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diff --git a/scripts/gen-crc-consts.py b/scripts/gen-crc-consts.py
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+++ b/scripts/gen-crc-consts.py
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+#!/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}')