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| author | Joel Challis <git@zvecr.com> | 2021-11-19 18:41:02 +0000 |
|---|---|---|
| committer | GitHub <noreply@github.com> | 2021-11-19 10:41:02 -0800 |
| commit | 2728603fe6d73e805a539d337fd01051c46ca806 (patch) | |
| tree | 5c83ffc7efa112da870bd5d8502a9d91d4792f35 /platforms/chibios/_wait.c | |
| parent | 43b9e23bae12916d5161f03700c9bfe46737324b (diff) | |
Move tmk_core/common/<plat> (#13918)
Diffstat (limited to 'platforms/chibios/_wait.c')
| -rw-r--r-- | platforms/chibios/_wait.c | 89 |
1 files changed, 89 insertions, 0 deletions
diff --git a/platforms/chibios/_wait.c b/platforms/chibios/_wait.c new file mode 100644 index 0000000000..1fbea2dd5e --- /dev/null +++ b/platforms/chibios/_wait.c @@ -0,0 +1,89 @@ +/* Copyright 2021 QMK + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#ifndef __OPTIMIZE__ +# pragma message "Compiler optimizations disabled; wait_cpuclock() won't work as designed" +#endif + +#define CLOCK_DELAY_NOP8 "nop\n\t nop\n\t nop\n\t nop\n\t nop\n\t nop\n\t nop\n\t nop\n\t" + +__attribute__((always_inline)) static inline void wait_cpuclock(unsigned int n) { /* n: 1..135 */ + /* The argument n must be a constant expression. + * That way, compiler optimization will remove unnecessary code. */ + if (n < 1) { + return; + } + if (n > 8) { + unsigned int n8 = n / 8; + n = n - n8 * 8; + switch (n8) { + case 16: + asm volatile(CLOCK_DELAY_NOP8::: "memory"); + case 15: + asm volatile(CLOCK_DELAY_NOP8::: "memory"); + case 14: + asm volatile(CLOCK_DELAY_NOP8::: "memory"); + case 13: + asm volatile(CLOCK_DELAY_NOP8::: "memory"); + case 12: + asm volatile(CLOCK_DELAY_NOP8::: "memory"); + case 11: + asm volatile(CLOCK_DELAY_NOP8::: "memory"); + case 10: + asm volatile(CLOCK_DELAY_NOP8::: "memory"); + case 9: + asm volatile(CLOCK_DELAY_NOP8::: "memory"); + case 8: + asm volatile(CLOCK_DELAY_NOP8::: "memory"); + case 7: + asm volatile(CLOCK_DELAY_NOP8::: "memory"); + case 6: + asm volatile(CLOCK_DELAY_NOP8::: "memory"); + case 5: + asm volatile(CLOCK_DELAY_NOP8::: "memory"); + case 4: + asm volatile(CLOCK_DELAY_NOP8::: "memory"); + case 3: + asm volatile(CLOCK_DELAY_NOP8::: "memory"); + case 2: + asm volatile(CLOCK_DELAY_NOP8::: "memory"); + case 1: + asm volatile(CLOCK_DELAY_NOP8::: "memory"); + case 0: + break; + } + } + switch (n) { + case 8: + asm volatile("nop" ::: "memory"); + case 7: + asm volatile("nop" ::: "memory"); + case 6: + asm volatile("nop" ::: "memory"); + case 5: + asm volatile("nop" ::: "memory"); + case 4: + asm volatile("nop" ::: "memory"); + case 3: + asm volatile("nop" ::: "memory"); + case 2: + asm volatile("nop" ::: "memory"); + case 1: + asm volatile("nop" ::: "memory"); + case 0: + break; + } +} |