From: Joseph Lo Date: Tue, 19 Feb 2013 10:16:13 +0000 (+0800) Subject: ARM: tegra: don't unlock MMIO access to DBGLAR X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=b095ae2b9f35c838257786de27e550d62bd7c763;p=deliverable%2Flinux.git ARM: tegra: don't unlock MMIO access to DBGLAR There is no need to unlock MMIO access to the DBGLAR all the time. Doing so may even cause problems if a SW bug causes writes to that MMIO region. Cortex-A15 processors do not support the CP14 register write the code currently uses to unlock the DBGLAR; the instruction throws an undefined instruction exceptions. This prevents tegra_secondary_startup() from executing on Tegra114, and hence prevents SMP. Remove the code that unlocks this access. Signed-off-by: Joseph Lo Signed-off-by: Stephen Warren --- diff --git a/arch/arm/mach-tegra/headsmp.S b/arch/arm/mach-tegra/headsmp.S index fd473f2b4c3d..045c16f2dd51 100644 --- a/arch/arm/mach-tegra/headsmp.S +++ b/arch/arm/mach-tegra/headsmp.S @@ -7,8 +7,5 @@ ENTRY(tegra_secondary_startup) bl v7_invalidate_l1 - /* Enable coresight */ - mov32 r0, 0xC5ACCE55 - mcr p14, 0, r0, c7, c12, 6 b secondary_startup ENDPROC(tegra_secondary_startup) diff --git a/arch/arm/mach-tegra/reset-handler.S b/arch/arm/mach-tegra/reset-handler.S index ff7b45c6c2a0..1676aba5e7b8 100644 --- a/arch/arm/mach-tegra/reset-handler.S +++ b/arch/arm/mach-tegra/reset-handler.S @@ -41,9 +41,6 @@ */ ENTRY(tegra_resume) bl v7_invalidate_l1 - /* Enable coresight */ - mov32 r0, 0xC5ACCE55 - mcr p14, 0, r0, c7, c12, 6 cpu_id r0 cmp r0, #0 @ CPU0?