• Achin Gupta's avatar
    Introduce interrupt registration framework in BL3-1 · 126747f7
    Achin Gupta authored
    This patch introduces a framework for registering interrupts routed to
    EL3. The interrupt routing model is governed by the SCR_EL3.IRQ and
    FIQ bits and the security state an interrupt is generated in. The
    framework recognizes three type of interrupts depending upon which
    exception level and security state they should be handled in
    i.e. Secure EL1 interrupts, Non-secure interrupts and EL3
    interrupts. It provides an API and macros that allow a runtime service
    to register an handler for a type of interrupt and specify the routing
    model. The framework validates the routing model and uses the context
    management framework to ensure that it is applied to the SCR_EL3 prior
    to entry into the target security state. It saves the handler in
    internal data structures. An API is provided to retrieve the handler
    when an interrupt of a particular type is asserted. Registration is
    expected to be done once by the primary CPU. The same handler and
    routing model is used for all CPUs.
    
    Support for EL3 interrupts will be added to the framework in the
    future. A makefile flag has been added to allow the FVP port choose
    between ARM GIC v2 and v3 support in EL3. The latter version is
    currently unsupported.
    
    A framework for handling interrupts in BL3-1 will be introduced in
    subsequent patches. The default routing model in the absence of any
    handlers expects no interrupts to be routed to EL3.
    
    Change-Id: Idf7c023b34fcd4800a5980f2bef85e4b5c29e649
    126747f7
gic_v2.c 10 KB
/*
 * Copyright (c) 2013-2014, ARM Limited and Contributors. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * 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.
 *
 * Neither the name of ARM 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 HOLDER 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.
 */

#include <arch.h>
#include <assert.h>
#include <gic_v2.h>
#include <interrupt_mgmt.h>
#include <mmio.h>

/*******************************************************************************
 * GIC Distributor interface accessors for reading entire registers
 ******************************************************************************/

unsigned int gicd_read_igroupr(unsigned int base, unsigned int id)
{
	unsigned n = id >> IGROUPR_SHIFT;
	return mmio_read_32(base + GICD_IGROUPR + (n << 2));
}

unsigned int gicd_read_isenabler(unsigned int base, unsigned int id)
{
	unsigned n = id >> ISENABLER_SHIFT;
	return mmio_read_32(base + GICD_ISENABLER + (n << 2));
}

unsigned int gicd_read_icenabler(unsigned int base, unsigned int id)
{
	unsigned n = id >> ICENABLER_SHIFT;
	return mmio_read_32(base + GICD_ICENABLER + (n << 2));
}

unsigned int gicd_read_ispendr(unsigned int base, unsigned int id)
{
	unsigned n = id >> ISPENDR_SHIFT;
	return mmio_read_32(base + GICD_ISPENDR + (n << 2));
}

unsigned int gicd_read_icpendr(unsigned int base, unsigned int id)
{
	unsigned n = id >> ICPENDR_SHIFT;
	return mmio_read_32(base + GICD_ICPENDR + (n << 2));
}

unsigned int gicd_read_isactiver(unsigned int base, unsigned int id)
{
	unsigned n = id >> ISACTIVER_SHIFT;
	return mmio_read_32(base + GICD_ISACTIVER + (n << 2));
}

unsigned int gicd_read_icactiver(unsigned int base, unsigned int id)
{
	unsigned n = id >> ICACTIVER_SHIFT;
	return mmio_read_32(base + GICD_ICACTIVER + (n << 2));
}

unsigned int gicd_read_ipriorityr(unsigned int base, unsigned int id)
{
	unsigned n = id >> IPRIORITYR_SHIFT;
	return mmio_read_32(base + GICD_IPRIORITYR + (n << 2));
}

unsigned int gicd_read_itargetsr(unsigned int base, unsigned int id)
{
	unsigned n = id >> ITARGETSR_SHIFT;
	return mmio_read_32(base + GICD_ITARGETSR + (n << 2));
}

unsigned int gicd_read_icfgr(unsigned int base, unsigned int id)
{
	unsigned n = id >> ICFGR_SHIFT;
	return mmio_read_32(base + GICD_ICFGR + (n << 2));
}

unsigned int gicd_read_cpendsgir(unsigned int base, unsigned int id)
{
	unsigned n = id >> CPENDSGIR_SHIFT;
	return mmio_read_32(base + GICD_CPENDSGIR + (n << 2));
}

unsigned int gicd_read_spendsgir(unsigned int base, unsigned int id)
{
	unsigned n = id >> SPENDSGIR_SHIFT;
	return mmio_read_32(base + GICD_SPENDSGIR + (n << 2));
}

/*******************************************************************************
 * GIC Distributor interface accessors for writing entire registers
 ******************************************************************************/

void gicd_write_igroupr(unsigned int base, unsigned int id, unsigned int val)
{
	unsigned n = id >> IGROUPR_SHIFT;
	mmio_write_32(base + GICD_IGROUPR + (n << 2), val);
}

void gicd_write_isenabler(unsigned int base, unsigned int id, unsigned int val)
{
	unsigned n = id >> ISENABLER_SHIFT;
	mmio_write_32(base + GICD_ISENABLER + (n << 2), val);
}

void gicd_write_icenabler(unsigned int base, unsigned int id, unsigned int val)
{
	unsigned n = id >> ICENABLER_SHIFT;
	mmio_write_32(base + GICD_ICENABLER + (n << 2), val);
}

void gicd_write_ispendr(unsigned int base, unsigned int id, unsigned int val)
{
	unsigned n = id >> ISPENDR_SHIFT;
	mmio_write_32(base + GICD_ISPENDR + (n << 2), val);
}

void gicd_write_icpendr(unsigned int base, unsigned int id, unsigned int val)
{
	unsigned n = id >> ICPENDR_SHIFT;
	mmio_write_32(base + GICD_ICPENDR + (n << 2), val);
}

void gicd_write_isactiver(unsigned int base, unsigned int id, unsigned int val)
{
	unsigned n = id >> ISACTIVER_SHIFT;
	mmio_write_32(base + GICD_ISACTIVER + (n << 2), val);
}

void gicd_write_icactiver(unsigned int base, unsigned int id, unsigned int val)
{
	unsigned n = id >> ICACTIVER_SHIFT;
	mmio_write_32(base + GICD_ICACTIVER + (n << 2), val);
}

void gicd_write_ipriorityr(unsigned int base, unsigned int id, unsigned int val)
{
	unsigned n = id >> IPRIORITYR_SHIFT;
	mmio_write_32(base + GICD_IPRIORITYR + (n << 2), val);
}

void gicd_write_itargetsr(unsigned int base, unsigned int id, unsigned int val)
{
	unsigned n = id >> ITARGETSR_SHIFT;
	mmio_write_32(base + GICD_ITARGETSR + (n << 2), val);
}

void gicd_write_icfgr(unsigned int base, unsigned int id, unsigned int val)
{
	unsigned n = id >> ICFGR_SHIFT;
	mmio_write_32(base + GICD_ICFGR + (n << 2), val);
}

void gicd_write_cpendsgir(unsigned int base, unsigned int id, unsigned int val)
{
	unsigned n = id >> CPENDSGIR_SHIFT;
	mmio_write_32(base + GICD_CPENDSGIR + (n << 2), val);
}

void gicd_write_spendsgir(unsigned int base, unsigned int id, unsigned int val)
{
	unsigned n = id >> SPENDSGIR_SHIFT;
	mmio_write_32(base + GICD_SPENDSGIR + (n << 2), val);
}

/*******************************************************************************
 * GIC Distributor interface accessors for individual interrupt manipulation
 ******************************************************************************/
unsigned int gicd_get_igroupr(unsigned int base, unsigned int id)
{
	unsigned bit_num = id & ((1 << IGROUPR_SHIFT) - 1);
	unsigned int reg_val = gicd_read_igroupr(base, id);

	return (reg_val >> bit_num) & 0x1;
}

void gicd_set_igroupr(unsigned int base, unsigned int id)
{
	unsigned bit_num = id & ((1 << IGROUPR_SHIFT) - 1);
	unsigned int reg_val = gicd_read_igroupr(base, id);

	gicd_write_igroupr(base, id, reg_val | (1 << bit_num));
}

void gicd_clr_igroupr(unsigned int base, unsigned int id)
{
	unsigned bit_num = id & ((1 << IGROUPR_SHIFT) - 1);
	unsigned int reg_val = gicd_read_igroupr(base, id);

	gicd_write_igroupr(base, id, reg_val & ~(1 << bit_num));
}

void gicd_set_isenabler(unsigned int base, unsigned int id)
{
	unsigned bit_num = id & ((1 << ISENABLER_SHIFT) - 1);

	gicd_write_isenabler(base, id, (1 << bit_num));
}

void gicd_set_icenabler(unsigned int base, unsigned int id)
{
	unsigned bit_num = id & ((1 << ICENABLER_SHIFT) - 1);

	gicd_write_icenabler(base, id, (1 << bit_num));
}

void gicd_set_ispendr(unsigned int base, unsigned int id)
{
	unsigned bit_num = id & ((1 << ISPENDR_SHIFT) - 1);

	gicd_write_ispendr(base, id, (1 << bit_num));
}

void gicd_set_icpendr(unsigned int base, unsigned int id)
{
	unsigned bit_num = id & ((1 << ICPENDR_SHIFT) - 1);

	gicd_write_icpendr(base, id, (1 << bit_num));
}

void gicd_set_isactiver(unsigned int base, unsigned int id)
{
	unsigned bit_num = id & ((1 << ISACTIVER_SHIFT) - 1);

	gicd_write_isactiver(base, id, (1 << bit_num));
}

void gicd_set_icactiver(unsigned int base, unsigned int id)
{
	unsigned bit_num = id & ((1 << ICACTIVER_SHIFT) - 1);

	gicd_write_icactiver(base, id, (1 << bit_num));
}

/*
 * Make sure that the interrupt's group is set before expecting
 * this function to do its job correctly.
 */
void gicd_set_ipriorityr(unsigned int base, unsigned int id, unsigned int pri)
{
	unsigned int reg = base + GICD_IPRIORITYR + (id & ~3);
	unsigned int shift = (id & 3) << 3;
	unsigned int reg_val = mmio_read_32(reg);

	/*
	 * Enforce ARM recommendation to manage priority values such
	 * that group1 interrupts always have a lower priority than
	 * group0 interrupts.
	 * Note, lower numerical values are higher priorities so the comparison
	 * checks below are reversed from what might be expected.
	 */
	assert(gicd_get_igroupr(base, id) == GRP1 ?
		pri >= GIC_HIGHEST_NS_PRIORITY &&
			pri <= GIC_LOWEST_NS_PRIORITY :
		pri >= GIC_HIGHEST_SEC_PRIORITY &&
			pri <= GIC_LOWEST_SEC_PRIORITY);

	reg_val &= ~(GIC_PRI_MASK << shift);
	reg_val |= (pri & GIC_PRI_MASK) << shift;
	mmio_write_32(reg, reg_val);
}

void gicd_set_itargetsr(unsigned int base, unsigned int id, unsigned int iface)
{
	unsigned byte_off = id & ((1 << ITARGETSR_SHIFT) - 1);
	unsigned int reg_val = gicd_read_itargetsr(base, id);

	gicd_write_itargetsr(base, id, reg_val |
			     (1 << iface) << (byte_off << 3));
}

/*******************************************************************************
 * This function allows the interrupt management framework to determine (through
 * the platform) which interrupt line (IRQ/FIQ) to use for an interrupt type to
 * route it to EL3. The interrupt line is represented as the bit position of the
 * IRQ or FIQ bit in the SCR_EL3.
 ******************************************************************************/
uint32_t gicv2_interrupt_type_to_line(uint32_t cpuif_base, uint32_t type)
{
	uint32_t gicc_ctlr;

	/* Non-secure interrupts are signalled on the IRQ line always */
	if (type == INTR_TYPE_NS)
		return __builtin_ctz(SCR_IRQ_BIT);

	/*
	 * Secure interrupts are signalled using the IRQ line if the FIQ_EN
	 * bit is not set else they are signalled using the FIQ line.
	 */
	gicc_ctlr = gicc_read_ctlr(cpuif_base);
	if (gicc_ctlr & FIQ_EN)
		return __builtin_ctz(SCR_FIQ_BIT);
	else
		return __builtin_ctz(SCR_IRQ_BIT);
}