But there is a difference in the way it is done here. If PAE is not enabled,
PDE_SIZE = 4, so there is no NOX bit set. If PAE is enabled, PDE_SIZE = 8,
so the NOX bit is set.
This works exactly as intended, since NOX does not exist in the non-PAE
case.
So here is a patch to get basic ski console output working. The ski
simulator was decoding the wrong registers in ssccnputc() due to
automagically inlined ssc() which contains a "break" simulated system
call.
The ski loader "skiload" has almost exactly the same inline assembly
call for ssc(), but for whatever reason, (maybe ssc() and
ski_cons_putchar() are in different files?), the ssc() function didn't
get inlined and I/O worked fine.
in the Xen ld scripts, so that it can compile. We put the __rodata_start
definition right before __data_start, for it to appear as dead code, since
the rodata segment is not yet mapped independently on Xen.
The change ensures that ifnet objects in the ifnet list aren't freed during
list iterations by using pserialize(9) and psref(9).
Note that the change adds a pslist(9) for ifnet but doesn't remove the
original ifnet list (ifnet_list) to avoid breaking kvm(3) users. We
shouldn't use the original list in the kernel anymore.
When CPU0 is launched, EFER_NXE is enabled in it, and it allows it to
handle pages that have the NOX bit. When the secondary CPUs are
launched, however, EFER_NXE is enabled only after paging is set in their
%cr0. And therefore, between the moment when paging is enabled and the
moment when EFER_NXE is enabled, the secondary CPUs cannot access pages
that have the NOX bit - they crash if they try to.
The funny thing is that in order to enable EFER_NXE, the secondary CPUs
give a look at cpu_feature[2], which is in the DATA segment, which in
turn could have the NOX bit. In other words, the secondary CPUs crash if
the DATA segment is mapped with the NOX bit.
Fix this by enabling EFER_NXE in the secondary CPUs before enabling
paging. CPU0 initializes nox_flag to the 32bit version of PG_NX if NOX
is supported; the secondary CPUs then use nox_flag to know whether NOX
is supported.
nox_flag will be used for other purposes soon.
http://mail-index.netbsd.org/tech-kern/2016/04/28/msg020504.html
add gpio interrupt support to the gpio framework, and an implementation
for the allwinner gpio backend (tested on A20 only).
gpio(4) has new public functions:
- gpio_intr() called by backends when an interrupt condition for
a gpio pin is present
- gpio_find_device() and gpio_get_name(), support functions for
gpio(4) users, wich respectively returns a void * cookie for a gpio device
given its name, and returns the name given the cookie.
- gpio_pin_ctl_intr(), which is used to configure interrupts on a gpio pin and
registers a callback.
- gpio_pin_irqen(), which is used to mask/unmask interrupts on a pin.
Nothing in the NetBSD tree uses this yet, but I have a i2c driver
(at https://github.com/mbouyer/marine_chartplotter/tree/master/software/NetBSD/driver) which uses it.
