Date: Sun, 26 Oct 2003 21:45:35 -0800 (PST) From: Marcel Moolenaar <marcel@FreeBSD.org> To: src-committers@FreeBSD.org, cvs-src@FreeBSD.org, cvs-all@FreeBSD.org Subject: cvs commit: src/sys/ia64/ia64 sys_machdep.c src/sys/ia64/include sysarch.h Message-ID: <200310270545.h9R5jZXX036739@repoman.freebsd.org>
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marcel 2003/10/26 21:45:35 PST
FreeBSD src repository
Modified files:
sys/ia64/ia64 sys_machdep.c
sys/ia64/include sysarch.h
Log:
Add support for userland to access I/O port space. This is primarily
added for XFree86. There are 2 reasons for doing this with sysarch():
1. The memory mapped I/O space is not at a fixed physical address. An
application has to use some interface to get the base address. It
gets worse if the machine has multiple memory mapped I/O spaces.
2. Access to the memory mapped I/O space needs to happen through a
translation that is flagged as uncachable. There's no interface
that allows a process to do uncached memory I/O, other than though
/dev/mem (possibly).
So, until we either disallow direct access to I/O or bus space from
userland or have a better way of doing this, sysarch() has the least
negative impact on existing interfaces.
Revision Changes Path
1.7 +70 -28 src/sys/ia64/ia64/sys_machdep.c
1.2 +13 -12 src/sys/ia64/include/sysarch.h
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