig b/arch/tile/Kconfig
index 290ef416193..1eb308cb711 100644
@@ -310,6 +310,10 @@ config VMALLOC_RESERVE
+ bool "Hardwall support to allow access to user dynamic network"
+ default y
endmenu # Tilera-specific configuration
menu "Bus options"