It's common that UARTs are bound and probed before U-Boot relocation,
in which case the clocks of UART and UART's pincontroller must be
registered first. Let's apply DM_FLAG_PRE_RELOC to the driver, allowing
it to bind before relocation.

Signed-off-by: Yao Zi <ziyao@disroot.org>
Reviewed-by: Leo Yu-Chi Liang <ycliang@andestech.com>

Unlike the gate clocks which make no use of flags, most dividers in
TH1520 SoC are one-based, thus are applied with CLK_DIVIDER_ONE_BASED
flag. We couldn't simply ignore the flag, which causes wrong results
when calculating the clock rates.

Add a member to ccu_div_internal for defining the flags, and pass it to
divider_recalc_rate(). With this fix, frequency of all the clocks match
the Linux kernel's calculation.

Fixes: e6bfa6fc94f ("clk: thead: Port clock controller driver of TH1520 SoC")
Signed-off-by: Yao Zi <ziyao@disroot.org>
Acked-by: Leo Yu-Chi Liang <ycliang@andestech.com>

The driver is adapted from Linux kernel's version of clk-th1520-ap.c,
with only output clocks for external sensors, which are barely useful in
bootloaders, removed.

Same as the mainline driver, it currently lacks of ability to enable and
reconfigure PLLs, which could be implemented later.

Signed-off-by: Yao Zi <ziyao@disroot.org>
Reviewed-by: Leo Yu-Chi Liang <ycliang@andestech.com>