6 files changed, 25 insertions, 4 deletions

diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
index acc0d247d3c3..6c2d8836f77d 100644
--- a/arch/powerpc/kernel/prom.c
+++ b/arch/powerpc/kernel/prom.c
@@ -583,6 +583,20 @@ static void __init check_cpu_pa_features(unsigned long node)
                       ibm_pa_features, ARRAY_SIZE(ibm_pa_features));
 }
 
+#ifdef CONFIG_PPC64
+static void __init check_cpu_slb_size(unsigned long node)
+{
+        u32 *slb_size_ptr;
+
+        slb_size_ptr = of_get_flat_dt_prop(node, "ibm,slb-size", NULL);
+        if (slb_size_ptr != NULL) {
+                mmu_slb_size = *slb_size_ptr;
+        }
+}
+#else
+#define check_cpu_slb_size(node) do { } while(0)
+#endif
+
 static struct feature_property {
         const char *name;
         u32 min_value;
@@ -713,6 +727,7 @@ static int __init early_init_dt_scan_cpus(unsigned long node,
 
         check_cpu_feature_properties(node);
         check_cpu_pa_features(node);
+        check_cpu_slb_size(node);
 
 #ifdef CONFIG_PPC_PSERIES
         if (nthreads > 1)
diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index f09730bf3a33..cbbd8b0bc8f4 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -96,6 +96,7 @@ int mmu_vmalloc_psize = MMU_PAGE_4K;
 int mmu_io_psize = MMU_PAGE_4K;
 int mmu_kernel_ssize = MMU_SEGSIZE_256M;
 int mmu_highuser_ssize = MMU_SEGSIZE_256M;
+u16 mmu_slb_size = 64;
 #ifdef CONFIG_HUGETLB_PAGE
 int mmu_huge_psize = MMU_PAGE_16M;
 unsigned int HPAGE_SHIFT;
diff --git a/arch/powerpc/mm/slb.c b/arch/powerpc/mm/slb.c
index 27922dff8b94..3cf0802cd2b6 100644
--- a/arch/powerpc/mm/slb.c
+++ b/arch/powerpc/mm/slb.c
@@ -256,6 +256,7 @@ void slb_initialize(void)
         static int slb_encoding_inited;
         extern unsigned int *slb_miss_kernel_load_linear;
         extern unsigned int *slb_miss_kernel_load_io;
+        extern unsigned int *slb_compare_rr_to_size;
 
         /* Prepare our SLB miss handler based on our page size */
         linear_llp = mmu_psize_defs[mmu_linear_psize].sllp;
@@ -269,6 +270,8 @@ void slb_initialize(void)
                                    SLB_VSID_KERNEL | linear_llp);
                 patch_slb_encoding(slb_miss_kernel_load_io,
                                    SLB_VSID_KERNEL | io_llp);
+                patch_slb_encoding(slb_compare_rr_to_size,
+                                   mmu_slb_size);
 
                 DBG("SLB: linear  LLP = %04x\n", linear_llp);
                 DBG("SLB: io      LLP = %04x\n", io_llp);
diff --git a/arch/powerpc/mm/slb_low.S b/arch/powerpc/mm/slb_low.S
index 1328a81a84aa..657f6b37e9df 100644
--- a/arch/powerpc/mm/slb_low.S
+++ b/arch/powerpc/mm/slb_low.S
@@ -227,8 +227,9 @@ END_FW_FTR_SECTION_IFSET(FW_FEATURE_ISERIES)
 
 7:      ld      r10,PACASTABRR(r13)
         addi    r10,r10,1
-        /* use a cpu feature mask if we ever change our slb size */
-        cmpldi  r10,SLB_NUM_ENTRIES
+        /* This gets soft patched on boot. */
+_GLOBAL(slb_compare_rr_to_size)
+        cmpldi  r10,0
 
         blt+    4f
         li      r10,SLB_NUM_BOLTED
diff --git a/arch/powerpc/platforms/pasemi/setup.c b/arch/powerpc/platforms/pasemi/setup.c
index 5748194a667f..6d7d068ceba0 100644
--- a/arch/powerpc/platforms/pasemi/setup.c
+++ b/arch/powerpc/platforms/pasemi/setup.c
@@ -36,6 +36,7 @@
 #include <asm/mpic.h>
 #include <asm/smp.h>
 #include <asm/time.h>
+#include <asm/mmu.h>
 
 #include <pcmcia/ss.h>
 #include <pcmcia/cistpl.h>
@@ -302,7 +303,7 @@ static int pas_machine_check_handler(struct pt_regs *regs)
                 int i;
 
                 printk(KERN_ERR "slb contents:\n");
-                for (i = 0; i < SLB_NUM_ENTRIES; i++) {
+                for (i = 0; i < mmu_slb_size; i++) {
                         asm volatile("slbmfee  %0,%1" : "=r" (e) : "r" (i));
                         asm volatile("slbmfev  %0,%1" : "=r" (v) : "r" (i));
                         printk(KERN_ERR "%02d %016lx %016lx\n", i, e, v);
diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c
index 381d467cf55b..c60d123e9f1f 100644
--- a/arch/powerpc/xmon/xmon.c
+++ b/arch/powerpc/xmon/xmon.c
@@ -2543,7 +2543,7 @@ static void dump_slb(void)
 
         printf("SLB contents of cpu %x\n", smp_processor_id());
 
-        for (i = 0; i < SLB_NUM_ENTRIES; i++) {
+        for (i = 0; i < mmu_slb_size; i++) {
                 asm volatile("slbmfee  %0,%1" : "=r" (tmp) : "r" (i));
                 printf("%02d %016lx ", i, tmp);