| /* |
| * Copyright 2017 Advanced Micro Devices, Inc. |
| * |
| * 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 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 COPYRIGHT HOLDER(S) OR AUTHOR(S) 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. |
| * |
| * Authors: AMD |
| * |
| */ |
| #include "dm_services.h" |
| #include "custom_float.h" |
| |
| |
| static bool build_custom_float( |
| struct fixed31_32 value, |
| const struct custom_float_format *format, |
| bool *negative, |
| uint32_t *mantissa, |
| uint32_t *exponenta) |
| { |
| uint32_t exp_offset = (1 << (format->exponenta_bits - 1)) - 1; |
| |
| const struct fixed31_32 mantissa_constant_plus_max_fraction = |
| dc_fixpt_from_fraction( |
| (1LL << (format->mantissa_bits + 1)) - 1, |
| 1LL << format->mantissa_bits); |
| |
| struct fixed31_32 mantiss; |
| |
| if (dc_fixpt_eq( |
| value, |
| dc_fixpt_zero)) { |
| *negative = false; |
| *mantissa = 0; |
| *exponenta = 0; |
| return true; |
| } |
| |
| if (dc_fixpt_lt( |
| value, |
| dc_fixpt_zero)) { |
| *negative = format->sign; |
| value = dc_fixpt_neg(value); |
| } else { |
| *negative = false; |
| } |
| |
| if (dc_fixpt_lt( |
| value, |
| dc_fixpt_one)) { |
| uint32_t i = 1; |
| |
| do { |
| value = dc_fixpt_shl(value, 1); |
| ++i; |
| } while (dc_fixpt_lt( |
| value, |
| dc_fixpt_one)); |
| |
| --i; |
| |
| if (exp_offset <= i) { |
| *mantissa = 0; |
| *exponenta = 0; |
| return true; |
| } |
| |
| *exponenta = exp_offset - i; |
| } else if (dc_fixpt_le( |
| mantissa_constant_plus_max_fraction, |
| value)) { |
| uint32_t i = 1; |
| |
| do { |
| value = dc_fixpt_shr(value, 1); |
| ++i; |
| } while (dc_fixpt_lt( |
| mantissa_constant_plus_max_fraction, |
| value)); |
| |
| *exponenta = exp_offset + i - 1; |
| } else { |
| *exponenta = exp_offset; |
| } |
| |
| mantiss = dc_fixpt_sub( |
| value, |
| dc_fixpt_one); |
| |
| if (dc_fixpt_lt( |
| mantiss, |
| dc_fixpt_zero) || |
| dc_fixpt_lt( |
| dc_fixpt_one, |
| mantiss)) |
| mantiss = dc_fixpt_zero; |
| else |
| mantiss = dc_fixpt_shl( |
| mantiss, |
| format->mantissa_bits); |
| |
| *mantissa = dc_fixpt_floor(mantiss); |
| |
| return true; |
| } |
| |
| static bool setup_custom_float( |
| const struct custom_float_format *format, |
| bool negative, |
| uint32_t mantissa, |
| uint32_t exponenta, |
| uint32_t *result) |
| { |
| uint32_t i = 0; |
| uint32_t j = 0; |
| |
| uint32_t value = 0; |
| |
| /* verification code: |
| * once calculation is ok we can remove it |
| */ |
| |
| const uint32_t mantissa_mask = |
| (1 << (format->mantissa_bits + 1)) - 1; |
| |
| const uint32_t exponenta_mask = |
| (1 << (format->exponenta_bits + 1)) - 1; |
| |
| if (mantissa & ~mantissa_mask) { |
| BREAK_TO_DEBUGGER(); |
| mantissa = mantissa_mask; |
| } |
| |
| if (exponenta & ~exponenta_mask) { |
| BREAK_TO_DEBUGGER(); |
| exponenta = exponenta_mask; |
| } |
| |
| /* end of verification code */ |
| |
| while (i < format->mantissa_bits) { |
| uint32_t mask = 1 << i; |
| |
| if (mantissa & mask) |
| value |= mask; |
| |
| ++i; |
| } |
| |
| while (j < format->exponenta_bits) { |
| uint32_t mask = 1 << j; |
| |
| if (exponenta & mask) |
| value |= mask << i; |
| |
| ++j; |
| } |
| |
| if (negative && format->sign) |
| value |= 1 << (i + j); |
| |
| *result = value; |
| |
| return true; |
| } |
| |
| bool convert_to_custom_float_format( |
| struct fixed31_32 value, |
| const struct custom_float_format *format, |
| uint32_t *result) |
| { |
| uint32_t mantissa; |
| uint32_t exponenta; |
| bool negative; |
| |
| return build_custom_float( |
| value, format, &negative, &mantissa, &exponenta) && |
| setup_custom_float( |
| format, negative, mantissa, exponenta, result); |
| } |
| |
| |