/*
 * Copyright 2011 Stefan Lankes, Chair for Operating Systems,
 *                               RWTH Aachen University
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * This file is part of MetalSVM. 
 */

#ifndef __ARCH_SVM_H__
#define __ARCH_SVM_H__

#include <metalsvm/stddef.h>
#include <asm/page.h>
#ifdef CONFIG_ROCKCREEK
#include <asm/RCCE_lib.h>
#endif

#ifdef __cplusplus
extern "C" {
#endif

#ifdef CONFIG_ROCKCREEK

//#define SVM_WB

#define SVM_STRONG		(1 << 0)
#define SVM_LAZYRELEASE		(1 << 1)
#define SVM_L2			(1 << 4)
#define SVM_STRONG_L2		SVM_STRONG|SVM_L2
#define SVM_LAZYRELEASE_L2	SVM_LAZYRELEASE|SVM_L2

/** @brief Init routine of the SVM subsystem 
 *
 * @return
 * - 0 on success
 * - -ENOMEM not enough memory
 */
int svm_init(void);

/** @brief Memory allocator of the SVM subsystem.
 *
 * Like RCCE function, belongs svmmalloc to the synchronous 
 * function. 
 *
 * @return Pointer to the new memory range
 */
void* svm_malloc(size_t size, uint32_t flags);

/** @brief Frees memory, which is managed by the SVM subsystem
 *
 * Like RCCE function, belongs svmfree to the synchronous function. 
 */
void svm_free(void* addr, size_t size);

int svm_barrier(uint32_t flags);

/** @brief Request for exlusive access 
 *
 * @return
 * - 0 on success
 */
int svm_access_request(size_t addr);

/** @brief Allocate n shared pages
 *
 * @param n number of requested pages
 * @return physical address of the shared pages
 */
size_t shmalloc(uint32_t n);

int svm_alloc_page(size_t addr, page_table_t* pgt);

/** @brief emit page to core ue
 *
 * @return 
 * - 0 on success
 */
int svm_emit_page(size_t addr, int ue);

#ifdef CONFIG_ROCKCREEK
/* @brief invalidate the cache entries for all SVM regions
 */
#ifndef SVM_WB
static inline void svm_invalidate(void)
{
	asm volatile ( ".byte 0x0f; .byte 0x0a;\n" ); // CL1FLUSHMB
}
#else
void svm_invalidate(void);
#endif

/* @brief flushs the cache for all SVM regions
 */
#ifndef SVM_WB
static inline void svm_flush(size_t unused)
{
	// need to write to another line to make sure the write combine buffer gets flushed
	*(volatile int *)RCCE_fool_write_combine_buffer = 1;
}
#else
void svm_flush(size_t addr);
#endif
#endif

/* @brief dumps the some performance counters (e.g. numbers of page migrations)
 * 
 * @retrun
 * - 0 on success
 */
int svm_statistics(void);

#endif

#ifdef __cplusplus
}
#endif

#endif