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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /arch/alpha/lib/checksum.c
downloadlinux-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/alpha/lib/checksum.c')
-rw-r--r--arch/alpha/lib/checksum.c186
1 files changed, 186 insertions, 0 deletions
diff --git a/arch/alpha/lib/checksum.c b/arch/alpha/lib/checksum.c
new file mode 100644
index 000000000..27b2a9edf
--- /dev/null
+++ b/arch/alpha/lib/checksum.c
@@ -0,0 +1,186 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * arch/alpha/lib/checksum.c
+ *
+ * This file contains network checksum routines that are better done
+ * in an architecture-specific manner due to speed..
+ * Comments in other versions indicate that the algorithms are from RFC1071
+ *
+ * accelerated versions (and 21264 assembly versions ) contributed by
+ * Rick Gorton <rick.gorton@alpha-processor.com>
+ */
+
+#include <linux/module.h>
+#include <linux/string.h>
+#include <net/checksum.h>
+
+#include <asm/byteorder.h>
+#include <asm/checksum.h>
+
+static inline unsigned short from64to16(unsigned long x)
+{
+ /* Using extract instructions is a bit more efficient
+ than the original shift/bitmask version. */
+
+ union {
+ unsigned long ul;
+ unsigned int ui[2];
+ unsigned short us[4];
+ } in_v, tmp_v, out_v;
+
+ in_v.ul = x;
+ tmp_v.ul = (unsigned long) in_v.ui[0] + (unsigned long) in_v.ui[1];
+
+ /* Since the bits of tmp_v.sh[3] are going to always be zero,
+ we don't have to bother to add that in. */
+ out_v.ul = (unsigned long) tmp_v.us[0] + (unsigned long) tmp_v.us[1]
+ + (unsigned long) tmp_v.us[2];
+
+ /* Similarly, out_v.us[2] is always zero for the final add. */
+ return out_v.us[0] + out_v.us[1];
+}
+
+/*
+ * computes the checksum of the TCP/UDP pseudo-header
+ * returns a 16-bit checksum, already complemented.
+ */
+__sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
+ __u32 len, __u8 proto, __wsum sum)
+{
+ return (__force __sum16)~from64to16(
+ (__force u64)saddr + (__force u64)daddr +
+ (__force u64)sum + ((len + proto) << 8));
+}
+EXPORT_SYMBOL(csum_tcpudp_magic);
+
+__wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
+ __u32 len, __u8 proto, __wsum sum)
+{
+ unsigned long result;
+
+ result = (__force u64)saddr + (__force u64)daddr +
+ (__force u64)sum + ((len + proto) << 8);
+
+ /* Fold down to 32-bits so we don't lose in the typedef-less
+ network stack. */
+ /* 64 to 33 */
+ result = (result & 0xffffffff) + (result >> 32);
+ /* 33 to 32 */
+ result = (result & 0xffffffff) + (result >> 32);
+ return (__force __wsum)result;
+}
+EXPORT_SYMBOL(csum_tcpudp_nofold);
+
+/*
+ * Do a 64-bit checksum on an arbitrary memory area..
+ *
+ * This isn't a great routine, but it's not _horrible_ either. The
+ * inner loop could be unrolled a bit further, and there are better
+ * ways to do the carry, but this is reasonable.
+ */
+static inline unsigned long do_csum(const unsigned char * buff, int len)
+{
+ int odd, count;
+ unsigned long result = 0;
+
+ if (len <= 0)
+ goto out;
+ odd = 1 & (unsigned long) buff;
+ if (odd) {
+ result = *buff << 8;
+ len--;
+ buff++;
+ }
+ count = len >> 1; /* nr of 16-bit words.. */
+ if (count) {
+ if (2 & (unsigned long) buff) {
+ result += *(unsigned short *) buff;
+ count--;
+ len -= 2;
+ buff += 2;
+ }
+ count >>= 1; /* nr of 32-bit words.. */
+ if (count) {
+ if (4 & (unsigned long) buff) {
+ result += *(unsigned int *) buff;
+ count--;
+ len -= 4;
+ buff += 4;
+ }
+ count >>= 1; /* nr of 64-bit words.. */
+ if (count) {
+ unsigned long carry = 0;
+ do {
+ unsigned long w = *(unsigned long *) buff;
+ count--;
+ buff += 8;
+ result += carry;
+ result += w;
+ carry = (w > result);
+ } while (count);
+ result += carry;
+ result = (result & 0xffffffff) + (result >> 32);
+ }
+ if (len & 4) {
+ result += *(unsigned int *) buff;
+ buff += 4;
+ }
+ }
+ if (len & 2) {
+ result += *(unsigned short *) buff;
+ buff += 2;
+ }
+ }
+ if (len & 1)
+ result += *buff;
+ result = from64to16(result);
+ if (odd)
+ result = ((result >> 8) & 0xff) | ((result & 0xff) << 8);
+out:
+ return result;
+}
+
+/*
+ * This is a version of ip_compute_csum() optimized for IP headers,
+ * which always checksum on 4 octet boundaries.
+ */
+__sum16 ip_fast_csum(const void *iph, unsigned int ihl)
+{
+ return (__force __sum16)~do_csum(iph,ihl*4);
+}
+EXPORT_SYMBOL(ip_fast_csum);
+
+/*
+ * computes the checksum of a memory block at buff, length len,
+ * and adds in "sum" (32-bit)
+ *
+ * returns a 32-bit number suitable for feeding into itself
+ * or csum_tcpudp_magic
+ *
+ * this function must be called with even lengths, except
+ * for the last fragment, which may be odd
+ *
+ * it's best to have buff aligned on a 32-bit boundary
+ */
+__wsum csum_partial(const void *buff, int len, __wsum sum)
+{
+ unsigned long result = do_csum(buff, len);
+
+ /* add in old sum, and carry.. */
+ result += (__force u32)sum;
+ /* 32+c bits -> 32 bits */
+ result = (result & 0xffffffff) + (result >> 32);
+ return (__force __wsum)result;
+}
+
+EXPORT_SYMBOL(csum_partial);
+
+/*
+ * this routine is used for miscellaneous IP-like checksums, mainly
+ * in icmp.c
+ */
+__sum16 ip_compute_csum(const void *buff, int len)
+{
+ return (__force __sum16)~from64to16(do_csum(buff,len));
+}
+EXPORT_SYMBOL(ip_compute_csum);