The clock controller of Loongson-2K0300 consists of three PLLs, requires
an 120MHz external reference clock to function, and generates clocks in
various frequencies for SoC peripherals.
Clock definitions for previous SoC generations could be reused for most
clock hardwares. There're two gates marked as critical, clk_node_gate
and clk_boot_gate, which supply the CPU cores and the system
configuration bus. Disabling them leads to a SoC hang.
Signed-off-by: Yao Zi <ziyao@disroot.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Loongson-2K0300 requires a reference clock with a frequency different
from previous SoCs (120MHz v.s. 100MHz), thus hardcoding the firmware
name of the reference clock as ref_100m isn't a good idea.
This patch retrives the clock name of the reference clock dynamically
during probe, avoiding the hardcoded pdata structure and preparing for
support of future SoCs.
Signed-off-by: Yao Zi <ziyao@disroot.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
LS2K0300 and LS2K0500 ship divider clocks which allows zero divisors,
in which case the divider acts the same as one is specified.
Let's pass CLK_DIVIDER_ALLOW_ZERO when registering divider clocks to
prepare for future introduction of these clocks.
Signed-off-by: Yao Zi <ziyao@disroot.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
LS2K0300 and LS2K1500 ship scale clocks with an alternative mode.
There's one mode bit in clock configuration register indicating the
operation mode.
When mode bit is unset, the scale clock acts the same as previous
generation of scale clocks. When it's set, a different equation for
calculating result frequency, Fout = Fin / (scale + 1), is used.
This patch adds frequency calculation support for the scale clock
variant. A helper macro, CLK_SCALE_MODE, is added to simplify
definitions.
Signed-off-by: Yao Zi <ziyao@disroot.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Some gate clocks need to be supplied with flags, e.g., it may be
required to specify CLK_IS_CRTICAL for CPU clocks.
Add a field to loongson2_clk_board_info for representing clock flags,
and specify it when registering gate clocks. A new helper macro,
CLK_GATE_FLAGS, is added to simplify definitions.
Signed-off-by: Yao Zi <ziyao@disroot.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
* clk-fixes:
clk: clk-loongson2: Fix the number count of clk provider
clk: mmp2: call pm_genpd_init() only after genpd.name is set
clk: sunxi-ng: a100: enable MMC clock reparenting
clk: clk-imx8mp-audiomix: fix function signature
clk: thead: Fix TH1520 emmc and shdci clock rate
Since commit 02fb4f0084 ("clk: clk-loongson2: Fix potential buffer
overflow in flexible-array member access"), the clk provider register is
failed.
The count of `clks_num` is shown below:
for (p = data; p->name; p++)
clks_num++;
In fact, `clks_num` represents the number of SoC clocks and should be
expressed as the maximum value of the clock binding id in use (p->id + 1).
Now we fix it to avoid the following error when trying to register a clk
provider:
[ 13.409595] of_clk_hw_onecell_get: invalid index 17
Cc: stable@vger.kernel.org
Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Fixes: 02fb4f0084 ("clk: clk-loongson2: Fix potential buffer overflow in flexible-array member access")
Signed-off-by: Binbin Zhou <zhoubinbin@loongson.cn>
Link: https://lore.kernel.org/r/82e43d89a9a6791129cf8ea14f4eeb666cd87be4.1736856470.git.zhoubinbin@loongson.cn
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Flexible-array member `hws` in `struct clk_hw_onecell_data` is annotated
with the `counted_by()` attribute. This means that when memory is
allocated for this array, the _counter_, which in this case is member
`num` in the flexible structure, should be set to the maximum number of
elements the flexible array can contain, or fewer.
In this case, the total number of elements for the flexible array is
determined by variable `clks_num` when allocating heap space via
`devm_kzalloc()`, as shown below:
289 struct loongson2_clk_provider *clp;
...
296 for (p = data; p->name; p++)
297 clks_num++;
298
299 clp = devm_kzalloc(dev, struct_size(clp, clk_data.hws, clks_num),
300 GFP_KERNEL);
So, `clp->clk_data.num` should be set to `clks_num` or less, and not
exceed `clks_num`, as is currently the case. Otherwise, if data is
written into `clp->clk_data.hws[clks_num]`, the instrumentation
provided by the compiler won't detect the overflow, leading to a
memory corruption bug at runtime.
Fix this issue by setting `clp->clk_data.num` to `clks_num`.
Fixes: 9796ec0bd0 ("clk: clk-loongson2: Refactor driver for adding new platforms")
Cc: stable@vger.kernel.org
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/ZzaN5MpmMr0hwHw9@kspp
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Some heap space is allocated for the flexible structure `struct
clk_hw_onecell_data` and its flexible-array member `hws` through
the composite structure `struct loongson2_clk_provider` in function
`loongson2_clk_probe()`, as shown below:
289 struct loongson2_clk_provider *clp;
...
296 for (p = data; p->name; p++)
297 clks_num++;
298
299 clp = devm_kzalloc(dev, struct_size(clp, clk_data.hws, clks_num),
300 GFP_KERNEL);
Then some data is written into the flexible array:
350 clp->clk_data.hws[p->id] = hw;
This corrupts `clk_lock`, which is the spinlock variable immediately
following the `clk_data` member in `struct loongson2_clk_provider`:
struct loongson2_clk_provider {
void __iomem *base;
struct device *dev;
struct clk_hw_onecell_data clk_data;
spinlock_t clk_lock; /* protect access to DIV registers */
};
The problem is that the flexible structure is currently placed in the
middle of `struct loongson2_clk_provider` instead of at the end.
Fix this by moving `struct clk_hw_onecell_data clk_data;` to the end of
`struct loongson2_clk_provider`. Also, add a code comment to help
prevent this from happening again in case new members are added to the
structure in the future.
This change also fixes the following -Wflex-array-member-not-at-end
warning:
drivers/clk/clk-loongson2.c:32:36: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end]
Fixes: 9796ec0bd0 ("clk: clk-loongson2: Refactor driver for adding new platforms")
Cc: stable@vger.kernel.org
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/ZzZ-cd_EFXs6qFaH@kspp
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
The driver only supported loongson-2K1000 at first, but the clock
structure of loongson-2K0500 and loongson-2K2000 are actually similar,
and I tried to refactor the whole driver to adjust to the addition of
the new platform.
Briefly, I have divided all clocks into three categories according to
their properties and their parent clocks: Independent PLLs, clocks based
on frequency scales, and clock dividers.
Signed-off-by: Binbin Zhou <zhoubinbin@loongson.cn>
Link: https://lore.kernel.org/r/fb020d1ca19e6f4cdcc95c87b2748869ca76b8ec.1712731524.git.zhoubinbin@loongson.cn
Acked-by: Huacai Chen <chenhuacai@loongson.cn>
[sboyd@kernel.org: Drop clk.h include]
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
This driver provides support for clock controller on Loongson-2 SoC,
the Loongson-2 SoC uses a 100MHz clock as the PLL reference clock,
there are five independent PLLs inside, each of which PLL can
provide up to three sets of frequency dependent clock outputs.
Signed-off-by: Yinbo Zhu <zhuyinbo@loongson.cn>
Link: https://lore.kernel.org/r/20230323025229.2971-2-zhuyinbo@loongson.cn
Signed-off-by: Stephen Boyd <sboyd@kernel.org>