Commit facb87ad75 ("clk: at91: sama7g5: remove prescaler part of master
clock") removed the master clock's prescaler from clock tree of SAMA7G5
as it has been discovered that there is a hardware bug when trying to
change it at run-time (bug is described in description of
commit facb87ad75 ("clk: at91: sama7g5: remove prescaler part of master
clock")). This was previously changed at CPUFreq driver request. Thus, with
commit facb87ad75 ("clk: at91: sama7g5: remove prescaler part of master
clock") there is no need of code that handles run-time changes of master
clock's prescaler, thus remove this code.
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20220203110202.18329-1-claudiu.beznea@microchip.com
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>
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>
