clk: microchip: fix potential UAF in auxdev release callback

Similar to commit 1c11289b34ab ("peci: cpu: Fix use-after-free in
adev_release()"), the auxiliary device is not torn down in the correct

clk: microchip: fix potential UAF in auxdev release callback

Similar to commit 1c11289b34ab ("peci: cpu: Fix use-after-free in
adev_release()"), the auxiliary device is not torn down in the correct
order. If auxiliary_device_add() fails, the release callback will be
called twice, resulting in a UAF. Due to timing, the auxdev code in this
driver "took inspiration" from the aforementioned commit, and thus its
bugs too!

Moving auxiliary_device_uninit() to the unregister callback instead
avoids the issue.

CC: stable@vger.kernel.org
Fixes: b56bae2dd6fd ("clk: microchip: mpfs: add reset controller")
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230413-critter-synopsis-dac070a86cb4@spud
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

show more ...

clk: microchip: mpfs: remove MODULE_LICENSE in non-modules

Since commit 8b41fc4454e ("kbuild: create modules.builtin without
Makefile.modbuiltin or tristate.conf"), MODULE_LICENSE declarations
are u

clk: microchip: mpfs: remove MODULE_LICENSE in non-modules

Since commit 8b41fc4454e ("kbuild: create modules.builtin without
Makefile.modbuiltin or tristate.conf"), MODULE_LICENSE declarations
are used to identify modules. As a consequence, uses of the macro
in non-modules will cause modprobe to misidentify their containing
object file as a module when it is not (false positives), and modprobe
might succeed rather than failing with a suitable error message.

So remove it in the files in this commit, none of which can be built as
modules.

Signed-off-by: Nick Alcock <nick.alcock@oracle.com>
Suggested-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: linux-modules@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: Hitomi Hasegawa <hasegawa-hitomi@fujitsu.com>
Cc: Conor Dooley <conor.dooley@microchip.com>
Cc: Daire McNamara <daire.mcnamara@microchip.com>
Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: linux-riscv@lists.infradead.org
Cc: linux-clk@vger.kernel.org
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>

show more ...

clk: microchip: mpfs: update module authorship & licencing

Padmarao wrote the driver in its original, pre upstream form.
Daire & myself have been responsible for getting it upstreamable and
subseque

clk: microchip: mpfs: update module authorship & licencing

Padmarao wrote the driver in its original, pre upstream form.
Daire & myself have been responsible for getting it upstreamable and
subsequent development.
Move Daire out of the blurb & into a MODULE_AUTHOR entry & add entries
for myself and Padmarao.

While we are at it, convert the MODULE_LICENSE field to its preferred
form of "GPL".

Reviewed-by: Daire McNamara <daire.mcnamara@microchip.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Link: https://lore.kernel.org/r/20220909123123.2699583-15-conor.dooley@microchip.com

show more ...

clk: microchip: mpfs: convert periph_clk to clk_gate

With the reset code moved to the recently added reset controller, there
is no need for custom ops any longer. Remove the custom ops and the
custo

clk: microchip: mpfs: convert periph_clk to clk_gate

With the reset code moved to the recently added reset controller, there
is no need for custom ops any longer. Remove the custom ops and the
custom struct by converting to a clk_gate.

Reviewed-by: Daire McNamara <daire.mcnamara@microchip.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Link: https://lore.kernel.org/r/20220909123123.2699583-14-conor.dooley@microchip.com

show more ...

clk: microchip: mpfs: convert cfg_clk to clk_divider

The cfg_clk struct is now just a redefinition of the clk_divider struct
with custom implentations of the ops, that implement an extra level of
re

clk: microchip: mpfs: convert cfg_clk to clk_divider

The cfg_clk struct is now just a redefinition of the clk_divider struct
with custom implentations of the ops, that implement an extra level of
redirection. Remove the custom struct and replace it with clk_divider.

Reviewed-by: Daire McNamara <daire.mcnamara@microchip.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Link: https://lore.kernel.org/r/20220909123123.2699583-13-conor.dooley@microchip.com

show more ...

clk: microchip: mpfs: delete 2 line mpfs_clk_register_foo()

The register functions are now comprised of only a single operation
each and no longer add anything to the driver. Delete them.

Reviewed-

clk: microchip: mpfs: delete 2 line mpfs_clk_register_foo()

The register functions are now comprised of only a single operation
each and no longer add anything to the driver. Delete them.

Reviewed-by: Daire McNamara <daire.mcnamara@microchip.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Link: https://lore.kernel.org/r/20220909123123.2699583-12-conor.dooley@microchip.com

show more ...

clk: microchip: mpfs: simplify control reg access

The control reg addresses are known when the clocks are registered, so
we can, instead of assigning a base pointer to the structs, assign the
contro

clk: microchip: mpfs: simplify control reg access

The control reg addresses are known when the clocks are registered, so
we can, instead of assigning a base pointer to the structs, assign the
control reg addresses directly. Accordingly, remove the interim
variables used during reads/writes to those registers.

Reviewed-by: Daire McNamara <daire.mcnamara@microchip.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Link: https://lore.kernel.org/r/20220909123123.2699583-11-conor.dooley@microchip.com

show more ...

clk: microchip: mpfs: move id & offset out of clock structs

The id and offset are the only thing differentiating the clock structs
from "regular" clock structures. On the pretext of converting to mo

clk: microchip: mpfs: move id & offset out of clock structs

The id and offset are the only thing differentiating the clock structs
from "regular" clock structures. On the pretext of converting to more
normal structures, move the id and offset out of the clock structs and
into the hw structs instead.

Reviewed-by: Daire McNamara <daire.mcnamara@microchip.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Link: https://lore.kernel.org/r/20220909123123.2699583-10-conor.dooley@microchip.com

show more ...

clk: microchip: mpfs: add MSS pll's set & round rate

The MSS pll is not a fixed frequency clock, so add set() & round_rate()
support.
Control is limited to a 7 bit output divider as other devices on

clk: microchip: mpfs: add MSS pll's set & round rate

The MSS pll is not a fixed frequency clock, so add set() & round_rate()
support.
Control is limited to a 7 bit output divider as other devices on the
FPGA occupy the other three outputs of the PLL & prevent changing
the multiplier.

Reviewed-by: Daire McNamara <daire.mcnamara@microchip.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Link: https://lore.kernel.org/r/20220909123123.2699583-9-conor.dooley@microchip.com

show more ...

clk: microchip: mpfs: add reset controller

Add a reset controller to PolarFire SoC's clock driver. This reset
controller is registered as an aux device and read/write functions
exported to the drive

clk: microchip: mpfs: add reset controller

Add a reset controller to PolarFire SoC's clock driver. This reset
controller is registered as an aux device and read/write functions
exported to the drivers namespace so that the reset controller can
access the peripheral device reset register.

Reviewed-by: Daire McNamara <daire.mcnamara@microchip.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Link: https://lore.kernel.org/r/20220909123123.2699583-5-conor.dooley@microchip.com

show more ...

clk: microchip: mpfs: make the rtc's ahb clock critical

The onboard RTC's AHB bus clock must be kept running as the RTC will
stop & lose track of time if the AHB interface clock is disabled.

Fixes:

clk: microchip: mpfs: make the rtc's ahb clock critical

The onboard RTC's AHB bus clock must be kept running as the RTC will
stop & lose track of time if the AHB interface clock is disabled.

Fixes: 635e5e73370e ("clk: microchip: Add driver for Microchip PolarFire SoC")
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Link: https://lore.kernel.org/r/20220909123123.2699583-3-conor.dooley@microchip.com

show more ...

clk: microchip: mpfs: fix clk_cfg array bounds violation

There is an array bounds violation present during clock registration,
triggered by current code by only specific toolchains. This seems to
fa

clk: microchip: mpfs: fix clk_cfg array bounds violation

There is an array bounds violation present during clock registration,
triggered by current code by only specific toolchains. This seems to
fail gracefully in v6.0-rc1, using a toolchain build from the riscv-
gnu-toolchain repo and with clang-15, and life carries on. While
converting the driver to use standard clock structs/ops, kernel panics
were seen during boot when built with clang-15:

[ 0.581754] Unable to handle kernel NULL pointer dereference at virtual address 00000000000000b1
[ 0.591520] Oops [#1]
[ 0.594045] Modules linked in:
[ 0.597435] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.0.0-rc1-00011-g8e1459cf4eca #1
[ 0.606188] Hardware name: Microchip PolarFire-SoC Icicle Kit (DT)
[ 0.613012] epc : __clk_register+0x4a6/0x85c
[ 0.617759] ra : __clk_register+0x49e/0x85c
[ 0.622489] epc : ffffffff803faf7c ra : ffffffff803faf74 sp : ffffffc80400b720
[ 0.630466] gp : ffffffff810e93f8 tp : ffffffe77fe60000 t0 : ffffffe77ffb3800
[ 0.638443] t1 : 000000000000000a t2 : ffffffffffffffff s0 : ffffffc80400b7c0
[ 0.646420] s1 : 0000000000000001 a0 : 0000000000000001 a1 : 0000000000000000
[ 0.654396] a2 : 0000000000000001 a3 : 0000000000000000 a4 : 0000000000000000
[ 0.662373] a5 : ffffffff803a5810 a6 : 0000000200000022 a7 : 0000000000000006
[ 0.670350] s2 : ffffffff81099d48 s3 : ffffffff80d6e28e s4 : 0000000000000028
[ 0.678327] s5 : ffffffff810ed3c8 s6 : ffffffff810ed3d0 s7 : ffffffe77ffbc100
[ 0.686304] s8 : ffffffe77ffb1540 s9 : ffffffe77ffb1540 s10: 0000000000000008
[ 0.694281] s11: 0000000000000000 t3 : 00000000000000c6 t4 : 0000000000000007
[ 0.702258] t5 : ffffffff810c78c0 t6 : ffffffe77ff88cd0
[ 0.708125] status: 0000000200000120 badaddr: 00000000000000b1 cause: 000000000000000d
[ 0.716869] [<ffffffff803fb892>] devm_clk_hw_register+0x62/0xaa
[ 0.723420] [<ffffffff80403412>] mpfs_clk_probe+0x1e0/0x244

In v6.0-rc1 and later, this issue is visible without the follow on
patches doing the conversion using toolchains provided by our Yocto
meta layer too.

It fails on "clk_periph_timer" - which uses a different parent, that it
tries to find using the macro:
\#define PARENT_CLK(PARENT) (&mpfs_cfg_clks[CLK_##PARENT].cfg.hw)

If parent is RTCREF, so the macro becomes: &mpfs_cfg_clks[33].cfg.hw
which is well beyond the end of the array. Amazingly, builds with GCC
11.1 see no problem here, booting correctly and hooking the parent up
etc. Builds with clang-15 do not, with the above panic.

Change the macro to use specific offsets depending on the parent rather
than the dt-binding's clock IDs.

Fixes: 1c6a7ea32b8c ("clk: microchip: mpfs: add RTCREF clock control")
CC: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Link: https://lore.kernel.org/r/20220909123123.2699583-2-conor.dooley@microchip.com

show more ...

clk: microchip: mpfs: add RTCREF clock control

The reference clock used by the PolarFire SoC's onboard rtc was missing
from the clock driver. Add this clock at the "config" clock level, with
the ext

clk: microchip: mpfs: add RTCREF clock control

The reference clock used by the PolarFire SoC's onboard rtc was missing
from the clock driver. Add this clock at the "config" clock level, with
the external reference clock as its parent.

Fixes: 635e5e73370e ("clk: microchip: Add driver for Microchip PolarFire SoC")
Reviewed-by: Daire McNamara <daire.mcnamara@microchip.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220413075835.3354193-9-conor.dooley@microchip.com
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

show more ...

clk: microchip: mpfs: re-parent the configurable clocks

Currently the mpfs clock driver uses a reference clock called the
"msspll", set in the device tree, as the parent for the cpu/axi/ahb
(config)

clk: microchip: mpfs: re-parent the configurable clocks

Currently the mpfs clock driver uses a reference clock called the
"msspll", set in the device tree, as the parent for the cpu/axi/ahb
(config) clocks. The frequency of the msspll is determined by the FPGA
bitstream & the bootloader configures the clock to match the bitstream.
The real reference is provided by a 100 or 125 MHz off chip oscillator.

However, the msspll clock is not actually the parent of all clocks on
the system - the reference clock for the rtc/mtimer actually has the
off chip oscillator as its parent.

In order to fix this, add support for reading the configuration of the
msspll & reparent the "config" clocks so that they are derived from
this clock rather than the reference in the device tree.

Fixes: 635e5e73370e ("clk: microchip: Add driver for Microchip PolarFire SoC")
Reviewed-by: Daire McNamara <daire.mcnamara@microchip.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220413075835.3354193-8-conor.dooley@microchip.com
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

show more ...

clk: microchip: mpfs: mark CLK_ATHENA as critical

CLK_ATHENA is another fabric interconnect and should be marked as critical
as with FIC0-3, since disabling it will cause part of the fabric to go
in

clk: microchip: mpfs: mark CLK_ATHENA as critical

CLK_ATHENA is another fabric interconnect and should be marked as critical
as with FIC0-3, since disabling it will cause part of the fabric to go
into reset.

Fixes: 635e5e73370e ("clk: microchip: Add driver for Microchip PolarFire SoC")
Reviewed-by: Daire McNamara <daire.mcnamara@microchip.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220413075835.3354193-3-conor.dooley@microchip.com
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

show more ...

clk: microchip: mpfs: fix parents for FIC clocks

The fabric interconnects are on the AXI bus not AHB.
Update their parent clocks to fix this.

Fixes: 635e5e73370e ("clk: microchip: Add driver for Mi

clk: microchip: mpfs: fix parents for FIC clocks

The fabric interconnects are on the AXI bus not AHB.
Update their parent clocks to fix this.

Fixes: 635e5e73370e ("clk: microchip: Add driver for Microchip PolarFire SoC")
Reviewed-by: Daire McNamara <daire.mcnamara@microchip.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220413075835.3354193-2-conor.dooley@microchip.com
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

show more ...

clk: microchip: mpfs: don't reset disabled peripherals

The current clock driver for PolarFire SoC puts the hardware behind
"periph" clocks into reset if their clock is disabled. CONFIG_PM was
recent

clk: microchip: mpfs: don't reset disabled peripherals

The current clock driver for PolarFire SoC puts the hardware behind
"periph" clocks into reset if their clock is disabled. CONFIG_PM was
recently added to the riscv defconfig and exposed issues caused by this
behaviour, where the Cadence GEM was being put into reset between its
bringup & the PHY bringup:

https://lore.kernel.org/linux-riscv/9f4b057d-1985-5fd3-65c0-f944161c7792@microchip.com/

Fix this (for now) by removing the reset from mpfs_periph_clk_disable.

Fixes: 635e5e73370e ("clk: microchip: Add driver for Microchip PolarFire SoC")
Reviewed-by: Daire McNamara <daire.mcnamara@microchip.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220411072340.740981-1-conor.dooley@microchip.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

show more ...

clk: microchip: Add driver for Microchip PolarFire SoC

Add support for clock configuration on Microchip PolarFire SoC

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterh

clk: microchip: Add driver for Microchip PolarFire SoC

Add support for clock configuration on Microchip PolarFire SoC

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Co-developed-by: Padmarao Begari <padmarao.begari@microchip.com>
Signed-off-by: Padmarao Begari <padmarao.begari@microchip.com>
Signed-off-by: Daire McNamara <daire.mcnamara@microchip.com>
Co-developed-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220222121143.3316880-2-conor.dooley@microchip.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

show more ...