(7-bit device address << 1), always leaving the room for the read/write bit.
This commit convert ti_i2c and revert r259127 on bcm2835_bsc to make them
compatible with 8-bit addresses. Previous to this commit an i2c device
would have different addresses depending on the controller it was attached
to (by example, when compared to any iicbb(4) based i2c controller), which
was a pretty annoying behavior.
Also, update the PMIC i2c address on beaglebone* DTS files to match the new
address scheme.
Now the userland utilities need to do the correct slave address shifting
(but it is going to work with any i2c controller on the system).
Discussed with: ian
MFC after: 2 weeks
The ti_i2c controller only works in the master mode and the i2c address
passed on iicbus_reset() is used to set the controller slave address when
operating as an i2c slave (which isn't currently supported).
When talking to a slave, the slave address is correctly provided to
ti_i2c_tranfer().
through a voltage divisor (R163 and R164 on page 4 of BBB schematic).
Add a note about this on ti_adc(4) man page. The ti_adc(4) man page will
first appear on 10.1-RELEASE.
MFC after: 1 week
Suggested by: Sulev-Madis Silber (ketas)
Manual page reviewed by: brueffer (D127)
and the actual PWM frequency.
Enforce the maximum value for the period sysctl.
The frequency systcl now allows the direct setting of the PWM frequency (it
will try to find the better clkdiv and period for a given frequency, i.e.
the ones that will give the better PWM resolution).
This allows the use lower frequencies on the PWM. Without changing the
clock prescaler the minimum PWM frequency was 1.52kHz.
PWM frequencies checked with an osciloscope.
PWM output tested with some R/C servos at 50Hz.
o Allow setting keymap in FDT, use hardcoded one by default
o Represent fallback keymap as a list rather than directly usable M*N array
Submitted by: Maxim Ignatenko <gelraen.ua@gmail.com>
current RADXA config. Radxa Rock (RR) boards have few types such as
RR (full version), RR Lite and some variants of RR engineering samples.
Add kernel config and FDT file for RR Lite board.
Approved by: stas (mentor)
(XScale mainly) expects the memory located before the kernel to be mapped,
and use it to allocate the page tables, the various stacks, etc.
A better fix would probably be to rewrite the various bla_machdep.c to stop
using that RAM, but I'm not so inclined to do it, especially since I don't
have hardware for all of them.
Use armv7_setttb that sets proper PT attributes.
Get rid of unused CPU functions, put nullop instead.
Exchange obsolete pj4b_/arm11_ functions to the appropriate armv7_ ones.
memory ordering model allows writes to different devices to complete out
of order, leading to a situation where the write that clears an interrupt
source at a device can complete after a write that unmasks and EOIs the
interrupt at the interrupt controller, leading to a spurious re-interrupt.
This adds a generic barrier function specific to the needs of interrupt
controllers, and calls that function from the GIC and TI AINTC controllers.
There may still be other soc-specific controllers that need to make the call.
Reviewed by: cognet, Svatopluk Kraus <onwahe@gmail.com>
MFC after: 3 days
shared flag is set on normal-memory mappings made via pmap_kenter() for SMP.
The "shared flag" part of this change isn't obvious from the diff, here's
the deal... by using the array of preformatted page table entry templates
instead of constructing the PTE from scratch, we automatically get the
right attribute bits set for both caching and shared.
MFC after: 1 week
platform code, it is expected these will be merged in the future when the
ARM code is more complete.
Until more boards can be tested only use this with the Raspberry Pi and
rrename the functions on the other SoCs.
Reviewed by: ian@
Here, "suitably endowed" means that the System Control Coprocessor
(#15) has Performance Monitoring Registers, including a CCNT (Cycle
Count) register.
The CCNT register is used in a way similar to the TSC register in
x86 processors by the get_cyclecount(9) function. The entropy-harvesting
thread is a heavy user of this function, and will benefit from not
having to call binuptime(9) instead.
One problem with the CCNT register is that it is 32-bit only, so
the upper 32-bits of the returned number are always 0. The entropy
harvester does not care, but in case any one else does, follow-up
work may include an interrup trap to increment an upper-32-bit
counter on CCNT overflow.
Another problem is that the CCNT register is not readable in user-mode
code; in can be made readable by userland, but then it is also
writable, and so is a good chunk of the PMU system. For that reason,
the CCNT is not enabled for user-mode access in this commit.
Like the x86, there is one CCNT per core, so they don't all run in
perfect sync.
Reviewed by: ian@ (an earlier version)
Tested by: ian@ (same earlier version)
Committed from: WANDBOARD-QUAD
that and the need to be in a critical section when switching to idleclock
mode for event timers, use spinlock_enter()/exit() to achieve both needs.
The ARM WFI (wait for interrupt) instruction blocks until an interrupt is
asserted, and it will unblock even if interrupts are masked, and it will
unblock immediately if an interrupt is already pending. It is necessary
to execute it with interrupts disabled, otherwise the interrupt that
should unblock it may occur and be serviced just prior to executing the
instruction. At that point the system is inappropriately asleep until
the next timer tick or some other random interrupt happens.
In general, interrupts need to be disabled continuously from the time the
decision is made that there is no work to be done and sleeping is needed
until actually going to sleep, to avoid a race where handling a new
interrupt changes the basis for deciding there is no work to be done.
Submitted by: hps@ (in slightly different form)
On modern ARM SoCs the L2 cache controller sits between the CPU and the
AXI bus, and most on-chip memory-mapped devices are on the AXI bus. We
map the device registers using the 'Device' memory attribute, which means
the memory is not cached, but writes to it are buffered. Ensuring that a
write has made it all the way to a device may require that the L2
controller take some action.
There is currently only one implementation of the new function, for the
PL310 cache controller. It invokes a function that the controller
manual calls "cache sync" but it actually has nothing to do with cache at
all, it triggers a drain of all pending store buffer writes and it blocks
until they complete.
The sheeva and xscale L2 controllers (which predate the concept of Device
memory) don't seem to have a corresponding function. It appears that the
standard armv5 drain_writebuf function includes draining all the way
through the L2 controller.
