Commit graph

76 commits

Author SHA1 Message Date
Eric Anholt
67615c588a clk: bcm2835: Skip PLLC clocks when deciding on a new clock parent
If the firmware had set up a clock to source from PLLC, go along with
it.  But if we're looking for a new parent, we don't want to switch it
to PLLC because the firmware will force PLLC (and thus the AXI bus
clock) to different frequencies during over-temp/under-voltage,
without notification to Linux.

On my system, this moves the Linux-enabled HDMI state machine and DSI1
escape clock over to plld_per from pllc_per.  EMMC still ends up on
pllc_per, because the firmware had set it up to use that.

Signed-off-by: Eric Anholt <eric@anholt.net>
Fixes: 41691b8862 ("clk: bcm2835: Add support for programming the audio domain clocks")
Acked-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-09-07 08:57:44 -07:00
Eric Anholt
9e400c5cc5 clk: bcm2835: Mark the CM SDRAM clock's parent as critical
While the SDRAM is being driven by its dedicated PLL most of the time,
there is a little loop running in the firmware that periodically turns
on the CM SDRAM clock (using its pre-initialized parent) and switches
SDRAM to using the CM clock to do PVT recalibration.

This avoids system hangs if we choose SDRAM's parent for some other
clock, then disable that clock.

Signed-off-by: Eric Anholt <eric@anholt.net>
Acked-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-09-07 08:57:35 -07:00
Eric Anholt
eddcbe8398 clk: bcm2835: Mark GPIO clocks enabled at boot as critical
These divide off of PLLD_PER and are used for the ethernet and wifi
PHYs source PLLs.  Neither of them is currently represented by a phy
device that would grab the clock for us.

This keeps other drivers from killing the networking PHYs when they
disable their own clocks and trigger PLLD_PER's refcount going to 0.

Signed-off-by: Eric Anholt <eric@anholt.net>
Acked-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-09-07 08:57:22 -07:00
Eric Anholt
e69fdcca83 clk: bcm2835: Mark the VPU clock as critical
The VPU clock is also the clock for our AXI bus, so we really can't
disable it.  This might have happened during boot if, for example,
uart1 (aux_uart clock) probed and was then disabled before the other
consumers of the VPU clock had probed.

Signed-off-by: Eric Anholt <eric@anholt.net>
Acked-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-09-07 08:57:09 -07:00
Eric Anholt
e708b383f4 clk: bcm2835: Fix PLL poweron
In poweroff, we set the reset bit and the power down bit, but only
managed to unset the reset bit for poweron.  This meant that if HDMI
did -EPROBE_DEFER after it had grabbed its clocks, we'd power down the
PLLH (that had been on at boot time) and never recover.

Signed-off-by: Eric Anholt <eric@anholt.net>
Fixes: 41691b8862 ("clk: bcm2835: Add support for programming the audio domain clocks")
Cc: stable@vger.kernel.org
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-04-19 18:56:17 -07:00
Eric Anholt
286259ef4b clk: bcm2835: Fix compiler warnings on 64-bit builds
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-04-19 18:56:16 -07:00
Martin Sperl
d3d6f15fd3 clk: bcm2835: add missing osc and per clocks
Add AVE0, DFT, GP0, GP1, GP2, SLIM, SMI, TEC, DPI, CAM0, CAM1, DSI0E,
and DSI1E.  PULSE is not added because it has an extra divider.

Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Eric Anholt <eric@anholt.net>
2016-03-17 10:42:17 -07:00
Martin Sperl
728436956a clk: bcm2835: add missing PLL clock dividers
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Eric Anholt <eric@anholt.net>
2016-03-17 10:42:17 -07:00
Martin Sperl
33b689600f clk: bcm2835: enable management of PCM clock
Enable the PCM clock in the SOC, which is used by the
bcm2835-i2s driver.

Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Eric Anholt <eric@anholt.net>
2016-03-17 10:42:17 -07:00
Martin Sperl
3b15afefbe clk: bcm2835: reorganize bcm2835_clock_array assignment
Reorganize bcm2835_clock_array so that there is no more
need for separate bcm2835_*_data structures to be defined.
Instead the required structures are generated inline via
helper macros.

To allow this to also work for pll alone it was required that
the parent_pll was changed from a pointer to bcm2835_pll_data
to the name of the pll instead.

Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Eric Anholt <eric@anholt.net>
2016-03-17 10:42:17 -07:00
Martin Sperl
56eb3a2ed9 clk: bcm2835: remove use of BCM2835_CLOCK_COUNT in driver
As the use of BCM2835_CLOCK_COUNT in
include/dt-bindings/clock/bcm2835.h is frowned upon as
it needs to get modified every time a new clock gets introduced
this patch changes the clk-bcm2835 driver to use a different
scheme for registration of clocks and pll, so that there
is no more need for BCM2835_CLOCK_COUNT to be defined.

Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Eric Anholt <eric@anholt.net>
2016-03-17 10:42:17 -07:00
Martin Sperl
96bf9c69d5 clk: bcm2835: expose raw clock-registers via debugfs
For debugging purposes under some circumstance
it helps to be able to see the actual clock registers.

E.g: when looking at the clock divider it is helpful to
see what the actual clock divider is.

This patch exposes all the clock registers specific to each
clock/pll/pll-divider via debugfs.

Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Acked-by: Eric Anholt <eric@anholt.net>
2016-03-17 10:42:17 -07:00
Martin Sperl
6e1e60dace clk: bcm2835: clean up coding style issues
Fix all the checkpatch complaints for clk-bcm2835.c

Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
2016-03-17 10:42:17 -07:00
Martin Sperl
959ca92a32 clk: bcm2835: correctly enable fractional clock support
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>
2016-03-17 10:42:17 -07:00
Martin Sperl
997f16bd5d clk: bcm2835: divider value has to be 1 or more
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>
2016-03-17 10:42:17 -07:00
Martin Sperl
ec36a5c668 clk: bcm2835: add locking to pll*_on/off methods
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>
2016-03-17 10:42:17 -07:00
Martin Sperl
6727f086cf clk: bcm2835: pll_off should only update CM_PLL_ANARST
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>
2016-03-17 10:42:17 -07:00
Stephen Boyd
bd41aa6773 clk: bcm: Remove CLK_IS_ROOT
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>
2016-03-02 17:42:41 -08:00
Martin Sperl
2103a21561 clk: bcm2835: added missing clock register definitions
Added missing CTRL and DIV clock register definitions for:
PCM, SLIM, TCNT, TEC, TD0, TD1

Register information taken from:
https://rawgit.com/msperl/rpi-registers/master/rpi-registers.html#CM
which extracted the information from the header files shared by
Broadcom/rpi foundation in this file:
http://www.broadcom.com/docs/support/videocore/Brcm_Android_ICS_Graphics_Stack.tar.gz

Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2016-02-25 16:07:59 -08:00
Eric Anholt
79c1e2fc2c clk: bcm2835: Reuse CLK_DIVIDER_MAX_AT_ZERO for recalc_rate()
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>
2016-02-16 12:30:09 -08:00
Eric Anholt
773b3966dd clk: bcm2835: Fix setting of PLL divider clock rates
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>
2016-02-16 12:30:07 -08:00
Remi Pommarel
cfbab8fbab clk: bcm2835: Add PWM clock support
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>
2015-12-24 20:38:38 -08:00
Remi Pommarel
6d18b8adbe clk: bcm2835: Support for clock parent selection
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>
2015-12-24 20:38:30 -08:00
Remi Pommarel
9c95b32ca0 clk: bcm2835: add a round up ability to the clock divisor
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>
2015-12-24 20:38:06 -08:00
Eric Anholt
41691b8862 clk: bcm2835: Add support for programming the audio domain clocks
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>
2015-10-12 11:32:02 -07:00
Eric Anholt
4f61d8e220 clk: bcm2835: Move under bcm/ with other Broadcom SoC clk drivers.
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>
2015-10-01 17:12:03 -07:00
Renamed from drivers/clk/clk-bcm2835.c (Browse further)