Per-cpu data cache restructuring

This patch prepares the per-cpu pointer cache for wider use by:
* renaming the structure to cpu_data and placing in new header
* providing accessors for this CPU, or other CPUs
* splitting the initialization of the TPIDR pointer from the
  initialization of the cpu_data content
* moving the crash stack initialization to a crash stack function
* setting the TPIDR pointer very early during boot

Change-Id: Icef9004ff88f8eb241d48c14be3158087d7e49a3
diff --git a/include/bl31/context.h b/include/bl31/context.h
index 16cc744..b889f68 100644
--- a/include/bl31/context.h
+++ b/include/bl31/context.h
@@ -185,11 +185,6 @@
 #define CTX_FP_FPCR		0x208
 #define CTX_FPREGS_END		0x210
 
-/******************************************************************************
- * Offsets for the per cpu cache implementation
- ******************************************************************************/
-#define PTR_CACHE_CRASH_STACK_OFFSET 0x0
-
 #ifndef __ASSEMBLY__
 
 #include <cassert.h>
@@ -331,17 +326,6 @@
 void fpregs_context_restore(fp_regs_t *regs);
 
 
-/* Per-CPU pointer cache of recently used pointers and also the crash stack
- * TODO: Add other commonly used variables to this (tf_issues#90)
- */
-typedef struct per_cpu_ptr_cache {
-	uint64_t crash_stack;
-} per_cpu_ptr_cache_t;
-
-CASSERT(PTR_CACHE_CRASH_STACK_OFFSET == __builtin_offsetof\
-	(per_cpu_ptr_cache_t, crash_stack), \
-	assert_per_cpu_ptr_cache_crash_stack_offset_mismatch);
-
 #undef CTX_SYSREG_ALL
 #undef CTX_FP_ALL
 #undef CTX_GPREG_ALL
diff --git a/include/bl31/context_mgmt.h b/include/bl31/context_mgmt.h
index 86bbc58..ca9d9fa 100644
--- a/include/bl31/context_mgmt.h
+++ b/include/bl31/context_mgmt.h
@@ -54,8 +54,6 @@
 			  uint32_t bit_pos,
 			  uint32_t value);
 void cm_set_next_eret_context(uint32_t security_state);
-void cm_init_pcpu_ptr_cache();
-void cm_set_pcpu_ptr_cache(const void *pcpu_ptr);
-void *cm_get_pcpu_ptr_cache(void);
 uint32_t cm_get_scr_el3(uint32_t security_state);
+
 #endif /* __CM_H__ */
diff --git a/include/bl31/cpu_data.h b/include/bl31/cpu_data.h
new file mode 100644
index 0000000..2d256e4
--- /dev/null
+++ b/include/bl31/cpu_data.h
@@ -0,0 +1,90 @@
+/*
+ * Copyright (c) 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.
+ */
+
+#ifndef __CPU_DATA_H__
+#define __CPU_DATA_H__
+
+/* Offsets for the cpu_data structure */
+#define CPU_DATA_CRASH_STACK_OFFSET	0x0
+#define CPU_DATA_LOG2SIZE		6
+
+#ifndef __ASSEMBLY__
+
+#include <arch_helpers.h>
+#include <platform_def.h>
+#include <stdint.h>
+
+/*******************************************************************************
+ * Function & variable prototypes
+ ******************************************************************************/
+
+/*******************************************************************************
+ * Cache of frequently used per-cpu data:
+ *   Address of the crash stack
+ * It is aligned to the cache line boundary to allow efficient concurrent
+ * manipulation of these pointers on different cpus
+ *
+ * TODO: Add other commonly used variables to this (tf_issues#90)
+ *
+ * The data structure and the _cpu_data accessors should not be used directly
+ * by components that have per-cpu members. The member access macros should be
+ * used for this.
+ ******************************************************************************/
+
+typedef struct cpu_data {
+	uint64_t crash_stack;
+} __aligned(CACHE_WRITEBACK_GRANULE) cpu_data_t;
+
+struct cpu_data *_cpu_data_by_index(uint32_t cpu_index);
+struct cpu_data *_cpu_data_by_mpidr(uint64_t mpidr);
+
+/* Return the cpu_data structure for the current CPU. */
+static inline struct cpu_data *_cpu_data(void)
+{
+	return (cpu_data_t *)read_tpidr_el3();
+}
+
+
+/**************************************************************************
+ * APIs for initialising and accessing per-cpu data
+ *************************************************************************/
+
+void init_cpu_data_ptr(void);
+
+#define get_cpu_data(_m)		   _cpu_data()->_m
+#define set_cpu_data(_m, _v)		   _cpu_data()->_m = _v
+#define get_cpu_data_by_index(_ix, _m)	   _cpu_data_by_index(_ix)->_m
+#define set_cpu_data_by_index(_ix, _m, _v) _cpu_data_by_index(_ix)->_m = _v
+#define get_cpu_data_by_mpidr(_id, _m)	   _cpu_data_by_mpidr(_id)->_m
+#define set_cpu_data_by_mpidr(_id, _m, _v) _cpu_data_by_mpidr(_id)->_m = _v
+
+
+#endif /* __ASSEMBLY__ */
+#endif /* __CPU_DATA_H__ */
diff --git a/include/bl31/runtime_svc.h b/include/bl31/runtime_svc.h
index d7d88d4..3b84f06 100644
--- a/include/bl31/runtime_svc.h
+++ b/include/bl31/runtime_svc.h
@@ -267,7 +267,8 @@
 void runtime_svc_init();
 extern uint64_t __RT_SVC_DESCS_START__;
 extern uint64_t __RT_SVC_DESCS_END__;
-uint64_t get_crash_stack(uint64_t mpidr);
+void init_crash_reporting(void);
 void runtime_exceptions(void);
+
 #endif /*__ASSEMBLY__*/
 #endif /* __RUNTIME_SVC_H__ */