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| author | Timur Tabi <timur@freescale.com> | 2011-10-31 13:30:44 -0500 | 
|---|---|---|
| committer | Kumar Gala <galak@kernel.crashing.org> | 2011-11-08 08:31:06 -0600 | 
| commit | 19e438412416c4cd4066dfa7aca679fe291f13e1 (patch) | |
| tree | 3fdcdf65e520aeb01cc3f2e8a2b4b151896757c1 /arch/powerpc/cpu/mpc85xx/start.S | |
| parent | 452ad61c3feeffbf2b5ff74f0a6797af3ba4882c (diff) | |
| download | olio-uboot-2014.01-19e438412416c4cd4066dfa7aca679fe291f13e1.tar.xz olio-uboot-2014.01-19e438412416c4cd4066dfa7aca679fe291f13e1.zip | |
powerpc/85xx: verify the current address of CCSR before relocating it
Verify that CCSR is actually located where it is supposed to be before
we relocate it.  This is useful in detecting U-Boot configurations that
are broken (e.g. an incorrect value for CONFIG_SYS_CCSRBAR_DEFAULT).
If the current value is wrong, we enter an infinite loop, which is handy
for debuggers.
Signed-off-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Diffstat (limited to 'arch/powerpc/cpu/mpc85xx/start.S')
| -rw-r--r-- | arch/powerpc/cpu/mpc85xx/start.S | 27 | 
1 files changed, 27 insertions, 0 deletions
| diff --git a/arch/powerpc/cpu/mpc85xx/start.S b/arch/powerpc/cpu/mpc85xx/start.S index e519f35d9..d494528bd 100644 --- a/arch/powerpc/cpu/mpc85xx/start.S +++ b/arch/powerpc/cpu/mpc85xx/start.S @@ -411,6 +411,33 @@ create_ccsr_old_tlb:  	msync  	tlbwe +	/* +	 * We have a TLB for what we think is the current (old) CCSR.  Let's +	 * verify that, otherwise we won't be able to move it. +	 * CONFIG_SYS_CCSRBAR_DEFAULT is always a 32-bit number, so we only +	 * need to compare the lower 32 bits of CCSRBAR on CoreNet systems. +	 */ +verify_old_ccsr: +	lis     r0, CONFIG_SYS_CCSRBAR_DEFAULT@h +	ori     r0, r0, CONFIG_SYS_CCSRBAR_DEFAULT@l +#ifdef CONFIG_FSL_CORENET +	lwz	r1, 4(r9)		/* CCSRBARL */ +#else +	lwz	r1, 0(r9)		/* CCSRBAR, shifted right by 12 */ +	slwi	r1, r1, 12 +#endif + +	cmpl	0, r0, r1 + +	/* +	 * If the value we read from CCSRBARL is not what we expect, then +	 * enter an infinite loop.  This will at least allow a debugger to +	 * halt execution and examine TLBs, etc.  There's no point in going +	 * on. +	 */ +infinite_debug_loop: +	bne	infinite_debug_loop +  #ifdef CONFIG_FSL_CORENET  #define CCSR_LAWBARH0	(CONFIG_SYS_CCSRBAR + 0x1000) |