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>
