The MBUS serves as the main data bus for various DMA masters in the
system. If its clock is not enabled, the DMA operations will stall,
leading to the peripherals stalling or timing out. This has been
observed as USB or MMC hosts timing out waiting for transactions
when the clock is automatically disabled by the CCF due to it not
being used.
Mark the clock as critical so that it never gets disabled.
Fixes: 74b0443a0d ("clk: sunxi-ng: a523: add system mod clocks")
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Link: https://patch.msgid.link/20250607135029.2085140-1-wens@kernel.org
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Allwinner SoCs do not contain a separate reset controller, instead the
reset lines for the various devices are integrated into the "BGR" (Bus
Gate / Reset) registers, for each device group: one for all UARTs, one
for all SPI interfaces, and so on.
The Allwinner CCU driver also doubles as a reset provider, and since the
reset lines are indeed just single bits in those BGR register, we can
represent them easily in an array of structs, just containing the
register offset and the bit number.
Add the location of the reset bits for all devices in the A523/T527
SoCs, using the existing sunxi CCU infrastructure.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Link: https://patch.msgid.link/20250307002628.10684-14-andre.przywara@arm.com
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Add the various bus clock gates that control access to the devices'
register interface.
These clocks are each just one bit, typically the lower bits in some "BGR"
(Bus Gate / Reset) registers, for each device group: one for all UARTs,
one for all SPI interfaces, and so on.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Link: https://patch.msgid.link/20250307002628.10684-13-andre.przywara@arm.com
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Add the remaining mod clocks, driving various parts of the SoC: the "LEDC"
LED controller, the "CSI" camera interface, the "ISP" image processor,
the DSP clock, and the "fanout" clocks, which allow to put clock signals
on external pins.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Link: https://patch.msgid.link/20250307002628.10684-12-andre.przywara@arm.com
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Add the clocks driving the USB subsystem: this just covers the two
clocks creating the 12 MHz rate for the OHCI (USB 1.x) device. The rest
of the USB clocks are either gate clocks (added later) or created
internal to the USB IP.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Link: https://patch.msgid.link/20250307002628.10684-11-andre.przywara@arm.com
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Add the clocks driving what the user manual summarises under "interface"
devices: raw NAND flash, MMC, SPI, EMAC, "IR" infrared, and the "GPADC"
general purpose analogue/digital converter.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Link: https://patch.msgid.link/20250307002628.10684-10-andre.przywara@arm.com
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Add the clocks driving some core system related subsystems of the SoC:
the "CE" crypto engine, the high speed timers, the DRAM and the associated
MBUS clock, and the PCIe clock.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Link: https://patch.msgid.link/20250307002628.10684-9-andre.przywara@arm.com
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Add the clocks driving the various video subsystems of the SoC: the "DE"
display engine, the "DI" deinterlacer, the "G2D" 2D graphics system, the
Mali "GPU", the "VE" video engine, its associated IOMMU, as well as the
clocks for the various video output drivers (HDMI, DP, LCDs).
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Link: https://patch.msgid.link/20250307002628.10684-8-andre.przywara@arm.com
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Add the basic bus clocks for the Allwinner A523 and T527 SoCs.
This covers the AHB, APB0 and APB1 clocks. Linux is not supposed to
change those clocks, but they are needed as parents for many other mod
clocks.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Link: https://patch.msgid.link/20250307002628.10684-7-andre.przywara@arm.com
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Add the PLL clocks of the main CCU of the Allwinner A523 and T527 SoCs.
The clocks were modelled after the A523 and T527 manual, and double
checked by writing all 1's into the respective register, to spot all
implemented bits.
The PLL and mod clocks for the two CPU clusters and the DSU are part of
a separate CCU, also most audio clocks are collected in a DSP CCU, so
both of these clock groups are missing from this driver.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Link: https://patch.msgid.link/20250307002628.10684-6-andre.przywara@arm.com
Signed-off-by: Chen-Yu Tsai <wens@csie.org>