clk: starfive: jh7100: Add CLK_SET_RATE_PARENT to gmac_tx

This is needed by the dwmac-starfive ethernet driver to set the clock
for 1000, 100 and 10 Mbps links properly.

Signed-off-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://lore.kernel.org/r/20231219232442.2460166-3-cristian.ciocaltea@collabora.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: starfive: Add flags argument to JH71X0__MUX macro

This flag is needed to add the CLK_SET_RATE_PARENT flag on the gmac_tx
clock on the JH7100, which in turn is needed by the dwmac-starfive
driver to set the clock properly for 1000, 100 and 10 Mbps links.

This change was mostly made using coccinelle:

@ match @
expression idx, name, nparents;
@@
JH71X0__MUX(
-idx, name, nparents,
+idx, name, 0, nparents,
...)

Signed-off-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://lore.kernel.org/r/20231219232442.2460166-2-cristian.ciocaltea@collabora.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: starfive: Rename "jh7100" to "jh71x0" for the common code

Rename some variables from "jh7100" or "JH7100" to "jh71x0"
or "JH71X0".

Tested-by: Tommaso Merciai <tomm.merciai@gmail.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Signed-off-by: Hal Feng <hal.feng@starfivetech.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>

clk: starfive: Rename clk-starfive-jh7100.h to clk-starfive-jh71x0.h

Rename clk-starfive-jh7100.h to clk-starfive-jh71x0.h for making
the code to be common.

Tested-by: Tommaso Merciai <tomm.merciai@gmail.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Signed-off-by: Hal Feng <hal.feng@starfivetech.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>

clk: starfive: Factor out common JH7100 and JH7110 code

The clock control registers on the StarFive JH7100 and JH7110 work
identically, so factor out the code then drivers for the two SoCs
can share it without depending on each other. No functional change.

Tested-by: Tommaso Merciai <tomm.merciai@gmail.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Signed-off-by: Hal Feng <hal.feng@starfivetech.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>

clk: starfive: jh7100: Support more clock types

Unlike the system clocks there are audio clocks that combine both
multiplexer/divider and gate/multiplexer/divider, so add support for
that.

Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Link: https://lore.kernel.org/r/20220126173953.1016706-7-kernel@esmil.dk
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: starfive: jh7100: Make hw clock implementation reusable

The JH7100 has additional audio and video clocks at different memory
ranges, but they use the same register layout. Add a header and export
the starfive_jh7100_clk_ops function so the clock implementation can be
reused by drivers handling these clocks.

Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Link: https://lore.kernel.org/r/20220126173953.1016706-6-kernel@esmil.dk
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: starfive: jh7100: Handle audio_div clock properly

It turns out the audio_div clock is a fractional divider where the
lowest byte of the ctrl register is the integer part of the divider and
the 2nd byte is the number of 100th added to the divider.

The children of this clock is used by the audio peripherals for their
sample rate clock, so round to the closest possible rate rather than
always rounding down like regular dividers.

Fixes: 4210be668a09 ("clk: starfive: Add JH7100 clock generator driver")
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Link: https://lore.kernel.org/r/20220126173953.1016706-3-kernel@esmil.dk
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: starfive: jh7100: Don't round divisor up twice

The problem is best illustrated by an example. Suppose a consumer wants
a 4MHz clock rate from a divider with a 10MHz parent. It would then
call

clk_round_rate(clk, 4000000)

which would call into our determine_rate() callback that correctly
rounds up and finds that a divisor of 3 gives the highest possible
frequency below the requested 4MHz and returns 10000000 / 3 = 3333333Hz.

However the consumer would then call

clk_set_rate(clk, 3333333)

but since 3333333 doesn't divide 10000000 evenly our set_rate() callback
would again round the divisor up and set it to 4 which results in an
unnecessarily low rate of 2.5MHz.

Fix it by using DIV_ROUND_CLOSEST in the set_rate() callback.

Fixes: 4210be668a09 ("clk: starfive: Add JH7100 clock generator driver")
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Link: https://lore.kernel.org/r/20220126173953.1016706-2-kernel@esmil.dk
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: starfive: Add JH7100 clock generator driver

Add a driver for the StarFive JH7100 clock generator.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Co-developed-by: Emil Renner Berthing <kernel@esmil.dk>
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>