arch/arm: Fix LPC2378 to work again

[acassis]

Summary

Olimex LPC-2378-STK was the first board I ran NuttX in 2010. Then in 2023 I found this board on eBay and decided to buy it to try NuttX on it again, but for my disappointment it was not working: https://acassis.wordpress.com/2023/04/01/testing-nuttx-again-on-olimex-lpc2378-stk-board/

Then I opened an Issue: #19201 and Xiang Xiao and ldube helped me to get it working again.

Impact

This commit proves that NuttX still working for ARM7TDMI.

Testing

NuttShell (NSH) NuttX-13.0.0-RC0                                             
nsh> uname -a
NuttX 13.0.0-RC0 bcac56ed20-dirty Jun 28 2026 16:05:05 arm olimex-lpc2378    
nsh> mount
nsh: mount: missing required argument(s)                                     
nsh> help
help usage:  help [-v] [<cmd>]                                               
                                                                             
    .           cd          expr        mv          usleep      unset        
    [           cp          false       printf      source      uptime       
    ?           cmp         help        pwd         test        watch        
    alias       dirname     hexdump     rm          time        xd           
    unalias     dmesg       ls          rmdir       true                          
    basename    echo        mkdir       set         truncate                      
    break       exec        mkrd        kill        uname                         
    cat         exit        mount       sleep       umount                        
nsh> uptime                                                                       
00:00:34 up  0:00, load average: 0.00, 0.00, 0.00                                 
nsh>

[acassis]

@jerpelea please add this fix to NuttX V13-RC1

[github-actions]

MemBrowse Memory Report

No memory changes detected for:

• arduino-mega2560
• esp32-devkitc
• hifive1-revb
• mirtoo
• qemu-armv8a
• qemu-intel64
• rx65n-rsk2mb
• s698pm-dkit
• stm32-nucleo-f103rb

[xiaoxiang781216]

ci error is fixed by apache/nuttx-apps#3568

[simbit18]

Hi @acassis, The PR apache/nuttx-apps#3568 has been merged. Please rebase

[simbit18]

@acassis This error occurs

====================================================================================
Configuration/Tool: olimex-lpc2378/nsh,CONFIG_ARM_TOOLCHAIN_GNU_EABI
2026-06-29 07:28:40
------------------------------------------------------------------------------------
  Cleaning...
  Configuring...
  Disabling CONFIG_ARM_TOOLCHAIN_GNU_EABI
  Enabling CONFIG_ARM_TOOLCHAIN_GNU_EABI
  Building NuttX...
Error: chip/lpc23xx_decodeirq.c:87:18: error: 'lpc23xx_decodeirq' defined but not used [-Werror=unused-function]
   87 | static uint32_t *lpc23xx_decodeirq(uint32_t *regs)
      |                  ^~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
make[1]: *** [Makefile:179: lpc23xx_decodeirq.o] Error 1
make[1]: Target 'libarch.a' not remade because of errors.
make: *** [tools/LibTargets.mk:170: arch/arm/src/libarch.a] Error 2
make: Target 'all' not remade because of errors.
/github/workspace/sources/nuttx/tools/testbuild.sh: line 397: /github/workspace/sources/nuttx/../nuttx/nuttx.manifest: No such file or directory
  [1/1] Normalize olimex-lpc2378/nsh
/github/workspace/sources/nuttx /github/workspace/sources/nuttx
HEAD detached at pull/19233/merge
nothing to commit, working tree clean
/github/workspace/sources/nuttx
/github/workspace/sources/apps /github/workspace/sources/nuttx
On branch master
Your branch is up to date with 'origin/master'.

nothing to commit, working tree clean
/github/workspace/sources/nuttx
Wait 19 seconds (60 backoff)
Build Attempt 2 of 4
====================================================================================