Add ARM GICv3 driver without support for legacy operation

This patch adds a driver for ARM GICv3 systems that need to run software
stacks where affinity routing is enabled across all privileged exception
levels for both security states. This driver is a partial implementation
of the ARM Generic Interrupt Controller Architecture Specification, GIC
architecture version 3.0 and version 4.0 (ARM IHI 0069A). The driver does
not cater for legacy support of interrupts and asymmetric configurations.

The existing GIC driver has been preserved unchanged. The common code for
GICv2 and GICv3 systems has been refactored into a new file,
`drivers/arm/gic/common/gic_common.c`. The corresponding header is in
`include/drivers/arm/gic_common.h`.

The driver interface is implemented in `drivers/arm/gic/v3/gicv3_main.c`.
The corresponding header is in `include/drivers/arm/gicv3.h`. Helper
functions are implemented in `drivers/arm/gic/v3/arm_gicv3_helpers.c`
and are accessible through the `drivers/arm/gic/v3/gicv3_private.h`
header.

Change-Id: I8c3c834a1d049d05b776b4dcb76b18ccb927444a
diff --git a/include/drivers/arm/gic_common.h b/include/drivers/arm/gic_common.h
new file mode 100644
index 0000000..6a322a2
--- /dev/null
+++ b/include/drivers/arm/gic_common.h
@@ -0,0 +1,173 @@
+/*
+ * 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.
+ */
+
+#ifndef __GIC_COMMON_H__
+#define __GIC_COMMON_H__
+
+/*******************************************************************************
+ * GIC Distributor interface general definitions
+ ******************************************************************************/
+/* Constants to categorise interrupts */
+#define MIN_SGI_ID		0
+#define MIN_PPI_ID		16
+#define MIN_SPI_ID		32
+
+/* Mask for the priority field common to all GIC interfaces */
+#define GIC_PRI_MASK			0xff
+
+/* Constant to indicate a spurious interrupt in all GIC versions */
+#define GIC_SPURIOUS_INTERRUPT		1023
+
+/* Constants to categorise priorities */
+#define GIC_HIGHEST_SEC_PRIORITY	0
+#define GIC_LOWEST_SEC_PRIORITY		127
+#define GIC_HIGHEST_NS_PRIORITY		128
+#define GIC_LOWEST_NS_PRIORITY		254 /* 255 would disable an interrupt */
+
+/*******************************************************************************
+ * GIC Distributor interface register offsets that are common to GICv3 & GICv2
+ ******************************************************************************/
+#define GICD_CTLR		0x0
+#define GICD_TYPER		0x4
+#define GICD_IIDR		0x8
+#define GICD_IGROUPR		0x80
+#define GICD_ISENABLER		0x100
+#define GICD_ICENABLER		0x180
+#define GICD_ISPENDR		0x200
+#define GICD_ICPENDR		0x280
+#define GICD_ISACTIVER		0x300
+#define GICD_ICACTIVER		0x380
+#define GICD_IPRIORITYR		0x400
+#define GICD_ICFGR		0xc00
+#define GICD_NSACR		0xe00
+
+/* GICD_CTLR bit definitions */
+#define CTLR_ENABLE_G0_SHIFT		0
+#define CTLR_ENABLE_G0_MASK		0x1
+#define CTLR_ENABLE_G0_BIT		(1 << CTLR_ENABLE_G0_SHIFT)
+
+
+/*******************************************************************************
+ * GIC Distributor interface register constants that are common to GICv3 & GICv2
+ ******************************************************************************/
+#define PIDR2_ARCH_REV_SHIFT	4
+#define PIDR2_ARCH_REV_MASK	0xf
+
+/* GICv3 revision as reported by the PIDR2 register */
+#define ARCH_REV_GICV3		0x3
+/* GICv2 revision as reported by the PIDR2 register */
+#define ARCH_REV_GICV2		0x2
+
+#define IGROUPR_SHIFT		5
+#define ISENABLER_SHIFT		5
+#define ICENABLER_SHIFT		ISENABLER_SHIFT
+#define ISPENDR_SHIFT		5
+#define ICPENDR_SHIFT		ISPENDR_SHIFT
+#define ISACTIVER_SHIFT		5
+#define ICACTIVER_SHIFT		ISACTIVER_SHIFT
+#define IPRIORITYR_SHIFT	2
+#define ICFGR_SHIFT		4
+#define NSACR_SHIFT		4
+
+/* GICD_TYPER shifts and masks */
+#define TYPER_IT_LINES_NO_SHIFT	0
+#define TYPER_IT_LINES_NO_MASK	0x1f
+
+/* Value used to initialize Normal world interrupt priorities four at a time */
+#define GICD_IPRIORITYR_DEF_VAL			\
+	(GIC_HIGHEST_NS_PRIORITY	|	\
+	(GIC_HIGHEST_NS_PRIORITY << 8)	|	\
+	(GIC_HIGHEST_NS_PRIORITY << 16)	|	\
+	(GIC_HIGHEST_NS_PRIORITY << 24))
+
+#ifndef __ASSEMBLY__
+
+#include <mmio.h>
+#include <stdint.h>
+
+/*******************************************************************************
+ * GIC Distributor interface register accessors that are common to GICv3 & GICv2
+ ******************************************************************************/
+static inline unsigned int gicd_read_ctlr(uintptr_t base)
+{
+	return mmio_read_32(base + GICD_CTLR);
+}
+
+static inline unsigned int gicd_read_typer(uintptr_t base)
+{
+	return mmio_read_32(base + GICD_TYPER);
+}
+
+static inline unsigned int gicd_read_iidr(uintptr_t base)
+{
+	return mmio_read_32(base + GICD_IIDR);
+}
+
+static inline void gicd_write_ctlr(uintptr_t base, unsigned int val)
+{
+	mmio_write_32(base + GICD_CTLR, val);
+}
+
+/*******************************************************************************
+ * GIC Distributor function prototypes
+ ******************************************************************************/
+unsigned int gicd_read_igroupr(uintptr_t base, unsigned int id);
+unsigned int gicd_read_isenabler(uintptr_t base, unsigned int id);
+unsigned int gicd_read_icenabler(uintptr_t base, unsigned int id);
+unsigned int gicd_read_ispendr(uintptr_t base, unsigned int id);
+unsigned int gicd_read_icpendr(uintptr_t base, unsigned int id);
+unsigned int gicd_read_isactiver(uintptr_t base, unsigned int id);
+unsigned int gicd_read_icactiver(uintptr_t base, unsigned int id);
+unsigned int gicd_read_ipriorityr(uintptr_t base, unsigned int id);
+unsigned int gicd_read_icfgr(uintptr_t base, unsigned int id);
+unsigned int gicd_read_nsacr(uintptr_t base, unsigned int id);
+void gicd_write_igroupr(uintptr_t base, unsigned int id, unsigned int val);
+void gicd_write_isenabler(uintptr_t base, unsigned int id, unsigned int val);
+void gicd_write_icenabler(uintptr_t base, unsigned int id, unsigned int val);
+void gicd_write_ispendr(uintptr_t base, unsigned int id, unsigned int val);
+void gicd_write_icpendr(uintptr_t base, unsigned int id, unsigned int val);
+void gicd_write_isactiver(uintptr_t base, unsigned int id, unsigned int val);
+void gicd_write_icactiver(uintptr_t base, unsigned int id, unsigned int val);
+void gicd_write_ipriorityr(uintptr_t base, unsigned int id, unsigned int val);
+void gicd_write_icfgr(uintptr_t base, unsigned int id, unsigned int val);
+void gicd_write_nsacr(uintptr_t base, unsigned int id, unsigned int val);
+unsigned int gicd_get_igroupr(uintptr_t base, unsigned int id);
+void gicd_set_igroupr(uintptr_t base, unsigned int id);
+void gicd_clr_igroupr(uintptr_t base, unsigned int id);
+void gicd_set_isenabler(uintptr_t base, unsigned int id);
+void gicd_set_icenabler(uintptr_t base, unsigned int id);
+void gicd_set_ispendr(uintptr_t base, unsigned int id);
+void gicd_set_icpendr(uintptr_t base, unsigned int id);
+void gicd_set_isactiver(uintptr_t base, unsigned int id);
+void gicd_set_icactiver(uintptr_t base, unsigned int id);
+
+
+#endif /* __ASSEMBLY__ */
+#endif /* __GIC_COMMON_H__ */