CCF clocks should always use the struct clock passed to their methods for
extracting the driver-specific clock information struct. Previously, many
functions would use the clk->dev->priv if the device was bound. This could
cause problems with composite clocks. The individual clocks in a composite
clock did not have the ->dev field filled in. This was fine, because the
device-specific clock information would be used. However, since there was
no ->dev, there was no way to get the parent clock. This caused the
recalc_rate method of the CCF divider clock to fail. One option would be to
use the clk->priv field to get the composite clock and from there get the
appropriate parent device. However, this would tie the implementation to
the composite clock. In general, different devices should not rely on the
contents of ->priv from another device.
The simple solution to this problem is to just always use the supplied
struct clock. The composite clock now fills in the ->dev pointer of its
child clocks. This allows child clocks to make calls like clk_get_parent()
without issue.
imx avoided the above problem by using a custom get_rate function with
composite clocks.
Signed-off-by: Sean Anderson <seanga2@gmail.com>
Acked-by: Lukasz Majewski <lukma@denx.de>
At present devres.h is included in all files that include dm.h but few
make use of it. Also this pulls in linux/compat which adds several more
headers. Drop the automatic inclusion and require files to include devres
themselves. This provides a good indication of which files use devres.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Anatolij Gustschin <agust@denx.de>
The generic mux clock code for CCF requires reading the clock multiplexer
value from HW registers. As sandbox by design has readl() as no-op it was
necessary to provide this value in the other way.
The new field in the mux structure (accessible only when sandbox is run)
has been introduced for this purpose.
Signed-off-by: Lukasz Majewski <lukma@denx.de>
This patch brings the files from Linux kernel (linux-stable/linux-5.1.y
SHA1: 5752b50477da)to provide clocks support as it is used on the Linux
kernel with Common Clock Framework [CCF] setup.
The directory structure has been preserved. The ported code only supports
reading information from PLL, MUX, Divider, etc and enabling/disabling
the clocks USDHCx/ECSPIx depending on used bus. Moreover, it is agnostic
to the alias numbering as the information about the clock is read from the
device tree.
One needs to pay attention to the comments indicating necessary for U-Boot's
driver model changes.
If needed, the code can be extended to support the "set" part of the clock
management.
Signed-off-by: Lukasz Majewski <lukma@denx.de>
