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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
commitcf9610f9116d55c5a66ef9f1faecacabd93a9322 (patch)
tree757a3d280760c654767631cab5ad8af2d86d1848 /arch/alpha/lib/divide.S
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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 ...
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+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * arch/alpha/lib/divide.S
+ *
+ * (C) 1995 Linus Torvalds
+ *
+ * Alpha division..
+ */
+
+/*
+ * The alpha chip doesn't provide hardware division, so we have to do it
+ * by hand. The compiler expects the functions
+ *
+ * __divqu: 64-bit unsigned long divide
+ * __remqu: 64-bit unsigned long remainder
+ * __divqs/__remqs: signed 64-bit
+ * __divlu/__remlu: unsigned 32-bit
+ * __divls/__remls: signed 32-bit
+ *
+ * These are not normal C functions: instead of the normal
+ * calling sequence, these expect their arguments in registers
+ * $24 and $25, and return the result in $27. Register $28 may
+ * be clobbered (assembly temporary), anything else must be saved.
+ *
+ * In short: painful.
+ *
+ * This is a rather simple bit-at-a-time algorithm: it's very good
+ * at dividing random 64-bit numbers, but the more usual case where
+ * the divisor is small is handled better by the DEC algorithm
+ * using lookup tables. This uses much less memory, though, and is
+ * nicer on the cache.. Besides, I don't know the copyright status
+ * of the DEC code.
+ */
+
+/*
+ * My temporaries:
+ * $0 - current bit
+ * $1 - shifted divisor
+ * $2 - modulus/quotient
+ *
+ * $23 - return address
+ * $24 - dividend
+ * $25 - divisor
+ *
+ * $27 - quotient/modulus
+ * $28 - compare status
+ */
+
+#include <linux/export.h>
+#define halt .long 0
+
+/*
+ * Select function type and registers
+ */
+#define mask $0
+#define divisor $1
+#define compare $28
+#define tmp1 $3
+#define tmp2 $4
+
+#ifdef DIV
+#define DIV_ONLY(x,y...) x,##y
+#define MOD_ONLY(x,y...)
+#define func(x) __div##x
+#define modulus $2
+#define quotient $27
+#define GETSIGN(x) xor $24,$25,x
+#define STACK 48
+#else
+#define DIV_ONLY(x,y...)
+#define MOD_ONLY(x,y...) x,##y
+#define func(x) __rem##x
+#define modulus $27
+#define quotient $2
+#define GETSIGN(x) bis $24,$24,x
+#define STACK 32
+#endif
+
+/*
+ * For 32-bit operations, we need to extend to 64-bit
+ */
+#ifdef INTSIZE
+#define ufunction func(lu)
+#define sfunction func(l)
+#define LONGIFY(x) zapnot x,15,x
+#define SLONGIFY(x) addl x,0,x
+#else
+#define ufunction func(qu)
+#define sfunction func(q)
+#define LONGIFY(x)
+#define SLONGIFY(x)
+#endif
+
+.set noat
+.align 3
+.globl ufunction
+.ent ufunction
+ufunction:
+ subq $30,STACK,$30
+ .frame $30,STACK,$23
+ .prologue 0
+
+7: stq $1, 0($30)
+ bis $25,$25,divisor
+ stq $2, 8($30)
+ bis $24,$24,modulus
+ stq $0,16($30)
+ bis $31,$31,quotient
+ LONGIFY(divisor)
+ stq tmp1,24($30)
+ LONGIFY(modulus)
+ bis $31,1,mask
+ DIV_ONLY(stq tmp2,32($30))
+ beq divisor, 9f /* div by zero */
+
+#ifdef INTSIZE
+ /*
+ * shift divisor left, using 3-bit shifts for
+ * 32-bit divides as we can't overflow. Three-bit
+ * shifts will result in looping three times less
+ * here, but can result in two loops more later.
+ * Thus using a large shift isn't worth it (and
+ * s8add pairs better than a sll..)
+ */
+1: cmpult divisor,modulus,compare
+ s8addq divisor,$31,divisor
+ s8addq mask,$31,mask
+ bne compare,1b
+#else
+1: cmpult divisor,modulus,compare
+ blt divisor, 2f
+ addq divisor,divisor,divisor
+ addq mask,mask,mask
+ bne compare,1b
+ unop
+#endif
+
+ /* ok, start to go right again.. */
+2: DIV_ONLY(addq quotient,mask,tmp2)
+ srl mask,1,mask
+ cmpule divisor,modulus,compare
+ subq modulus,divisor,tmp1
+ DIV_ONLY(cmovne compare,tmp2,quotient)
+ srl divisor,1,divisor
+ cmovne compare,tmp1,modulus
+ bne mask,2b
+
+9: ldq $1, 0($30)
+ ldq $2, 8($30)
+ ldq $0,16($30)
+ ldq tmp1,24($30)
+ DIV_ONLY(ldq tmp2,32($30))
+ addq $30,STACK,$30
+ ret $31,($23),1
+ .end ufunction
+EXPORT_SYMBOL(ufunction)
+
+/*
+ * Uhh.. Ugly signed division. I'd rather not have it at all, but
+ * it's needed in some circumstances. There are different ways to
+ * handle this, really. This does:
+ * -a / b = a / -b = -(a / b)
+ * -a % b = -(a % b)
+ * a % -b = a % b
+ * which is probably not the best solution, but at least should
+ * have the property that (x/y)*y + (x%y) = x.
+ */
+.align 3
+.globl sfunction
+.ent sfunction
+sfunction:
+ subq $30,STACK,$30
+ .frame $30,STACK,$23
+ .prologue 0
+ bis $24,$25,$28
+ SLONGIFY($28)
+ bge $28,7b
+ stq $24,0($30)
+ subq $31,$24,$28
+ stq $25,8($30)
+ cmovlt $24,$28,$24 /* abs($24) */
+ stq $23,16($30)
+ subq $31,$25,$28
+ stq tmp1,24($30)
+ cmovlt $25,$28,$25 /* abs($25) */
+ unop
+ bsr $23,ufunction
+ ldq $24,0($30)
+ ldq $25,8($30)
+ GETSIGN($28)
+ subq $31,$27,tmp1
+ SLONGIFY($28)
+ ldq $23,16($30)
+ cmovlt $28,tmp1,$27
+ ldq tmp1,24($30)
+ addq $30,STACK,$30
+ ret $31,($23),1
+ .end sfunction
+EXPORT_SYMBOL(sfunction)