summaryrefslogtreecommitdiff
path: root/arch/arm64/kernel/head.S
diff options
context:
space:
mode:
authorIngo Molnar <mingo@kernel.org>2018-02-06 21:12:31 +0100
committerIngo Molnar <mingo@kernel.org>2018-02-06 21:12:31 +0100
commit82845079160817cc6ac64e5321bbd935e0a47b3a (patch)
tree0886d1d52428e9db14536cae4b37db896e7c360a /arch/arm64/kernel/head.S
parent32e839dda3ba576943365f0f5817ce5c843137dc (diff)
parent68c5735eaa5e680e701c9a2d1e3c7880bdf5ab66 (diff)
Merge branch 'linus' into sched/urgent, to resolve conflicts
Conflicts: arch/arm64/kernel/entry.S arch/x86/Kconfig include/linux/sched/mm.h kernel/fork.c Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/arm64/kernel/head.S')
-rw-r--r--arch/arm64/kernel/head.S245
1 files changed, 172 insertions, 73 deletions
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index e3cb9fbf96b6..ba3ab04788dc 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -148,6 +148,26 @@ preserve_boot_args:
ENDPROC(preserve_boot_args)
/*
+ * Macro to arrange a physical address in a page table entry, taking care of
+ * 52-bit addresses.
+ *
+ * Preserves: phys
+ * Returns: pte
+ */
+ .macro phys_to_pte, phys, pte
+#ifdef CONFIG_ARM64_PA_BITS_52
+ /*
+ * We assume \phys is 64K aligned and this is guaranteed by only
+ * supporting this configuration with 64K pages.
+ */
+ orr \pte, \phys, \phys, lsr #36
+ and \pte, \pte, #PTE_ADDR_MASK
+#else
+ mov \pte, \phys
+#endif
+ .endm
+
+/*
* Macro to create a table entry to the next page.
*
* tbl: page table address
@@ -156,54 +176,124 @@ ENDPROC(preserve_boot_args)
* ptrs: #imm pointers per table page
*
* Preserves: virt
- * Corrupts: tmp1, tmp2
+ * Corrupts: ptrs, tmp1, tmp2
* Returns: tbl -> next level table page address
*/
.macro create_table_entry, tbl, virt, shift, ptrs, tmp1, tmp2
- lsr \tmp1, \virt, #\shift
- and \tmp1, \tmp1, #\ptrs - 1 // table index
- add \tmp2, \tbl, #PAGE_SIZE
+ add \tmp1, \tbl, #PAGE_SIZE
+ phys_to_pte \tmp1, \tmp2
orr \tmp2, \tmp2, #PMD_TYPE_TABLE // address of next table and entry type
+ lsr \tmp1, \virt, #\shift
+ sub \ptrs, \ptrs, #1
+ and \tmp1, \tmp1, \ptrs // table index
str \tmp2, [\tbl, \tmp1, lsl #3]
add \tbl, \tbl, #PAGE_SIZE // next level table page
.endm
/*
- * Macro to populate the PGD (and possibily PUD) for the corresponding
- * block entry in the next level (tbl) for the given virtual address.
+ * Macro to populate page table entries, these entries can be pointers to the next level
+ * or last level entries pointing to physical memory.
+ *
+ * tbl: page table address
+ * rtbl: pointer to page table or physical memory
+ * index: start index to write
+ * eindex: end index to write - [index, eindex] written to
+ * flags: flags for pagetable entry to or in
+ * inc: increment to rtbl between each entry
+ * tmp1: temporary variable
*
- * Preserves: tbl, next, virt
- * Corrupts: tmp1, tmp2
+ * Preserves: tbl, eindex, flags, inc
+ * Corrupts: index, tmp1
+ * Returns: rtbl
*/
- .macro create_pgd_entry, tbl, virt, tmp1, tmp2
- create_table_entry \tbl, \virt, PGDIR_SHIFT, PTRS_PER_PGD, \tmp1, \tmp2
-#if SWAPPER_PGTABLE_LEVELS > 3
- create_table_entry \tbl, \virt, PUD_SHIFT, PTRS_PER_PUD, \tmp1, \tmp2
-#endif
-#if SWAPPER_PGTABLE_LEVELS > 2
- create_table_entry \tbl, \virt, SWAPPER_TABLE_SHIFT, PTRS_PER_PTE, \tmp1, \tmp2
-#endif
+ .macro populate_entries, tbl, rtbl, index, eindex, flags, inc, tmp1
+.Lpe\@: phys_to_pte \rtbl, \tmp1
+ orr \tmp1, \tmp1, \flags // tmp1 = table entry
+ str \tmp1, [\tbl, \index, lsl #3]
+ add \rtbl, \rtbl, \inc // rtbl = pa next level
+ add \index, \index, #1
+ cmp \index, \eindex
+ b.ls .Lpe\@
+ .endm
+
+/*
+ * Compute indices of table entries from virtual address range. If multiple entries
+ * were needed in the previous page table level then the next page table level is assumed
+ * to be composed of multiple pages. (This effectively scales the end index).
+ *
+ * vstart: virtual address of start of range
+ * vend: virtual address of end of range
+ * shift: shift used to transform virtual address into index
+ * ptrs: number of entries in page table
+ * istart: index in table corresponding to vstart
+ * iend: index in table corresponding to vend
+ * count: On entry: how many extra entries were required in previous level, scales
+ * our end index.
+ * On exit: returns how many extra entries required for next page table level
+ *
+ * Preserves: vstart, vend, shift, ptrs
+ * Returns: istart, iend, count
+ */
+ .macro compute_indices, vstart, vend, shift, ptrs, istart, iend, count
+ lsr \iend, \vend, \shift
+ mov \istart, \ptrs
+ sub \istart, \istart, #1
+ and \iend, \iend, \istart // iend = (vend >> shift) & (ptrs - 1)
+ mov \istart, \ptrs
+ mul \istart, \istart, \count
+ add \iend, \iend, \istart // iend += (count - 1) * ptrs
+ // our entries span multiple tables
+
+ lsr \istart, \vstart, \shift
+ mov \count, \ptrs
+ sub \count, \count, #1
+ and \istart, \istart, \count
+
+ sub \count, \iend, \istart
.endm
/*
- * Macro to populate block entries in the page table for the start..end
- * virtual range (inclusive).
+ * Map memory for specified virtual address range. Each level of page table needed supports
+ * multiple entries. If a level requires n entries the next page table level is assumed to be
+ * formed from n pages.
+ *
+ * tbl: location of page table
+ * rtbl: address to be used for first level page table entry (typically tbl + PAGE_SIZE)
+ * vstart: start address to map
+ * vend: end address to map - we map [vstart, vend]
+ * flags: flags to use to map last level entries
+ * phys: physical address corresponding to vstart - physical memory is contiguous
+ * pgds: the number of pgd entries
*
- * Preserves: tbl, flags
- * Corrupts: phys, start, end, pstate
+ * Temporaries: istart, iend, tmp, count, sv - these need to be different registers
+ * Preserves: vstart, vend, flags
+ * Corrupts: tbl, rtbl, istart, iend, tmp, count, sv
*/
- .macro create_block_map, tbl, flags, phys, start, end
- lsr \phys, \phys, #SWAPPER_BLOCK_SHIFT
- lsr \start, \start, #SWAPPER_BLOCK_SHIFT
- and \start, \start, #PTRS_PER_PTE - 1 // table index
- orr \phys, \flags, \phys, lsl #SWAPPER_BLOCK_SHIFT // table entry
- lsr \end, \end, #SWAPPER_BLOCK_SHIFT
- and \end, \end, #PTRS_PER_PTE - 1 // table end index
-9999: str \phys, [\tbl, \start, lsl #3] // store the entry
- add \start, \start, #1 // next entry
- add \phys, \phys, #SWAPPER_BLOCK_SIZE // next block
- cmp \start, \end
- b.ls 9999b
+ .macro map_memory, tbl, rtbl, vstart, vend, flags, phys, pgds, istart, iend, tmp, count, sv
+ add \rtbl, \tbl, #PAGE_SIZE
+ mov \sv, \rtbl
+ mov \count, #0
+ compute_indices \vstart, \vend, #PGDIR_SHIFT, \pgds, \istart, \iend, \count
+ populate_entries \tbl, \rtbl, \istart, \iend, #PMD_TYPE_TABLE, #PAGE_SIZE, \tmp
+ mov \tbl, \sv
+ mov \sv, \rtbl
+
+#if SWAPPER_PGTABLE_LEVELS > 3
+ compute_indices \vstart, \vend, #PUD_SHIFT, #PTRS_PER_PUD, \istart, \iend, \count
+ populate_entries \tbl, \rtbl, \istart, \iend, #PMD_TYPE_TABLE, #PAGE_SIZE, \tmp
+ mov \tbl, \sv
+ mov \sv, \rtbl
+#endif
+
+#if SWAPPER_PGTABLE_LEVELS > 2
+ compute_indices \vstart, \vend, #SWAPPER_TABLE_SHIFT, #PTRS_PER_PMD, \istart, \iend, \count
+ populate_entries \tbl, \rtbl, \istart, \iend, #PMD_TYPE_TABLE, #PAGE_SIZE, \tmp
+ mov \tbl, \sv
+#endif
+
+ compute_indices \vstart, \vend, #SWAPPER_BLOCK_SHIFT, #PTRS_PER_PTE, \istart, \iend, \count
+ bic \count, \phys, #SWAPPER_BLOCK_SIZE - 1
+ populate_entries \tbl, \count, \istart, \iend, \flags, #SWAPPER_BLOCK_SIZE, \tmp
.endm
/*
@@ -221,14 +311,16 @@ __create_page_tables:
* dirty cache lines being evicted.
*/
adrp x0, idmap_pg_dir
- ldr x1, =(IDMAP_DIR_SIZE + SWAPPER_DIR_SIZE + RESERVED_TTBR0_SIZE)
+ adrp x1, swapper_pg_end
+ sub x1, x1, x0
bl __inval_dcache_area
/*
* Clear the idmap and swapper page tables.
*/
adrp x0, idmap_pg_dir
- ldr x1, =(IDMAP_DIR_SIZE + SWAPPER_DIR_SIZE + RESERVED_TTBR0_SIZE)
+ adrp x1, swapper_pg_end
+ sub x1, x1, x0
1: stp xzr, xzr, [x0], #16
stp xzr, xzr, [x0], #16
stp xzr, xzr, [x0], #16
@@ -244,26 +336,13 @@ __create_page_tables:
adrp x0, idmap_pg_dir
adrp x3, __idmap_text_start // __pa(__idmap_text_start)
-#ifndef CONFIG_ARM64_VA_BITS_48
-#define EXTRA_SHIFT (PGDIR_SHIFT + PAGE_SHIFT - 3)
-#define EXTRA_PTRS (1 << (48 - EXTRA_SHIFT))
-
- /*
- * If VA_BITS < 48, it may be too small to allow for an ID mapping to be
- * created that covers system RAM if that is located sufficiently high
- * in the physical address space. So for the ID map, use an extended
- * virtual range in that case, by configuring an additional translation
- * level.
- * First, we have to verify our assumption that the current value of
- * VA_BITS was chosen such that all translation levels are fully
- * utilised, and that lowering T0SZ will always result in an additional
- * translation level to be configured.
- */
-#if VA_BITS != EXTRA_SHIFT
-#error "Mismatch between VA_BITS and page size/number of translation levels"
-#endif
-
/*
+ * VA_BITS may be too small to allow for an ID mapping to be created
+ * that covers system RAM if that is located sufficiently high in the
+ * physical address space. So for the ID map, use an extended virtual
+ * range in that case, and configure an additional translation level
+ * if needed.
+ *
* 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
@@ -272,21 +351,44 @@ __create_page_tables:
adrp x5, __idmap_text_end
clz x5, x5
cmp x5, TCR_T0SZ(VA_BITS) // default T0SZ small enough?
- b.ge 1f // .. then skip additional level
+ b.ge 1f // .. then skip VA range extension
adr_l x6, idmap_t0sz
str x5, [x6]
dmb sy
dc ivac, x6 // Invalidate potentially stale cache line
- create_table_entry x0, x3, EXTRA_SHIFT, EXTRA_PTRS, x5, x6
-1:
+#if (VA_BITS < 48)
+#define EXTRA_SHIFT (PGDIR_SHIFT + PAGE_SHIFT - 3)
+#define EXTRA_PTRS (1 << (PHYS_MASK_SHIFT - EXTRA_SHIFT))
+
+ /*
+ * If VA_BITS < 48, we have to configure an additional table level.
+ * First, we have to verify our assumption that the current value of
+ * VA_BITS was chosen such that all translation levels are fully
+ * utilised, and that lowering T0SZ will always result in an additional
+ * translation level to be configured.
+ */
+#if VA_BITS != EXTRA_SHIFT
+#error "Mismatch between VA_BITS and page size/number of translation levels"
#endif
- create_pgd_entry x0, x3, x5, x6
+ mov x4, EXTRA_PTRS
+ create_table_entry x0, x3, EXTRA_SHIFT, x4, x5, x6
+#else
+ /*
+ * If VA_BITS == 48, we don't have to configure an additional
+ * translation level, but the top-level table has more entries.
+ */
+ mov x4, #1 << (PHYS_MASK_SHIFT - PGDIR_SHIFT)
+ str_l x4, idmap_ptrs_per_pgd, x5
+#endif
+1:
+ ldr_l x4, idmap_ptrs_per_pgd
mov x5, x3 // __pa(__idmap_text_start)
adr_l x6, __idmap_text_end // __pa(__idmap_text_end)
- create_block_map x0, x7, x3, x5, x6
+
+ map_memory x0, x1, x3, x6, x7, x3, x4, x10, x11, x12, x13, x14
/*
* Map the kernel image (starting with PHYS_OFFSET).
@@ -294,12 +396,13 @@ __create_page_tables:
adrp x0, swapper_pg_dir
mov_q x5, KIMAGE_VADDR + TEXT_OFFSET // compile time __va(_text)
add x5, x5, x23 // add KASLR displacement
- create_pgd_entry x0, x5, x3, x6
+ mov x4, PTRS_PER_PGD
adrp x6, _end // runtime __pa(_end)
adrp x3, _text // runtime __pa(_text)
sub x6, x6, x3 // _end - _text
add x6, x6, x5 // runtime __va(_end)
- create_block_map x0, x7, x3, x5, x6
+
+ map_memory x0, x1, x5, x6, x7, x3, x4, x10, x11, x12, x13, x14
/*
* Since the page tables have been populated with non-cacheable
@@ -307,7 +410,8 @@ __create_page_tables:
* tables again to remove any speculatively loaded cache lines.
*/
adrp x0, idmap_pg_dir
- ldr x1, =(IDMAP_DIR_SIZE + SWAPPER_DIR_SIZE + RESERVED_TTBR0_SIZE)
+ adrp x1, swapper_pg_end
+ sub x1, x1, x0
dmb sy
bl __inval_dcache_area
@@ -388,17 +492,13 @@ ENTRY(el2_setup)
mrs x0, CurrentEL
cmp x0, #CurrentEL_EL2
b.eq 1f
- mrs x0, sctlr_el1
-CPU_BE( orr x0, x0, #(3 << 24) ) // Set the EE and E0E bits for EL1
-CPU_LE( bic x0, x0, #(3 << 24) ) // Clear the EE and E0E bits for EL1
+ mov_q x0, (SCTLR_EL1_RES1 | ENDIAN_SET_EL1)
msr sctlr_el1, x0
mov w0, #BOOT_CPU_MODE_EL1 // This cpu booted in EL1
isb
ret
-1: mrs x0, sctlr_el2
-CPU_BE( orr x0, x0, #(1 << 25) ) // Set the EE bit for EL2
-CPU_LE( bic x0, x0, #(1 << 25) ) // Clear the EE bit for EL2
+1: mov_q x0, (SCTLR_EL2_RES1 | ENDIAN_SET_EL2)
msr sctlr_el2, x0
#ifdef CONFIG_ARM64_VHE
@@ -514,10 +614,7 @@ install_el2_stub:
* requires no configuration, and all non-hyp-specific EL2 setup
* will be done via the _EL1 system register aliases in __cpu_setup.
*/
- /* sctlr_el1 */
- mov x0, #0x0800 // Set/clear RES{1,0} bits
-CPU_BE( movk x0, #0x33d0, lsl #16 ) // Set EE and E0E on BE systems
-CPU_LE( movk x0, #0x30d0, lsl #16 ) // Clear EE and E0E on LE systems
+ mov_q x0, (SCTLR_EL1_RES1 | ENDIAN_SET_EL1)
msr sctlr_el1, x0
/* Coprocessor traps. */
@@ -679,8 +776,10 @@ ENTRY(__enable_mmu)
update_early_cpu_boot_status 0, x1, x2
adrp x1, idmap_pg_dir
adrp x2, swapper_pg_dir
- msr ttbr0_el1, x1 // load TTBR0
- msr ttbr1_el1, x2 // load TTBR1
+ phys_to_ttbr x1, x3
+ phys_to_ttbr x2, x4
+ msr ttbr0_el1, x3 // load TTBR0
+ msr ttbr1_el1, x4 // load TTBR1
isb
msr sctlr_el1, x0
isb