/**************************************************************************** * boards/arm/stm32l4/nucleo-l496zg/scripts/memory.ld * * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. The * ASF licenses this file to you 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. * ****************************************************************************/ /* The STM32F746NGH6 has 1024Kb of main FLASH memory. This FLASH memory can * be accessed from either the AXIM interface at address 0x0800:0000 or from * the ITCM interface at address 0x0020:0000. * * Additional information, including the option bytes, is available at at * FLASH at address 0x1ff0:0000 (AXIM) or 0x0010:0000 (ITCM). * * In the STM32F746NGH6, two different boot spaces can be selected through * the BOOT pin and the boot base address programmed in the BOOT_ADD0 and * BOOT_ADD1 option bytes: * * 1) BOOT=0: Boot address defined by user option byte BOOT_ADD0[15:0]. * ST programmed value: Flash on ITCM at 0x0020:0000 * 2) BOOT=1: Boot address defined by user option byte BOOT_ADD1[15:0]. * ST programmed value: System bootloader at 0x0010:0000 * * NuttX does not modify these option bytes. On the unmodified STM32F746G * DISCO board, the BOOT0 pin is at ground so by default, the STM32 will boot * to address 0x0020:0000 in ITCM FLASH. * * The STM32F746NGH6 also has 320Kb of data SRAM (in addition to ITCM SRAM). * SRAM is split up into three blocks: * * 1) 64Kb of DTCM SRM beginning at address 0x2000:0000 * 2) 240Kb of SRAM1 beginning at address 0x2001:0000 * 3) 16Kb of SRAM2 beginning at address 0x2004:c000 * * 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 boards/stm32f746g-disco/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 alignment * 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 112KB SRAM region is as follows: * * 0x20001 0000: Kernel .data region. Typical size: 0.1KB * ------- ---- Kernel .bss region. Typical size: 1.8KB * 0x20001 0800: Kernel IDLE thread stack (approximate). Size is * determined by CONFIG_IDLETHREAD_STACKSIZE and * adjustments for alignment. Typical is 1KB. * ------- ---- Padded to 4KB * 0x20001 1000: User .data region. Size is variable. * ------- ---- User .bss region Size is variable. * 0x20001 2000: Beginning of kernel heap. Size determined by * CONFIG_MM_KERNEL_HEAPSIZE. * ------- ---- Beginning of user heap. Can vary with other settings. * 0x20004 c000: End+1 of SRAM1 */ MEMORY { /* ITCM boot address */ itcm (rwx) : ORIGIN = 0x00200000, LENGTH = 1024K /* 1024KB FLASH */ kflash (rx) : ORIGIN = 0x08000000, LENGTH = 128K uflash (rx) : ORIGIN = 0x08020000, LENGTH = 128K xflash (rx) : ORIGIN = 0x08040000, LENGTH = 768K /* 240KB of contiguous SRAM1 */ ksram (rwx) : ORIGIN = 0x20010000, LENGTH = 4K usram (rwx) : ORIGIN = 0x20011000, LENGTH = 4K xsram (rwx) : ORIGIN = 0x20012000, LENGTH = 240K - 8K /* DTCM SRAM */ dtcm (rwx) : ORIGIN = 0x20000000, LENGTH = 64K sram2 (rwx) : ORIGIN = 0x2004c000, LENGTH = 16K }