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| author | Gregory Nutt <gnutt@nuttx.org> | 2014-01-07 08:38:00 -0600 |
|---|---|---|
| committer | Gregory Nutt <gnutt@nuttx.org> | 2014-01-07 08:38:00 -0600 |
| commit | b55b8aa1fa19eea6b3684b76cf9c35f45de43f2b (patch) | |
| tree | 77eb97747d3f9bcfc7fe2f073ea263a983ea39dd | |
| parent | b859b662f1cf99d863aeebe04f5d9dbc76a0a835 (diff) | |
| download | px4-nuttx-b55b8aa1fa19eea6b3684b76cf9c35f45de43f2b.tar.gz px4-nuttx-b55b8aa1fa19eea6b3684b76cf9c35f45de43f2b.tar.bz2 px4-nuttx-b55b8aa1fa19eea6b3684b76cf9c35f45de43f2b.zip | |
Add more nops after enabling MMU for Cortex-A8
| -rw-r--r-- | nuttx/ChangeLog | 3 | ||||
| -rw-r--r-- | nuttx/arch/arm/src/armv7-a/arm_head.S | 11 | ||||
| -rw-r--r-- | nuttx/arch/arm/src/armv7-a/arm_pghead.S | 13 |
3 files changed, 10 insertions, 17 deletions
diff --git a/nuttx/ChangeLog b/nuttx/ChangeLog index 32e9073fd..cbf96864e 100644 --- a/nuttx/ChangeLog +++ b/nuttx/ChangeLog @@ -6378,4 +6378,7 @@ problems for assembly language. How to prevent the integer over- flow warnings? (2014-1-6). * arch/arm/src/a1x/a1x_serial.c: Handle BUSY interrupt (2014-1-6). + * arch/arm/src/armv7-a/arm_head.S and arm_pghead.S: Add more nop's + after enabling the MMU. The cortex-a8 seems to need these + (2014-1-7). diff --git a/nuttx/arch/arm/src/armv7-a/arm_head.S b/nuttx/arch/arm/src/armv7-a/arm_head.S index b5bab0022..bce82d50b 100644 --- a/nuttx/arch/arm/src/armv7-a/arm_head.S +++ b/nuttx/arch/arm/src/armv7-a/arm_head.S @@ -505,14 +505,9 @@ __start: /* Then write the configured control register */ mcr CP15_SCTLR(r0) /* Write control reg */ - - /* Read the Main ID register. This will be available in R1 after - * MMU trampoline (not currently used) - */ - - mrc CP15_MIDR(r1) /* Read main id reg */ - mov r1, r1 /* Null-avoiding nop */ - mov r1, r1 /* Null-avoiding nop */ + .rept 12 /* Cortex A8 wants lots of NOPs here */ + nop + .endr /* And "jump" to .Lvstart in the newly mapped virtual address space */ diff --git a/nuttx/arch/arm/src/armv7-a/arm_pghead.S b/nuttx/arch/arm/src/armv7-a/arm_pghead.S index a11570515..36497e755 100644 --- a/nuttx/arch/arm/src/armv7-a/arm_pghead.S +++ b/nuttx/arch/arm/src/armv7-a/arm_pghead.S @@ -1,7 +1,7 @@ /**************************************************************************** * arch/arm/src/armv7-a/arm_pghead.S * - * Copyright (C) 2013 Gregory Nutt. All rights reserved. + * Copyright (C) 2013-2014 Gregory Nutt. All rights reserved. * Author: Gregory Nutt <gnutt@nuttx.org> * * Redistribution and use in source and binary forms, with or without @@ -491,14 +491,9 @@ __start: /* Then write the configured control register */ mcr CP15_SCTLR(r0) /* Write control reg */ - - /* Read the Main ID register. This will be available in R1 after - * MMU trampoline (not currently used) - */ - - mrc CP15_MIDR(r1) /* Read main id reg */ - mov r1, r1 /* Null-avoiding nop */ - mov r1, r1 /* Null-avoiding nop */ + .rept 12 /* Cortex A8 wants lots of NOPs here */ + nop + .endr /* And "jump" to .Lvstart in the newly mapped virtual address space */ |