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https://github.com/brain-hackers/u-boot-brain
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![Tom Rini](/assets/img/avatar_default.png)
When U-Boot started using SPDX tags we were among the early adopters and there weren't a lot of other examples to borrow from. So we picked the area of the file that usually had a full license text and replaced it with an appropriate SPDX-License-Identifier: entry. Since then, the Linux Kernel has adopted SPDX tags and they place it as the very first line in a file (except where shebangs are used, then it's second line) and with slightly different comment styles than us. In part due to community overlap, in part due to better tag visibility and in part for other minor reasons, switch over to that style. This commit changes all instances where we have a single declared license in the tag as both the before and after are identical in tag contents. There's also a few places where I found we did not have a tag and have introduced one. Signed-off-by: Tom Rini <trini@konsulko.com>
113 lines
2.1 KiB
C
113 lines
2.1 KiB
C
// SPDX-License-Identifier: BSD-3-Clause
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/*
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* This file is copied from the coreboot repository as part of
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* the libpayload project:
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*
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* Copyright 2014 Google Inc.
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*/
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#include <common.h>
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union overlay64 {
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u64 longw;
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struct {
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u32 lower;
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u32 higher;
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} words;
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};
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u64 __ashldi3(u64 num, unsigned int shift)
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{
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union overlay64 output;
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output.longw = num;
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if (shift >= 32) {
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output.words.higher = output.words.lower << (shift - 32);
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output.words.lower = 0;
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} else {
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if (!shift)
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return num;
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output.words.higher = (output.words.higher << shift) |
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(output.words.lower >> (32 - shift));
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output.words.lower = output.words.lower << shift;
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}
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return output.longw;
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}
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u64 __lshrdi3(u64 num, unsigned int shift)
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{
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union overlay64 output;
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output.longw = num;
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if (shift >= 32) {
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output.words.lower = output.words.higher >> (shift - 32);
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output.words.higher = 0;
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} else {
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if (!shift)
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return num;
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output.words.lower = output.words.lower >> shift |
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(output.words.higher << (32 - shift));
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output.words.higher = output.words.higher >> shift;
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}
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return output.longw;
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}
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#define MAX_32BIT_UINT ((((u64)1) << 32) - 1)
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static u64 _64bit_divide(u64 dividend, u64 divider, u64 *rem_p)
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{
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u64 result = 0;
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/*
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* If divider is zero - let the rest of the system care about the
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* exception.
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*/
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if (!divider)
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return 1 / (u32)divider;
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/* As an optimization, let's not use 64 bit division unless we must. */
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if (dividend <= MAX_32BIT_UINT) {
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if (divider > MAX_32BIT_UINT) {
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result = 0;
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if (rem_p)
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*rem_p = divider;
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} else {
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result = (u32)dividend / (u32)divider;
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if (rem_p)
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*rem_p = (u32)dividend % (u32)divider;
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}
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return result;
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}
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while (divider <= dividend) {
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u64 locald = divider;
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u64 limit = __lshrdi3(dividend, 1);
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int shifts = 0;
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while (locald <= limit) {
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shifts++;
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locald = locald + locald;
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}
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result |= __ashldi3(1, shifts);
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dividend -= locald;
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}
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if (rem_p)
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*rem_p = dividend;
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return result;
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}
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u64 __udivdi3(u64 num, u64 den)
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{
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return _64bit_divide(num, den, NULL);
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}
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u64 __umoddi3(u64 num, u64 den)
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{
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u64 v = 0;
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_64bit_divide(num, den, &v);
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return v;
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}
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