[POWERPC] Use SLB size from the device tree

Currently we hardwire the number of SLBs to 64, but PAPR says we
should use the ibm,slb-size property to obtain the number of SLB
entries.  This uses this property instead of assuming 64.  If no
property is found, we assume 64 entries as before.

This soft patches the SLB handler, so it shouldn't change performance
at all.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 3 insertions, 0 deletions

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);