/**************************************************************************** * configs/stm32f4discovery/scripts/memory.ld * * Copyright (C) 2013 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. 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. * 3. Neither the name NuttX 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 OWNER 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. * ****************************************************************************/ /* The STM32L476VG has 1024Kb of FLASH beginning at address 0x0800:0000, * 96Kb of SRAM beginning at address 0x2000:0000, and 32Kb of SRAM2 beginning * at address 0x1000:0000. The SRAM2 has special properties (e.g. parity * check, separate power domain for retention in low power modes, write * protection). Alas, it is non-contiguous with main SRAM. * When booting from FLASH, * * FLASH memory is aliased to address 0x0000:0000 where the code expects to * begin execution by jumping to the entry point in the 0x0800:0000 address * range. * * For MPU support, the kernel-mode NuttX section is assumed to be 128Kb of * FLASH and 4Kb of SRAM. That is an excessive amount for the kernel which * should fit into 64KB and, of course, can be optimized as needed (See * also configs/stm32f4discovery/scripts/kernel-space.ld). Allowing the * additional does permit addition debug instrumentation to be added to the * kernel space without overflowing the partition. * * Alignment of the user space FLASH partition is also a critical factor: * The user space FLASH partition will be spanned with a single region of * size 2**n bytes. The alignment of the user-space region must be the same. * As a consequence, as the user-space increases in size, the alignmment * requirement also increases. * * This alignment requirement means that the largest user space FLASH region * you can have will be 512KB at it would have to be positioned at * 0x08800000. If you change this address, don't forget to change the * CONFIG_NUTTX_USERSPACE configuration setting to match and to modify * the check in kernel/userspace.c. * * For the same reasons, the maximum size of the SRAM mapping is limited to * 4KB. Both of these alignment limitations could be reduced by using * multiple regions to map the FLASH/SDRAM range or perhaps with some * clever use of subregions. * * A detailed memory map for the 96KB SRAM region is as follows: * * 0x20000 0000: Kernel .data region. Typical size: 0.1KB * ------- ---- Kernel .bss region. Typical size: 1.8KB * 0x20000 0800: Kernel IDLE thread stack (approximate). Size is * determined by CONFIG_IDLETHREAD_STACKSIZE and * adjustments for alignment. Typical is 1KB. * ------- ---- Padded to 4KB * 0x20000 2000: User .data region. Size is variable. * ------- ---- User .bss region Size is variable. * 0x20000 4000: Beginning of kernel heap. Size determined by * CONFIG_MM_KERNEL_HEAPSIZE. * ------- ---- Beginning of user heap. Can vary with other settings. * 0x20001 8000: End+1 of CPU RAM */ MEMORY { /* 1024Kb FLASH */ kflash (rx) : ORIGIN = 0x08000000, LENGTH = 128K uflash (rx) : ORIGIN = 0x08020000, LENGTH = 128K xflash (rx) : ORIGIN = 0x08040000, LENGTH = 768K /* 96Kb of contiguous SRAM */ ksram (rwx) : ORIGIN = 0x20000000, LENGTH = 8K usram (rwx) : ORIGIN = 0x20001000, LENGTH = 8K xsram (rwx) : ORIGIN = 0x20002000, LENGTH = 80K }