The pll1_d8 clock is enabled by the boot loader, and is ultimately a
parent for numerous clocks, including those used by APB and AXI buses.
Guodong Xu discovered that this clock got disabled while responding to
getting -EPROBE_DEFER when requesting a reset controller.
The needed clock (CLK_DMA, along with its parents) had already been
enabled. To respond to the probe deferral return, the CLK_DMA clock
was disabled, and this led to parent clocks also reducing their enable
count. When the enable count for pll1_d8 was decremented it became 0,
which caused it to be disabled. This led to a system hang.
Marking that clock critical resolves this by preventing it from being
disabled.
Define a new macro CCU_FACTOR_GATE_DEFINE() to allow clock flags to
be supplied for a CCU_FACTOR_GATE clock.
Fixes: 1b72c59db0 ("clk: spacemit: Add clock support for SpacemiT K1 SoC")
Signed-off-by: Alex Elder <elder@riscstar.com>
Tested-by: Guodong Xu <guodong@riscstar.com>
Reviewed-by: Haylen Chu <heylenay@4d2.org>
Link: https://lore.kernel.org/r/20250612224856.1105924-1-elder@riscstar.com
Signed-off-by: Yixun Lan <dlan@gentoo.org>
Three CCUs on the SpacemiT K1 SoC implement only resets, not clocks.
Define the CCU data for these resets so their auxiliary devices get
created.
Signed-off-by: Alex Elder <elder@riscstar.com>
Reviewed-by: Yixun Lan <dlan@gentoo.org>
Link: https://lore.kernel.org/r/20250702113709.291748-5-elder@riscstar.com
Signed-off-by: Yixun Lan <dlan@gentoo.org>
Add a new reset_name field to the spacemit_ccu_data structure. If it is
non-null, the CCU implements a reset controller, and the name will be
used in the name for the auxiliary device that implements it.
Define a new type to hold an auxiliary device as well as the regmap
pointer that will be needed by CCU reset controllers. Set up code to
initialize and add an auxiliary device for any CCU that implements reset
functionality.
Make it optional for a CCU to implement a clock controller. This
doesn't apply to any of the existing CCUs but will for some new ones
that will be added soon.
Signed-off-by: Alex Elder <elder@riscstar.com>
Reviewed-by: Haylen Chu <heylenay@4d2.org>
Reviewed-by: Yixun Lan <dlan@gentoo.org>
Link: https://lore.kernel.org/r/20250702113709.291748-4-elder@riscstar.com
Signed-off-by: Yixun Lan <dlan@gentoo.org>
Move the definitions of register offsets and fields used by the SpacemiT
K1 SoC CCUs into a separate header file, so that they can be shared by
the reset driver that will be found under drivers/reset.
Signed-off-by: Alex Elder <elder@riscstar.com>
Reviewed-by: Haylen Chu <heylenay@4d2.org>
Reviewed-by: Yixun Lan <dlan@gentoo.org>
Link: https://lore.kernel.org/r/20250702113709.291748-3-elder@riscstar.com
Signed-off-by: Yixun Lan <dlan@gentoo.org>
The control register for TWSI8 clocks, APBC_TWSI8_CLK_RST, contains mux
selection bits, reset assertion bit and enable bits for function and bus
clocks. It has a quirk that reading always results in zero.
As a workaround, let's hardcode the mux value as zero to select
pll1_d78_31p5 as parent and treat twsi8_clk as a gate, whose enable mask
is combined from the real bus and function clocks to avoid the
write-only register being shared between two clk_hws, in which case
updates of one clk_hw zero the other's bits.
With a 1:1 factor serving as placeholder for the bus clock, the I2C-8
controller could be brought up, which is essential for boards attaching
power-management chips to it.
Signed-off-by: Haylen Chu <heylenay@4d2.org>
Reviewed-by: Alex Elder <elder@riscstar.com>
Reviewed-by: Yixun Lan <dlan@gentoo.org>
Link: https://lore.kernel.org/r/20250416135406.16284-5-heylenay@4d2.org
Signed-off-by: Yixun Lan <dlan@gentoo.org>
The clock tree of K1 SoC contains three main types of clock hardware
(PLL/DDN/MIX) and has control registers split into several multifunction
devices: APBS (PLLs), MPMU, APBC and APMU.
All register operations are done through regmap to ensure atomicity
between concurrent operations of clock driver and reset,
power-domain driver that will be introduced in the future.
Signed-off-by: Haylen Chu <heylenay@4d2.org>
Reviewed-by: Alex Elder <elder@riscstar.com>
Reviewed-by: Inochi Amaoto <inochiama@outlook.com>
Reviewed-by: Yixun Lan <dlan@gentoo.org>
Link: https://lore.kernel.org/r/20250416135406.16284-4-heylenay@4d2.org
Signed-off-by: Yixun Lan <dlan@gentoo.org>
