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
  ...

1 files changed, 291 insertions, 0 deletions

diff --git a/scripts/gen-crc-consts.py b/scripts/gen-crc-consts.py
new file mode 100755
index 000000000..f9b44fc3a
--- /dev/null
+++ b/scripts/gen-crc-consts.py
@@ -0,0 +1,291 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0-or-later
+#
+# Script that generates constants for computing the given CRC variant(s).
+#
+# Copyright 2025 Google LLC
+#
+# Author: Eric Biggers <ebiggers@google.com>
+
+import sys
+
+# XOR (add) an iterable of polynomials.
+def xor(iterable):
+    res = 0
+    for val in iterable:
+        res ^= val
+    return res
+
+# Multiply two polynomials.
+def clmul(a, b):
+    return xor(a << i for i in range(b.bit_length()) if (b & (1 << i)) != 0)
+
+# Polynomial division floor(a / b).
+def div(a, b):
+    q = 0
+    while a.bit_length() >= b.bit_length():
+        q ^= 1 << (a.bit_length() - b.bit_length())
+        a ^= b << (a.bit_length() - b.bit_length())
+    return q
+
+# Reduce the polynomial 'a' modulo the polynomial 'b'.
+def reduce(a, b):
+    return a ^ clmul(div(a, b), b)
+
+# Reflect the bits of a polynomial.
+def bitreflect(poly, num_bits):
+    assert poly.bit_length() <= num_bits
+    return xor(((poly >> i) & 1) << (num_bits - 1 - i) for i in range(num_bits))
+
+# Format a polynomial as hex.  Bit-reflect it if the CRC is lsb-first.
+def fmt_poly(variant, poly, num_bits):
+    if variant.lsb:
+        poly = bitreflect(poly, num_bits)
+    return f'0x{poly:0{2*num_bits//8}x}'
+
+# Print a pair of 64-bit polynomial multipliers.  They are always passed in the
+# order [HI64_TERMS, LO64_TERMS] but will be printed in the appropriate order.
+def print_mult_pair(variant, mults):
+    mults = list(mults if variant.lsb else reversed(mults))
+    terms = ['HI64_TERMS', 'LO64_TERMS'] if variant.lsb else ['LO64_TERMS', 'HI64_TERMS']
+    for i in range(2):
+        print(f'\t\t{fmt_poly(variant, mults[i]["val"], 64)},\t/* {terms[i]}: {mults[i]["desc"]} */')
+
+# Pretty-print a polynomial.
+def pprint_poly(prefix, poly):
+    terms = [f'x^{i}' for i in reversed(range(poly.bit_length()))
+             if (poly & (1 << i)) != 0]
+    j = 0
+    while j < len(terms):
+        s = prefix + terms[j] + (' +' if j < len(terms) - 1 else '')
+        j += 1
+        while j < len(terms) and len(s) < 73:
+            s += ' ' + terms[j] + (' +' if j < len(terms) - 1 else '')
+            j += 1
+        print(s)
+        prefix = ' * ' + (' ' * (len(prefix) - 3))
+
+# Print a comment describing constants generated for the given CRC variant.
+def print_header(variant, what):
+    print('/*')
+    s = f'{"least" if variant.lsb else "most"}-significant-bit-first CRC-{variant.bits}'
+    print(f' * {what} generated for {s} using')
+    pprint_poly(' * G(x) = ', variant.G)
+    print(' */')
+
+class CrcVariant:
+    def __init__(self, bits, generator_poly, bit_order):
+        self.bits = bits
+        if bit_order not in ['lsb', 'msb']:
+            raise ValueError('Invalid value for bit_order')
+        self.lsb = bit_order == 'lsb'
+        self.name = f'crc{bits}_{bit_order}_0x{generator_poly:0{(2*bits+7)//8}x}'
+        if self.lsb:
+            generator_poly = bitreflect(generator_poly, bits)
+        self.G = generator_poly ^ (1 << bits)
+
+# Generate tables for CRC computation using the "slice-by-N" method.
+# N=1 corresponds to the traditional byte-at-a-time table.
+def gen_slicebyN_tables(variants, n):
+    for v in variants:
+        print('')
+        print_header(v, f'Slice-by-{n} CRC table')
+        print(f'static const u{v.bits} __maybe_unused {v.name}_table[{256*n}] = {{')
+        s = ''
+        for i in range(256 * n):
+            # The i'th table entry is the CRC of the message consisting of byte
+            # i % 256 followed by i // 256 zero bytes.
+            poly = (bitreflect(i % 256, 8) if v.lsb else i % 256) << (v.bits + 8*(i//256))
+            next_entry = fmt_poly(v, reduce(poly, v.G), v.bits) + ','
+            if len(s + next_entry) > 71:
+                print(f'\t{s}')
+                s = ''
+            s += (' ' if s else '') + next_entry
+        if s:
+            print(f'\t{s}')
+        print('};')
+
+def print_riscv_const(v, bits_per_long, name, val, desc):
+    print(f'\t.{name} = {fmt_poly(v, val, bits_per_long)}, /* {desc} */')
+
+def do_gen_riscv_clmul_consts(v, bits_per_long):
+    (G, n, lsb) = (v.G, v.bits, v.lsb)
+
+    pow_of_x = 3 * bits_per_long - (1 if lsb else 0)
+    print_riscv_const(v, bits_per_long, 'fold_across_2_longs_const_hi',
+                      reduce(1 << pow_of_x, G), f'x^{pow_of_x} mod G')
+    pow_of_x = 2 * bits_per_long - (1 if lsb else 0)
+    print_riscv_const(v, bits_per_long, 'fold_across_2_longs_const_lo',
+                      reduce(1 << pow_of_x, G), f'x^{pow_of_x} mod G')
+
+    pow_of_x = bits_per_long - 1 + n
+    print_riscv_const(v, bits_per_long, 'barrett_reduction_const_1',
+                      div(1 << pow_of_x, G), f'floor(x^{pow_of_x} / G)')
+
+    val = G - (1 << n)
+    desc = f'G - x^{n}'
+    if lsb:
+        val <<= bits_per_long - n
+        desc = f'({desc}) * x^{bits_per_long - n}'
+    print_riscv_const(v, bits_per_long, 'barrett_reduction_const_2', val, desc)
+
+def gen_riscv_clmul_consts(variants):
+    print('')
+    print('struct crc_clmul_consts {');
+    print('\tunsigned long fold_across_2_longs_const_hi;');
+    print('\tunsigned long fold_across_2_longs_const_lo;');
+    print('\tunsigned long barrett_reduction_const_1;');
+    print('\tunsigned long barrett_reduction_const_2;');
+    print('};');
+    for v in variants:
+        print('');
+        if v.bits > 32:
+            print_header(v, 'Constants')
+            print('#ifdef CONFIG_64BIT')
+            print(f'static const struct crc_clmul_consts {v.name}_consts __maybe_unused = {{')
+            do_gen_riscv_clmul_consts(v, 64)
+            print('};')
+            print('#endif')
+        else:
+            print_header(v, 'Constants')
+            print(f'static const struct crc_clmul_consts {v.name}_consts __maybe_unused = {{')
+            print('#ifdef CONFIG_64BIT')
+            do_gen_riscv_clmul_consts(v, 64)
+            print('#else')
+            do_gen_riscv_clmul_consts(v, 32)
+            print('#endif')
+            print('};')
+
+# Generate constants for carryless multiplication based CRC computation.
+def gen_x86_pclmul_consts(variants):
+    # These are the distances, in bits, to generate folding constants for.
+    FOLD_DISTANCES = [2048, 1024, 512, 256, 128]
+
+    for v in variants:
+        (G, n, lsb) = (v.G, v.bits, v.lsb)
+        print('')
+        print_header(v, 'CRC folding constants')
+        print('static const struct {')
+        if not lsb:
+            print('\tu8 bswap_mask[16];')
+        for i in FOLD_DISTANCES:
+            print(f'\tu64 fold_across_{i}_bits_consts[2];')
+        print('\tu8 shuf_table[48];')
+        print('\tu64 barrett_reduction_consts[2];')
+        print(f'}} {v.name}_consts ____cacheline_aligned __maybe_unused = {{')
+
+        # Byte-reflection mask, needed for msb-first CRCs
+        if not lsb:
+            print('\t.bswap_mask = {' + ', '.join(str(i) for i in reversed(range(16))) + '},')
+
+        # Fold constants for all distances down to 128 bits
+        for i in FOLD_DISTANCES:
+            print(f'\t.fold_across_{i}_bits_consts = {{')
+            # Given 64x64 => 128 bit carryless multiplication instructions, two
+            # 64-bit fold constants are needed per "fold distance" i: one for
+            # HI64_TERMS that is basically x^(i+64) mod G and one for LO64_TERMS
+            # that is basically x^i mod G.  The exact values however undergo a
+            # couple adjustments, described below.
+            mults = []
+            for j in [64, 0]:
+                pow_of_x = i + j
+                if lsb:
+                    # Each 64x64 => 128 bit carryless multiplication instruction
+                    # actually generates a 127-bit product in physical bits 0
+                    # through 126, which in the lsb-first case represent the
+                    # coefficients of x^1 through x^127, not x^0 through x^126.
+                    # Thus in the lsb-first case, each such instruction
+                    # implicitly adds an extra factor of x.  The below removes a
+                    # factor of x from each constant to compensate for this.
+                    # For n < 64 the x could be removed from either the reduced
+                    # part or unreduced part, but for n == 64 the reduced part
+                    # is the only option.  Just always use the reduced part.
+                    pow_of_x -= 1
+                # Make a factor of x^(64-n) be applied unreduced rather than
+                # reduced, to cause the product to use only the x^(64-n) and
+                # higher terms and always be zero in the lower terms.  Usually
+                # this makes no difference as it does not affect the product's
+                # congruence class mod G and the constant remains 64-bit, but
+                # part of the final reduction from 128 bits does rely on this
+                # property when it reuses one of the constants.
+                pow_of_x -= 64 - n
+                mults.append({ 'val': reduce(1 << pow_of_x, G) << (64 - n),
+                               'desc': f'(x^{pow_of_x} mod G) * x^{64-n}' })
+            print_mult_pair(v, mults)
+            print('\t},')
+
+        # Shuffle table for handling 1..15 bytes at end
+        print('\t.shuf_table = {')
+        print('\t\t' + (16*'-1, ').rstrip())
+        print('\t\t' + ''.join(f'{i:2}, ' for i in range(16)).rstrip())
+        print('\t\t' + (16*'-1, ').rstrip())
+        print('\t},')
+
+        # Barrett reduction constants for reducing 128 bits to the final CRC
+        print('\t.barrett_reduction_consts = {')
+        mults = []
+
+        val = div(1 << (63+n), G)
+        desc = f'floor(x^{63+n} / G)'
+        if not lsb:
+            val = (val << 1) - (1 << 64)
+            desc = f'({desc} * x) - x^64'
+        mults.append({ 'val': val, 'desc': desc })
+
+        val = G - (1 << n)
+        desc = f'G - x^{n}'
+        if lsb and n == 64:
+            assert (val & 1) != 0  # The x^0 term should always be nonzero.
+            val >>= 1
+            desc = f'({desc} - x^0) / x'
+        else:
+            pow_of_x = 64 - n - (1 if lsb else 0)
+            val <<= pow_of_x
+            desc = f'({desc}) * x^{pow_of_x}'
+        mults.append({ 'val': val, 'desc': desc })
+
+        print_mult_pair(v, mults)
+        print('\t},')
+
+        print('};')
+
+def parse_crc_variants(vars_string):
+    variants = []
+    for var_string in vars_string.split(','):
+        bits, bit_order, generator_poly = var_string.split('_')
+        assert bits.startswith('crc')
+        bits = int(bits.removeprefix('crc'))
+        assert generator_poly.startswith('0x')
+        generator_poly = generator_poly.removeprefix('0x')
+        assert len(generator_poly) % 2 == 0
+        generator_poly = int(generator_poly, 16)
+        variants.append(CrcVariant(bits, generator_poly, bit_order))
+    return variants
+
+if len(sys.argv) != 3:
+    sys.stderr.write(f'Usage: {sys.argv[0]} CONSTS_TYPE[,CONSTS_TYPE]... CRC_VARIANT[,CRC_VARIANT]...\n')
+    sys.stderr.write('  CONSTS_TYPE can be sliceby[1-8], riscv_clmul, or x86_pclmul\n')
+    sys.stderr.write('  CRC_VARIANT is crc${num_bits}_${bit_order}_${generator_poly_as_hex}\n')
+    sys.stderr.write('     E.g. crc16_msb_0x8bb7 or crc32_lsb_0xedb88320\n')
+    sys.stderr.write('     Polynomial must use the given bit_order and exclude x^{num_bits}\n')
+    sys.exit(1)
+
+print('/* SPDX-License-Identifier: GPL-2.0-or-later */')
+print('/*')
+print(' * CRC constants generated by:')
+print(' *')
+print(f' *\t{sys.argv[0]} {" ".join(sys.argv[1:])}')
+print(' *')
+print(' * Do not edit manually.')
+print(' */')
+consts_types = sys.argv[1].split(',')
+variants = parse_crc_variants(sys.argv[2])
+for consts_type in consts_types:
+    if consts_type.startswith('sliceby'):
+        gen_slicebyN_tables(variants, int(consts_type.removeprefix('sliceby')))
+    elif consts_type == 'riscv_clmul':
+        gen_riscv_clmul_consts(variants)
+    elif consts_type == 'x86_pclmul':
+        gen_x86_pclmul_consts(variants)
+    else:
+        raise ValueError(f'Unknown consts_type: {consts_type}')