AArch32: Add support in TF libraries

This patch adds AArch32 support to cpu ops, context management,
per-cpu data and spinlock libraries. The `entrypoint_info`
structure is modified to add support for AArch32 register
arguments. The CPU operations for AEM generic cpu in AArch32
mode is also added.

Change-Id: I1e52e79f498661d8f31f1e7b3a29e222bc7a4483
diff --git a/lib/cpus/aarch32/aem_generic.S b/lib/cpus/aarch32/aem_generic.S
new file mode 100644
index 0000000..10ea4e4
--- /dev/null
+++ b/lib/cpus/aarch32/aem_generic.S
@@ -0,0 +1,68 @@
+/*
+ * Copyright (c) 2016, 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 <aem_generic.h>
+#include <arch.h>
+#include <asm_macros.S>
+#include <assert_macros.S>
+#include <cpu_macros.S>
+
+func aem_generic_core_pwr_dwn
+	/* Assert if cache is enabled */
+#if ASM_ASSERTION
+	ldcopr	r0, SCTLR
+	tst	r0, #SCTLR_C_BIT
+	ASM_ASSERT(eq)
+#endif
+	/* ---------------------------------------------
+	 * Flush L1 cache to PoU.
+	 * ---------------------------------------------
+	 */
+	mov	r0, #DC_OP_CISW
+	b	dcsw_op_louis
+endfunc aem_generic_core_pwr_dwn
+
+
+func aem_generic_cluster_pwr_dwn
+	/* Assert if cache is enabled */
+#if ASM_ASSERTION
+	ldcopr	r0, SCTLR
+	tst	r0, #SCTLR_C_BIT
+	ASM_ASSERT(eq)
+#endif
+	/* ---------------------------------------------
+	 * Flush L1 and L2 caches to PoC.
+	 * ---------------------------------------------
+	 */
+	mov	r0, #DC_OP_CISW
+	b	dcsw_op_all
+endfunc aem_generic_cluster_pwr_dwn
+
+/* cpu_ops for Base AEM FVP */
+declare_cpu_ops aem_generic, BASE_AEM_MIDR, 1
diff --git a/lib/cpus/aarch32/cpu_helpers.S b/lib/cpus/aarch32/cpu_helpers.S
new file mode 100644
index 0000000..927a6f5
--- /dev/null
+++ b/lib/cpus/aarch32/cpu_helpers.S
@@ -0,0 +1,177 @@
+/*
+ * Copyright (c) 2016, 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 <asm_macros.S>
+#include <assert_macros.S>
+#include <cpu_data.h>
+#include <cpu_macros.S>
+
+	/*
+	 * The reset handler common to all platforms.  After a matching
+	 * cpu_ops structure entry is found, the correponding reset_handler
+	 * in the cpu_ops is invoked. The reset handler is invoked very early
+	 * in the boot sequence and it is assumed that we can clobber r0 - r10
+	 * without the need to follow AAPCS.
+	 * Clobbers: r0 - r10
+	 */
+	.globl	reset_handler
+func reset_handler
+	mov	r10, lr
+
+	/* The plat_reset_handler can clobber r0 - r9 */
+	bl	plat_reset_handler
+
+	/* Get the matching cpu_ops pointer (clobbers: r0 - r5) */
+	bl	get_cpu_ops_ptr
+
+#if ASM_ASSERTION
+	cmp	r0, #0
+	ASM_ASSERT(ne)
+#endif
+
+	/* Get the cpu_ops reset handler */
+	ldr	r1, [r0, #CPU_RESET_FUNC]
+	cmp	r1, #0
+	mov	lr, r10
+	bxne	r1
+	bx	lr
+endfunc reset_handler
+
+	/*
+	 * The prepare core power down function for all platforms.  After
+	 * the cpu_ops pointer is retrieved from cpu_data, the corresponding
+	 * pwr_dwn_core in the cpu_ops is invoked. Follows AAPCS.
+	 */
+	.globl	prepare_core_pwr_dwn
+func prepare_core_pwr_dwn
+	push	{lr}
+	bl	_cpu_data
+	pop	{lr}
+
+	ldr	r1, [r0, #CPU_DATA_CPU_OPS_PTR]
+#if ASM_ASSERTION
+	cmp	r1, #0
+	ASM_ASSERT(ne)
+#endif
+
+	/* Get the cpu_ops core_pwr_dwn handler */
+	ldr	r0, [r1, #CPU_PWR_DWN_CORE]
+	bx	r0
+endfunc prepare_core_pwr_dwn
+
+	/*
+	 * The prepare cluster power down function for all platforms.  After
+	 * the cpu_ops pointer is retrieved from cpu_data, the corresponding
+	 * pwr_dwn_cluster in the cpu_ops is invoked. Follows AAPCS.
+	 */
+	.globl	prepare_cluster_pwr_dwn
+func prepare_cluster_pwr_dwn
+	push	{lr}
+	bl	_cpu_data
+	pop	{lr}
+
+	ldr	r1, [r0, #CPU_DATA_CPU_OPS_PTR]
+#if ASM_ASSERTION
+	cmp	r1, #0
+	ASM_ASSERT(ne)
+#endif
+
+	/* Get the cpu_ops cluster_pwr_dwn handler */
+	ldr	r0, [r1, #CPU_PWR_DWN_CLUSTER]
+	bx	r0
+endfunc prepare_cluster_pwr_dwn
+
+	/*
+	 * Initializes the cpu_ops_ptr if not already initialized
+	 * in cpu_data. This must only be called after the data cache
+	 * is enabled. AAPCS is followed.
+	 */
+	.globl	init_cpu_ops
+func init_cpu_ops
+	push	{r4 - r6, lr}
+	bl	_cpu_data
+	mov	r6, r0
+	ldr	r1, [r0, #CPU_DATA_CPU_OPS_PTR]
+	cmp	r1, #0
+	bne	1f
+	bl	get_cpu_ops_ptr
+#if ASM_ASSERTION
+	cmp	r0, #0
+	ASM_ASSERT(ne)
+#endif
+	str	r0, [r6, #CPU_DATA_CPU_OPS_PTR]!
+1:
+	pop	{r4 - r6, pc}
+endfunc init_cpu_ops
+
+	/*
+	 * The below function returns the cpu_ops structure matching the
+	 * midr of the core. It reads the MIDR and finds the matching
+	 * entry in cpu_ops entries. Only the implementation and part number
+	 * are used to match the entries.
+	 * Return :
+	 *     r0 - The matching cpu_ops pointer on Success
+	 *     r0 - 0 on failure.
+	 * Clobbers: r0 - r5
+	 */
+	.globl	get_cpu_ops_ptr
+func get_cpu_ops_ptr
+	/* Get the cpu_ops start and end locations */
+	ldr	r4, =(__CPU_OPS_START__ + CPU_MIDR)
+	ldr	r5, =(__CPU_OPS_END__ + CPU_MIDR)
+
+	/* Initialize the return parameter */
+	mov	r0, #0
+
+	/* Read the MIDR_EL1 */
+	ldcopr	r2, MIDR
+	ldr	r3, =CPU_IMPL_PN_MASK
+
+	/* Retain only the implementation and part number using mask */
+	and	r2, r2, r3
+1:
+	/* Check if we have reached end of list */
+	cmp	r4, r5
+	bge	error_exit
+
+	/* load the midr from the cpu_ops */
+	ldr	r1, [r4], #CPU_OPS_SIZE
+	and	r1, r1, r3
+
+	/* Check if midr matches to midr of this core */
+	cmp	r1, r2
+	bne	1b
+
+	/* Subtract the increment and offset to get the cpu-ops pointer */
+	sub	r0, r4, #(CPU_OPS_SIZE + CPU_MIDR)
+error_exit:
+	bx	lr
+endfunc get_cpu_ops_ptr