/****************************************************************************
* arch/arm/src/sama5/sam_irq.c
*
* Copyright (C) 2013 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdint.h>
#include <debug.h>
#include <nuttx/irq.h>
#include <nuttx/arch.h>
#include <arch/irq.h>
#include "up_arch.h"
#include "os_internal.h"
#include "up_internal.h"
#ifdef CONFIG_PIO_IRQ
# include "sam_gpio.h"
#endif
#include "chip/sam_aic.h"
#include "chip/sam_matrix.h"
#include "chip/sam_aximx.h"
#include "sam_irq.h"
/****************************************************************************
* Definitions
****************************************************************************/
/* Enable NVIC debug features that are probably only desireable during
* bringup
*/
#undef SAM_IRQ_DEBUG
/****************************************************************************
* Public Data
****************************************************************************/
volatile uint32_t *current_regs;
/****************************************************************************
* Private Data
****************************************************************************/
static const uint8_t g_srctype[SCRTYPE_NTYPES] =
{
0, 0, 1, 1, 2, 3
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: sam_dumpaic
*
* Description:
* Dump some interesting AIC registers
*
****************************************************************************/
#if defined(SAM_IRQ_DEBUG) && defined (CONFIG_DEBUG)
static void sam_dumpaic(const char *msg, int irq)
{
irqstate_t flags;
flags = irqsave();
slldbg("AIC (%s, irq=%d):\n", msg, irq);
/* Select the register set associated with this irq */
putreg32(irq, SAM_AIC_SSR)
/* Then dump all of the (readable) register contents */
slldbg(" SSR: %08x SMR: %08x SVR: %08x IVR: %08x\n",
getreg32(SAM_AIC_SSR), getreg32(SAM_AIC_SMR),
getreg32(SAM_AIC_SVR), getreg32(SAM_AIC_IVR));
slldbg(" FVR: %08x ISR: %08x\n",
getreg32(SAM_AIC_FVR), getreg32(SAM_AIC_ISR));
slldbg(" IPR: %08x %08x %08x %08x\n",
getreg32(SAM_AIC_IPR0), getreg32(SAM_AIC_IPR1),
getreg32(SAM_AIC_IPR2), getreg32(SAM_AIC_IPR3));
slldbg(" IMR: %08x CISR: %08x SPU: %08x FFSR: %08x\n",
getreg32(SAM_AIC_IMR), getreg32(SAM_AIC_CISR),
getreg32(SAM_AIC_SPU), getreg32(SAM_AIC_FFSR));
slldbg(" DCR: %08x WPMR: %08x WPMR: %08x\n",
getreg32(SAM_AIC_DCR), getreg32(SAM_AIC_WPMR),
getreg32(SAM_AIC_WPMR));
irqrestore(flags);
}
#else
# define sam_dumpaic(msg, irq)
#endif
/****************************************************************************
* Name: sam_spurious
*
* Description:
* Spurious interrupt handler.
*
* Paragraph 17.8.6, Spurious Interrupt: "The Advanced Interrupt Controller
* features protection against spurious interrupts. A spurious interrupt is
* defined as being the assertion of an interrupt source long enough for the
* AIC to assert the nIRQ, but no longer present when AIC_IVR is read. This
* is most prone to occur when:
*
* o An external interrupt source is programmed in level-sensitive mode
* and an active level occurs for only a short time.
* o An internal interrupt source is programmed in level sensitive and
* the output signal of the corresponding embedded peripheral is
* activated for a short time. (As in the case for the Watchdog.)
* o An interrupt occurs just a few cycles before the software begins to
* mask it, thus resulting in a pulse on the interrupt source.
*
* "The AIC detects a spurious interrupt at the time the AIC_IVR is read
* while no enabled interrupt source is pending. When this happens, the AIC
* returns the value stored by the programmer in AIC_SPU (Spurious Vector
* Register). The programmer must store the address of a spurious interrupt
* handler in AIC_SPU as part of the application, to enable an as fast as
* possible return to the normal execution flow. This handler writes in
* AIC_EOICR and performs a return from interrupt."
*
****************************************************************************/
static void sam_spurious(void)
{
/* This is probably irrevelant since true vectored interrupts are not used
* in this implementation. The value of AIC_IVR is ignored.
*/
lldbg("Spurious interrupt\n");
PANIC();
}
/****************************************************************************
* Name: sam_fiqhandler
*
* Description:
* Default FIQ interrupt handler.
*
****************************************************************************/
static void sam_fiqhandler(void)
{
/* This is probably irrevelant since true vectored interrupts are not used
* in this implementation. The value of AIC_IVR is ignored.
*/
lldbg("FIQ\n");
PANIC();
}
/****************************************************************************
* Name: sam_irqhandler
*
* Description:
* Default IRQ interrupt handler.
*
****************************************************************************/
static void sam_irqhandler( void )
{
/* This is probably irrevelant since true vectored interrupts are not used
* in this implementation. The value of AIC_IVR is ignored.
*/
lldbg("IRQ\n");
PANIC();
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: up_irqinitialize
*
* Description:
* This function is called by up_initialize() during the bring-up of the
* system. It is the responsibility of this function to but the interrupt
* subsystem into the working and ready state.
*
****************************************************************************/
void up_irqinitialize(void)
{
int i;
/* The following operations need to be atomic, but since this function is
* called early in the intialization sequence, we expect to have exclusive
* access to the AIC.
*/
/* Unprotect SMR, SVR, SPU and DCR register */
putreg32(AIC_WPMR_WPKEY, SAM_AIC_WPMR);
/* Configure the FIQ and the IRQs. */
for (i = 0; i < SAM_IRQ_NINT; i++)
{
/* Select the interrupt registers */
putreg32(i, SAM_AIC_SSR);
/* Disable the interrupt */
putreg32(AIC_IDCR_INTD, SAM_AIC_IDCR);
/* Set the (unused) FIQ/IRQ handler */
if (i == SAM_PID_FIQ)
{
putreg32((uint32_t)sam_fiqhandler, SAM_AIC_SVR);
}
else
{
putreg32((uint32_t)sam_irqhandler, SAM_AIC_SVR);
}
/* Set the default interrupt priority */
putreg32(SAM_DEFAULT_PRIOR, SAM_AIC_SMR);
/* Clear any pending interrupt */
putreg32(AIC_ICCR_INTCLR, SAM_AIC_ICCR);
}
/* Set the (unused) spurious interrupt handler */
putreg32((uint32_t)sam_spurious, SAM_AIC_SPU);
/* Perform 8 interrupt acknowledgements by writing any value to the
* EOICR register.
*/
for (i = 0; i < 8 ; i++)
{
putreg32(AIC_EOICR_ENDIT, SAM_AIC_EOICR);
}
/* Restore protection and the interrupt state */
putreg32(AIC_WPMR_WPKEY | AIC_WPMR_WPEN, SAM_AIC_WPMR);
/* Set remap state 0:
*
* Boot state: ROM is seen at address 0x00000000
* Remap State 0: SRAM is seen at address 0x00000000 (through AHB slave
* interface) instead of ROM.
* Remap State 1: HEBI is seen at address 0x00000000 (through AHB slave
* interface) instead of ROM for external boot.
*/
putreg32(MATRIX_MRCR_RCB0, SAM_MATRIX_MRCR); /* Enable remap */
putreg32(AXIMX_REMAP_REMAP0, SAM_AXIMX_REMAP); /* Remap SRAM */
/* currents_regs is non-NULL only while processing an interrupt */
current_regs = NULL;
#ifndef CONFIG_SUPPRESS_INTERRUPTS
/* Initialize logic to support a second level of interrupt decoding for
* PIO pins.
*/
#ifdef CONFIG_PIO_IRQ
sam_pioirqinitialize();
#endif
/* And finally, enable interrupts */
(void)irqenable();
#endif
}
/****************************************************************************
* Name: up_decodeirq
*
* Description:
* This function is called from the IRQ vector handler in arm_vectors.S.
* At this point, the interrupt has been taken and the registers have
* been saved on the stack. This function simply needs to determine the
* the irq number of the interrupt and then to call up_doirq to dispatch
* the interrupt.
*
* Input paramters:
* regs - A pointer to the register save area on the stack.
*
****************************************************************************/
void up_decodeirq(uint32_t *regs)
{
uint32_t regval;
/* Paragraph 17.8.5 Protect Mode: "The Protect Mode permits reading the
* Interrupt Vector Register without performing the associated automatic
* operations. ... Writing PROT in AIC_DCR (Debug Control Register) at 0x1
* enables the Protect Mode.
*
* "When the Protect Mode is enabled, the AIC performs interrupt stacking
* only when a write access is performed on the AIC_IVR. Therefore, the
* Interrupt Service Routines must write (arbitrary data) to the AIC_IVR
* just after reading it. The new context of the AIC, including the value
* of the Interrupt Status Register (AIC_ISR), is updated with the current
* interrupt only when AIC_IVR is written. ..."
*
* "To summarize, in normal operating mode, the read of AIC_IVR performs the
* following operations within the AIC:
*
* 1. Calculates active interrupt (higher than current or spurious).
* 2. Determines and returns the vector of the active interrupt.
* 3. Memorizes the interrupt.
* 4. Pushes the current priority level onto the internal stack.
* 5. Acknowledges the interrupt.
*
* "However, while the Protect Mode is activated, only operations 1 to 3 are
* performed when AIC_IVR is read. Operations 4 and 5 are only performed by
* the AIC when AIC_IVR is written.
*
* "Software that has been written and debugged using the Protect Mode runs
* correctly in Normal Mode without modification. However, in Normal Mode the
* AIC_IVR write has no effect and can be removed to optimize the code.
*/
/* Write in the IVR to support Protect Mode */
regval = getreg32(SAM_AIC_IVR);
putreg32(regval, SAM_AIC_IVR);
/* Get the IRQ number from the interrrupt status register. NOTE that the
* IRQ number is the same is the peripheral ID (PID).
*/
regval = getreg32(SAM_AIC_ISR) & AIC_ISR_MASK;
/* Dispatch the interrupt */
up_doirq((int)regval, regs);
/* Acknowledge interrupt */
putreg32(AIC_EOICR_ENDIT, SAM_AIC_EOICR);
}
/****************************************************************************
* Name: up_disable_irq
*
* Description:
* Disable the IRQ specified by 'irq'
*
****************************************************************************/
void up_disable_irq(int irq)
{
irqstate_t flags;
if (irq < SAM_IRQ_NINT)
{
/* These operations must be atomic */
flags = irqsave();
/* Select the register set associated with this irq */
putreg32(irq, SAM_AIC_SSR);
/* Disable the interrupt */
putreg32(AIC_IDCR_INTD, SAM_AIC_IDCR);
sam_dumpaic("disable", irq);
irqrestore(flags);
}
#ifdef CONFIG_PIO_IRQ
else
{
/* Maybe it is a (derived) PIO IRQ */
sam_pioirqdisable(irq);
}
#endif
sam_dumpaic("disable", irq);
}
/****************************************************************************
* Name: up_enable_irq
*
* Description:
* Enable the IRQ specified by 'irq'
*
****************************************************************************/
void up_enable_irq(int irq)
{
irqstate_t flags;
if (irq < SAM_IRQ_NINT)
{
/* These operations must be atomic */
flags = irqsave();
/* Select the register set associated with this irq */
putreg32(irq, SAM_AIC_SSR);
/* Enable the interrupt */
putreg32(AIC_IECR_INTEN, SAM_AIC_IECR);
sam_dumpaic("enable", irq);
irqrestore(flags);
}
#ifdef CONFIG_PIO_IRQ
else
{
/* Maybe it is a (derived) PIO IRQ */
sam_pioirqenable(irq);
}
#endif
}
/****************************************************************************
* Name: up_maskack_irq
*
* Description:
* Mask the IRQ and acknowledge it
*
****************************************************************************/
void up_maskack_irq(int irq)
{
up_disable_irq(irq);
}
/****************************************************************************
* Name: up_prioritize_irq
*
* Description:
* Set the priority of an IRQ.
*
* Since this API is not supported on all architectures, it should be
* avoided in common implementations where possible.
*
****************************************************************************/
#ifdef CONFIG_ARCH_IRQPRIO
int up_prioritize_irq(int irq, int priority)
{
irqstate_t flags;
uint32_t regval;
DEBUGASSERT(irq < SAM_IRQ_NINT && (unsigned)priority <= AIC_SMR_PRIOR_MASK);
if (irq < SAM_IRQ_NINT)
{
/* These operations must be atomic */
flags = irqsave();
/* Select the register set associated with this irq */
putreg32(irq, SAM_AIC_SSR);
/* Unprotect and write the SMR register */
putreg32(AIC_WPMR_WPKEY, SAM_AIC_WPMR);
/* Set the new priority, preserving the current srctype */
regval = getreg32(SAM_AIC_SMR);
regval &= ~AIC_SMR_PRIOR_MASK;
regval |= (uint32_t)priority << AIC_SMR_PRIOR_SHIFT;
putreg32(regval, SAM_AIC_SMR);
/* Restore protection and the interrupt state */
putreg32(AIC_WPMR_WPKEY | AIC_WPMR_WPEN, SAM_AIC_WPMR);
sam_dumpaic("prioritize", irq);
irqrestore(flags);
}
return OK;
}
#endif
/****************************************************************************
* Name: sam_irq_srctype
*
* Description:
* irq - Identifies the IRQ source to be configured
* srctype - IRQ source configuration
*
****************************************************************************/
void sam_irq_srctype(int irq, enum sam_srctype_e srctype)
{
irqstate_t flags;
uint32_t regval;
DEBUGASSERT(irq < SAM_IRQ_NINT && (unsigned)srctype < SCRTYPE_NTYPES);
/* These operations must be atomic */
flags = irqsave();
/* Select the register set associated with this irq */
putreg32(irq, SAM_AIC_SSR);
/* Unprotect and write the SMR register */
putreg32(AIC_WPMR_WPKEY, SAM_AIC_WPMR);
/* Set the new srctype, preserving the current priority */
regval = getreg32(SAM_AIC_SMR);
regval &= ~AIC_SMR_SRCTYPE_MASK;
regval |= (uint32_t)g_srctype[srctype] << AIC_SMR_SRCTYPE_SHIFT;
putreg32(regval, SAM_AIC_SMR);
/* Restore protection and the interrupt state */
putreg32(AIC_WPMR_WPKEY | AIC_WPMR_WPEN, SAM_AIC_WPMR);
sam_dumpaic("srctype", irq);
irqrestore(flags);
}
