the temporary mappings that are used to implement operations like
pmap_zero_page(). There is no reason for the MIPS pmap to deviate
from that practice.
having PTE_RO set instead of PTE_D. This avoids some unnecessary failures
by pmap_extract_and_hold() that will have to be handled by a call to
vm_fault_hold(). Testing the PTE for both being non-zero and having PTE_V
set is redundant. The latter suffices.
pmap_unmapdev()'s own direct efforts to destroy the page table entries are
redundant, so eliminate them.
Don't set PTE_W on the page table entry in pmap_kenter{,_attr}() on MIPS.
Setting PTE_W on MIPS is inconsistent with the implementation of this
function on other architectures. Moreover, PTE_W should not be set, unless
the pmap's wired mapping count is incremented, which pmap_kenter{,_attr}()
doesn't do.
MFC after: 10 days
Avoid re-walking the page table from the root for every PTE examined.
Tidy up some of pmap_remove()'s helper functions.
pmap_enter:
Set PV_TABLE_REF whenever the physical page being mapped is managed, not
just when it is writeable.
Only call pmap_update_page() when the old mapping was valid. If there was
no prior valid mapping, then pmap_update_page() serves no useful purpose.
However, it will interrupt every processor that has the pmap active.
pmap_enter_quick_locked:
Always set PTE_RO.
pmap_emulate_modified:
Don't set PV_TABLE_REF.
Eliminate a nonsensical comment.
allocating them on the stack of various bus_dmamap_load*() functions. The
S/G lists are stored in the DMA tags. This matches the implementation on
all other platforms.
Discussed with: scottl, gibbs
Tested by: stas (arm@)
comment describing them. Both the function names and the comment had grown
stale. Quite some time has passed since these pmap implementations last
used the page's hold count to track the number of valid mapping within a
page table page. Also, returning TRUE from pmap_unwire_ptp() rather than
_pmap_unwire_ptp() eliminates a few instructions from callers like
pmap_enter_quick_locked() where pmap_unwire_ptp()'s return value is used
directly by a conditional statement.
* add cam as a module to build - but build in scbus/da for now, as
"cam" as a module includes all cam devices. Hardly space saving.
* Don't build FFS snapshot support.
This has an AR7240 SoC with an AR9285 wireless NIC on-board.
Since the kernel partition on the 4MiB flash is 960KiB, quite a bit
is disabled to try and squeeze the build into that. Even lzma'ed,
it's still quite large.
802.11n router.
The flash layout defaults to a 1 MiB section for the kernel so I'm trying
very hard to squeeze a minimialistic (LZMA compressde) kernel image into
that.
I've verified that it boots through to single user mode fine.
Issues:
* USB doesn't yet work as a module - I need to add something else to the
USB AR71xx build before that will work.
* There's no switch PHY support - but for now it quite happily behaves
as a useful dumb switch out of the box. Phew.
* Since a previous flash attempt trashed my radio configuration block,
I haven't yet verified whether the wireless works correctly.
I'll test that out shortly (read: once I re-calibrate the board somehow.)
Thanks to ray@ and the zrouter project for doing some of the initial
hard work in figuring out how to bring this board up.
Terasic DE-4 board. Allow LED configuration to be set using loader
tunables, not just from userspace, and preconfigure LED 8 as a kernel
heartbeat. For now, this is a Nexus-attached, BERI-only driver, but it
could be used with other hard and soft cores on Altera FPGAs as well, in
principle.
Sponsored by: DARPA, AFRL
are written out.
This allows EEPROM-less NICs on the AR7241 PCIe bus to be correctly
initialised.
Tested:
* AP91 (AR7240+AR9285) - the existing board support didn't break;
* AP99 (AR7241+AR9287) - this fixed the configuration of the AR9287 PCI.
used with Terasic's DE-4 and other similar FPGA boards. This display
is 800x480 and includes a capacitive touch screen, multi-touch
gesture recognition, etc. This device driver depends on a Cambridge-
provided IP core that allows the MTL device to be hooked up to the
Altera Avalon SoC bus, and also provides a VGA-like text frame buffer.
Although it is compiled as a single device driver, it actually
implements a number of different device nodes exporting various
aspects of this multi-function device to userspace:
- Simple memory-mapped driver for the MTL 24-bit pixel frame buffer.
- Simple memory-mapped driver for the MTL control register set.
- Simple memory-mapped driver for the MTL text frame buffer.
- syscons attachment for the MTL text frame buffer.
This driver attaches directly to Nexus as is common for SoC device
drivers, and for the time being is considered BERI-specific, although
in principle it might be used with other hard and soft cores on
Altera FPGAs.
Control registers, including touchscreen input, are simply memory
mapped; in the future it would be desirable to hook up a more
conventional device node that can stream events, support kqueue(2)/
poll(2)/select(2), etc.
This is the first use of syscons on MIPS, as far as I can tell, and
there are some loose ends, such as an inability to use the hardware
cursor. More fundamentally, it appears that syscons(4) assumes that
either a host is PC-like (i386, amd64) *or* it must be using a
graphical frame buffer. While the MTL supports a graphical frame
buffer, using the text frame buffer is preferable for console use.
Fixing this issue in syscons(4) requires non-trivial changes, as the
text frame buffer support assumes that direct memory access can be
done to the text frame buffer without using bus accessor methods,
which is not the case on MIPS. As a workaround for this, we instead
double-buffer and pretend to be a graphical frame buffer exposing
text accessor methods, leading to some quirks in syscons behaviour.
Sponsored by: DARPA, AFRL
The driver attempts to support all documented parts, but has only been
tested with the 512Mbit part on the Terasic DE4 FPGA board. It should be
trivial to adapt the driver's attach routine to other embedded boards
using with any parts in the family.
Also import isfctl(8) which can be used to erase sections of the flash.
Sponsored by: DARPA, AFRL
which presents a UART-like interface over the Avalon bus that can be
addressed over JTAG. This IP core proves extremely useful, allowing us to
connect trivially to the FreeBSD console over JTAG for FPGA-embedded hard
and soft cores. As interrupts are optionally configured for this soft
core, we support both interrupt-driven and polled modes of operation,
which must be selected using device.hints. UART instances appear in /dev
as ttyu0, ttyu1, etc.
However, it also contains a number of quirks, which make it difficult to
tell when JTAG is connected, and some buffering issues. We work around
these as best we can, using various heuristics.
While the majority of this device driver is not only not BERI-specific,
but also not MIPS-specific, for now add its defines in the BERI files
list, as the console-level parts are aware of where the first JTAG UART
is mapped on Avalon, and contain MIPS-specific address translation, to
use before Newbus and device.hints are available.
Sponsored by: DARPA, AFRL
Bluespec Extensible RISC Implementation (BERI) processor. BERI is a 64-bit
MIPS ISA soft CPU core that can be synthesised to Altera and Xilinx FPGAs,
and is being used for CPU and OS research at several institutions.
Sponsored by: DARPA, AFRL
on PowerPC support. This was clearly not something syscons was
designed to do (very specific assumptions about the nature of VGA
consoles on PCs), but fortunately others have long since blazed
the way on making it work regardless of that.
Sponsored by: DARPA, AFRL
type, explicitly print out "unknown" rather than the empty string, and
include the exception type number for ease of debugging.
Sponsored by: DARPA, AFRL
r239274 added support for ranges. Update XLP DTS to provide the correct
range parameter for the XLP SoC bus. Also fix bus_space_map method
for XLP bus space.
Submitted by: Sreekanth M. <sreekanth.molagavalli@broadcom.com>
First, pmap_clear_modify() is write protecting all mappings to the specified
page, not just clearing the modified bit. Specifically, it sets PTE_RO on
the PTE, which is wrong. Moreover, it is calling vm_page_dirty(), which is
not the expected behavior for pmap_clear_modify(). Generally speaking, the
machine-independent VM layer masks these mistakes. For example, setting
PTE_RO will result in additional soft faults, but not a catastrophe.
Second, pmap_clear_modify() may not clear the modified bits because it only
iterates over the PV list when the page has the PV_TABLE_MOD flag set and
elsewhere the pmap clears the PV_TABLE_MOD flag anytime a modified mapping
is write protected or destroyed. However, the page may still have other
mappings with the modified bit set.
Eliminate a stale comment.
to this pmap.
Tidy up the #include's.
Remove the (now) unused #define PMAP_SHPGPERPROC. (This should have
been removed in r239236.)
Tested by: jchandra
advantages. First, PV entries are roughly half the size. Second, this
allocator doesn't access the paging queues, and thus it will allow for the
removal of the page queues lock from this pmap.
Fix a rather serious bug in pmap_remove_write(). After removing write
access from the specified page's first mapping, pmap_remove_write() then
used the wrong "next" pointer. Consequently, the page's second, third,
etc. mappings were not write protected.
Tested by: jchandra
The machine-independent parts of the virtual memory system always pass a
valid pmap to the pmap functions that require one. Remove the checks for
NULL. (These checks have their origins in the Mach pmap.c that was
integrated into BSD. None of the new code written specifically for
FreeBSD included them.)
