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-rw-r--r--arch/arm64/kernel/head.S69
1 files changed, 39 insertions, 30 deletions
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index c68cca5..0fd5650 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -26,6 +26,7 @@
#include <asm/assembler.h>
#include <asm/ptrace.h>
#include <asm/asm-offsets.h>
+#include <asm/cache.h>
#include <asm/cputype.h>
#include <asm/memory.h>
#include <asm/thread_info.h>
@@ -229,7 +230,11 @@ ENTRY(set_cpu_boot_mode_flag)
cmp w20, #BOOT_CPU_MODE_EL2
b.ne 1f
add x1, x1, #4
-1: str w20, [x1] // This CPU has booted in EL1
+1: dc cvac, x1 // Clean potentially dirty cache line
+ dsb sy
+ str w20, [x1] // This CPU has booted in EL1
+ dc civac, x1 // Clean&invalidate potentially stale cache line
+ dsb sy
ret
ENDPROC(set_cpu_boot_mode_flag)
@@ -240,8 +245,9 @@ ENDPROC(set_cpu_boot_mode_flag)
* This is not in .bss, because we set it sufficiently early that the boot-time
* zeroing of .bss would clobber it.
*/
- .pushsection .data
+ .pushsection .data..cacheline_aligned
ENTRY(__boot_cpu_mode)
+ .align L1_CACHE_SHIFT
.long BOOT_CPU_MODE_EL2
.long 0
.popsection
@@ -384,26 +390,18 @@ ENDPROC(__calc_phys_offset)
* Preserves: tbl, flags
* Corrupts: phys, start, end, pstate
*/
- .macro create_block_map, tbl, flags, phys, start, end, idmap=0
+ .macro create_block_map, tbl, flags, phys, start, end
lsr \phys, \phys, #BLOCK_SHIFT
- .if \idmap
- and \start, \phys, #PTRS_PER_PTE - 1 // table index
- .else
lsr \start, \start, #BLOCK_SHIFT
and \start, \start, #PTRS_PER_PTE - 1 // table index
- .endif
orr \phys, \flags, \phys, lsl #BLOCK_SHIFT // table entry
- .ifnc \start,\end
lsr \end, \end, #BLOCK_SHIFT
and \end, \end, #PTRS_PER_PTE - 1 // table end index
- .endif
9999: str \phys, [\tbl, \start, lsl #3] // store the entry
- .ifnc \start,\end
add \start, \start, #1 // next entry
add \phys, \phys, #BLOCK_SIZE // next block
cmp \start, \end
b.ls 9999b
- .endif
.endm
/*
@@ -412,10 +410,19 @@ ENDPROC(__calc_phys_offset)
* - identity mapping to enable the MMU (low address, TTBR0)
* - first few MB of the kernel linear mapping to jump to once the MMU has
* been enabled, including the FDT blob (TTBR1)
- * - UART mapping if CONFIG_EARLY_PRINTK is enabled (TTBR1)
+ * - pgd entry for fixed mappings (TTBR1)
*/
__create_page_tables:
pgtbl x25, x26, x24 // idmap_pg_dir and swapper_pg_dir addresses
+ mov x27, lr
+
+ /*
+ * Invalidate the idmap and swapper page tables to avoid potential
+ * dirty cache lines being evicted.
+ */
+ mov x0, x25
+ add x1, x26, #SWAPPER_DIR_SIZE
+ bl __inval_cache_range
/*
* Clear the idmap and swapper page tables.
@@ -435,9 +442,13 @@ __create_page_tables:
* Create the identity mapping.
*/
add x0, x25, #PAGE_SIZE // section table address
- adr x3, __turn_mmu_on // virtual/physical address
+ ldr x3, =KERNEL_START
+ add x3, x3, x28 // __pa(KERNEL_START)
create_pgd_entry x25, x0, x3, x5, x6
- create_block_map x0, x7, x3, x5, x5, idmap=1
+ ldr x6, =KERNEL_END
+ mov x5, x3 // __pa(KERNEL_START)
+ add x6, x6, x28 // __pa(KERNEL_END)
+ create_block_map x0, x7, x3, x5, x6
/*
* Map the kernel image (starting with PHYS_OFFSET).
@@ -445,7 +456,7 @@ __create_page_tables:
add x0, x26, #PAGE_SIZE // section table address
mov x5, #PAGE_OFFSET
create_pgd_entry x26, x0, x5, x3, x6
- ldr x6, =KERNEL_END - 1
+ ldr x6, =KERNEL_END
mov x3, x24 // phys offset
create_block_map x0, x7, x3, x5, x6
@@ -465,15 +476,23 @@ __create_page_tables:
sub x6, x6, #1 // inclusive range
create_block_map x0, x7, x3, x5, x6
1:
-#ifdef CONFIG_EARLY_PRINTK
/*
- * Create the pgd entry for the UART mapping. The full mapping is done
- * later based earlyprintk kernel parameter.
+ * Create the pgd entry for the fixed mappings.
*/
- ldr x5, =EARLYCON_IOBASE // UART virtual address
+ ldr x5, =FIXADDR_TOP // Fixed mapping virtual address
add x0, x26, #2 * PAGE_SIZE // section table address
create_pgd_entry x26, x0, x5, x6, x7
-#endif
+
+ /*
+ * Since the page tables have been populated with non-cacheable
+ * accesses (MMU disabled), invalidate the idmap and swapper page
+ * tables again to remove any speculatively loaded cache lines.
+ */
+ mov x0, x25
+ add x1, x26, #SWAPPER_DIR_SIZE
+ bl __inval_cache_range
+
+ mov lr, x27
ret
ENDPROC(__create_page_tables)
.ltorg
@@ -482,8 +501,6 @@ ENDPROC(__create_page_tables)
.type __switch_data, %object
__switch_data:
.quad __mmap_switched
- .quad __data_loc // x4
- .quad _data // x5
.quad __bss_start // x6
.quad _end // x7
.quad processor_id // x4
@@ -498,15 +515,7 @@ __switch_data:
__mmap_switched:
adr x3, __switch_data + 8
- ldp x4, x5, [x3], #16
ldp x6, x7, [x3], #16
- cmp x4, x5 // Copy data segment if needed
-1: ccmp x5, x6, #4, ne
- b.eq 2f
- ldr x16, [x4], #8
- str x16, [x5], #8
- b 1b
-2:
1: cmp x6, x7
b.hs 2f
str xzr, [x6], #8 // Clear BSS
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