Get rid of asc_cpu_stop() which was never a thing. The CPU start bit
should always be off in the steady state, it is only used momentarily to
start the CPU.
Signed-off-by: Hector Martin <marcan@marcan.st>
Technically both can be done unconditionally, but let's be explicit in
the python side to see if we ever find this algorithm doesn't work.
Signed-off-by: Hector Martin <marcan@marcan.st>
Add script which prints out the (rough) measured impedance of connected
headphones on machines with the CS42L84 jack codec (2021 Macbook Pros).
$ proxyclient/experiments/ohmmeter.py
Waiting for plug... measuring... 64.3 ohms... yanked
Waiting for plug... measuring... 697.1 ohms...
Signed-off-by: Martin Povišer <povik@protonmail.com>
Fix reading of registers (there have been STOPs issued between the two
messages which surprisingly went unnoticed until now). Also add support
for multibyte register addresses.
Signed-off-by: Martin Povišer <povik@protonmail.com>
Commit 9c795fbdbf introduced the pair of
WFE and SEV for spinlock, but it caused delays of tens of seconds. A
possible explanation for the delay is lack of data synchronization
barrier between the store instruction and SEV instruction.
Arm Architecture Reference Manual for A-profile architecture (issue H.a)
says:
> Arm recommends that software includes a Data Synchronization Barrier
> (DSB) instruction before any SEV instruction. The DSB instruction
> ensures that no instructions, including any SEV instructions, that
> appear in program order after the DSB instruction, can execute until
> the DSB instruction has completed.
However, inserting a DSB instruction still didn't resolve the delay.
The exclusive load is an alternative to the SEV instruction. The manual
says:
> ...However, in Armv8, when the global monitor for a PE changes from
> Exclusive Access state to Open Access state, an event is generated.
> This is equivalent to issuing an SEVL instruction on the PE for which
> the monitor state has changed. It removes the need for spinlock code
> to include an SEV instruction after clearing a spinlock.
As an additional benefit, the exclusive load is local to the PE and
eliminates spurious events for other PEs.
Trusted Firmware-A v2.6 also employs the same algorithm.
Signed-off-by: Akihiko Odaki <akihiko.odaki@gmail.com>
Do not go through a formatted cmdline string when invoking tools. There
are user-controlled paths involved which can contain spaces (and other
foul characters).
Signed-off-by: Martin Povišer <povik@protonmail.com>
If an explicitly specified display mode exceeds the allocated
framebuffer allocate a new one from the top of RAM.
Note: macOS panics immediately with a realloced framebuffer.
Signed-off-by: Janne Grunau <j@jannau.net>
DART nodes for dcp and disp0 have pre-allocated L1 and L2 tables which
are annotated in the ADT. The pre-allocated memory is specified in
"pt-region-${DEVICE}". The first page is used as L1 table and the
following pages are used as L2 tables. The number of valid L2 tables is
specified in "l2-tt-${DEVICE}". The first entry identifies the region
and the second entry is the number of valid L2 tables.
iboot (macOS 12.3) inits just 2 L2 tables. Larger framebuffers require
more. By using the pre-allocated page tables we do not have worry about
keeping the memory mapped after m1n1 executes the next target.
Signed-off-by: Janne Grunau <j@jannau.net>
The reserved framebuffer on the Mac Studio is 0x854000 bytes. This is
too small for 1920x1200 with 4 byte per pixel. Setting 1920x1200 as
mode crashes dcp but not the actual display controller. The display
remains working and even comes back after display hotplug/power cycle.
Signed-off-by: Janne Grunau <j@jannau.net>
The device tree for multi die SoCs as the M1 Ultra has its devices
under "/soc/dieX" instead of directly under "/soc".
Signed-off-by: Janne Grunau <j@jannau.net>
