The AT91 clock drivers make use of IRQs to avoid polling when waiting for
some clocks to be enabled. Unfortunately, this leads to a crash when those
IRQs are threaded (which happens when using preempt-rt) because they are
registered before thread creation is possible.
Use polling on those clocks instead to avoid the problem.
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Use the regmap coming from syscon to access the registers instead of using
pmc_read/pmc_write. This allows to avoid passing the at91_pmc structure to
the child nodes of the PMC.
The final benefit is to have each clock register itself instead of having
to iterate over the children.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
This patch adds new at91 master clock implementation using common clk
framework.
The master clock layout describe the MCKR register layout.
There are 2 master clock layouts:
- at91rm9200
- at91sam9x5
Master clocks are given characteristics:
- min/max clock output rate
These characteristics are checked during rate change to avoid
over/underclocking.
These characteristics are described in atmel's SoC datasheet in
"Electrical Characteristics" paragraph.
Signed-off-by: Boris BREZILLON <b.brezillon@overkiz.com>
Acked-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>