A future patch will implement a clock uclass driver for Tegra. That driver
will call into Tegra's existing clock code to simplify the transition;
this avoids tieing the clock uclass patches into significant refactoring
of the existing custom clock API implementation.
Some of the Tegra clock APIs that manipulate peripheral clocks require
both the peripheral clock ID and parent clock ID to be passed in together.
However, the clock uclass API does not require any such "parent"
parameter, so the clock driver must determine this information itself.
This patch implements new Tegra- specific clock API
clock_get_periph_parent() for this purpose.
The new API is implemented in the core Tegra clock code rather than SoC-
specific clock code. The implementation uses various SoC-/clock-specific
data. That data is only available in SoC-specific clock code.
Consequently, two new internal APIs are added that enable the core clock
code to retrieve this information from the SoC-specific clock code. Due to
the structure of the Tegra clock code, this leads to some unfortunate code
duplication. However, this situation predates this patch.
Ideally, future work will de-duplicate the Tegra clock code, and migrate
it into drivers/clk/tegra. However, such refactoring is kept separate from
this series.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
Currently, Tegra peripheral drivers control two aspects of their HW module
clock(s):
1) The clock enable/rate for the peripheral clock itself.
2) The system-level clock tree setup, i.e. the clock parent.
Aspect 1 is reasonable, but aspect 2 is a system-level decision, not
something that an individual peripheral driver should in general know
about or influence. Such system-level knowledge ties the driver to a
specific SoC implementation, even when they use generic APIs for clock
manipulation, since they must have SoC-specific knowledge such as parent
clock IDs. Limited exceptions exist, such as where peripheral HW is
expected to dynamically switch between clock sources at run-time, such
as CPU clock scaling or display clock conflict management in a multi-head
scenario.
This patch enhances the Tegra core code to perform system-level clock
tree setup, in a similar fashion to the Linux kernel Tegra clock driver.
This will allow future patches to simplify peripheral drivers by removing
the clock parent setup logic.
This change is required prior to converting peripheral drivers to use the
standard clock APIs, since:
1) The clock uclass doesn't currently support a set_parent() operation.
Adding one is possible, but not necessary at the moment.
2) The clock APIs retrieve all clock IDs from device tree, and the DT
bindings for almost all peripherals only includes information about the
relevant peripheral clocks, and not any potential parent clocks.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
Enabling a PLL while IDDQ is high. The Linux kernel checks for this
condition and warns about it verbosely, so while this seems to work
fine, fix it up according to the programming guidelines provided in
the Tegra K1 TRM (v02p), Section 5.3.8.1 ("PLLC and PLLC4 Startup
Sequence"). The Tegra114 TRM doesn't contain this information, but
the programming of PLLC is the same on Tegra114 and Tegra124.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
While clk_m and the oscillator run at the same frequencies on Tegra114
and Tegra124, clk_m is the proper source for the architected timer. On
more recent Tegra generations, Tegra210 and later, both the oscillator
and clk_m can run at different frequencies. clk_m will be divided down
from the oscillator.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
We have flipped CONFIG_SPL_DISABLE_OF_CONTROL. We have cleansing
devices, $(SPL_) and CONFIG_IS_ENABLED(), so we are ready to clear
away the ugly logic in include/fdtdec.h:
#ifdef CONFIG_OF_CONTROL
# if defined(CONFIG_SPL_BUILD) && !defined(SPL_OF_CONTROL)
# define OF_CONTROL 0
# else
# define OF_CONTROL 1
# endif
#else
# define OF_CONTROL 0
#endif
Now CONFIG_IS_ENABLED(OF_CONTROL) is the substitute. It refers to
CONFIG_OF_CONTROL for U-boot proper and CONFIG_SPL_OF_CONTROL for
SPL.
Also, we no longer have to cancel CONFIG_OF_CONTROL in
include/config_uncmd_spl.h and scripts/Makefile.spl.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Added PLL variables (dividers mask/shift, lock enable/detect, etc.)
to new pllinfo struct for each Soc/PLL. PLLA/C/D/E/M/P/U/X.
Used pllinfo struct in all clock functions, validated on T210.
Should be equivalent to prior code on T124/114/30/20. Thanks
to Marcel Ziswiler for corrections to the T20/T30 values.
Signed-off-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Tested-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>
