mirror of https://github.com/Desuuuu/klipper.git
lpc176x: Add hardware PWM support for LPC176x
This adds hardware PWM support for LPC176x processors. Signed-off-by: Michael Kurz <michi.kurz@gmail.com>
This commit is contained in:
parent
d02c80ef08
commit
39188e1cf3
|
@ -12,6 +12,7 @@ config LPC_SELECT
|
|||
select HAVE_GPIO_BITBANGING
|
||||
select HAVE_STRICT_TIMING
|
||||
select HAVE_CHIPID
|
||||
select HAVE_GPIO_HARD_PWM
|
||||
|
||||
config BOARD_DIRECTORY
|
||||
string
|
||||
|
|
|
@ -22,6 +22,7 @@ src-$(CONFIG_HAVE_GPIO_SPI) += lpc176x/spi.c
|
|||
src-$(CONFIG_USBSERIAL) += lpc176x/usbserial.c lpc176x/chipid.c
|
||||
src-$(CONFIG_USBSERIAL) += generic/usb_cdc.c
|
||||
src-$(CONFIG_SERIAL) += lpc176x/serial.c generic/serial_irq.c
|
||||
src-$(CONFIG_HAVE_GPIO_HARD_PWM) += lpc176x/hard_pwm.c
|
||||
|
||||
# Build the additional bin output file
|
||||
target-y += $(OUT)klipper.bin
|
||||
|
|
|
@ -21,6 +21,13 @@ struct gpio_in gpio_in_setup(uint8_t pin, int8_t pull_up);
|
|||
void gpio_in_reset(struct gpio_in g, int8_t pull_up);
|
||||
uint8_t gpio_in_read(struct gpio_in g);
|
||||
|
||||
struct gpio_pwm {
|
||||
void *reg;
|
||||
uint8_t channel;
|
||||
};
|
||||
struct gpio_pwm gpio_pwm_setup(uint8_t pin, uint32_t cycle_time, uint8_t val);
|
||||
void gpio_pwm_write(struct gpio_pwm g, uint32_t val);
|
||||
|
||||
struct gpio_adc {
|
||||
uint32_t chan;
|
||||
};
|
||||
|
|
|
@ -0,0 +1,97 @@
|
|||
// Hardware PWM support on lpc176x
|
||||
//
|
||||
// Copyright (C) 2021 Michael Kurz <michi.kurz@gmail.com>
|
||||
//
|
||||
// This file may be distributed under the terms of the GNU GPLv3 license.
|
||||
|
||||
#include "autoconf.h" // CONFIG_CLOCK_FREQ
|
||||
#include "board/irq.h" // irq_save
|
||||
#include "command.h" // shutdown
|
||||
#include "gpio.h" // gpio_pwm_write
|
||||
#include "internal.h" // GPIO
|
||||
#include "sched.h" // sched_shutdown
|
||||
|
||||
#define MAX_PWM 255
|
||||
DECL_CONSTANT("PWM_MAX", MAX_PWM);
|
||||
|
||||
struct gpio_pwm_info {
|
||||
uint8_t pin, channel, function;
|
||||
void *reg;
|
||||
};
|
||||
|
||||
static const struct gpio_pwm_info pwm_regs[] = {
|
||||
{GPIO(1, 18), 1, 2, (void*)&LPC_PWM1->MR1},
|
||||
{GPIO(2, 0), 1, 1, (void*)&LPC_PWM1->MR1},
|
||||
{GPIO(1, 20), 2, 2, (void*)&LPC_PWM1->MR2},
|
||||
{GPIO(2, 1), 2, 1, (void*)&LPC_PWM1->MR2},
|
||||
{GPIO(3, 25), 2, 3, (void*)&LPC_PWM1->MR2},
|
||||
{GPIO(1, 21), 3, 2, (void*)&LPC_PWM1->MR3},
|
||||
{GPIO(2, 2), 3, 1, (void*)&LPC_PWM1->MR3},
|
||||
{GPIO(3, 26), 3, 3, (void*)&LPC_PWM1->MR3},
|
||||
{GPIO(1, 23), 4, 2, (void*)&LPC_PWM1->MR4},
|
||||
{GPIO(2, 3), 4, 1, (void*)&LPC_PWM1->MR4},
|
||||
{GPIO(1, 24), 5, 2, (void*)&LPC_PWM1->MR5},
|
||||
{GPIO(2, 4), 5, 1, (void*)&LPC_PWM1->MR5},
|
||||
{GPIO(1, 26), 6, 2, (void*)&LPC_PWM1->MR6},
|
||||
{GPIO(2, 5), 6, 1, (void*)&LPC_PWM1->MR6}
|
||||
};
|
||||
|
||||
struct gpio_pwm
|
||||
gpio_pwm_setup(uint8_t pin, uint32_t cycle_time, uint8_t val) {
|
||||
// Find pin in pwm_regs table
|
||||
const struct gpio_pwm_info* p = pwm_regs;
|
||||
for (;; p++) {
|
||||
if (p >= &pwm_regs[ARRAY_SIZE(pwm_regs)])
|
||||
shutdown("Not a valid PWM pin");
|
||||
if (p->pin == pin)
|
||||
break;
|
||||
}
|
||||
|
||||
// Map cycle_time to pwm clock divisor
|
||||
uint32_t clock_div = CONFIG_CLOCK_FREQ / get_pclock_frequency(PCLK_PWM1);
|
||||
uint32_t prescaler = (cycle_time / clock_div) / (MAX_PWM - 1);
|
||||
if (prescaler > 0) {
|
||||
prescaler -= 1;
|
||||
}
|
||||
|
||||
gpio_peripheral(p->pin, p->function, 0);
|
||||
|
||||
// Enable clock
|
||||
if (!is_enabled_pclock(PCLK_PWM1)) {
|
||||
enable_pclock(PCLK_PWM1);
|
||||
}
|
||||
|
||||
if (LPC_PWM1->TCR & 1) {
|
||||
if (LPC_PWM1->PR != prescaler) {
|
||||
shutdown("PWM already programmed at different speed");
|
||||
}
|
||||
} else {
|
||||
LPC_PWM1->PR = (uint16_t) prescaler;
|
||||
LPC_PWM1->MCR = 2;
|
||||
LPC_PWM1->MR0 = MAX_PWM - 1;
|
||||
LPC_PWM1->LER |= 1 << 0;
|
||||
LPC_PWM1->TCR = 0x2; // Reset PWM
|
||||
LPC_PWM1->TCR = 0x8; // Enable PWM mode
|
||||
}
|
||||
|
||||
if (LPC_PWM1->PCR & (1 << (p->channel + 8))) {
|
||||
shutdown("PWM output already in use");
|
||||
}
|
||||
|
||||
struct gpio_pwm channel = {.reg = p->reg, .channel = p->channel};
|
||||
gpio_pwm_write(channel, val);
|
||||
|
||||
// Enable channel
|
||||
LPC_PWM1->PCR |= (1 << (p->channel + 8));
|
||||
|
||||
// Enable PWM peripheral
|
||||
LPC_PWM1->TCR |= 0x1;
|
||||
|
||||
return channel;
|
||||
}
|
||||
|
||||
void
|
||||
gpio_pwm_write(struct gpio_pwm g, uint32_t val) {
|
||||
*(volatile uint32_t*) g.reg = val;
|
||||
LPC_PWM1->LER |= (1 << g.channel);
|
||||
}
|
|
@ -10,6 +10,7 @@
|
|||
|
||||
#define PCLK_TIMER0 1
|
||||
#define PCLK_UART0 3
|
||||
#define PCLK_PWM1 6
|
||||
#define PCLK_I2C0 7
|
||||
#define PCLK_SSP1 10
|
||||
#define PCLK_ADC 12
|
||||
|
|
Loading…
Reference in New Issue