mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-10-28 15:20:41 +00:00
8b0f578898
pcc_send_data() can be invoked during the execution of performance critical code as in cppc_cpufreq driver. With acpi_* APIs, the doorbell register accessed in pcc_send_data() if present in system memory will be searched (in cached virt to phys addr mapping), mapped, read/written and then unmapped. These operations take significant amount of time. This patch maps the performance critical doorbell register during init and then reads/writes to it directly using the mapped virtual address. This patch + similar changes to CPPC acpi driver reduce the time per freq. transition from around 200us to about 20us for the CPPC cpufreq driver Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org> Acked-by: Ashwin Chaugule <ashwin.chaugule@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> |
||
---|---|---|
.. | ||
arm_mhu.c | ||
bcm2835-mailbox.c | ||
Kconfig | ||
mailbox-altera.c | ||
mailbox-sti.c | ||
mailbox-test.c | ||
mailbox.c | ||
mailbox.h | ||
Makefile | ||
omap-mailbox.c | ||
pcc.c | ||
pl320-ipc.c |