Original architecture clock code from where this driver was derived did not
include nothing related to mmc clocks. OpenWRT people started to use mtk-sd
upstream driver recently and they were forced to use a dts 'fixed-clock'
node with 48 MHz clock:
- https://github.com/openwrt/openwrt/pull/15896
The proper thing to do to avoid that is to add the mmc related clocks to the
driver to avoid a dts with fixed clocks nodes. The minimal documentation in
the mt7620 programming guide says that there is a BBP_PLL clock of 480 MHz
derived from the 40 MHz XTAL and from there a clock divider by ten produces
the desired SDHC clock of 48 MHz for the mmc. Hence add a fixed clock 'bbppll'
and factor clock 'sdhc' ten divider child to properly set the 'mmc' peripheral
clock with the desired 48 Mhz rate.
Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Link: https://lore.kernel.org/r/20240910044024.120009-4-sergio.paracuellos@gmail.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Base clocks are the first in being probed and are real dependencies of the
rest of fixed, factor and peripheral clocks. For old ralink SoCs RT2880,
RT305x and RT3883 'xtal' must be defined first since in any other case,
when fixed clocks are probed they are delayed until 'xtal' is probed so the
following warning appears:
WARNING: CPU: 0 PID: 0 at drivers/clk/ralink/clk-mtmips.c:499 rt3883_bus_recalc_rate+0x98/0x138
Modules linked in:
CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.43 #0
Stack : 805e58d0 00000000 00000004 8004f950 00000000 00000004 00000000 00000000
80669c54 80830000 80700000 805ae570 80670068 00000001 80669bf8 00000000
00000000 00000000 805ae570 80669b38 00000020 804db7dc 00000000 00000000
203a6d6d 80669b78 80669e48 70617773 00000000 805ae570 00000000 00000009
00000000 00000001 00000004 00000001 00000000 00000000 83fe43b0 00000000
...
Call Trace:
[<800065d0>] show_stack+0x64/0xf4
[<804bca14>] dump_stack_lvl+0x38/0x60
[<800218ac>] __warn+0x94/0xe4
[<8002195c>] warn_slowpath_fmt+0x60/0x94
[<80259ff8>] rt3883_bus_recalc_rate+0x98/0x138
[<80254530>] __clk_register+0x568/0x688
[<80254838>] of_clk_hw_register+0x18/0x2c
[<8070b910>] rt2880_clk_of_clk_init_driver+0x18c/0x594
[<8070b628>] of_clk_init+0x1c0/0x23c
[<806fc448>] plat_time_init+0x58/0x18c
[<806fdaf0>] time_init+0x10/0x6c
[<806f9bc4>] start_kernel+0x458/0x67c
---[ end trace 0000000000000000 ]---
When this driver was mainlined we could not find any active users of old
ralink SoCs so we cannot perform any real tests for them. Now, one user
of a Belkin f9k1109 version 1 device which uses RT3883 SoC appeared and
reported some issues in openWRT:
- https://github.com/openwrt/openwrt/issues/16054
Thus, define a 'rt2880_xtal_recalc_rate()' just returning the expected
frequency 40Mhz and use it along the old ralink SoCs to have a correct
boot trace with no warnings and a working clock plan from the beggining.
Fixes: 6f3b15586e ("clk: ralink: add clock and reset driver for MTMIPS SoCs")
Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Link: https://lore.kernel.org/r/20240910044024.120009-3-sergio.paracuellos@gmail.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Clock plan for Ralink SoC RT3883 needs an extra 'periph' clock to properly
set some peripherals that has this clock as their parent. When this driver
was mainlined we could not find any active users of this SoC so we cannot
perform any real tests for it. Now, one user of a Belkin f9k1109 version 1
device which uses this SoC appear and reported some issues in openWRT:
- https://github.com/openwrt/openwrt/issues/16054
The peripherals that are wrong are 'uart', 'i2c', 'i2s' and 'uartlite' which
has a not defined 'periph' clock as parent. Hence, introduce it to have a
properly working clock plan for this SoC.
Fixes: 6f3b15586e ("clk: ralink: add clock and reset driver for MTMIPS SoCs")
Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Link: https://lore.kernel.org/r/20240910044024.120009-2-sergio.paracuellos@gmail.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
When CONFIG_OF is disabled then the matching table is not referenced and
the following warning appears:
drivers/clk/ralink/clk-mtmips.c:821:34: warning: unused variable 'mtmips_of_match' [-Wunused-const-variable]
821 | static const struct of_device_id mtmips_of_match[] = {
| ^
There are two match tables in the driver: one for the clock driver and the
other for the reset driver. The only difference between them is that the
clock driver uses 'data' and does not have 'ralink,rt2880-reset' compatible.
Both just can be merged into a single one just by adding the compatible
'ralink,rt2880-reset' entry to 'mtmips_of_match[]', which will allow it to
be used for 'mtmips_clk_driver' (which doesn't use the data) as well as for
'mtmips_clk_init()' (which doesn't need get called for 'ralink,rt2880-reset').
Doing in this way ensures that 'CONFIG_OF' is not disabled anymore so the
above warning disapears.
Fixes: 6f3b15586e ("clk: ralink: add clock and reset driver for MTMIPS SoCs")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202307242310.CdOnd2py-lkp@intel.com/
Suggested-by: Arnd Bergmann <arnd@kernel.org>
Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Link: https://lore.kernel.org/r/20230827023932.501102-1-sergio.paracuellos@gmail.com
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
As found with Coccinelle[1], add __counted_by for struct clk_hw_onecell_data.
Additionally, since the element count member must be set before accessing
the annotated flexible array member, move its initialization earlier.
[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: Joel Stanley <joel@jms.id.au>
Cc: Andrew Jeffery <andrew@aj.id.au>
Cc: Taichi Sugaya <sugaya.taichi@socionext.com>
Cc: Takao Orito <orito.takao@socionext.com>
Cc: Qin Jian <qinjian@cqplus1.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Gregory Clement <gregory.clement@bootlin.com>
Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Cc: Andy Gross <agross@kernel.org>
Cc: Bjorn Andersson <andersson@kernel.org>
Cc: Konrad Dybcio <konrad.dybcio@linaro.org>
Cc: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: Jernej Skrabec <jernej.skrabec@gmail.com>
Cc: David Airlie <airlied@gmail.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Samuel Holland <samuel@sholland.org>
Cc: Vinod Koul <vkoul@kernel.org>
Cc: Kishon Vijay Abraham I <kishon@kernel.org>
Cc: linux-clk@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-aspeed@lists.ozlabs.org
Cc: linux-arm-msm@vger.kernel.org
Cc: linux-mediatek@lists.infradead.org
Cc: dri-devel@lists.freedesktop.org
Cc: linux-sunxi@lists.linux.dev
Cc: linux-phy@lists.infradead.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230817203019.never.795-kees@kernel.org
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Clang warns:
drivers/clk/ralink/clk-mtmips.c:309:9: error: variable 'ret' is uninitialized when used here [-Werror,-Wuninitialized]
309 | return ret;
| ^~~
drivers/clk/ralink/clk-mtmips.c:285:9: note: initialize the variable 'ret' to silence this warning
285 | int ret, i;
| ^
| = 0
drivers/clk/ralink/clk-mtmips.c:359:9: error: variable 'ret' is uninitialized when used here [-Werror,-Wuninitialized]
359 | return ret;
| ^~~
drivers/clk/ralink/clk-mtmips.c:335:9: note: initialize the variable 'ret' to silence this warning
335 | int ret, i;
| ^
| = 0
2 errors generated.
Set ret to the return value of clk_hw_register_fixed_rate() using the
PTR_ERR() macro, which ensures ret is not used uninitialized, clearing
up the warning.
Fixes: 6f3b15586e ("clk: ralink: add clock and reset driver for MTMIPS SoCs")
Closes: https://github.com/ClangBuiltLinux/linux/issues/1879
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Until now, clock related code for old ralink SoCs was based in fixed clocks
using 'clk_register_fixed_rate' and 'clkdev_create' directly doing in code
and not using device tree at all for their definition. Including this driver
is an effort to be able to define proper clocks using device tree and also
cleaning all the clock and reset related code from 'arch/mips/ralink' dir.
This clock and reset driver covers all the ralink SoCs but MT7621 which is
the newest and provides gating and some differences that make it different
from its predecesors. It has its own driver since some time ago. The ralink
SoCs we are taking about are RT2880, RT3050, RT3052, RT3350, RT3352, RT3883,
RT5350, MT7620, MT7628 and MT7688. Mostly the code in this new driver has
been extracted from 'arch/mips/ralink' and cleanly put using kernel clock
driver APIs. The clock plans for this SoCs only talks about relation between
CPU frequency and BUS frequency. This relation is different depending on the
particular SoC. CPU clock is derived from XTAL frequencies.
Depending on the SoC we have the following frequencies:
* RT2880 SoC:
- XTAL: 40 MHz.
- CPU: 250, 266, 280 or 300 MHz.
- BUS: CPU / 2 MHz.
* RT3050, RT3052, RT3350:
- XTAL: 40 MHz.
- CPU: 320 or 384 MHz.
- BUS: CPU / 3 MHz.
* RT3352:
- XTAL: 40 MHz.
- CPU: 384 or 400 MHz.
- BUS: CPU / 3 MHz.
- PERIPH: 40 MHz.
* RT3383:
- XTAL: 40 MHz.
- CPU: 250, 384, 480 or 500 MHz.
- BUS: Depends on RAM Type and CPU:
+ RAM DDR2: 125. ELSE 83 MHz.
+ RAM DDR2: 128. ELSE 96 MHz.
+ RAM DDR2: 160. ELSE 120 MHz.
+ RAM DDR2: 166. ELSE 125 MHz.
* RT5350:
- XTAL: 40 MHz.
- CPU: 300, 320 or 360 MHz.
- BUS: CPU / 3, CPU / 4, CPU / 3 MHz.
- PERIPH: 40 MHz.
* MT7628 and MT7688:
- XTAL: 20 MHz or 40 MHz.
- CPU: 575 or 580 MHz.
- BUS: CPU / 3.
- PCMI2S: 480 MHz.
- PERIPH: 40 MHz.
* MT7620:
- XTAL: 20 MHz or 40 MHz.
- PLL: XTAL, 480, 600 MHz.
- CPU: depends on PLL and some mult and dividers.
- BUS: depends on PLL and some mult and dividers.
- PERIPH: 40 or XTAL MHz.
MT7620 is a bit more complex deriving CPU clock from a PLL and an bunch of
register reads and predividers. To derive CPU and BUS frequencies in the
MT7620 SoC 'mt7620_calc_rate()' helper is used.
In the case XTAL can have different frequencies and we need a different
clock frequency for peripherals 'periph' clock in introduced.
The rest of the peripherals present in the SoC just follow their parent
frequencies.
With this information the clk driver will provide all the clock and reset
functionality from a set of hardcoded clocks allowing to define a nice
device tree without fixed clocks.
Acked-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Compiling clock driver with CONFIG_UBSAN enabled shows the following trace:
UBSAN: shift-out-of-bounds in drivers/clk/ralink/clk-mt7621.c:121:15
shift exponent 131072 is too large for 32-bit type 'long unsigned int'
CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.15.86 #0
Stack : ...
Call Trace:
[<80009a58>] show_stack+0x38/0x118
[<8045ce04>] dump_stack_lvl+0x60/0x80
[<80458868>] ubsan_epilogue+0x10/0x54
[<804590e0>] __ubsan_handle_shift_out_of_bounds+0x118/0x190
[<804c9a10>] mt7621_gate_is_enabled+0x98/0xa0
[<804bb774>] clk_core_is_enabled+0x34/0x90
[<80aad73c>] clk_disable_unused_subtree+0x98/0x1e4
[<80aad6d4>] clk_disable_unused_subtree+0x30/0x1e4
[<80aad6d4>] clk_disable_unused_subtree+0x30/0x1e4
[<80aad900>] clk_disable_unused+0x78/0x120
[<80002030>] do_one_initcall+0x54/0x1f0
[<80a922a4>] kernel_init_freeable+0x280/0x31c
[<808047c4>] kernel_init+0x20/0x118
[<80003e58>] ret_from_kernel_thread+0x14/0x1c
Shifting a value (131032) larger than the type (32 bit unsigned integer)
is undefined behaviour in C.
The problem is in 'mt7621_gate_is_enabled()' function which is using the
'BIT()' kernel macro with the bit index for the clock gate to check if the
bit is set. When the clock gates structure is created driver is already
setting 'bit_idx' using 'BIT()' macro, so we are wrongly applying an extra
'BIT()' mask here. Removing it solve the problem and makes this function
correct. However when clock gating is correctly working, the kernel starts
disabling those clocks that are not requested. Some drivers for this SoC
are older than this clock driver itself. So to avoid the kernel to disable
clocks that have been enabled until now, we must apply 'CLK_IS_CRITICAL'
flag on gates initialization code.
Fixes: 48df7a26f4 ("clk: ralink: add clock driver for mt7621 SoC")
Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Link: https://lore.kernel.org/r/20230206083305.147582-1-sergio.paracuellos@gmail.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
MT7621 system controller node is already providing the clocks for the whole
system but must also serve as a reset provider. Hence, add reset controller
related code to the clock driver itself. To get resets properly ready for
the rest of the world we need to move platform driver initialization process
to 'arch_initcall'.
CC: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Link: https://lore.kernel.org/r/20220210094859.927868-3-sergio.paracuellos@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
'clk_init_data' for gates is setting up 'CLK_IS_CRITICAL'
flag for all of them. This was being doing because some
drivers of this SoC might not be ready to use the clock
and we don't wanted the kernel to disable them since default
behaviour without clock driver was to set all gate bits to
enabled state. After a bit more testing and checking driver
code it is safe to remove this flag and just let the kernel
to disable those gates that are not in use. No regressions
seems to appear.
Fixes: 48df7a26f4 ("clk: ralink: add clock driver for mt7621 SoC")
Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Link: https://lore.kernel.org/r/20210727055537.11785-1-sergio.paracuellos@gmail.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
The documentation for this SOC only talks about two
registers regarding to the clocks:
* SYSC_REG_CPLL_CLKCFG0 - provides some information about
boostrapped refclock. PLL and dividers used for CPU and some
sort of BUS.
* SYSC_REG_CPLL_CLKCFG1 - a banch of gates to enable/disable
clocks for all or some ip cores.
Looking into driver code, and some openWRT patched there are
another frequencies which are used in some drivers (uart, sd...).
According to all of this information the clock plan for this
SoC is set as follows:
- Main top clock "xtal" from where all the rest of the world is
derived.
- CPU clock "cpu" derived from "xtal" frequencies and a bunch of
register reads and predividers.
- BUS clock "bus" derived from "cpu" and with (cpu / 4) MHz.
- Fixed clocks from "xtal":
* "50m": 50 MHz.
* "125m": 125 MHz.
* "150m": 150 MHz.
* "250m": 250 MHz.
* "270m": 270 MHz.
We also have a buch of gate clocks with their parents:
* "hsdma": "150m"
* "fe": "250m"
* "sp_divtx": "270m"
* "timer": "50m"
* "pcm": "270m"
* "pio": "50m"
* "gdma": "bus"
* "nand": "125m"
* "i2c": "50m"
* "i2s": "270m"
* "spi": "bus"
* "uart1": "50m"
* "uart2": "50m"
* "uart3": "50m"
* "eth": "50m"
* "pcie0": "125m"
* "pcie1": "125m"
* "pcie2": "125m"
* "crypto": "250m"
* "shxc": "50m"
With this information the clk driver will provide clock and gates
functionality from a a set of hardcoded clocks allowing to define
a nice device tree without fixed clocks.
Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Link: https://lore.kernel.org/r/20210410055059.13518-2-sergio.paracuellos@gmail.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
