blob: 9bd1b88a9543fafad6d6f0e500220e7be378e57c [file] [log] [blame]
/*
* Copyright (c) 2013-2015, Wind River Systems, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* @file
* @brief system module for variants with LOAPIC
*
*/
#include <misc/__assert.h>
#include "board.h"
#include <nanokernel.h>
#include <arch/cpu.h>
#include <drivers/ioapic.h>
#include <drivers/loapic.h>
#include <irq.h>
#if !defined(LOAPIC_IRQ_BASE) && !defined (LOAPIC_IRQ_COUNT)
/* Default IA32 system APIC definitions with local APIC IRQs after IO APIC. */
#define LOAPIC_IRQ_BASE CONFIG_IOAPIC_NUM_RTES
#define LOAPIC_IRQ_COUNT 6 /* Default to LOAPIC_TIMER to LOAPIC_ERROR */
#define IS_IOAPIC_IRQ(irq) (irq < LOAPIC_IRQ_BASE)
#define HARDWARE_IRQ_LIMIT ((LOAPIC_IRQ_BASE + LOAPIC_IRQ_COUNT) - 1)
#else
/*
Assumption for boards that define LOAPIC_IRQ_BASE & LOAPIC_IRQ_COUNT that
local APIC IRQs are within IOAPIC RTE range.
*/
#define IS_IOAPIC_IRQ(irq) ((irq < LOAPIC_IRQ_BASE) || \
(irq >= (LOAPIC_IRQ_BASE + LOAPIC_IRQ_COUNT)))
#define HARDWARE_IRQ_LIMIT (CONFIG_IOAPIC_NUM_RTES - 1)
#endif
/* forward declarations */
static int __LocalIntVecAlloc(unsigned int irq, unsigned int priority);
/**
*
* @brief Allocate interrupt vector
*
* This routine is used by the x86's irq_connect_dynamic(). It performs the
* following functions:
*
* a) Allocates a vector satisfying the requested priority. The utility
* routine _IntVecAlloc() provided by the nanokernel will be used to
* perform the the allocation since the local APIC prioritizes interrupts
* as assumed by _IntVecAlloc().
* b) If an interrupt vector can be allocated, the IOAPIC redirection table
* (RED) or the LOAPIC local vector table (LVT) will be updated with the
* allocated interrupt vector.
*
* The board virtualizes IRQs as follows:
*
* - The first CONFIG_IOAPIC_NUM_RTES IRQs are provided by the IOAPIC
* - The remaining IRQs are provided by the LOAPIC.
*
* Thus, for example, if the IOAPIC supports 24 IRQs:
*
* - IRQ0 to IRQ23 map to IOAPIC IRQ0 to IRQ23
* - IRQ24 to IRQ29 map to LOAPIC LVT entries as follows:
*
* IRQ24 -> LOAPIC_TIMER
* IRQ25 -> LOAPIC_THERMAL
* IRQ26 -> LOAPIC_PMC
* IRQ27 -> LOAPIC_LINT0
* IRQ28 -> LOAPIC_LINT1
* IRQ29 -> LOAPIC_ERROR
*
* @param irq virtualized IRQ
* @param priority get vector from <priority> group
* @param flags Interrupt flags
*
* @return the allocated interrupt vector
*
* @internal
* For debug kernels, this routine will return -1 if there are no vectors
* remaining in the specified <priority> level, or if the <priority> or <irq>
* parameters are invalid.
* @endinternal
*/
int _SysIntVecAlloc(
unsigned int irq, /* virtualized IRQ */
unsigned int priority, /* get vector from <priority> group */
uint32_t flags /* interrupt flags */
)
{
int vector;
__ASSERT(priority < 14, "invalid priority");
__ASSERT(irq >= 0 && irq <= HARDWARE_IRQ_LIMIT, "invalid irq line");
vector = __LocalIntVecAlloc(irq, priority);
/*
* Set up the appropriate interrupt controller to generate the allocated
* interrupt vector for the specified IRQ
*/
__ASSERT(vector != -1, "bad vector id");
_SysIntVecProgram(vector, irq, flags);
return vector;
}
/**
*
* @brief Program interrupt controller
*
* This routine programs the interrupt controller with the given vector
* based on the given IRQ parameter.
*
* Drivers call this routine instead of IRQ_CONNECT() when interrupts are
* configured statically.
*
* The Galileo board virtualizes IRQs as follows:
*
* - The first CONFIG_IOAPIC_NUM_RTES IRQs are provided by the IOAPIC so the
* IOAPIC is programmed for these IRQs
* - The remaining IRQs are provided by the LOAPIC and hence the LOAPIC is
* programmed.
*
* @param vector the vector number
* @param irq the virtualized IRQ
* @param flags interrupt flags
*
*/
void _SysIntVecProgram(unsigned int vector, unsigned int irq, uint32_t flags)
{
if (IS_IOAPIC_IRQ(irq)) {
_ioapic_irq_set(irq, vector, flags);
} else {
_loapic_int_vec_set(irq - LOAPIC_IRQ_BASE, vector);
}
}
/**
*
* @brief Enable an individual interrupt (IRQ)
*
* The public interface for enabling/disabling a specific IRQ for the IA-32
* architecture is defined as follows in include/arch/x86/arch.h
*
* extern void irq_enable (unsigned int irq);
* extern void irq_disable (unsigned int irq);
*
* The irq_enable() routine is provided by the interrupt controller driver due
* to the IRQ virtualization that is performed by this platform. See the
* comments in _SysIntVecAlloc() for more information regarding IRQ
* virtualization.
*
* @return N/A
*/
void _arch_irq_enable(unsigned int irq)
{
if (IS_IOAPIC_IRQ(irq)) {
_ioapic_irq_enable(irq);
} else {
_loapic_irq_enable(irq - LOAPIC_IRQ_BASE);
}
}
/**
*
* @brief Disable an individual interrupt (IRQ)
*
* The irq_disable() routine is provided by the interrupt controller driver due
* to the IRQ virtualization that is performed by this platform. See the
* comments in _SysIntVecAlloc() for more information regarding IRQ
* virtualization.
*
* @return N/A
*/
void _arch_irq_disable(unsigned int irq)
{
if (IS_IOAPIC_IRQ(irq)) {
_ioapic_irq_disable(irq);
} else {
_loapic_irq_disable(irq - LOAPIC_IRQ_BASE);
}
}
#ifdef FIXED_HARDWARE_IRQ_TO_VEC_MAPPING
static inline int handle_fixed_mapping(int irq, int *vector)
{
/*
* On this board Hardware IRQs are fixed and not programmable.
*/
*vector = FIXED_HARDWARE_IRQ_TO_VEC_MAPPING(irq);
/* mark vector as allocated */
_IntVecMarkAllocated(*vector);
return *vector;
}
#else
static inline int handle_fixed_mapping(int irq, int *vector)
{
ARG_UNUSED(irq);
ARG_UNUSED(vector);
return 0;
}
#endif
/**
*
* @brief Local allocate interrupt vector.
*
* @returns The allocated interrupt vector
*
*/
static int __LocalIntVecAlloc(
unsigned int irq, /* virtualized IRQ */
unsigned int priority /* get vector from <priority> group */
)
{
int vector;
if (handle_fixed_mapping(irq, &vector)) {
return vector;
}
/*
* Use the nanokernel utility function _IntVecAlloc(). A value of
* -1 will be returned if there are no free vectors in the requested
* priority.
*/
vector = _IntVecAlloc(priority);
__ASSERT(vector != -1, "No free vectors in the requested priority");
return vector;
}