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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
| commit | 4352b8aee98005853aa63f57d6377282de17a33f (patch) | |
| tree | 27614d7a9ef05c32d089004e104364ce42324837 /arch/powerpc/lib/div64.S | |
| download | linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip | |
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni:
"A new driver this cycle, for the AMD AXI I3C controller.
There are also new features such as IBI wakeup support, SETAASA device
discovery and ACPI support for the the DAA methods, meaning we can now
communicate with the SPD devices on DDR5 modules.
New driver:
- AMD AXI I3C master controller
Subsystem:
- I3C Common Command Code (CCC) handling improvements, especially
around GET CCCs
- SETAASA device discovery support
- ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
well as I2C devices on I3C bus
- IBI-based wakeup support
Drivers:
- dw: SETAASA support
- mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
controller support, PIO queue management support for HCI v1.2
- renesas: improve suspend to RAM support, add runtime PM support"
* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
i3c: dw: reduce do_daa time if there's no client
i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
i3c: dw: rename "pclk" to "apb" to match dt-binding
i3c: dw: make struct dw_i3c_cmd smaller
i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
i3c: renesas: Don't register devices when ENTDAA times out
i3c: master: dw-i3c-master: fix OD timing for first broadcast
i3c: mipi-i3c-hci: Advertise IBI wakeup capability
i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
i3c: master: Reject IBI requests from non-IBI-capable devices
i3c: master: Add helper to query bus wakeup requirements
i3c: master: Report wakeup events for IBIs
i3c: master: Support IBI-based wakeup capability
i3c: master: Fix potential UAF in i3c_device_match()
i3c: master: Fix potential UAF in i3c_device_uevent()
i3c: Make dev->desc locking assumptions explicit
i3c: master: Fix use-after-free of master->this
...
Diffstat (limited to 'arch/powerpc/lib/div64.S')
| -rw-r--r-- | arch/powerpc/lib/div64.S | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/arch/powerpc/lib/div64.S b/arch/powerpc/lib/div64.S new file mode 100644 index 000000000..3d5426e7d --- /dev/null +++ b/arch/powerpc/lib/div64.S @@ -0,0 +1,55 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Divide a 64-bit unsigned number by a 32-bit unsigned number. + * This routine assumes that the top 32 bits of the dividend are + * non-zero to start with. + * On entry, r3 points to the dividend, which get overwritten with + * the 64-bit quotient, and r4 contains the divisor. + * On exit, r3 contains the remainder. + * + * Copyright (C) 2002 Paul Mackerras, IBM Corp. + */ +#include <asm/ppc_asm.h> +#include <asm/processor.h> + +_GLOBAL(__div64_32) + lwz r5,0(r3) # get the dividend into r5/r6 + lwz r6,4(r3) + cmplw r5,r4 + li r7,0 + li r8,0 + blt 1f + divwu r7,r5,r4 # if dividend.hi >= divisor, + mullw r0,r7,r4 # quotient.hi = dividend.hi / divisor + subf. r5,r0,r5 # dividend.hi %= divisor + beq 3f +1: mr r11,r5 # here dividend.hi != 0 + andis. r0,r5,0xc000 + bne 2f + cntlzw r0,r5 # we are shifting the dividend right + li r10,-1 # to make it < 2^32, and shifting + srw r10,r10,r0 # the divisor right the same amount, + addc r9,r4,r10 # rounding up (so the estimate cannot + andc r11,r6,r10 # ever be too large, only too small) + andc r9,r9,r10 + addze r9,r9 + or r11,r5,r11 + rotlw r9,r9,r0 + rotlw r11,r11,r0 + divwu r11,r11,r9 # then we divide the shifted quantities +2: mullw r10,r11,r4 # to get an estimate of the quotient, + mulhwu r9,r11,r4 # multiply the estimate by the divisor, + subfc r6,r10,r6 # take the product from the divisor, + add r8,r8,r11 # and add the estimate to the accumulated + subfe. r5,r9,r5 # quotient + bne 1b +3: cmplw r6,r4 + blt 4f + divwu r0,r6,r4 # perform the remaining 32-bit division + mullw r10,r0,r4 # and get the remainder + add r8,r8,r0 + subf r6,r10,r6 +4: stw r7,0(r3) # return the quotient in *r3 + stw r8,4(r3) + mr r3,r6 # return the remainder in r3 + blr |
