The current driver calculates the clock divider with
fractional support enabled.
But it does not enable fractional support in the
control register itself resulting in an integer only divider,
but in clk_set_rate responds back the fractionally divided
clock frequency.
This patch enables fractional support in the control register
whenever there is a fractional bit set in the requested clock divider.
Mash clock limits are are also handled for the PWM clock
applying the correct divider limits (2 and max_int) applicable to
basic fractional divider support (mash order of 1).
It also adds locking to protect the read/modify/write cycle of
the register modification.
Fixes: 41691b8862 ("clk: bcm2835: Add support for programming the
audio domain clocks")
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Eric Anholt <eric@anholt.net>
Current clamping of a normal divider allows a value < 1 to be valid.
A divider of < 1 would actually only be possible if we had a PLL...
So this patch clamps the divider to 1.
Fixes: 41691b8862 ("clk: bcm2835: Add support for programming the
audio domain clocks")
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Eric Anholt <eric@anholt.net>
Add missing locking to:
* bcm2835_pll_divider_on
* bcm2835_pll_divider_off
to protect the read modify write cycle for the
register access protecting both cm_reg and a2w_reg
registers.
Fixes: 41691b8862 ("clk: bcm2835: Add support for programming the
audio domain clocks")
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Eric Anholt <eric@anholt.net>
bcm2835_pll_off is currently assigning CM_PLL_ANARST to the control
register, which may lose the other bits that are currently set by the
clock dividers.
It also now locks during the read/modify/write cycle of both
registers.
Fixes: 41691b8862 ("clk: bcm2835: Add support for programming the
audio domain clocks")
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Eric Anholt <eric@anholt.net>
The change fixes potential oops while accessing iomem on invalid
address, if devm_ioremap_resource() fails due to some reason.
The devm_ioremap_resource() function returns ERR_PTR() and never
returns NULL, which makes useless a following check for NULL.
Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>
Fixes: 5e63dcc74b ("clk: bcm2835: Add a driver for the auxiliary peripheral clock gates")
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
This flag is a no-op now. Remove usage of the flag.
Cc: Lee Jones <lee@kernel.org>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
We were rolling this ourselves, but clk-divider can do it now.
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
Our dividers weren't being set successfully because CM_PASSWORD wasn't
included in the register write. It looks easier to just compute the
divider to write ourselves than to update clk-divider for the ability
to OR in some arbitrary bits on write.
Fixes about half of the video modes on my HDMI monitor (everything
except 720x400).
Cc: stable@vger.kernel.org
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
Remove __init macro from all function prototypes in clk-iproc.h
Signed-off-by: Ray Jui <rjui@broadcom.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
This patch adds support for Broadcom Cygnus audio PLL and leaf
clocks
Signed-off-by: Simran Rai <ssimran@broadcom.com>
Reviewed-by: Scott Branden <sbranden@broadcom.com>
Signed-off-by: Ray Jui <rjui@broadcom.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Register the pwm clock for bcm2835.
Signed-off-by: Remi Pommarel <repk@triplefau.lt>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
Some bcm2835 clocks used by hardware (like "PWM" or "H264") can have multiple
parent clocks. These clocks divide the rate of a parent which can be selected by
setting the proper bits in the clock control register.
Previously all these parents where handled by a mux clock. But a mux clock
cannot be used because updating clock control register to select parent needs a
password to be xor'd with the parent index.
This patch get rid of mux clock and make these clocks handle their own parent,
allowing them to select the one to use.
Signed-off-by: Remi Pommarel <repk@triplefau.lt>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
Make bcm2835_clock_choose_div to optionally round up the chosen MASH divisor
so that the resulting average rate will not be higher than the requested one.
Signed-off-by: Remi Pommarel <repk@triplefau.lt>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
There are a pair of SPI masters and a mini UART that were last minute
additions. As a result, they didn't get integrated in the same way as
the other gates off of the VPU clock in CPRMAN.
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
BCM63138 has a simple clocking domain which is primarily the ARMPLL
clocking complex, from which the ARM (CPU), APB and AXI clocks would be
derived from.
Since the ARMPLL controller is entirely compatible with the iProc ARM
PLL, we just initialize it without additional parameters.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* clk-iproc:
clk: iproc: define Broadcom NS2 iProc clock binding
clk: iproc: define Broadcom NSP iProc clock binding
clk: ns2: add clock support for Broadcom Northstar 2 SoC
clk: iproc: Separate status and control variables
clk: iproc: Split off dig_filter
clk: iproc: Add PLL base write function
clk: nsp: add clock support for Broadcom Northstar Plus SoC
clk: iproc: Add PWRCTRL support
clk: cygnus: Convert all macros to all caps
ARM: cygnus: fix link failures when CONFIG_COMMON_CLK_IPROC is disabled
The Broadcom Northstar 2 SoC is architected under the iProc
architecture. It has the following PLLs: GENPLL SCR, GENPLL SW,
LCPLL DDR, LCPLL Ports, all derived from an onboard crystal.
Signed-off-by: Jon Mason <jonmason@broadcom.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Some PLLs have separate registers for Status and Control. The means the
pll_base needs to be split into 2 new variables, so that those PLLs can
specify device tree registers for those independently. Also, add a new
driver flag to identify this presence of the split, and let the driver
know that additional registers need to be used.
Signed-off-by: Jon Mason <jonmason@broadcom.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
The PLL loop filter/gain can be located in a separate register on some
SoCs. Split these off into a separate variable, so that an offset can
be added if necessary. Also, make the necessary modifications to the
Cygnus and NSP drivers for this change.
Signed-off-by: Jon Mason <jonmason@broadcom.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
All writes to the PLL base address must be flushed if the
IPROC_CLK_NEEDS_READ_BACK flag is set. If we add a function to make the
necessary write and reads, we can make sure that any future code which
makes PLL base writes will do the correct thing.
Signed-off-by: Jon Mason <jonmason@broadcom.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
The Broadcom Northstar Plus SoC is architected under the iProc
architecture. It has the following PLLs: ARMPLL, GENPLL, LCPLL0, all
derived from an onboard crystal.
Signed-off-by: Jon Mason <jonmason@broadcom.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Some iProc SoC clocks use a different way to control clock power, via
the PWRDWN bit in the PLL control register. Since the PLL control
register is used to access the PWRDWN bit, there is no need for the
pwr_base when this is being used. A new flag, IPROC_CLK_EMBED_PWRCTRL,
has been added to identify this usage. We can use the AON interface to
write the values to enable/disable PWRDOWN.
Signed-off-by: Jon Mason <jonmason@broadcom.com>
[sboyd@codeaurora.org: Remove useless parentheses]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
The macros that are being used to initialize the values of the clk
structures should be all caps. Find and replace all of them with their
relevant counterparts.
Signed-off-by: Jon Mason <jonmason@broadcom.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
When CONFIG_CYGNUS is set but CONFIG_COMMON_CLK_IPROC is disabled, the
following link failures are caused:
drivers/built-in.o: In function `cygnus_armpll_init':
:(.init.text+0x1d290): undefined reference to `iproc_armpll_setup'
drivers/built-in.o: In function `cygnus_genpll_clk_init':
:(.init.text+0x1d2c4): undefined reference to `iproc_pll_clk_setup'
drivers/built-in.o: In function `cygnus_lcpll0_clk_init':
:(.init.text+0x1d304): undefined reference to `iproc_pll_clk_setup'
drivers/built-in.o: In function `cygnus_mipipll_clk_init':
:(.init.text+0x1d344): undefined reference to `iproc_pll_clk_setup'
drivers/built-in.o: In function `cygnus_asiu_init':
:(.init.text+0x1d370): undefined reference to `iproc_asiu_setup'
It is fixed it by always selecting COMMON_CLK_IPROC from
ARCH_BCM_IPROC, and making COMMON_CLK_IPROC a silent option (thus
preventing it from being erroneously disabled by a user).
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jon Mason <jonmason@broadcom.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
This patch affects the clocks that use fractional ndivider in their
PLL output frequency calculation. Instead of 2^20 divide factor, the
clock's ndiv integer shift was used. Fixed the bug by replacing ndiv
integer shift with 2^20 factor.
Signed-off-by: Simran Rai <ssimran@broadcom.com>
Signed-off-by: Ray Jui <rjui@broadcom.com>
Reviewed-by: Scott Branden <sbranden@broadcom.com>
Fixes: 5fe225c105 ("clk: iproc: add initial common clock support")
Cc: <stable@vger.kernel.org> # v4.1+
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
These drivers only have runtime but no build time dependencies so can be
built for testing purposes if the Kconfig COMPILE_TEST option is enabled.
This is useful to have more build coverage and make sure that drivers are
not affected by changes that could cause build regressions.
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Scott Branden <sbranden@broadcom.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
This adds support for enabling, disabling, and setting the rate of the
audio domain clocks. It will be necessary for setting the pixel clock
for HDMI in the VC4 driver and let us write a cpufreq driver. It will
also improve compatibility with user changes to the firmware's
config.txt, since our previous fixed clocks are unaware of it.
The firmware also has support for configuring the clocks through the
mailbox channel, but the pixel clock setup by the firmware doesn't
work, and it's Raspberry Pi specific anyway. The only conflicts we
should have with the firmware would be if we made firmware calls that
result in clock management (like opening firmware V3D or ISP access,
which we don't support in upstream), or on hardware over-thermal or
under-voltage (when the firmware would rewrite PLLB to take the ARM
out of overclock). If that happens, our cached .recalc_rate() results
would be incorrect, but that's no worse than our current state where
we used fixed clocks.
The existing fixed clocks in the code are left in place to provide
backwards compatibility with old device tree files.
Signed-off-by: Eric Anholt <eric@anholt.net>
Tested-by: Martin Sperl <kernel@martin.sperl.org>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
clk-bcm2835.c predates the drivers under bcm/, but all the new BCM
drivers are going in there so let's follow them.
Signed-off-by: Eric Anholt <eric@anholt.net>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
We're removing struct clk from the clk provider API, so switch
this code to using the clk_hw based provider APIs.
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* cleanup-clk-h-includes: (62 commits)
clk: Remove clk.h from clk-provider.h
clk: h8300: Remove clk.h and clkdev.h includes
clk: at91: Include clk.h and slab.h
clk: ti: Switch clk-provider.h include to clk.h
clk: pistachio: Include clk.h
clk: ingenic: Include clk.h
clk: si570: Include clk.h
clk: moxart: Include clk.h
clk: cdce925: Include clk.h
clk: Include clk.h in clk.c
clk: zynq: Include clk.h
clk: ti: Include clk.h
clk: sunxi: Include clk.h and remove unused clkdev.h includes
clk: st: Include clk.h
clk: qcom: Include clk.h
clk: highbank: Include clk.h
clk: bcm: Include clk.h
clk: versatile: Remove clk.h and clkdev.h includes
clk: ux500: Remove clk.h and clkdev.h includes
clk: tegra: Properly include clk.h
...
Clock rates are stored in an unsigned long field, but ->determine_rate()
(which returns a rounded rate from a requested one) returns a long
value (errors are reported using negative error codes), which can lead
to long overflow if the clock rate exceed 2Ghz.
Change ->determine_rate() prototype to return 0 or an error code, and pass
a pointer to a clk_rate_request structure containing the expected target
rate and the rate constraints imposed by clk users.
The clk_rate_request structure might be extended in the future to contain
other kind of constraints like the rounding policy, the maximum clock
inaccuracy or other things that are not yet supported by the CCF
(power consumption constraints ?).
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
CC: Jonathan Corbet <corbet@lwn.net>
CC: Tony Lindgren <tony@atomide.com>
CC: Ralf Baechle <ralf@linux-mips.org>
CC: "Emilio López" <emilio@elopez.com.ar>
CC: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Tero Kristo <t-kristo@ti.com>
CC: Peter De Schrijver <pdeschrijver@nvidia.com>
CC: Prashant Gaikwad <pgaikwad@nvidia.com>
CC: Stephen Warren <swarren@wwwdotorg.org>
CC: Thierry Reding <thierry.reding@gmail.com>
CC: Alexandre Courbot <gnurou@gmail.com>
CC: linux-doc@vger.kernel.org
CC: linux-kernel@vger.kernel.org
CC: linux-arm-kernel@lists.infradead.org
CC: linux-omap@vger.kernel.org
CC: linux-mips@linux-mips.org
CC: linux-tegra@vger.kernel.org
[sboyd@codeaurora.org: Fix parent dereference problem in
__clk_determine_rate()]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Tested-by: Romain Perier <romain.perier@gmail.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
[sboyd@codeaurora.org: Folded in fix from Heiko for fixed-rate
clocks without parents or a rate determining op]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
This clock provider uses the consumer API, so include clk.h
explicitly.
Acked-by: Alex Elder <elder@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
A 32-bit variable should be type casted to 64-bit before arithmetic
operation and assigning it to a 64-bit variable
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Ray Jui <rjui@broadcom.com>
Fixes: 5fe225c105 ("clk: iproc: add initial common clock support")
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
of_property_read_string_index takes array of pointers and assign them to
strings read from device tree property. No additional memory allocation
is needed prior to calling of_property_read_string_index. In fact, since
the array of pointers will be re-assigned to other strings, any memory
that it points to prior to calling of_property_read_string_index will be
leaked
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Ray Jui <rjui@broadcom.com>
Fixes: 5fe225c105 ("clk: iproc: add initial common clock support")
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
The Broadcom Cygnus SoC is architected under the iProc architecture. It
has the following PLLs: ARMPLL, GENPLL, LCPLL0, MIPIPLL, all dervied
from an onboard crystal. Cygnus also has various ASIU clocks that are
derived directly from the onboard crystal.
Signed-off-by: Ray Jui <rjui@broadcom.com>
Reviewed-by: Scott Branden <sbranden@broadcom.com>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
This adds basic and generic support for various iProc PLLs and clocks
including the ARMPLL, GENPLL, LCPLL, MIPIPLL, and ASIU clocks.
SoCs under the iProc architecture can define their specific register
offsets and clock parameters for their PLL and clock controllers. These
parameters can be passed as arugments into the generic iProc PLL and
clock setup functions
Derived from code originally provided by Jonathan Richardson
<jonathar@broadcom.com>
Signed-off-by: Ray Jui <rjui@broadcom.com>
Reviewed-by: Scott Branden <sbranden@broadcom.com>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
This list doesn't look to be used. Let's remove it and any
associated code that would be manipulating this list. This also
silences this error:
drivers/clk/bcm/clk-kona-setup.c:24:1: warning: symbol 'ccu_list' was not declared. Should it be static?
Reviewed-by: Alex Elder <elder@linaro.org>
Cc: Tim Kryger <tim.kryger@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Now that the kernel provides DIV_ROUND_CLOSEST_ULL(), drop the internal
implementation and use the kernel one.
Signed-off-by: Javi Merino <javi.merino@arm.com>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Alex Elder <elder@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Adds a way for clock consumers to set maximum and minimum rates. This
can be used for thermal drivers to set minimum rates, or by misc.
drivers to set maximum rates to assure a minimum performance level.
Changes the signature of the determine_rate callback by adding the
parameters min_rate and max_rate.
Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
[sboyd@codeaurora.org: set req_rate in __clk_init]
Signed-off-by: Michael Turquette <mturquette@linaro.org>
[mturquette@linaro.org: min/max rate for sun6i_ahb1_clk_determine_rate
migrated clk-private.h changes to clk.c]
This is in preparation for clock providers to not have to deal with struct clk.
Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
Implement the clk->determine_rate method for Broadcom Kona peripheral
clocks. This allows a peripheral clock to be re-parented in order to
satisfy a rate change request. This takes the place of the previous
kona_peri_clk_round_rate() functionality, though that function remains
because it is used by the new one.
The parent clock that allows the peripheral clock to produce a rate
closest to the one requested is the one selected, though the current
parent is used by default.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
Define the set of CCUs and provided clocks sufficient to satisfy the
needs of all the existing clock references for BCM21664. Replace
the "fake" fixed-rate clocks used previously with "real" ones.
Note that only the minimal set of these clocks and CCUs is defined
here. More clock definitions will need to be added as required by
the addition of additional drivers.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
The Broadcom 281xx clock code uses a #define for the compatible
string for it's clock control units (CCUs). Rather than defining
those in the C source file, define them in the header file that's
shared by both the code and the device tree source file (along with
all the clock ids).
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
Add support for clock gate hysteresis control. For now, if it's
defined for a clock, it's enabled.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
Add support for CCU policy engine control, and also for setting the
mask bits for bus clocks that require a policy change to get
activated. This includes adding validity checking framework for
CCUs, to validate the policy fields if defined.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
Rather than "manually" setting up each CCU's clock entries at run
time, define a flexible array of generic Kona clock structures
within the CCU structure itself. Each of these entries contains
generic kona clock information (like its CCU pointer and clock
framework initialization data). Each also has a pointer to a
structure contianing clock type-dependent initialization data
(like register definitions).
Since we'll iterate over these arrays we need to be sure they have
slots for all potential clock index values. (E.g. for the root CCU
we must have at least BCM281XX_ROOT_CCU_CLOCK_COUNT slots.) To
ensure this we always define an extra entry and fill it using the
special initializer LAST_KONA_CLK.
Just about everything we need to know about a clock can be defined
statically. As a result, kona_clk_setup() can be changed to take
just a kona_clk structure as its argument, and peri_clk_setup() can
be simplified. With the information pre-defined we are also able
to handle most clock setup genericially. We can do away with the
CCU-specific callback functions that previously were needed to set
up the entries in CCU's clock array.
Move the definition of the ccu_data structure down in "clk-kona.h"
to avoid a forward dependency.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
We know up front how many CCU's we'll support, so there's no need to
allocate their data structures dynamically. Define a macro
KONA_CCU_COMMON() to simplify the initialization of many of the
fields in a ccu_data structure. Pass the address of a statically
defined CCU structure to kona_dt_ccu_setup() rather than having that
function allocate one.
We also know at build time how many clocks a given CCU will provide,
though the number of of them for each CCU is different. Record the
number of clocks we need in the CCU's clk_onecell_data struct
(which is used when we register the CCU with the common clock code
as a clock provider). Rename that struct field "clk_data" (because
"data" alone gets a little confusing).
Use the known clock count to move the allocation of each CCU's
clocks array into ccu_clks_setup() rather than having each CCU's
setup callback function do it.
(The real motivation behind all of this is that we'll be doing some
static initialization of some additional CCU-specific data soon.)
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
As I developed the bcm281xx clock code I understood there were
restrictions on device tree "compatible" strings names, and as a
result "bcm11351" was used in places despite the part family being
more properly called "bcm281xx". This can be a little confusing.
In some cases I went to far and things using "bcm11351" when that
was not necessary.
This patch remedies this. It renames the symbol used to define the
"compatible" string (but not its value) so it uses "BCM281XX".
Similarly, the name names provided to the CLK_OF_DECLARE() macro
are changed, hoping to minimize the number of places that the
confusing "11351" string is used.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
Use the init_data.name field to hold the name of a Kona clock rather
than duplicating it.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
The Broadcom Kona clock code, as originally written, made use of
unnamed union and struct fields. This is a feature present in C11,
and is a GNU extension otherwise. It worked very well for me.
Unfortunately, Russell King reported that this feature was not
supported in a build environment he used, which meant attempting
to build this code failed spectacularly.
Add names to these unnamed fields, and update the code accordingly.
Reported-by: Russell King <linux@arm.linux.org.uk>
Tested-by: Markus Mayer <markus.mayer@linaro.org>
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
Add the CLK_IGNORE_UNUSED flag when setting up a peripheral clock.
This prevents unused clocks from getting disabled, and by doing
this we can use the common clock code even before we've resolved
all the spots that need to get a reference to their clock.
Signed-off-by: Alex Elder <elder@linaro.org>
Reviewed-by: Matt Porter <mporter@linaro.org>
Acked-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Matt Porter <mporter@linaro.org>
Add code for device tree support of clocks in the BCM281xx family of
SoCs. Machines in this family use peripheral clocks implemented by
"Kona" clock control units (CCUs). (Other Broadcom SoC families use
Kona style CCUs as well, but support for them is not yet upstream.)
A BCM281xx SoC has multiple CCUs, each of which manages a set of
clocks on the SoC. A Kona peripheral clock is composite clock that
may include a gate, a parent clock multiplexor, and zero, one
or two dividers. There is a variety of gate types, and many gates
implement hardware-managed gating (often called "auto-gating").
Most dividers divide their input clock signal by an integer value
(one or more). There are also "fractional" dividers which allow
division by non-integer values. To accomodate such dividers,
clock rates and dividers are generally maintained by the code in
"scaled" form, which allows integer and fractional dividers to
be handled in a uniform way.
If present, the gate for a Kona peripheral clock must be enabled
when a change is made to its multiplexor or one of its dividers.
Additionally, dividers and multiplexors have trigger registers which
must be used whenever the divider value or selected parent clock is
changed. The same trigger is often used for a divider and
multiplexor, and a BCM281xx peripheral clock occasionally has two
triggers.
The gate, dividers, and parent clock selector are treated in this
code as "components" of a peripheral clock. Their functionality is
implemented directly--e.g. the common clock framework gate
implementation is not used for a Kona peripheral clock gate. (This
has being considered though, and the intention is to evolve this
code to leverage common code as much as possible.)
The source code is divided into three general portions:
drivers/clk/bcm/clk-kona.h
drivers/clk/bcm/clk-kona.c
These implement the basic Kona clock functionality,
including the clk_ops methods and various routines to
manipulate registers and interpret their values. This
includes some functions used to set clocks to a desired
initial state (though this feature is only partially
implemented here).
drivers/clk/bcm/clk-kona-setup.c
This contains generic run-time initialization code for
data structures representing Kona CCUs and clocks. This
encapsulates the clock structure initialization that can't
be done statically. Note that there is a great deal of
validity-checking code here, making explicit certain
assumptions in the code. This is mostly useful for adding
new clock definitions and could possibly be disabled for
production use.
drivers/clk/bcm/clk-bcm281xx.c
This file defines the specific CCUs used by BCM281XX family
SoCs, as well as the specific clocks implemented by each.
It declares a device tree clock match entry for each CCU
defined.
include/dt-bindings/clock/bcm281xx.h
This file defines the selector (index) values used to
identify a particular clock provided by a CCU. It consists
entirely of C preprocessor constants, to be used by both the
C source and device tree source files.
Signed-off-by: Alex Elder <elder@linaro.org>
Reviewed-by: Tim Kryger <tim.kryger@linaro.org>
Reviewed-by: Matt Porter <mporter@linaro.org>
Acked-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Matt Porter <mporter@linaro.org>
Martin Sperl