Mostly for the sake of reducing latency for audio servicing where other service
routines can take a long time to complete, leading to occasional drops of a
few samples, especially in recording, where they are fairly frequent.
One mystery that remains is GPIOA IRQ being interrupted causes strange
undefined instruction exceptions, most easily produced on my Fuze V2 with a
scrollwheel. Making GPIOA the top ISR for now, thus not interruptible, cures it.
SVC mode is used during the actual calls. Hopefully the SVC stack size is
sufficient. Prologue and epilogue code only uses the IRQ stack and is large
enough.
Any routine code that should not be interrupted should disable IRQ itself from
here on in.
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@31642 a1c6a512-1295-4272-9138-f99709370657
Reserve 1MB of DRAM for loading rockbox and use the rest as BSS
Write sdram setup in assembler and move it to a separate file, together
with MMU init code
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@26926 a1c6a512-1295-4272-9138-f99709370657
We do not need a stack pointer at this step, and we are sure to not use
memory not initialized yet (like bss)
Fixes FS#11114 (tested on Fuze)
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@25229 a1c6a512-1295-4272-9138-f99709370657
Introduce a new .init section for initialisation code, so that it can be copied to an area which is later overwritten before calling. The stack/bss can then overwrite that code, effectively freeing the code size that the initialisation routines need. Gives a few kB ram usage back.
Only implemented for PP and as3525 so far. More targets could be added, as well as more functions.
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@25013 a1c6a512-1295-4272-9138-f99709370657
Substract 4 before passing the argument to UIE so the correct address is displayed
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@24321 a1c6a512-1295-4272-9138-f99709370657
- cache IRAM and DRAM
- map IRAM just next to DRAM to remove the need for -mlong-calls and reduce binsize
- tweak delays in Fuze button code
- tweak delays in Clip button code (down button sometimes doesn't respond anyway : an alternate driver is being worked on)
Before reporting any problem, please check your filesystem or format your player from the OF
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@21228 a1c6a512-1295-4272-9138-f99709370657
For example if running from SDRAM, we need to copy the vectors to offset 0
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@19044 a1c6a512-1295-4272-9138-f99709370657
* Moved crt0.S to imx31 subdirectory, as it was the last target using the unified file.
* DRAM is now remapped to 0x0, facilitating interrupts (which aren't done yet)
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@15965 a1c6a512-1295-4272-9138-f99709370657
Make PNX0101-specific system.c and crt0.S.
Add new register names from LPC2880 user manual.
Add support for timer.
Enable CPU frequency changing.
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@12904 a1c6a512-1295-4272-9138-f99709370657
