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)
{
diff --git a/include/asm-ppc/mmu.h b/include/asm-ppc/mmu.h
index fa92b90..eda2959 100644
--- a/include/asm-ppc/mmu.h
+++ b/include/asm-ppc/mmu.h
@@ -387,8 +387,10 @@
* FSL Book-E support
*/
-#define MAS0_TLBSEL(x) ((x << 28) & 0x30000000)
-#define MAS0_ESEL(x) ((x << 16) & 0x0FFF0000)
+#define MAS0_TLBSEL_MSK 0x30000000
+#define MAS0_TLBSEL(x) ((x << 28) & MAS0_TLBSEL_MSK)
+#define MAS0_ESEL_MSK 0x0FFF0000
+#define MAS0_ESEL(x) ((x << 16) & MAS0_ESEL_MSK)
#define MAS0_NV(x) ((x) & 0x00000FFF)
#define MAS1_VALID 0x80000000
@@ -474,6 +476,7 @@
extern void disable_tlb(u8 esel);
extern void invalidate_tlb(u8 tlb);
extern void init_tlbs(void);
+extern int find_tlb_idx(void *addr, u8 tlbsel);
extern unsigned int setup_ddr_tlbs(unsigned int memsize_in_meg);