source: mainline/boot/arch/arm32/include/mm.h@ aaae6d9

/*
 * Copyright (c) 2007 Pavel Jancik
 * Copyright (c) 2007 Michal Kebrt
 * 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.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
 */

/** @addtogroup arm32boot
 * @{
 */
/** @file
 * @brief Memory management used while booting the kernel.
 *
 * So called "section" paging is used while booting the kernel. The term
 * "section" comes from the ARM architecture specification and stands for the
 * following: one-level paging, 1MB sized pages, 4096 entries in the page
 * table.
 */

#ifndef BOOT_arm32__MM_H
#define BOOT_arm32__MM_H

#include <typedefs.h>

/** Describe "section" page table entry (one-level paging with 1 MB sized pages). */
#define PTE_DESCRIPTOR_SECTION  0x02
/** Shift of memory address in section descriptor */
#define PTE_SECTION_SHIFT  20

/** Page table access rights: user - no access, kernel - read/write. */
#define PTE_AP_USER_NO_KERNEL_RW  0x01

/** Start of memory mapped I/O area for GTA02 */
#define GTA02_IOMEM_START  0x48000000
/** End of memory mapped I/O area for GTA02 */
#define GTA02_IOMEM_END  0x60000000

/** Start of ram memory on BBxM */
#define BBXM_RAM_START   0x80000000
/** Start of ram memory on BBxM */
#define BBXM_RAM_END   0xc0000000

/** Start of ram memory on AM335x */
#define AM335x_RAM_START   0x80000000
/** End of ram memory on AM335x */
#define AM335x_RAM_END     0xC0000000

/** Start of ram memory on BCM2835 */
#define BCM2835_RAM_START   0
/** End of ram memory on BCM2835 */
#define BCM2835_RAM_END     0x20000000

/* Page table level 0 entry - "section" format is used
 * (one-level paging, 1 MB sized pages). Used only while booting the kernel.
 */
typedef struct {
        unsigned int descriptor_type : 2;
        unsigned int bufferable : 1;
        unsigned int cacheable : 1;
        unsigned int xn : 1;
        unsigned int domain : 4;
        unsigned int should_be_zero_1 : 1;
        unsigned int access_permission_0 : 2;
        unsigned int tex : 3;
        unsigned int access_permission_1 : 1;
        unsigned int shareable : 1;
        unsigned int non_global : 1;
        unsigned int should_be_zero_2 : 1;
        unsigned int non_secure : 1;
        unsigned int section_base_addr : 12;
} __attribute__((packed)) pte_level0_section_t;

extern void mmu_start(void);

#endif

/** @}
 */