Commit Graph

17 Commits

Author SHA1 Message Date
Scott Long
5193a34646 Implement bus_dmamem_alloc_size() and bus_dmamem_free_size() as
counterparts to bus_dmamem_alloc() and bus_dmamem_free().  This allows
the caller to specify the size of the allocation instead of it defaulting
to the max_size field of the busdma tag.

This is intended to aid in converting drivers to busdma.  Lots of
hardware cannot understand scatter/gather lists, which forces the
driver to copy the i/o buffers to a single contiguous region
before sending it to the hardware.  Without these new methods, this
would require a new busdma tag for each operation, or a complex
internal allocator/cache for each driver.

Allocations greater than PAGE_SIZE are rounded up to the next
PAGE_SIZE by contigmalloc(), so this is not suitable for multiple
static allocations that would be better served by a single
fixed-length subdivided allocation.

Reviewed by:	jake (sparc64)
2003-01-29 07:25:27 +00:00
Sam Leffler
14c17bd293 New bus_dma interfaces for use by crypto device drivers:
o bus_dmamap_load_mbuf
o bus_dmamap_load_uio

Test on i386.  Known to compile on alpha and sparc64, but not tested.
Otherwise untried.
2002-10-04 20:40:39 +00:00
Yoshihiro Takahashi
31b2da2bea - Moved the bus_dma declarations from bus_{at386,pc98}.h into bus_dma.h.
(bus_dma.h is repo-copied from bus_at386.h)
- Added '#include <machine/bus_dma.h>' into bus.h for backward compatibility.
2001-10-06 16:27:21 +00:00
Alexander Langer
90f76f2df0 Fix "alignemnt" typo. 2001-06-16 15:28:28 +00:00
Matthew N. Dodd
c7411c02f5 version 1.7 made some changes to correct problems identifed by compiling
with egcs-1.1.1.  bus_space_write_multi_2() had an extra operation that
should have been removed.

Remove it.

This fixes the panic when bus_space_write_multi_2() is used.

Obtained from:		jake
2001-03-02 05:33:53 +00:00
John Baldwin
3f4809dd0d Axe the barrier_{read,write,rw}() helper functions as this method of
doing memory barriers doesn't really scale well for the ia64.  Also,
memory barriers are more a property of the CPU than bus space.

Requested by:	dfr
2000-10-20 06:45:48 +00:00
John Baldwin
25f3f7c530 Add in a simple API for memory barriers to machine/bus.h:
- barrier_read() enforces a memory read barrier
- barrier_write() enforces a memory write barrier
- barrier_rw() enforces a memory read/write barrier
2000-10-18 10:30:12 +00:00
Bruce Evans
933aec2f75 Fixed syntax errors and style bugs in previous commit. The syntax
errors were normally harmless because they were in unreachable code
and gcc apparently doesn't check the syntax inside asm statements
that it optimizes away.
2000-06-14 18:48:39 +00:00
Mike Smith
f0ba8e211c Implement real read/write barriers for the i386. Despite the comment in
previous versions of this file, some barrier functionality is required.
2000-05-18 00:06:10 +00:00
KATO Takenori
91cb959ddb Added indirect pio into the bus space stuff for the NEC PC-98. bus.h
includes one of bus_at386.h and bus_pc98.h. Becuase only bus_pc98.h
supports indirect pio and bus_at386.h is identical to old bus.h, there
is no functional change in PC-AT's kernels.  That is, it cannot cause
performance loss.

Submitted by:	nyan
Reviewed by:	imp
bde and luoqi provided useful comments for earlier version.
2000-03-29 03:15:22 +00:00
David E. O'Brien
dfe41fc832 Fix clobbers so that GENERIC may compile with GCC 2.95.2.
Historically, the documentation of extended asm was lacking, namely you
should NOT specify the same register as an input, and a clobber.
If the register is clobbered, it should be specified as an output as well,
e.g., by linking input and output through the "number" notation.
(Beware of lvalues, some local variables needed...)

URL:http://egcs.cygnus.com/faq.html

In versions up to egcs-1.1.1, the compiler did not even warn about it,
but it was liable to output bad code. Newer egcs are pickier and simply
refuse to swallow such code.

Note, since *addr changes, it needs to be an output operand.
We might be excessive in saying that all memory has changed.

Obtained from:	OpenBSD
		w/extra thanks to Marc Espie <Marc.Espie@liafa.jussieu.fr>
1999-11-14 03:36:34 +00:00
Peter Wemm
c3aac50f28 $Id$ -> $FreeBSD$ 1999-08-28 01:08:13 +00:00
Warner Losh
279f2101e7 Improve compatibility with other systems by changing the default
behavior slightly.

If machine/bus.h is included, but neither bus_memio.h nor bus_pio.h
are included, then behave as if both were included.

This won't change existing drivers, all of which include one or more
of bus_{p,mem}io.h, but will allow drivers from other systems to come
over with fewer changes.  I freely admit that this might not be
optimal for some drivers, but those drivers can be optimized for
FreeBSD after the initial bringup happens.

Without the change, there is a bug that preclude drivers from
compiling with strange warning/errors.

I've been running this here for a while now w/o ill effects.

Reviewed by: gibbs
Not objected to by: bde, arch@ list.
1999-07-03 20:14:08 +00:00
Bruce Evans
0c71101cb7 Don't pretend to support ix86's with 16-bit ints by using longs just
to ensure 32-bit variables.  Doing so broke ix86's with 64-bit longs.
1998-09-29 09:06:00 +00:00
Justin T. Gibbs
8fddb21ee2 Implement bus_dmamem_* functions and correct a few nits reported by Peter Wemm. 1998-05-06 01:45:55 +00:00
Bruce Evans
8c4a6d7452 Support compiling with `gcc-pedantic' (don't use hard newlines in
(asm) string constants or trailing commas in enum declarations).
1998-04-19 15:28:30 +00:00
Justin T. Gibbs
e1a1bba4fa Implementation of Bus Space for FreeBSD-x86.
Obtained From: NetBSD
1998-01-15 07:32:56 +00:00