Better handling of DELAY_NS and DELAY_US (#10716)
Co-Authored-By: ejtagle <ejtagle@hotmail.com>2.0.x
Scott Lahteine
7 years ago
committed by
GitHub
parent
f5aaa2d6c0
commit
a1062eec5b
@ -0,0 +1,133 @@
|
||||
/**
|
||||
* Marlin 3D Printer Firmware
|
||||
* Copyright (C) 2016 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
|
||||
*
|
||||
* Based on Sprinter and grbl.
|
||||
* Copyright (C) 2011 Camiel Gubbels / Erik van der Zalm
|
||||
*
|
||||
* 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/>.
|
||||
*
|
||||
*/
|
||||
|
||||
/**
|
||||
|
||||
Busy wait delay Cycles routines:
|
||||
|
||||
DELAY_CYCLES(count): Delay execution in cycles
|
||||
DELAY_NS(count): Delay execution in nanoseconds
|
||||
DELAY_US(count): Delay execution in microseconds
|
||||
|
||||
*/
|
||||
|
||||
#ifndef MARLIN_DELAY_H
|
||||
#define MARLIN_DELAY_H
|
||||
|
||||
#if defined(__arm__) || defined(__thumb__)
|
||||
|
||||
/* https://blueprints.launchpad.net/gcc-arm-embedded/+spec/delay-cycles */
|
||||
|
||||
#define nop() __asm__ __volatile__("nop;\n\t":::)
|
||||
|
||||
FORCE_INLINE static void __delay_4cycles(uint32_t cy) { // +1 cycle
|
||||
#if ARCH_PIPELINE_RELOAD_CYCLES < 2
|
||||
#define EXTRA_NOP_CYCLES A("nop")
|
||||
#else
|
||||
#define EXTRA_NOP_CYCLES ""
|
||||
#endif
|
||||
|
||||
__asm__ __volatile__(
|
||||
A(".syntax unified") // is to prevent CM0,CM1 non-unified syntax
|
||||
L("1")
|
||||
A("subs %[cnt],#1")
|
||||
EXTRA_NOP_CYCLES
|
||||
A("bne 1b")
|
||||
: [cnt]"+r"(cy) // output: +r means input+output
|
||||
: // input:
|
||||
: "cc" // clobbers:
|
||||
);
|
||||
}
|
||||
|
||||
/* ---------------- Delay in cycles */
|
||||
FORCE_INLINE static void DELAY_CYCLES(uint32_t x) {
|
||||
|
||||
if (__builtin_constant_p(x)) {
|
||||
#define MAXNOPS 4
|
||||
|
||||
if (x <= (MAXNOPS)) {
|
||||
switch (x) { case 4: nop(); case 3: nop(); case 2: nop(); case 1: nop(); }
|
||||
}
|
||||
else { // because of +1 cycle inside delay_4cycles
|
||||
const uint32_t rem = (x - 1) % (MAXNOPS);
|
||||
switch (rem) { case 3: nop(); case 2: nop(); case 1: nop(); }
|
||||
if ((x = (x - 1) / (MAXNOPS)))
|
||||
__delay_4cycles(x); // if need more then 4 nop loop is more optimal
|
||||
}
|
||||
#undef MAXNOPS
|
||||
}
|
||||
else
|
||||
__delay_4cycles(x / 4);
|
||||
}
|
||||
#undef nop
|
||||
|
||||
#elif defined(__AVR__)
|
||||
|
||||
#define nop() __asm__ __volatile__("nop;\n\t":::)
|
||||
|
||||
FORCE_INLINE static void __delay_4cycles(uint8_t cy) {
|
||||
__asm__ __volatile__(
|
||||
L("1")
|
||||
A("dec %[cnt]")
|
||||
A("nop")
|
||||
A("brne 1b")
|
||||
: [cnt] "+r"(cy) // output: +r means input+output
|
||||
: // input:
|
||||
: "cc" // clobbers:
|
||||
);
|
||||
}
|
||||
|
||||
/* ---------------- Delay in cycles */
|
||||
FORCE_INLINE static void DELAY_CYCLES(uint16_t x) {
|
||||
|
||||
if (__builtin_constant_p(x)) {
|
||||
#define MAXNOPS 4
|
||||
|
||||
if (x <= (MAXNOPS)) {
|
||||
switch (x) { case 4: nop(); case 3: nop(); case 2: nop(); case 1: nop(); }
|
||||
}
|
||||
else {
|
||||
const uint32_t rem = (x) % (MAXNOPS);
|
||||
switch (rem) { case 3: nop(); case 2: nop(); case 1: nop(); }
|
||||
if ((x = (x) / (MAXNOPS)))
|
||||
__delay_4cycles(x); // if need more then 4 nop loop is more optimal
|
||||
}
|
||||
|
||||
#undef MAXNOPS
|
||||
}
|
||||
else
|
||||
__delay_4cycles(x / 4);
|
||||
}
|
||||
#undef nop
|
||||
|
||||
#else
|
||||
#error "Unsupported MCU architecture"
|
||||
#endif
|
||||
|
||||
/* ---------------- Delay in nanoseconds */
|
||||
#define DELAY_NS(x) DELAY_CYCLES( (x) * (F_CPU/1000000L) / 1000L )
|
||||
|
||||
/* ---------------- Delay in microseconds */
|
||||
#define DELAY_US(x) DELAY_CYCLES( (x) * (F_CPU/1000000L) )
|
||||
|
||||
#endif // MARLIN_DELAY_H
|
||||
|
||||
Loading…
Reference in New Issue