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Diffstat (limited to 'arch/arm64/include/asm/assembler.h')
-rw-r--r--arch/arm64/include/asm/assembler.h31
1 files changed, 27 insertions, 4 deletions
diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h
index dc422fa437c2..5846145be523 100644
--- a/arch/arm64/include/asm/assembler.h
+++ b/arch/arm64/include/asm/assembler.h
@@ -360,6 +360,20 @@ alternative_cb_end
.endm
/*
+ * idmap_get_t0sz - get the T0SZ value needed to cover the ID map
+ *
+ * Calculate the maximum allowed value for TCR_EL1.T0SZ so that the
+ * entire ID map region can be mapped. As T0SZ == (64 - #bits used),
+ * this number conveniently equals the number of leading zeroes in
+ * the physical address of _end.
+ */
+ .macro idmap_get_t0sz, reg
+ adrp \reg, _end
+ orr \reg, \reg, #(1 << VA_BITS_MIN) - 1
+ clz \reg, \reg
+ .endm
+
+/*
* tcr_compute_pa_size - set TCR.(I)PS to the highest supported
* ID_AA64MMFR0_EL1.PARange value
*
@@ -466,6 +480,18 @@ alternative_endif
.endm
/*
+ * load_ttbr1 - install @pgtbl as a TTBR1 page table
+ * pgtbl preserved
+ * tmp1/tmp2 clobbered, either may overlap with pgtbl
+ */
+ .macro load_ttbr1, pgtbl, tmp1, tmp2
+ phys_to_ttbr \tmp1, \pgtbl
+ offset_ttbr1 \tmp1, \tmp2
+ msr ttbr1_el1, \tmp1
+ isb
+ .endm
+
+/*
* To prevent the possibility of old and new partial table walks being visible
* in the tlb, switch the ttbr to a zero page when we invalidate the old
* records. D4.7.1 'General TLB maintenance requirements' in ARM DDI 0487A.i
@@ -478,10 +504,7 @@ alternative_endif
isb
tlbi vmalle1
dsb nsh
- phys_to_ttbr \tmp, \page_table
- offset_ttbr1 \tmp, \tmp2
- msr ttbr1_el1, \tmp
- isb
+ load_ttbr1 \page_table, \tmp, \tmp2
.endm
/*