From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:49:45 +0200 Subject: Adding upstream version 6.1.76. Signed-off-by: Daniel Baumann --- drivers/gpu/drm/i915/selftests/i915_random.c | 109 +++++++++++++++++++++++++++ 1 file changed, 109 insertions(+) create mode 100644 drivers/gpu/drm/i915/selftests/i915_random.c (limited to 'drivers/gpu/drm/i915/selftests/i915_random.c') diff --git a/drivers/gpu/drm/i915/selftests/i915_random.c b/drivers/gpu/drm/i915/selftests/i915_random.c new file mode 100644 index 000000000..abdfadcf6 --- /dev/null +++ b/drivers/gpu/drm/i915/selftests/i915_random.c @@ -0,0 +1,109 @@ +/* + * Copyright © 2016 Intel Corporation + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the next + * paragraph) shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS + * IN THE SOFTWARE. + * + */ + +#include +#include +#include +#include +#include + +#include "i915_random.h" +#include "i915_utils.h" + +u64 i915_prandom_u64_state(struct rnd_state *rnd) +{ + u64 x; + + x = prandom_u32_state(rnd); + x <<= 32; + x |= prandom_u32_state(rnd); + + return x; +} + +void i915_prandom_shuffle(void *arr, size_t elsz, size_t count, + struct rnd_state *state) +{ + char stack[128]; + + if (WARN_ON(elsz > sizeof(stack) || count > U32_MAX)) + return; + + if (!elsz || !count) + return; + + /* Fisher-Yates shuffle courtesy of Knuth */ + while (--count) { + size_t swp; + + swp = i915_prandom_u32_max_state(count + 1, state); + if (swp == count) + continue; + + memcpy(stack, arr + count * elsz, elsz); + memcpy(arr + count * elsz, arr + swp * elsz, elsz); + memcpy(arr + swp * elsz, stack, elsz); + } +} + +void i915_random_reorder(unsigned int *order, unsigned int count, + struct rnd_state *state) +{ + i915_prandom_shuffle(order, sizeof(*order), count, state); +} + +unsigned int *i915_random_order(unsigned int count, struct rnd_state *state) +{ + unsigned int *order, i; + + order = kmalloc_array(count, sizeof(*order), + GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_NOWARN); + if (!order) + return order; + + for (i = 0; i < count; i++) + order[i] = i; + + i915_random_reorder(order, count, state); + return order; +} + +u64 igt_random_offset(struct rnd_state *state, + u64 start, u64 end, + u64 len, u64 align) +{ + u64 range, addr; + + BUG_ON(range_overflows(start, len, end)); + BUG_ON(round_up(start, align) > round_down(end - len, align)); + + range = round_down(end - len, align) - round_up(start, align); + if (range) { + addr = i915_prandom_u64_state(state); + div64_u64_rem(addr, range, &addr); + start += addr; + } + + return round_up(start, align); +} -- cgit v1.2.3