ppc/85xx: Add a simple function to search the TLB
Allow us to search the TLB array based on an address. This is useful
if we want to change an entry but dont know where it happens to be
located.
For example, the boot page mapping we use on MP or the flash TLB that
we change the WIMGE settings for after we've relocated.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
diff --git a/cpu/mpc85xx/tlb.c b/cpu/mpc85xx/tlb.c
index f3d3080..0497a29 100644
--- a/cpu/mpc85xx/tlb.c
+++ b/cpu/mpc85xx/tlb.c
@@ -106,6 +106,33 @@
return ;
}
+static void tlbsx (const volatile unsigned *addr)
+{
+ __asm__ __volatile__ ("tlbsx 0,%0" : : "r" (addr), "m" (*addr));
+}
+
+/* return -1 if we didn't find anything */
+int find_tlb_idx(void *addr, u8 tlbsel)
+{
+ u32 _mas0, _mas1;
+
+ /* zero out Search PID, AS */
+ mtspr(MAS6, 0);
+
+ tlbsx(addr);
+
+ _mas0 = mfspr(MAS0);
+ _mas1 = mfspr(MAS1);
+
+ /* we found something, and its in the TLB we expect */
+ if ((MAS1_VALID & _mas1) &&
+ (MAS0_TLBSEL(tlbsel) == (_mas0 & MAS0_TLBSEL_MSK))) {
+ return ((_mas0 & MAS0_ESEL_MSK) >> 16);
+ }
+
+ return -1;
+}
+
#ifdef CONFIG_ADDR_MAP
void init_addr_map(void)
{