This version works on both 26-bit and 32-bit machines. For large copies,
it's up to three times as fast as the old arm32 version and five times as
fast as the old arm26 version. For small copies it seems to be even faster
(getrusage() is apparently over ten times faster on an ARM610).
Hooray for Allen!
counters. These counters do not exist on all CPUs, but where they
do exist, can be used for counting events such as dcache misses that
would otherwise be difficult or impossible to instrument by code
inspection or hardware simulation.
pmc(9) is meant to be a general interface. Initially, the Intel XScale
counters are the only ones supported.
page tables.
- pmap_enter(): if making a mapping for the same PA rw->ro, write-back
the cache before doing so.
- pmap_clearbit(): if revoking REF on a page, make sure to wbinv the
cache if the page has write permission, else inv the cache if the page's
PTE is valid (XXX we actually wbinv in this case, as well, due to lack
of idcache_inv_range()). Only flush the TLB if the PTE changed.
nathanw_sa branch.
* In switch_exit(), set the outgoing-proc register to NULL (rather than
proc0) so that we actually use the "exiting process" optimization in
cpu_switch().
Unit. The AAU provides block fill, block copy, XOR, and XOR-parity-check
operations. We currently provide dmover(9) functions for "zero", "fill8",
and "copy".
Much of this code can be shared with the i80312 Companion I/O AAU, and
will be when support for the older chip is implemented.
A new "arm32_dma_range" structure now describes a DMA window, with
a system address base, bus address base, and length. In addition to
providing info about which memory regions are legal for DMA, the new
structure provides address translation support, as well.
As before, if a tag does not list any ranges, then all addresses are
considered valid, and no DMA address translation is performed.
This allows us to remove a large chunk of code which was duplicated and
tweaked slightly (to do the address translation) from the stock ARM
bus_dma in the XScale IOP and ARM Integrator ports.
Test compiled on all ARM platforms, test booted on Intel IQ80321 and Shark.
into platform-specific initialization code, giving platform-specific
code control over which free list a given chunk of memory gets put
onto.
Changes are essentially mechanical. Test compiled for all ARM
platforms, test booted on Intel IQ80321 and Shark.
Discussed some time ago on port-arm.
the virtual address for each DMA segment, just cache a pointer to the
original buffer/buftype used to load the DMA map, and use that. This
lets us shrink the bus_dma_segment_t down from 12 bytes to 8, and the
cache flushing is also more efficient.
Tested on an i80321 -- changes to others are mechanical.
