SH-5, meet NetBSD.
Let's hope this is the start of a long and fruitful relationship. :-)
This code, funded by Wasabi Systems, adds initial support for the
Hitachi SuperH(tm) SH-5 cpu architecture to NetBSD.
At the present time, NetBSD/evbsh5 only runs on a SH-5 core simulator
which has no simulated devices other than a simple console. However, it
is good enough to get to the "root device: " prompt.
Device driver support for Real SH-5 Hardware is in place, particularly for
supporting the up-coming Cayman evaluation board, and should be quite
easy to get running when the hardware is available.
There is no in-tree toolchain for this port at this time. Gcc-current has
rudimentary SH-5 support but it is known to be buggy. A working toolchain
was obtained from SuperH to facilitate this port. Gcc-current will be
fixed in due course.
The SH-5 architecture is fully 64-bit capable, although NetBSD/evbsh5 has
currently only been tested in 32-bit mode. It is bi-endian, via a boot-
time option and it also has an "SHcompact" mode in which it will execute
SH-[34] user-land instructions.
For more information on the SH-5, see www.superh.com. Suffice to say it
is *not* just another respin of the SH-[34].
* struct sigacts gets a new sigact_sigdesc structure, which has the
sigaction and the trampoline/version. Version 0 means "legacy kernel
provided trampoline". Other versions are coordinated with machine-
dependent code in libc.
* sigaction1() grows two more arguments -- the trampoline pointer and
the trampoline version.
* A new __sigaction_sigtramp() system call is provided to register a
trampoline along with a signal handler.
* The handler is no longer passed to sensig() functions. Instead,
sendsig() looks up the handler by peeking in the sigacts for the
process getting the signal (since it has to look in there for the
trampoline anyway).
* Native sendsig() functions now select the appropriate trampoline and
its arguments based on the trampoline version in the sigacts.
Changes to libc to use the new facility will be checked in later. Kernel
version not bumped; we will ride the 1.6C bump made recently.
mappings bus_dma(9) states: "In the event that the DMA handle contains
a valid mapping, the mapping will be unloaded via the same mechanism
used by bus_dmamap_unload()." And some drivers do mean to skip the
unload step.
scw