CLINT

group CLINT Driver

Core Local Interruptor (CLINT) driver implementation for Chimera-SDK.

Functions

clint_mtime_t clint_get_mtime(void)

Retrieves the current CLINT mtime value.

Returns:

The current CLINT timer value.

int clint_mtime_less_than(clint_mtime_t a, clint_mtime_t b)

Compares two CLINT mtime values.

Parameters:

  • a – First CLINT time value.

  • b – Second CLINT time value.

Returns:

1 if a is less than b, 0 otherwise.

void clint_spin_until(clint_mtime_t tgt_mtime)

Spins (busy-waits) until the specified CLINT mtime value is reached.

Parameters:

tgt_mtime – Target CLINT time value.

void clint_spin_ticks(uint32_t ticks)

Spins (busy-waits) for a given number of ticks.

Parameters:

ticks – Number of clock cycles to wait.

uint32_t clint_get_core_freq(uint32_t ref_freq, uint32_t ref_time_inv)

Estimates the core frequency based on a reference measurement period.

The parameter ref_time_inv is the inverse of the measurement period.

Parameters:

  • ref_freq – Reference frequency in Hz.

  • ref_time_inv – Inverse of the measurement period.

Returns:

Estimated core frequency in Hz.

void clint_set_mtimecmpx(uint32_t timer_idx, clint_mtime_t value)

Sets the mtimecmp register for a specific timer index.

Parameters:

  • timer_idx – Timer index to configure.

  • value – Target mtimecmp value.

void clint_sleep_until(uint32_t timer_idx, clint_mtime_t tgt_mtime)

Puts the core to sleep until the specified CLINT mtime value is reached.

Parameters:

  • timer_idx – Timer index.

  • tgt_mtime – Target CLINT time value for wakeup.

void clint_sleep_ticks(uint32_t timer_idx, uint32_t ticks)

Puts the core to sleep for a specified number of ticks.

Parameters:

  • timer_idx – Timer index.

  • ticks – Number of clock cycles to sleep.

Variables

const chi_interrupt_api_t default_clint_api

CLINT’s implementation of the generic interrupt-controller API.

Users should use the chi_interrupt_t + interrupt_api abstraction when driving CLINT.

chi_interrupt_t default_clint_inst
struct clint_mtime_t
#include <clint.h>

Platform-specific mtime type definition.

  • In a 64-bit system, clint_mtime_t is typedef’d to uint64_t.

  • In a 32-bit system, clint_mtime_t is a structure with .low and .high members.

32-bit representation of mtime (split into low/high).

Public Members

uint32_t low

Lower 32 bits of mtime.

uint32_t high

Upper 32 bits of mtime.

64-bit CLINT Driver

The 64-bit CLINT driver implements timer and interrupt functionalities using a 64-bit data type (uint64_t) for the mtime register. This configuration is activated when the PLATFORM_IS_64BIT flag is defined.

group 64-bit CLINT Driver

64-bit CLINT driver implementation for Chimera-SDK.

This header provides the declarations for the 64-bit CLINT driver. The generic CLINT HAL API functions (declared in hal/inc/clint.h) are aliased to the 64-bit implementations in this driver.

Defines

PLATFORM_IS_64BIT

Functions

static int clint64_init(const chi_interrupt_t *ctrl)
static int clint64_register_handler(const chi_interrupt_t *ctrl, int irq, chi_irq_handler_t handler, void *arg)
static int clint64_enable_irq(const chi_interrupt_t *ctrl, int irq)
static int clint64_disable_irq(const chi_interrupt_t *ctrl, int irq)
static int clint64_set_priority(const chi_interrupt_t *ctrl, int irq, int priority)
static int clint64_acknowledge(const chi_interrupt_t *ctrl, int irq)
static void clint64_dispatch(const chi_interrupt_t *ctrl)

32-bit CLINT Driver

The 32-bit CLINT driver adapts the timer and sleep functionalities for 32-bit platforms by representing the mtime register as a structure with two 32-bit members (low and high). This approach maintains compatibility with 32-bit systems while delivering equivalent performance and functionality as the 64-bit version.

group 32-bit CLINT Driver

32-bit CLINT driver implementation for Chimera-SDK.

This file provides the implementation of the 32-bit CLINT driver. It includes functions for reading the current time, comparing times, spinning until a target time, and sleeping until a target time.

This header provides the declarations for the 32-bit CLINT driver. The generic CLINT HAL API functions (declared in hal/inc/clint.h) are aliased to the 32-bit implementations in this driver.

Functions

static int clint32_init(const chi_interrupt_t *ctrl)
static int clint32_register_handler(const chi_interrupt_t *ctrl, int irq, chi_irq_handler_t handler, void *arg)
static int clint32_enable_irq(const chi_interrupt_t *ctrl, int irq)
static int clint32_disable_irq(const chi_interrupt_t *ctrl, int irq)
static int clint32_set_priority(const chi_interrupt_t *ctrl, int irq, int prio)
static int clint32_acknowledge(const chi_interrupt_t *ctrl, int irq)
static void clint32_dispatch(const chi_interrupt_t *ctrl)