acrn-kernel/drivers/clk/x86/Makefile

clk-x86-lpss-objs		:= clk-lpt.o
obj-$(CONFIG_X86_INTEL_LPSS)	+= clk-x86-lpss.o
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org> 2013-03-07 06:46:20 +08:00			`clk-x86-lpss-objs := clk-lpt.o`
clk: x86: add support for Lynxpoint LPSS clocks Intel Lynxpoint Low Power Subsystem hosts peripherals like UART, I2C and SPI controllers. For most of these there is a configuration register that allows software to enable and disable the functional clock. Disabling the clock while the peripheral is not used saves power. In order to take advantage of this we add a new clock gate of type lpss_gate that just re-uses the ordinary clk_gate but in addition is able to enumerate the base address register of the device using ACPI. We then create a clock tree that models the Lynxpoint LPSS clocks using these gates and fixed clocks so that we can pass clock rate to the drivers as well. Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Mike Turquette <mturquette@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 2013-01-18 21:46:00 +08:00			`obj-$(CONFIG_X86_INTEL_LPSS) += clk-x86-lpss.o`