Add Clock Domain support to the Clock Pulse Generator (CPG) Module Stop
(MSTP) Clocks driver using the generic PM Domain. This allows to
power-manage the module clocks of SoC devices that are part of the
CPG/MSTP Clock Domain using Runtime PM, or for system suspend/resume.
SoC devices that are part of the CPG/MSTP Clock Domain and can be
power-managed through an MSTP clock should be tagged in DT with a
proper "power-domains" property.
The CPG/MSTP Clock Domain code will scan such devices for clocks that
are suitable for power-managing the device, by looking for a clock that
is compatible with "renesas,cpg-mstp-clocks".
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
The MSTP[SC]R registers have clock stop bits, not clock enable bits. The
bit value should thus be inverted in the is_enabled() operation.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
With the addition of clock-indices, we need to change the renesas
clock implementation to use these instead of the local definition
of "renesas,clock-indices".
Since this will break booting with older device trees, we add a
simple auto-detection of which properties are present.
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
If the driver needs to change a clock rate, then it must be propogated
through the MSTP clock to the parent clock (such as shdi0 -> sd0). Without
this we cannot up-rate default clocks which are really slow (such as the
mmcif1 which defaults to 12MHz where it could be running at 97MHz)
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
The clks member of the clk_onecell_data structure should
point to a valid clk array (no NULL entries allowed),
and the clk_num should be equal to the number
of elements in the clks array.
The MSTP driver fails to satisfy the above conditions.
The clks array may contain NULL entries if not all
clock-indices are initialized in the device tree.
Thus, if the clock indices are interleaved we end up
with NULL pointers in-between.
The other problem is the driver uses maximum clock index
as the number of clocks, which is incorrect (less than
the actual number of clocks by 1).
Fix the first issue by pre-setting the whole clks array
with ERR_PTR(-ENOENT) pointers instead of zeros; and
use maximum clkidx + 1 as the number of clocks to fix
the other one.
This should make of_clk_src_onecell_get() return the following:
* valid clk pointers for all clocks registered;
* ERR_PTR(-EINVAL) if (idx >= clk_data->clk_num);
* ERR_PTR(-ENOENT) if the clock at the selected index was not
initialized in the device tree (and was not registered).
Changes in V2:
* removed brackets from the one-line for loop
Signed-off-by: Valentine Barshak <valentine.barshak@cogentembedded.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
Use clkidx when registering MSTP clocks instead of loop counter
since the value is then used to access the specific clock index bit
in the mstp register.
The issue was introduced by the following commit:
f94859c215 "clk: shmobile: Add MSTP clock support"
Changes in V2:
* none
Signed-off-by: Valentine Barshak <valentine.barshak@cogentembedded.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
MSTP clocks are gate clocks controlled through a register that handles
up to 32 clocks. The register is often sparsely populated.
Those clocks are found on Renesas ARM SoCs.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
