Read the enable register to determine if the clock is already in use by
the firmware. In this case avoid gating the clock.
Tested-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Darren Hart (VMware) <dvhart@infradead.org>
Signed-off-by: Carlo Caione <carlo@endlessm.com>
Fixes: 282a4e4ce5 ("platform/x86: Enable Atom PMC platform clocks")
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Due to timing requirements, TI and Conexant manage the audio
reference clock from their ASoC codec drivers using the "mclk"
string. This patch adds another lookup for the "pmc_plt_clk_3"
clock to avoid Intel-specific tests in those codec drivers and
use code as-is.
To avoid a leak, clk_add_alias() is not used in this patch.
Instead the lookup is created manually as part of the .probe()
step and dropped in the .remove() step.
"pmc_plt_clk_3" is used exclusively for audio on all known
Baytrail/CherryTrail designs and is e.g. routed on the MCLK
(pin 26) of the MinnowBoardMAX Turbot LSE connector.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
The BayTrail and CherryTrail platforms provide platform clocks
through their Power Management Controller (PMC).
The SoC supports up to 6 clocks (PMC_PLT_CLK[0..5]) with a
frequency of either 19.2 MHz (PLL) or 25 MHz (XTAL) for BayTrail
and a frequency of 19.2 MHz (XTAL) for CherryTrail. These clocks
are available for general system use, where appropriate, and each
have Control & Frequency register fields associated with them.
Port from legacy by Pierre Bossart, integration in clock framework
by Irina Tirdea
Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
This driver is a clk provider and not a clk consumer, so remove
the clk.h include. Also, drop clkdev.h because there's not clkdev
usage here either.
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
This flag is a no-op now. Remove usage of the flag.
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Intel BayTrail has almost the same Low Power Subsystem than Lynxpoint with
few differences. Peripherals are clocked with different speeds (typically
lower) and the clock is not always gated. To support this we add
possibility to share a common fixed rate clock and make clock gating
optional.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The DMA controller in Lynxpoint is enumerated as a regular ACPI device now. To
work properly it is using the LPSS root clock as a functional clock. That's why
we have to register the clock device accordingly to the ACPI ID of the DMA
controller. The acpi_lpss.c module is responsible to do the job.
This patch also removes hardcoded name of the DMA device in clk-lpt.c and the
name of the root clock in acpi_lpss.c.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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>
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>
Carlo Caione