The am35x family of SoCs has several differences from standard OMAP3 SoCs that haven't been accounted for in Linux ARM code. These differences include: - There is no IVA. - The device doesn't not support RETENTION & OFF power states. - The SDRC *module* has an EMIF4 submodule instead of an SDRC submodule. This series of patches tries to account for those changes. They do the following: - Prevent the cpu_idle thread and cpu_idle driver from sleeping because there are no I/O wake-ups to wake things back up again. - Add a new cpu feature that indicates whether the device supports RETENTION & OFF power states. Add code to support devices that only have INACTIVE & ON states. - Add a parallel set of clockdomain dependencies that don't include the IVA. - Add a new cpu feature that indicates whether the device has an EMIF4 or SDRC submodule of the SDRC module (the SDRC term/acronym is overloaded). Add a minimal amount of code to support the EMIF4 submodule. - Some miscellaneous patches to fix issues found while developing & testing the changes outlined above. With these patches, the am3517 EVM boots and suspend-to-RAM functions. Unfortunately, though, after all of this, I still can't manage to get the CORE power domain to enter the INACTIVE state (at least according to /sys/kernel/debug/pm_debug/count with debugfs mounted under /sys/kernel/debug). The EMIF4 support is fairly minimal because there is an EMIF driver working its way to mainline. If more changes are necessary, they can be made once the final version of that driver is in mainline. Please note that the SDRC submodule mapping is used by the EMIF4 code. They are at the same physical addresses and are the same size so it works okay. The reason I left the mapping alone is because when those mappings are made, its too early to use cpu_is_xxx() or omap3_has_sdrc_emif4() and I didn't want to bloat the kernel with something that's not strictly necessary. I already have the code for the separate mappings, so adding it in is easy, if that's preferred. I tried to make the mapping reuse clear with the commit log and by adding a comment in am35xx_init_early(). These patches are based on the latest mainline kernel as of this writing, commit 258f742635360175564e9470eb060ff4d4b984e7, (modpost: Fix modpost license checking of vmlinux.o). That kernel with these patches was tested on an am35x EVM, am37x EVM, and a Beagleboard-xM. Testing included suspend-to-RAM (i.e., "echo mem > /sys/power/state") with a rootfs mounted from mmc and nfs (except for the Beagleboard-xM). Mark -- -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
