Merge remote-tracking branch 'lts/linux-4.4.y' into linux-linaro-lsk-v4.4
[firefly-linux-kernel-4.4.55.git] / arch / arm64 / mm / proc.S
index 18201e9e8cc71c22d017a9573cf722bdab63de74..a92738e8b1eb670772e9314643eadc29d7f954ba 100644 (file)
@@ -152,7 +152,33 @@ alternative_else
 alternative_endif
 ENDPROC(cpu_do_switch_mm)
 
-       .section ".text.init", #alloc, #execinstr
+       .pushsection ".idmap.text", "ax"
+/*
+ * void idmap_cpu_replace_ttbr1(phys_addr_t new_pgd)
+ *
+ * This is the low-level counterpart to cpu_replace_ttbr1, and should not be
+ * called by anything else. It can only be executed from a TTBR0 mapping.
+ */
+ENTRY(idmap_cpu_replace_ttbr1)
+       mrs     x2, daif
+       msr     daifset, #0xf
+
+       adrp    x1, empty_zero_page
+       msr     ttbr1_el1, x1
+       isb
+
+       tlbi    vmalle1
+       dsb     nsh
+       isb
+
+       msr     ttbr1_el1, x0
+       isb
+
+       msr     daif, x2
+
+       ret
+ENDPROC(idmap_cpu_replace_ttbr1)
+       .popsection
 
 /*
  *     __cpu_setup