[PATCH 3/3] Avoid accessing GCMP registers when they are not present

[Raghu Gandham <raghu@mips.com>]

From: Jaidev Patwardhan <jaidev@mips.com>

Signed-off-by: Chris Dearman <chris@mips.com>
---

 arch/mips/mti-malta/malta-int.c |   16 +++++++++++++---
 1 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/arch/mips/mti-malta/malta-int.c b/arch/mips/mti-malta/malta-int.c
index 377a925..4c3fca1 100644
--- a/arch/mips/mti-malta/malta-int.c
+++ b/arch/mips/mti-malta/malta-int.c
@@ -411,6 +411,11 @@ static struct gic_intr_map gic_intr_map[GIC_NUM_INTRS] = {
  */
 int __init gcmp_probe(unsigned long addr, unsigned long size)
 {
+       if (mips_revision_sconid != MIPS_REVISION_SCON_ROCIT) {
+               gcmp_present = 0;
+               return gcmp_present;
+       }
+
        if (gcmp_present >= 0)
                return gcmp_present;
 
@@ -479,9 +484,14 @@ void __init arch_init_irq(void)
                GCMPGCB(GICBA) = GIC_BASE_ADDR | GCMP_GCB_GICBA_EN_MSK;
                gic_present = 1;
        } else {
-               _msc01_biu_base = (unsigned long) 
ioremap_nocache(MSC01_BIU_REG_BASE, MSC01_BIU_ADDRSPACE_SZ);
-               gic_present = (REG(_msc01_biu_base, MSC01_SC_CFG) &
-               MSC01_SC_CFG_GICPRES_MSK) >> MSC01_SC_CFG_GICPRES_SHF;
+               if (mips_revision_sconid == MIPS_REVISION_SCON_ROCIT) {
+                       _msc01_biu_base = (unsigned long)
+                                       ioremap_nocache(MSC01_BIU_REG_BASE,
+                                               MSC01_BIU_ADDRSPACE_SZ);
+                       gic_present = (REG(_msc01_biu_base, MSC01_SC_CFG) &
+                                       MSC01_SC_CFG_GICPRES_MSK) >>
+                                       MSC01_SC_CFG_GICPRES_SHF;
+               }
        }
        if (gic_present)
                pr_debug("GIC present\n");