Latching the clock settings is needed with certain clocks, where
the setting is "cached" in HW before doing the actual re-programming
of the clock source. This patch adds support for clock latching to
the divider clock.
Signed-off-by: Tero Kristo <t-kristo@ti.com>
Omit extra messages for a memory allocation failure in these
functions.
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Commit 6c0afb5039 ("clk: ti: convert to use proper register
definition for all accesses") converted all register accesses in
the TI clk driver to use a proper struct instead of a void
pointer casted struct that fits into a u32. Unfortunately, it
missed a conversion here in the didivder code, leading to a
compiler warning like so:
drivers/clk/ti/divider.c: In function 'ti_clk_register_divider':
drivers/clk/ti/divider.c:460:8: error: 'reg' may be used uninitialized in this function [-Werror=maybe-uninitialized]
Treating a 'u32' variable as a structure leads to a stack
overflow here, and the register address we pass down is never
initialized. Convert this part of the code as well so things
work properly.
Fixes: 6c0afb5039 ("clk: ti: convert to use proper register definition for all accesses")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
[sboyd@codeaurora.org: Fixed fixes tag, rewrote commit message,
s/reg_setup/reg/]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Currently, TI clock driver uses an encapsulated struct that is cast into
a void pointer to store all register addresses. This can be considered
as rather nasty hackery, and prevents from expanding the register
address field also. Instead, replace all the code to use proper struct
in place for this, which contains all the previously used data.
This patch is rather large as it is touching multiple files, but this
can't be split up as we need to avoid any boot breakage.
Signed-off-by: Tero Kristo <t-kristo@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
This can be used from the divider itself, and also from the clkctrl
clocks once this is introduced.
Signed-off-by: Tero Kristo <t-kristo@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Instead of using the generic clock driver data struct, use one internal
for the TI clock driver itself. This allows modifying the register access
parts in subsequent patch.
Signed-off-by: Tero Kristo <t-kristo@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Currently the divider selection logic blindly divides the parent_rate
by the clk rate and gives the divider value for the divider clocks
which do not have the CLK_SET_RATE_PARENT flag set. Add the clk divider
table parsing to get the closest divider available in the table
provided via Device tree.
The code is pretty much taken from: drivers/clk/clk-divider.c.
and used here to fix up the best divider selection logic.
Signed-off-by: Keerthy <j-keerthy@ti.com>
Reported-by: Richard Woodruff <r-woodruff2@ti.com>
Acked-by: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
to_clk_*(_hw) macros have been repeatedly defined in many places.
This patch moves all the to_clk_*(_hw) definitions in the common
clock framework to public header clk-provider.h, and drop the local
definitions.
Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
TI's mux and divider clock drivers do not require locking and they do
not initialize internal spinlocks. This code was occasionally
copy-posted from generic mux/divider drivers. So remove it.
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Tero Kristo <t-kristo@ti.com>
We're removing struct clk from the clk provider API, so switch
this code to using the clk_hw based provider APIs.
Acked-by: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Mostly converted with the following snippet:
@@
struct clk_hw *E;
@@
-__clk_get_flags(E->clk)
+clk_hw_get_flags(E)
Acked-by: Tero Kristo <t-kristo@ti.com>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Acked-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Coquelin <mcoquelin.stm32@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
There is a case where NULL can be a valid return value for
ti_clk_get_reg_addr, specifically the case where both the provider index
and register offsets are zero. In this case, the current error checking
against a NULL pointer will fail. Thus, change the API to return a
ERR_PTR value in an error case, and change all the users of this API to
check against IS_ERR instead.
Signed-off-by: Tero Kristo <t-kristo@ti.com>
Acked-by: Michael Turquette <mturquette@linaro.org>
Legacy clock data is initialized slightly differently compared to
DT clocks, thus add support for this.
Signed-off-by: Tero Kristo <t-kristo@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
As written, the __init for ti_clk_get_div_table is in the middle of the return
type.
The gcc documentation indicates that section attributes should be added to the
end of the function declaration:
extern void foobar (void) __attribute__ ((section ("bar")));
However gcc seems to be very permissive with where attributes can be placed.
clang on the other hand isn't so permissive, and fails if you put the section
definition in the middle of the return type:
drivers/clk/ti/divider.c:298:28: error: expected ';' after struct
static struct clk_div_table
^
;
drivers/clk/ti/divider.c:298:1: warning: 'static' ignored on this
declaration [-Wmissing-declarations]
static struct clk_div_table
^
drivers/clk/ti/divider.c:299:9: error: type specifier missing,
defaults to 'int' [-Werror,-Wimplicit-int]
__init *ti_clk_get_div_table(struct device_node *node)
~~~~~~ ^
drivers/clk/ti/divider.c:345:9: warning: incompatible pointer types
returning 'struct clk_div_table *' from a function with result type 'int *' [-Wincompatible-pointer-types]
return table;
^~~~~
drivers/clk/ti/divider.c:419:9: warning: incompatible pointer types
assigning to 'const struct clk_div_table *' from 'int *' [-Wincompatible-pointer-types]
*table = ti_clk_get_div_table(node);
^ ~~~~~~~~~~~~~~~~~~~~~~~~~~
3 warnings and 2 errors generated.
By convention, most of the kernel code puts section attributes between the
return type and function name. In the case where the return type is a pointer,
it's important to place the '*' on left of the __init.
This updated code works for both gcc and clang.
Signed-off-by: Behan Webster <behanw@converseincode.com>
Reviewed-by: Mark Charlebois <charlebm@gmail.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Tero Kristo <t-kristo@ti.com>
Check for valid parameters in check rate. Else, we end up getting errors
like:
[ 0.000000] Division by zero in kernel.
[ 0.000000] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.17.0-rc1 #1
[ 0.000000] [<c0015160>] (unwind_backtrace) from [<c0011978>] (show_stack+0x10/0x14)
[ 0.000000] [<c0011978>] (show_stack) from [<c055f5f4>] (dump_stack+0x78/0x94)
[ 0.000000] [<c055f5f4>] (dump_stack) from [<c02e17cc>] (Ldiv0+0x8/0x10)
[ 0.000000] [<c02e17cc>] (Ldiv0) from [<c047d228>] (ti_clk_divider_set_rate+0x14/0x14c)
[ 0.000000] [<c047d228>] (ti_clk_divider_set_rate) from [<c047a938>] (clk_change_rate+0x138/0x180)
[ 0.000000] [<c047a938>] (clk_change_rate) from [<c047a908>] (clk_change_rate+0x108/0x180)
This occurs as part of the inital clock tree update of child clock nodes
where new_rate could be 0 for non functional clocks.
Fixes: b4761198bf ("CLK: ti: add support for ti divider-clock")
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Tero Kristo <t-kristo@ti.com>
ti/clk-divider.c does not calculate the rates consistently at the moment.
As an example, on OMAP3 we have a clock divider with a source clock of
864000000 Hz. With dividers 6, 7 and 8 the theoretical rates are:
6: 144000000
7: 123428571.428571...
8: 108000000
Calling clk_round_rate() with the rate in the first column will give the
rate in the second column:
144000000 -> 144000000
143999999 -> 123428571
123428572 -> 123428571
123428571 -> 108000000
Note how clk_round_rate() returns 123428571 for rates from 123428572 to
143999999, which is mathematically correct, but when clk_round_rate() is
called with 123428571, the returned value is surprisingly 108000000.
This means that the following code works a bit oddly:
rate = clk_round_rate(clk, 123428572);
clk_set_rate(clk, rate);
As clk_set_rate() also does clock rate rounding, the result is that the
clock is set to the rate of 108000000, not 123428571 returned by the
clk_round_rate.
This patch changes the ti/clk-divider.c to use DIV_ROUND_UP when
calculating the rate. This gives the following behavior which fixes the
inconsistency:
144000000 -> 144000000
143999999 -> 123428572
123428572 -> 123428572
123428571 -> 108000000
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
This patch adds support for TI divider clock binding, which simply uses
the basic clock divider to provide the features needed.
Signed-off-by: Tero Kristo <t-kristo@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
