SAMA7G5 supports DVFS by changing cpuck. On SAMA7G5 mck0 shares the same
parent with cpuck as seen in the following clock tree:
+----------> cpuck
|
FRAC PLL ---> DIV PLL -+-> DIV ---> mck0
mck0 could go b/w 32KHz and 200MHz on SAMA7G5. To avoid mck0 overclocking
while changing FRAC PLL or DIV PLL the commit implements a notifier for
mck0 which applies a safe divider to register (maximum value of the divider
which is 5) on PRE_RATE_CHANGE events (such that changes on PLL to not
overclock mck0) and sets the maximum allowed rate on POST_RATE_CHANGE
events.
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Link: https://lore.kernel.org/r/20211011112719.3951784-13-claudiu.beznea@microchip.com
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
These are all "early clocks" that require initialization just at
of_clk_init() time. Use CLK_OF_DECLARE() to declare them.
This also fixes a problem that was spotted when fw_devlink was
set to 'on' by default: the boards failed to boot. The reason is
that CLK_OF_DECLARE_DRIVER() clears the OF_POPULATED and causes
the consumers of the clock to be postponed by fw_devlink until
the second initialization routine of the clock has been completed.
One of the consumers of the clock is the timer, which is used as a
clocksource, and needs the clock initialized early. Postponing the
timers caused the fail at boot.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Link: https://lore.kernel.org/r/20210203154332.470587-1-tudor.ambarus@microchip.com
Acked-by: Saravana Kannan <saravanak@google.com>
Tested-by: Eugen Hristev <eugen.hristev@microchip.com>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Re-factor master clock driver by splitting it into 2 clocks: prescaller
and divider clocks. Based on registered clock flags the prescaler's rate
could be changed at runtime. This is necessary for platforms supporting
DVFS (e.g. SAMA7G5) where master clock could be changed at run-time.
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Link: https://lore.kernel.org/r/1605800597-16720-11-git-send-email-claudiu.beznea@microchip.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Some peripheral clocks on SAMA7G5 supports requesting parent to change
its rate (image related clocks: csi, csi2dc, isc). Add support
so that if registered with this option the clock rate to be
requested from parent.
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Link: https://lore.kernel.org/r/1595403506-8209-14-git-send-email-claudiu.beznea@microchip.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
syscon_node_to_regmap() will make the created regmap get and enable the
first clock it can parse from the device tree. This clock is not needed to
access the registers and should not be enabled at that time.
Use device_node_to_regmap to resolve this as it looks up the regmap in
the same list but doesn't care about the clocks. This issue is detected
by lockdep when booting the sama5d3 with a device tree containing the
new clk bindings.
This fix already happened in 6956eb33ab ("clk: at91: fix possible
deadlock") for the drivers that had been migrated to the new clk binding
back then. This does the same for the new drivers as well.
Fixes: 01e2113de9 ("clk: at91: add sam9x60 pmc driver")
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Link: https://lore.kernel.org/r/20200703073236.23923-1-a.fatoum@pengutronix.de
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
We need to have clocks accessible via phandle to select them
as peripheral clock parent using assigned-clock-parents in DT.
Add support for PLLACK/PLLBCK/AUDIOPLLCK clocks where available.
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lkml.kernel.org/r/fa39cc10dab8341ea4bc2b7152be9217b2cd34a5.1588630999.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
