3 commits

Author	SHA1	Message	Date
Michael Sevakis	a36a498c57	i.MX31/Gigabeat S: This should fix stability problems. One problem was to start using the DVFS controller properly so that interrupts will be masked at the lowest and highest frequency indexes. Millions of useless interrupts were occurring at 132MHz because its index was 2, not 3, which masks it automatically when it can't go slower. Stopping the flood was enough to actually see the difference in general. IRQ must be disabled when fiddling with the CCM registers and only enabled when waiting for voltage ramp as having them enables also causes spurious DVFS ints. Implement interruptible ISR pro/epilogue more safely (always using IRQ stack even in SVC mode handling). Fix an improper inequality in DVFS code (which set regs for down when going up and v.v.). Misc. support changes. Have internal tables take less RAM. ... git-svn-id: svn://svn.rockbox.org/rockbox/trunk@25837 a1c6a512-1295-4272-9138-f99709370657	2010-05-06 03:23:51 +00:00
Michael Sevakis	11cca264ff	i.MX31/Gigabeat S: Implement frequency and voltage scaling-- 1.6V for 528MHz, and 1.35V for 264MHz and 132MHz. Keep DPTC overdrive ( > 400MHz) voltage scaling off for now because of uncertainties. Simplify the (working) mess later. ... git-svn-id: svn://svn.rockbox.org/rockbox/trunk@25699 a1c6a512-1295-4272-9138-f99709370657	2010-04-23 15:32:50 +00:00
Michael Sevakis	87eea33def	Gigabeat S (imx31): Begin voltage and frequency scaling code. For now, to avoid overdrive voltage, just lower core voltage to 1.35V since voltage scaling shouldn't be required for frequencies lower than 399 MHz (according to Freescale BSP, which set all working points to 1.35V for those frequencies). Perhaps battery life will improve as well (cross fingers :). ... git-svn-id: svn://svn.rockbox.org/rockbox/trunk@25506 a1c6a512-1295-4272-9138-f99709370657	2010-04-07 03:43:48 +00:00