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From: Chris Holgate <chris@zynaptic.com>
To: ecos-devel@ecos.sourceware.org
Subject: Minor fix for CortexM vectors.S
Date: Tue, 18 Nov 2008 11:42:00 -0000	[thread overview]
Message-ID: <1227008854.29306.73.camel@hercules.zynaptic.com> (raw)

Hi folks,

This is a minor fix that I found while building the ROM based target for
my STM32 board.  The hal_switch_state_vsr can generate invalid
EXC_RETURN values in the link register for certain alignments - the fix
is to ensure that bit 1 is always cleared.  It's also possible to
reclaim a bit of RAM for the interrupt stack:

*** cvs-14.11.08/ecos/packages/hal/cortexm/arch/current/src/vectors.S
2008-11-03 14:53:51.000000000 +0000
---
working-14.11.08/ecos/packages/hal/cortexm/arch/current/src/vectors.S
2008-11-18 11:10:31.000000000 +0000
***************
*** 129,140 ****
--- 129,142 ----
          isb                             // Insert a barrier
          
          msr     psp,sp                  // Copy SP to PSP
+         ldr     sp,=hal_startup_stack   // Reset SP to top of RAM
  
  #if !defined(CYGPKG_KERNEL)
          sub     sp,#(CYGNUM_HAL_COMMON_INTERRUPTS_STACK_SIZE/2)
  #endif        
          
          orr     lr,#0xD                 // Adjust return link
+         bic     lr,#0x2
          bx      lr                      // Return to init code on PSP

Chris.

             reply	other threads:[~2008-11-18 11:42 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-11-18 11:42 Chris Holgate [this message]
2008-11-19 16:31 ` Nick Garnett
2008-11-19 18:00   ` Chris Holgate
2008-11-19 18:12     ` Nick Garnett
2008-11-19 19:21       ` Chris Holgate

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