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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-24 08:46:03 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-24 08:46:03 -0700 |
| commit | cf9610f9116d55c5a66ef9f1faecacabd93a9322 (patch) | |
| tree | 757a3d280760c654767631cab5ad8af2d86d1848 /lib/math/reciprocal_div.c | |
| download | linux-stable-cf9610f9116d55c5a66ef9f1faecacabd93a9322.tar.gz linux-stable-cf9610f9116d55c5a66ef9f1faecacabd93a9322.zip | |
Merge tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrlgrafted
Pull pin control updates from Linus Walleij:
"Core changes:
- Use the non-blocking mux_state_try_select() in the generic MUX pin
control back-end
- Free pin maps on pinctrl_generic_to_map() failure in the core
helpers
New hardware pin control:
- Qualcomm Maili TLMM SoC, PMG1110 PMIC, and Eliza LPASS LPI TLMM SoC
(this is for the low power audio, LPASS = Low Power Audio SubSystem
portions)
- Upboard support on top of the Intel pin controller
- Apple T6030 and T6031 support (just compatible strings)
- Samsung Exynos 8855 SoC
- Mediatek MT6858 SoC
- Rockchip RK3308B and RV1106 SoCs
- Airoha EN7523 and AN7563 SoCs
Improvements:
- Qualcomm TLMM GPIOs are unconditionally marked as wakeup capable
- Qualcomm improvements on top of the Qualcomm PDC (power domain
controller) irqchip improvements from tglx:s tree
- Qualcomm IPQ806x and IPQ9650 non-urgent pin grop fixups
- The NPCM8xx driver has been put into shape fixing many pin and
group definitions
- Some non-urgent Tegra 264 pin assignments are fixed up
- Some non-urgent fixups to Airoha AN7581 and AN7583 registers and
pin assignments, missing features etc"
* tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (130 commits)
dt-bindings: pinctrl: Convert TI DA850 pupd to DT schema
pinctrl: meson: sync some modify from A4
pinctrl: meson: a4: Add input enable pin configuration
pinctrl: realtek: rtd1625: remove unused group name spdif_sel
pinctrl: realtek: rtd1625: fix base_bit for VE4 GPIO 13
dt-bindings: pinctrl: microchip,pic32mzda-pinctrl: Convert to DT schema
Revert "Merge branch 'ib-rsk7204' into devel"
pinctrl: rockchip: Add RV1106 pinctrl support
dt-bindings: pinctrl: rockchip: Add RV1106 compatible
pinctrl: rockchip: Decode drive strength in the get function
pinctrl: fix PINCTRL_GENERIC_MUX not always being selectable
pinctrl: airoha: add support of an7563 SoC
dt-bindings: pinctrl: airoha: add support of an7563 pin controller
pinctrl: airoha: try to find chip scu node by phandle first
pinctrl: airoha: add support of en7523 SoC
dt-bindings: pinctrl: airoha: add support of en7523 pin controller
pinctrl: airoha: an7583: add support for olt pinmux
pinctrl: airoha: an7583: add support for pon_alt pinmux
pinctrl: airoha: an7583: add support for npu_uart pinmux
dt-bindings: pinctrl: airoha: an7583: add missed features
...
Diffstat (limited to 'lib/math/reciprocal_div.c')
| -rw-r--r-- | lib/math/reciprocal_div.c | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/lib/math/reciprocal_div.c b/lib/math/reciprocal_div.c new file mode 100644 index 000000000..6cb4adbb8 --- /dev/null +++ b/lib/math/reciprocal_div.c @@ -0,0 +1,73 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/bitops.h> +#include <linux/bug.h> +#include <linux/export.h> +#include <linux/limits.h> +#include <linux/math.h> +#include <linux/minmax.h> +#include <linux/types.h> + +#include <linux/reciprocal_div.h> + +/* + * For a description of the algorithm please have a look at + * include/linux/reciprocal_div.h + */ + +struct reciprocal_value reciprocal_value(u32 d) +{ + struct reciprocal_value R; + u64 m; + int l; + + l = fls(d - 1); + m = ((1ULL << 32) * ((1ULL << l) - d)); + do_div(m, d); + ++m; + R.m = (u32)m; + R.sh1 = min(l, 1); + R.sh2 = max(l - 1, 0); + + return R; +} +EXPORT_SYMBOL(reciprocal_value); + +struct reciprocal_value_adv reciprocal_value_adv(u32 d, u8 prec) +{ + struct reciprocal_value_adv R; + u32 l, post_shift; + u64 mhigh, mlow; + + /* ceil(log2(d)) */ + l = fls(d - 1); + /* NOTE: mlow/mhigh could overflow u64 when l == 32. This case needs to + * be handled before calling "reciprocal_value_adv", please see the + * comment at include/linux/reciprocal_div.h. + */ + WARN(l == 32, + "ceil(log2(0x%08x)) == 32, %s doesn't support such divisor", + d, __func__); + post_shift = l; + mlow = 1ULL << (32 + l); + do_div(mlow, d); + mhigh = (1ULL << (32 + l)) + (1ULL << (32 + l - prec)); + do_div(mhigh, d); + + for (; post_shift > 0; post_shift--) { + u64 lo = mlow >> 1, hi = mhigh >> 1; + + if (lo >= hi) + break; + + mlow = lo; + mhigh = hi; + } + + R.m = (u32)mhigh; + R.sh = post_shift; + R.exp = l; + R.is_wide_m = mhigh > U32_MAX; + + return R; +} +EXPORT_SYMBOL(reciprocal_value_adv); |
