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>
