nuttx/boards/arm/gd32f4/gd32f450zk-aiotbox/scripts/memory.ld

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/****************************************************************************
* boards/arm/gd32f4/gd32f450zk-eval/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 GD32F450ZKT6 has 3072Kb of FLASH beginning at address 0x0800:0000 and
* 256Kb of SRAM. SRAM is split up into four blocks:
*
* 1) 112KB of SRAM beginning at address 0x2000:0000
* 2) 16KB of SRAM beginning at address 0x2001:c000
* 3) 64KB of SRAM beginning at address 0x2002:0000
* 4) 64KB of TCMSRAM beginning at address 0x1000:0000
*
* 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. 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:
*
* 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 1000: User .data region. Size is variable.
* ------- ---- User .bss region Size is variable.
* 0x20000 2000: Beginning of kernel heap. Size determined by
* CONFIG_MM_KERNEL_HEAPSIZE.
* ------- ---- Beginning of user heap. Can vary with other settings.
* 0x20001 c000: 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
/* 112Kb of contiguous SRAM */
ksram (rwx) : ORIGIN = 0x20000000, LENGTH = 4K
usram (rwx) : ORIGIN = 0x20001000, LENGTH = 4K
xsram (rwx) : ORIGIN = 0x20002000, LENGTH = 104K
}