Add ARM GICv2 driver

This patch adds a driver for ARM GICv2 systems, example GIC-400. Unlike
the existing GIC driver in `include/drivers/arm/arm_gic.h`, this driver
is optimised for GICv2 and does not support GICv3 systems in GICv2
compatibility mode. The driver interface has been implemented in
`drivers/arm/gic/v2/gicv2_main.c`. The corresponding header is in
`include/drivers/arm/gicv2.h`. Helper functions are implemented in
`drivers/arm/gic/v2/gicv2_helpers.c` and are accessible through the
`drivers/arm/gic/v2/gicv2_private.h` header.

Change-Id: I09fffa4e621fb99ba3c01204839894816cd89a2a

1 files changed, 254 insertions, 0 deletions

diff --git a/drivers/arm/gic/v2/gicv2_main.c b/drivers/arm/gic/v2/gicv2_main.c
new file mode 100644
index 00000000..cf939261
--- /dev/null
+++ b/drivers/arm/gic/v2/gicv2_main.c
@@ -0,0 +1,254 @@
+/*
+ * Copyright (c) 2015, 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 <arch_helpers.h>
+#include <assert.h>
+#include <debug.h>
+#include <gic_common.h>
+#include <gicv2.h>
+#include "gicv2_private.h"
+
+static const gicv2_driver_data_t *driver_data;
+
+/*******************************************************************************
+ * Enable secure interrupts and use FIQs to route them. Disable legacy bypass
+ * and set the priority mask register to allow all interrupts to trickle in.
+ ******************************************************************************/
+void gicv2_cpuif_enable(void)
+{
+	unsigned int val;
+
+	assert(driver_data);
+	assert(driver_data->gicc_base);
+
+	/*
+	 * Enable the Group 0 interrupts, FIQEn and disable Group 0/1
+	 * bypass.
+	 */
+	val = CTLR_ENABLE_G0_BIT | FIQ_EN_BIT | FIQ_BYP_DIS_GRP0;
+	val |= IRQ_BYP_DIS_GRP0 | FIQ_BYP_DIS_GRP1 | IRQ_BYP_DIS_GRP1;
+
+	/* Program the idle priority in the PMR */
+	gicc_write_pmr(driver_data->gicc_base, GIC_PRI_MASK);
+	gicc_write_ctlr(driver_data->gicc_base, val);
+}
+
+/*******************************************************************************
+ * Place the cpu interface in a state where it can never make a cpu exit wfi as
+ * as result of an asserted interrupt. This is critical for powering down a cpu
+ ******************************************************************************/
+void gicv2_cpuif_disable(void)
+{
+	unsigned int val;
+
+	assert(driver_data);
+	assert(driver_data->gicc_base);
+
+	/* Disable secure, non-secure interrupts and disable their bypass */
+	val = gicc_read_ctlr(driver_data->gicc_base);
+	val &= ~(CTLR_ENABLE_G0_BIT | CTLR_ENABLE_G1_BIT);
+	val |= FIQ_BYP_DIS_GRP1 | FIQ_BYP_DIS_GRP0;
+	val |= IRQ_BYP_DIS_GRP0 | IRQ_BYP_DIS_GRP1;
+	gicc_write_ctlr(driver_data->gicc_base, val);
+}
+
+/*******************************************************************************
+ * Per cpu gic distributor setup which will be done by all cpus after a cold
+ * boot/hotplug. This marks out the secure SPIs and PPIs & enables them.
+ ******************************************************************************/
+void gicv2_pcpu_distif_init(void)
+{
+	assert(driver_data);
+	assert(driver_data->gicd_base);
+	assert(driver_data->g0_interrupt_array);
+
+	gicv2_secure_ppi_sgi_setup(driver_data->gicd_base,
+					driver_data->g0_interrupt_num,
+					driver_data->g0_interrupt_array);
+}
+
+/*******************************************************************************
+ * Global gic distributor init which will be done by the primary cpu after a
+ * cold boot. It marks out the secure SPIs, PPIs & SGIs and enables them. It
+ * then enables the secure GIC distributor interface.
+ ******************************************************************************/
+void gicv2_distif_init(void)
+{
+	unsigned int ctlr;
+
+	assert(driver_data);
+	assert(driver_data->gicd_base);
+	assert(driver_data->g0_interrupt_array);
+
+	/* Disable the distributor before going further */
+	ctlr = gicd_read_ctlr(driver_data->gicd_base);
+	gicd_write_ctlr(driver_data->gicd_base,
+			ctlr & ~(CTLR_ENABLE_G0_BIT | CTLR_ENABLE_G1_BIT));
+
+	/* Set the default attribute of all SPIs */
+	gicv2_spis_configure_defaults(driver_data->gicd_base);
+
+	/* Configure the G0 SPIs */
+	gicv2_secure_spis_configure(driver_data->gicd_base,
+					driver_data->g0_interrupt_num,
+					driver_data->g0_interrupt_array);
+
+	/* Re-enable the secure SPIs now that they have been configured */
+	gicd_write_ctlr(driver_data->gicd_base, ctlr | CTLR_ENABLE_G0_BIT);
+}
+
+/*******************************************************************************
+ * Initialize the ARM GICv2 driver with the provided platform inputs
+ ******************************************************************************/
+void gicv2_driver_init(const gicv2_driver_data_t *plat_driver_data)
+{
+	unsigned int gic_version;
+	assert(plat_driver_data);
+	assert(plat_driver_data->gicd_base);
+	assert(plat_driver_data->gicc_base);
+
+	/*
+	 * The platform should provide a list of atleast one type of
+	 * interrupts
+	 */
+	assert(plat_driver_data->g0_interrupt_array);
+
+	/*
+	 * If there are no interrupts of a particular type, then the number of
+	 * interrupts of that type should be 0 and vice-versa.
+	 */
+	assert(plat_driver_data->g0_interrupt_array ?
+	       plat_driver_data->g0_interrupt_num :
+	       plat_driver_data->g0_interrupt_num == 0);
+
+	/* Ensure that this is a GICv2 system */
+	gic_version = gicd_read_pidr2(plat_driver_data->gicd_base);
+	gic_version = (gic_version >> PIDR2_ARCH_REV_SHIFT)
+					& PIDR2_ARCH_REV_MASK;
+	assert(gic_version == ARCH_REV_GICV2);
+
+	driver_data = plat_driver_data;
+
+	INFO("ARM GICv2 driver initialized\n");
+}
+
+/******************************************************************************
+ * This function returns whether FIQ is enabled in the GIC CPU interface.
+ *****************************************************************************/
+unsigned int gicv2_is_fiq_enabled(void)
+{
+	unsigned int gicc_ctlr;
+
+	assert(driver_data);
+	assert(driver_data->gicc_base);
+
+	gicc_ctlr = gicc_read_ctlr(driver_data->gicc_base);
+	return (gicc_ctlr >> FIQ_EN_SHIFT) & 0x1;
+}
+
+/*******************************************************************************
+ * This function returns the type of the highest priority pending interrupt at
+ * the GIC cpu interface. The return values can be one of the following :
+ *   PENDING_G1_INTID   : The interrupt type is non secure Group 1.
+ *   0 - 1019           : The interrupt type is secure Group 0.
+ *   GIC_SPURIOUS_INTERRUPT : there is no pending interrupt with
+ *                            sufficient priority to be signaled
+ ******************************************************************************/
+unsigned int gicv2_get_pending_interrupt_type(void)
+{
+	assert(driver_data);
+	assert(driver_data->gicc_base);
+
+	return gicc_read_hppir(driver_data->gicc_base) & INT_ID_MASK;
+}
+
+/*******************************************************************************
+ * This function returns the id of the highest priority pending interrupt at
+ * the GIC cpu interface. GIC_SPURIOUS_INTERRUPT is returned when there is no
+ * interrupt pending.
+ ******************************************************************************/
+unsigned int gicv2_get_pending_interrupt_id(void)
+{
+	unsigned int id;
+
+	assert(driver_data);
+	assert(driver_data->gicc_base);
+
+	id = gicc_read_hppir(driver_data->gicc_base) & INT_ID_MASK;
+
+	/*
+	 * Find out which non-secure interrupt it is under the assumption that
+	 * the GICC_CTLR.AckCtl bit is 0.
+	 */
+	if (id == PENDING_G1_INTID)
+		id = gicc_read_ahppir(driver_data->gicc_base) & INT_ID_MASK;
+
+	return id;
+}
+
+/*******************************************************************************
+ * This functions reads the GIC cpu interface Interrupt Acknowledge register
+ * to start handling the pending secure 0 interrupt. It returns the
+ * contents of the IAR.
+ ******************************************************************************/
+unsigned int gicv2_acknowledge_interrupt(void)
+{
+	assert(driver_data);
+	assert(driver_data->gicc_base);
+
+	return gicc_read_IAR(driver_data->gicc_base);
+}
+
+/*******************************************************************************
+ * This functions writes the GIC cpu interface End Of Interrupt register with
+ * the passed value to finish handling the active secure group 0 interrupt.
+ ******************************************************************************/
+void gicv2_end_of_interrupt(unsigned int id)
+{
+	assert(driver_data);
+	assert(driver_data->gicc_base);
+
+	gicc_write_EOIR(driver_data->gicc_base, id);
+}
+
+/*******************************************************************************
+ * This function returns the type of the interrupt id depending upon the group
+ * this interrupt has been configured under by the interrupt controller i.e.
+ * group0 secure or group1 non secure. It returns zero for Group 0 secure and
+ * one for Group 1 non secure interrupt.
+ ******************************************************************************/
+unsigned int gicv2_get_interrupt_group(unsigned int id)
+{
+	assert(driver_data);
+	assert(driver_data->gicd_base);
+
+	return gicd_get_igroupr(driver_data->gicd_base, id);
+}