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-rw-r--r--arch/arm64/kernel/head.S525
1 files changed, 225 insertions, 300 deletions
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index 6a98f1a38c29..cefe6a73ee54 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -37,8 +37,6 @@
#include "efi-header.S"
-#define __PHYS_OFFSET KERNEL_START
-
#if (PAGE_OFFSET & 0x1fffff) != 0
#error PAGE_OFFSET must be at least 2MB aligned
#endif
@@ -51,9 +49,6 @@
* MMU = off, D-cache = off, I-cache = on or off,
* x0 = physical address to the FDT blob.
*
- * This code is mostly position independent so you call this at
- * __pa(PAGE_OFFSET).
- *
* Note that the callee-saved registers are used for storing variables
* that are useful before the MMU is enabled. The allocations are described
* in the entry routines.
@@ -82,25 +77,34 @@
* primary lowlevel boot path:
*
* Register Scope Purpose
+ * x20 primary_entry() .. __primary_switch() CPU boot mode
* x21 primary_entry() .. start_kernel() FDT pointer passed at boot in x0
+ * x22 create_idmap() .. start_kernel() ID map VA of the DT blob
* x23 primary_entry() .. start_kernel() physical misalignment/KASLR offset
- * x28 __create_page_tables() callee preserved temp register
- * x19/x20 __primary_switch() callee preserved temp registers
- * x24 __primary_switch() .. relocate_kernel() current RELR displacement
+ * x24 __primary_switch() linear map KASLR seed
+ * x25 primary_entry() .. start_kernel() supported VA size
+ * x28 create_idmap() callee preserved temp register
*/
SYM_CODE_START(primary_entry)
bl preserve_boot_args
bl init_kernel_el // w0=cpu_boot_mode
- adrp x23, __PHYS_OFFSET
- and x23, x23, MIN_KIMG_ALIGN - 1 // KASLR offset, defaults to 0
- bl set_cpu_boot_mode_flag
- bl __create_page_tables
+ mov x20, x0
+ bl create_idmap
+
/*
* The following calls CPU setup code, see arch/arm64/mm/proc.S for
* details.
* On return, the CPU will be ready for the MMU to be turned on and
* the TCR will have been set.
*/
+#if VA_BITS > 48
+ mrs_s x0, SYS_ID_AA64MMFR2_EL1
+ tst x0, #0xf << ID_AA64MMFR2_LVA_SHIFT
+ mov x0, #VA_BITS
+ mov x25, #VA_BITS_MIN
+ csel x25, x25, x0, eq
+ mov x0, x25
+#endif
bl __cpu_setup // initialise processor
b __primary_switch
SYM_CODE_END(primary_entry)
@@ -122,28 +126,16 @@ SYM_CODE_START_LOCAL(preserve_boot_args)
b dcache_inval_poc // tail call
SYM_CODE_END(preserve_boot_args)
-/*
- * Macro to create a table entry to the next page.
- *
- * tbl: page table address
- * virt: virtual address
- * shift: #imm page table shift
- * ptrs: #imm pointers per table page
- *
- * Preserves: virt
- * Corrupts: ptrs, tmp1, tmp2
- * Returns: tbl -> next level table page address
- */
- .macro create_table_entry, tbl, virt, shift, ptrs, tmp1, tmp2
- add \tmp1, \tbl, #PAGE_SIZE
- phys_to_pte \tmp2, \tmp1
- 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
+SYM_FUNC_START_LOCAL(clear_page_tables)
+ /*
+ * Clear the init page tables.
+ */
+ adrp x0, init_pg_dir
+ adrp x1, init_pg_end
+ sub x2, x1, x0
+ mov x1, xzr
+ b __pi_memset // tail call
+SYM_FUNC_END(clear_page_tables)
/*
* Macro to populate page table entries, these entries can be pointers to the next level
@@ -179,31 +171,20 @@ SYM_CODE_END(preserve_boot_args)
* vstart: virtual address of start of range
* vend: virtual address of end of range - we map [vstart, vend]
* shift: shift used to transform virtual address into index
- * ptrs: number of entries in page table
+ * order: #imm 2log(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
+ * Preserves: vstart, vend
* 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 * ptrs
- // our entries span multiple tables
-
- lsr \istart, \vstart, \shift
- mov \count, \ptrs
- sub \count, \count, #1
- and \istart, \istart, \count
-
+ .macro compute_indices, vstart, vend, shift, order, istart, iend, count
+ ubfx \istart, \vstart, \shift, \order
+ ubfx \iend, \vend, \shift, \order
+ add \iend, \iend, \count, lsl \order
sub \count, \iend, \istart
.endm
@@ -218,119 +199,116 @@ SYM_CODE_END(preserve_boot_args)
* vend: virtual address of end of range - we map [vstart, vend - 1]
* 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
+ * order: #imm 2log(number of entries in PGD table)
+ *
+ * If extra_shift is set, an extra level will be populated if the end address does
+ * not fit in 'extra_shift' bits. This assumes vend is in the TTBR0 range.
*
* Temporaries: istart, iend, tmp, count, sv - these need to be different registers
* Preserves: vstart, flags
* Corrupts: tbl, rtbl, vend, istart, iend, tmp, count, sv
*/
- .macro map_memory, tbl, rtbl, vstart, vend, flags, phys, pgds, istart, iend, tmp, count, sv
+ .macro map_memory, tbl, rtbl, vstart, vend, flags, phys, order, istart, iend, tmp, count, sv, extra_shift
sub \vend, \vend, #1
add \rtbl, \tbl, #PAGE_SIZE
- mov \sv, \rtbl
mov \count, #0
- compute_indices \vstart, \vend, #PGDIR_SHIFT, \pgds, \istart, \iend, \count
+
+ .ifnb \extra_shift
+ tst \vend, #~((1 << (\extra_shift)) - 1)
+ b.eq .L_\@
+ compute_indices \vstart, \vend, #\extra_shift, #(PAGE_SHIFT - 3), \istart, \iend, \count
+ mov \sv, \rtbl
populate_entries \tbl, \rtbl, \istart, \iend, #PMD_TYPE_TABLE, #PAGE_SIZE, \tmp
mov \tbl, \sv
+ .endif
+.L_\@:
+ compute_indices \vstart, \vend, #PGDIR_SHIFT, #\order, \istart, \iend, \count
mov \sv, \rtbl
+ populate_entries \tbl, \rtbl, \istart, \iend, #PMD_TYPE_TABLE, #PAGE_SIZE, \tmp
+ mov \tbl, \sv
#if SWAPPER_PGTABLE_LEVELS > 3
- compute_indices \vstart, \vend, #PUD_SHIFT, #PTRS_PER_PUD, \istart, \iend, \count
+ compute_indices \vstart, \vend, #PUD_SHIFT, #(PAGE_SHIFT - 3), \istart, \iend, \count
+ mov \sv, \rtbl
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
+ compute_indices \vstart, \vend, #SWAPPER_TABLE_SHIFT, #(PAGE_SHIFT - 3), \istart, \iend, \count
+ mov \sv, \rtbl
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
+ compute_indices \vstart, \vend, #SWAPPER_BLOCK_SHIFT, #(PAGE_SHIFT - 3), \istart, \iend, \count
+ bic \rtbl, \phys, #SWAPPER_BLOCK_SIZE - 1
+ populate_entries \tbl, \rtbl, \istart, \iend, \flags, #SWAPPER_BLOCK_SIZE, \tmp
.endm
/*
- * Setup the initial page tables. We only setup the barest amount which is
- * required to get the kernel running. The following sections are required:
- * - 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
+ * Remap a subregion created with the map_memory macro with modified attributes
+ * or output address. The entire remapped region must have been covered in the
+ * invocation of map_memory.
+ *
+ * x0: last level table address (returned in first argument to map_memory)
+ * x1: start VA of the existing mapping
+ * x2: start VA of the region to update
+ * x3: end VA of the region to update (exclusive)
+ * x4: start PA associated with the region to update
+ * x5: attributes to set on the updated region
+ * x6: order of the last level mappings
*/
-SYM_FUNC_START_LOCAL(__create_page_tables)
- mov x28, lr
+SYM_FUNC_START_LOCAL(remap_region)
+ sub x3, x3, #1 // make end inclusive
- /*
- * Invalidate the init page tables to avoid potential dirty cache lines
- * being evicted. Other page tables are allocated in rodata as part of
- * the kernel image, and thus are clean to the PoC per the boot
- * protocol.
- */
- adrp x0, init_pg_dir
- adrp x1, init_pg_end
- bl dcache_inval_poc
+ // Get the index offset for the start of the last level table
+ lsr x1, x1, x6
+ bfi x1, xzr, #0, #PAGE_SHIFT - 3
- /*
- * Clear the init page tables.
- */
- adrp x0, init_pg_dir
- adrp x1, init_pg_end
- sub x1, x1, x0
-1: stp xzr, xzr, [x0], #16
- stp xzr, xzr, [x0], #16
- stp xzr, xzr, [x0], #16
- stp xzr, xzr, [x0], #16
- subs x1, x1, #64
- b.ne 1b
+ // Derive the start and end indexes into the last level table
+ // associated with the provided region
+ lsr x2, x2, x6
+ lsr x3, x3, x6
+ sub x2, x2, x1
+ sub x3, x3, x1
- mov x7, SWAPPER_MM_MMUFLAGS
+ mov x1, #1
+ lsl x6, x1, x6 // block size at this level
- /*
- * Create the identity mapping.
- */
- adrp x0, idmap_pg_dir
- adrp x3, __idmap_text_start // __pa(__idmap_text_start)
-
-#ifdef CONFIG_ARM64_VA_BITS_52
- mrs_s x6, SYS_ID_AA64MMFR2_EL1
- and x6, x6, #(0xf << ID_AA64MMFR2_LVA_SHIFT)
- mov x5, #52
- cbnz x6, 1f
-#endif
- mov x5, #VA_BITS_MIN
-1:
- adr_l x6, vabits_actual
- str x5, [x6]
- dmb sy
- dc ivac, x6 // Invalidate potentially stale cache line
+ populate_entries x0, x4, x2, x3, x5, x6, x7
+ ret
+SYM_FUNC_END(remap_region)
+SYM_FUNC_START_LOCAL(create_idmap)
+ mov x28, lr
/*
- * 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.
+ * The ID map carries a 1:1 mapping of the physical address range
+ * covered by the loaded image, which could be anywhere in DRAM. This
+ * means that the required size of the VA (== PA) space is decided at
+ * boot time, and could be more than the configured size of the VA
+ * space for ordinary kernel and user space mappings.
+ *
+ * There are three cases to consider here:
+ * - 39 <= VA_BITS < 48, and the ID map needs up to 48 VA bits to cover
+ * the placement of the image. In this case, we configure one extra
+ * level of translation on the fly for the ID map only. (This case
+ * also covers 42-bit VA/52-bit PA on 64k pages).
*
- * 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 __idmap_text_end.
+ * - VA_BITS == 48, and the ID map needs more than 48 VA bits. This can
+ * only happen when using 64k pages, in which case we need to extend
+ * the root level table rather than add a level. Note that we can
+ * treat this case as 'always extended' as long as we take care not
+ * to program an unsupported T0SZ value into the TCR register.
+ *
+ * - Combinations that would require two additional levels of
+ * translation are not supported, e.g., VA_BITS==36 on 16k pages, or
+ * VA_BITS==39/4k pages with 5-level paging, where the input address
+ * requires more than 47 or 48 bits, respectively.
*/
- adrp x5, __idmap_text_end
- clz x5, x5
- cmp x5, TCR_T0SZ(VA_BITS_MIN) // default T0SZ small enough?
- 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
-
#if (VA_BITS < 48)
+#define IDMAP_PGD_ORDER (VA_BITS - PGDIR_SHIFT)
#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.
@@ -342,36 +320,40 @@ SYM_FUNC_START_LOCAL(__create_page_tables)
#if VA_BITS != EXTRA_SHIFT
#error "Mismatch between VA_BITS and page size/number of translation levels"
#endif
-
- mov x4, EXTRA_PTRS
- create_table_entry x0, x3, EXTRA_SHIFT, x4, x5, x6
#else
+#define IDMAP_PGD_ORDER (PHYS_MASK_SHIFT - PGDIR_SHIFT)
+#define EXTRA_SHIFT
/*
* 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
- adr_l x6, __idmap_text_end // __pa(__idmap_text_end)
-
- map_memory x0, x1, x3, x6, x7, x3, x4, x10, x11, x12, x13, x14
-
- /*
- * Map the kernel image (starting with PHYS_OFFSET).
- */
- adrp x0, init_pg_dir
- mov_q x5, KIMAGE_VADDR // compile time __va(_text)
- add x5, x5, x23 // add KASLR displacement
- 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)
-
- map_memory x0, x1, x5, x6, x7, x3, x4, x10, x11, x12, x13, x14
+ adrp x0, init_idmap_pg_dir
+ adrp x3, _text
+ adrp x6, _end + MAX_FDT_SIZE + SWAPPER_BLOCK_SIZE
+ mov x7, SWAPPER_RX_MMUFLAGS
+
+ map_memory x0, x1, x3, x6, x7, x3, IDMAP_PGD_ORDER, x10, x11, x12, x13, x14, EXTRA_SHIFT
+
+ /* Remap the kernel page tables r/w in the ID map */
+ adrp x1, _text
+ adrp x2, init_pg_dir
+ adrp x3, init_pg_end
+ bic x4, x2, #SWAPPER_BLOCK_SIZE - 1
+ mov x5, SWAPPER_RW_MMUFLAGS
+ mov x6, #SWAPPER_BLOCK_SHIFT
+ bl remap_region
+
+ /* Remap the FDT after the kernel image */
+ adrp x1, _text
+ adrp x22, _end + SWAPPER_BLOCK_SIZE
+ bic x2, x22, #SWAPPER_BLOCK_SIZE - 1
+ bfi x22, x21, #0, #SWAPPER_BLOCK_SHIFT // remapped FDT address
+ add x3, x2, #MAX_FDT_SIZE + SWAPPER_BLOCK_SIZE
+ bic x4, x21, #SWAPPER_BLOCK_SIZE - 1
+ mov x5, SWAPPER_RW_MMUFLAGS
+ mov x6, #SWAPPER_BLOCK_SHIFT
+ bl remap_region
/*
* Since the page tables have been populated with non-cacheable
@@ -380,16 +362,27 @@ SYM_FUNC_START_LOCAL(__create_page_tables)
*/
dmb sy
- adrp x0, idmap_pg_dir
- adrp x1, idmap_pg_end
+ adrp x0, init_idmap_pg_dir
+ adrp x1, init_idmap_pg_end
bl dcache_inval_poc
+ ret x28
+SYM_FUNC_END(create_idmap)
+SYM_FUNC_START_LOCAL(create_kernel_mapping)
adrp x0, init_pg_dir
- adrp x1, init_pg_end
- bl dcache_inval_poc
+ mov_q x5, KIMAGE_VADDR // compile time __va(_text)
+ add x5, x5, x23 // add KASLR displacement
+ 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)
+ mov x7, SWAPPER_RW_MMUFLAGS
- ret x28
-SYM_FUNC_END(__create_page_tables)
+ map_memory x0, x1, x5, x6, x7, x3, (VA_BITS - PGDIR_SHIFT), x10, x11, x12, x13, x14
+
+ dsb ishst // sync with page table walker
+ ret
+SYM_FUNC_END(create_kernel_mapping)
/*
* Initialize CPU registers with task-specific and cpu-specific context.
@@ -420,7 +413,7 @@ SYM_FUNC_END(__create_page_tables)
/*
* The following fragment of code is executed with the MMU enabled.
*
- * x0 = __PHYS_OFFSET
+ * x0 = __pa(KERNEL_START)
*/
SYM_FUNC_START_LOCAL(__primary_switched)
adr_l x4, init_task
@@ -439,6 +432,9 @@ SYM_FUNC_START_LOCAL(__primary_switched)
sub x4, x4, x0 // the kernel virtual and
str_l x4, kimage_voffset, x5 // physical mappings
+ mov x0, x20
+ bl set_cpu_boot_mode_flag
+
// Clear BSS
adr_l x0, __bss_start
mov x1, xzr
@@ -447,35 +443,30 @@ SYM_FUNC_START_LOCAL(__primary_switched)
bl __pi_memset
dsb ishst // Make zero page visible to PTW
+#if VA_BITS > 48
+ adr_l x8, vabits_actual // Set this early so KASAN early init
+ str x25, [x8] // ... observes the correct value
+ dc civac, x8 // Make visible to booting secondaries
+#endif
+
+#ifdef CONFIG_RANDOMIZE_BASE
+ adrp x5, memstart_offset_seed // Save KASLR linear map seed
+ strh w24, [x5, :lo12:memstart_offset_seed]
+#endif
#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
bl kasan_early_init
#endif
mov x0, x21 // pass FDT address in x0
bl early_fdt_map // Try mapping the FDT early
+ mov x0, x20 // pass the full boot status
bl init_feature_override // Parse cpu feature overrides
-#ifdef CONFIG_RANDOMIZE_BASE
- tst x23, ~(MIN_KIMG_ALIGN - 1) // already running randomized?
- b.ne 0f
- bl kaslr_early_init // parse FDT for KASLR options
- cbz x0, 0f // KASLR disabled? just proceed
- orr x23, x23, x0 // record KASLR offset
- ldp x29, x30, [sp], #16 // we must enable KASLR, return
- ret // to __primary_switch()
-0:
-#endif
- bl switch_to_vhe // Prefer VHE if possible
+ mov x0, x20
+ bl finalise_el2 // Prefer VHE if possible
ldp x29, x30, [sp], #16
bl start_kernel
ASM_BUG()
SYM_FUNC_END(__primary_switched)
- .pushsection ".rodata", "a"
-SYM_DATA_START(kimage_vaddr)
- .quad _text
-SYM_DATA_END(kimage_vaddr)
-EXPORT_SYMBOL(kimage_vaddr)
- .popsection
-
/*
* end early head section, begin head code that is also used for
* hotplug and needs to have the same protections as the text region
@@ -490,8 +481,9 @@ EXPORT_SYMBOL(kimage_vaddr)
* Since we cannot always rely on ERET synchronizing writes to sysregs (e.g. if
* SCTLR_ELx.EOS is clear), we place an ISB prior to ERET.
*
- * Returns either BOOT_CPU_MODE_EL1 or BOOT_CPU_MODE_EL2 in w0 if
- * booted in EL1 or EL2 respectively.
+ * Returns either BOOT_CPU_MODE_EL1 or BOOT_CPU_MODE_EL2 in x0 if
+ * booted in EL1 or EL2 respectively, with the top 32 bits containing
+ * potential context flags. These flags are *not* stored in __boot_cpu_mode.
*/
SYM_FUNC_START(init_kernel_el)
mrs x0, CurrentEL
@@ -520,6 +512,8 @@ SYM_INNER_LABEL(init_el2, SYM_L_LOCAL)
msr vbar_el2, x0
isb
+ mov_q x1, INIT_SCTLR_EL1_MMU_OFF
+
/*
* Fruity CPUs seem to have HCR_EL2.E2H set to RES1,
* making it impossible to start in nVHE mode. Is that
@@ -529,34 +523,19 @@ SYM_INNER_LABEL(init_el2, SYM_L_LOCAL)
and x0, x0, #HCR_E2H
cbz x0, 1f
- /* Switching to VHE requires a sane SCTLR_EL1 as a start */
- mov_q x0, INIT_SCTLR_EL1_MMU_OFF
- msr_s SYS_SCTLR_EL12, x0
-
- /*
- * Force an eret into a helper "function", and let it return
- * to our original caller... This makes sure that we have
- * initialised the basic PSTATE state.
- */
- mov x0, #INIT_PSTATE_EL2
- msr spsr_el1, x0
- adr x0, __cpu_stick_to_vhe
- msr elr_el1, x0
- eret
+ /* Set a sane SCTLR_EL1, the VHE way */
+ msr_s SYS_SCTLR_EL12, x1
+ mov x2, #BOOT_CPU_FLAG_E2H
+ b 2f
1:
- mov_q x0, INIT_SCTLR_EL1_MMU_OFF
- msr sctlr_el1, x0
-
+ msr sctlr_el1, x1
+ mov x2, xzr
+2:
msr elr_el2, lr
mov w0, #BOOT_CPU_MODE_EL2
+ orr x0, x0, x2
eret
-
-__cpu_stick_to_vhe:
- mov x0, #HVC_VHE_RESTART
- hvc #0
- mov x0, #BOOT_CPU_MODE_EL2
- ret
SYM_FUNC_END(init_kernel_el)
/*
@@ -569,52 +548,21 @@ SYM_FUNC_START_LOCAL(set_cpu_boot_mode_flag)
b.ne 1f
add x1, x1, #4
1: str w0, [x1] // Save CPU boot mode
- dmb sy
- dc ivac, x1 // Invalidate potentially stale cache line
ret
SYM_FUNC_END(set_cpu_boot_mode_flag)
-/*
- * These values are written with the MMU off, but read with the MMU on.
- * Writers will invalidate the corresponding address, discarding up to a
- * 'Cache Writeback Granule' (CWG) worth of data. The linker script ensures
- * sufficient alignment that the CWG doesn't overlap another section.
- */
- .pushsection ".mmuoff.data.write", "aw"
-/*
- * We need to find out the CPU boot mode long after boot, so we need to
- * store it in a writable variable.
- *
- * This is not in .bss, because we set it sufficiently early that the boot-time
- * zeroing of .bss would clobber it.
- */
-SYM_DATA_START(__boot_cpu_mode)
- .long BOOT_CPU_MODE_EL2
- .long BOOT_CPU_MODE_EL1
-SYM_DATA_END(__boot_cpu_mode)
-/*
- * The booting CPU updates the failed status @__early_cpu_boot_status,
- * with MMU turned off.
- */
-SYM_DATA_START(__early_cpu_boot_status)
- .quad 0
-SYM_DATA_END(__early_cpu_boot_status)
-
- .popsection
-
/*
* This provides a "holding pen" for platforms to hold all secondary
* cores are held until we're ready for them to initialise.
*/
SYM_FUNC_START(secondary_holding_pen)
bl init_kernel_el // w0=cpu_boot_mode
- bl set_cpu_boot_mode_flag
- mrs x0, mpidr_el1
+ mrs x2, mpidr_el1
mov_q x1, MPIDR_HWID_BITMASK
- and x0, x0, x1
+ and x2, x2, x1
adr_l x3, secondary_holding_pen_release
pen: ldr x4, [x3]
- cmp x4, x0
+ cmp x4, x2
b.eq secondary_startup
wfe
b pen
@@ -626,7 +574,6 @@ SYM_FUNC_END(secondary_holding_pen)
*/
SYM_FUNC_START(secondary_entry)
bl init_kernel_el // w0=cpu_boot_mode
- bl set_cpu_boot_mode_flag
b secondary_startup
SYM_FUNC_END(secondary_entry)
@@ -634,16 +581,24 @@ SYM_FUNC_START_LOCAL(secondary_startup)
/*
* Common entry point for secondary CPUs.
*/
- bl switch_to_vhe
+ mov x20, x0 // preserve boot mode
+ bl finalise_el2
bl __cpu_secondary_check52bitva
+#if VA_BITS > 48
+ ldr_l x0, vabits_actual
+#endif
bl __cpu_setup // initialise processor
adrp x1, swapper_pg_dir
+ adrp x2, idmap_pg_dir
bl __enable_mmu
ldr x8, =__secondary_switched
br x8
SYM_FUNC_END(secondary_startup)
SYM_FUNC_START_LOCAL(__secondary_switched)
+ mov x0, x20
+ bl set_cpu_boot_mode_flag
+ str_l xzr, __early_cpu_boot_status, x3
adr_l x5, vectors
msr vbar_el1, x5
isb
@@ -691,6 +646,7 @@ SYM_FUNC_END(__secondary_too_slow)
*
* x0 = SCTLR_EL1 value for turning on the MMU.
* x1 = TTBR1_EL1 value
+ * x2 = ID map root table address
*
* Returns to the caller via x30/lr. This requires the caller to be covered
* by the .idmap.text section.
@@ -699,20 +655,15 @@ SYM_FUNC_END(__secondary_too_slow)
* If it isn't, park the CPU
*/
SYM_FUNC_START(__enable_mmu)
- mrs x2, ID_AA64MMFR0_EL1
- ubfx x2, x2, #ID_AA64MMFR0_TGRAN_SHIFT, 4
- cmp x2, #ID_AA64MMFR0_TGRAN_SUPPORTED_MIN
+ mrs x3, ID_AA64MMFR0_EL1
+ ubfx x3, x3, #ID_AA64MMFR0_TGRAN_SHIFT, 4
+ cmp x3, #ID_AA64MMFR0_TGRAN_SUPPORTED_MIN
b.lt __no_granule_support
- cmp x2, #ID_AA64MMFR0_TGRAN_SUPPORTED_MAX
+ cmp x3, #ID_AA64MMFR0_TGRAN_SUPPORTED_MAX
b.gt __no_granule_support
- update_early_cpu_boot_status 0, x2, x3
- adrp x2, idmap_pg_dir
- phys_to_ttbr x1, x1
phys_to_ttbr x2, x2
msr ttbr0_el1, x2 // load TTBR0
- offset_ttbr1 x1, x3
- msr ttbr1_el1, x1 // load TTBR1
- isb
+ load_ttbr1 x1, x1, x3
set_sctlr_el1 x0
@@ -720,7 +671,7 @@ SYM_FUNC_START(__enable_mmu)
SYM_FUNC_END(__enable_mmu)
SYM_FUNC_START(__cpu_secondary_check52bitva)
-#ifdef CONFIG_ARM64_VA_BITS_52
+#if VA_BITS > 48
ldr_l x0, vabits_actual
cmp x0, #52
b.ne 2f
@@ -755,13 +706,10 @@ SYM_FUNC_START_LOCAL(__relocate_kernel)
* Iterate over each entry in the relocation table, and apply the
* relocations in place.
*/
- ldr w9, =__rela_offset // offset to reloc table
- ldr w10, =__rela_size // size of reloc table
-
+ adr_l x9, __rela_start
+ adr_l x10, __rela_end
mov_q x11, KIMAGE_VADDR // default virtual offset
add x11, x11, x23 // actual virtual offset
- add x9, x9, x11 // __va(.rela)
- add x10, x9, x10 // __va(.rela) + sizeof(.rela)
0: cmp x9, x10
b.hs 1f
@@ -804,21 +752,9 @@ SYM_FUNC_START_LOCAL(__relocate_kernel)
* entry in x9, the address being relocated by the current address or
* bitmap entry in x13 and the address being relocated by the current
* bit in x14.
- *
- * Because addends are stored in place in the binary, RELR relocations
- * cannot be applied idempotently. We use x24 to keep track of the
- * currently applied displacement so that we can correctly relocate if
- * __relocate_kernel is called twice with non-zero displacements (i.e.
- * if there is both a physical misalignment and a KASLR displacement).
*/
- ldr w9, =__relr_offset // offset to reloc table
- ldr w10, =__relr_size // size of reloc table
- add x9, x9, x11 // __va(.relr)
- add x10, x9, x10 // __va(.relr) + sizeof(.relr)
-
- sub x15, x23, x24 // delta from previous offset
- cbz x15, 7f // nothing to do if unchanged
- mov x24, x23 // save new offset
+ adr_l x9, __relr_start
+ adr_l x10, __relr_end
2: cmp x9, x10
b.hs 7f
@@ -826,7 +762,7 @@ SYM_FUNC_START_LOCAL(__relocate_kernel)
tbnz x11, #0, 3f // branch to handle bitmaps
add x13, x11, x23
ldr x12, [x13] // relocate address entry
- add x12, x12, x15
+ add x12, x12, x23
str x12, [x13], #8 // adjust to start of bitmap
b 2b
@@ -835,7 +771,7 @@ SYM_FUNC_START_LOCAL(__relocate_kernel)
cbz x11, 6f
tbz x11, #0, 5f // skip bit if not set
ldr x12, [x14] // relocate bit
- add x12, x12, x15
+ add x12, x12, x23
str x12, [x14]
5: add x14, x14, #8 // move to next bit's address
@@ -856,43 +792,32 @@ SYM_FUNC_END(__relocate_kernel)
#endif
SYM_FUNC_START_LOCAL(__primary_switch)
+ adrp x1, reserved_pg_dir
+ adrp x2, init_idmap_pg_dir
+ bl __enable_mmu
+#ifdef CONFIG_RELOCATABLE
+ adrp x23, KERNEL_START
+ and x23, x23, MIN_KIMG_ALIGN - 1
#ifdef CONFIG_RANDOMIZE_BASE
- mov x19, x0 // preserve new SCTLR_EL1 value
- mrs x20, sctlr_el1 // preserve old SCTLR_EL1 value
+ mov x0, x22
+ adrp x1, init_pg_end
+ mov sp, x1
+ mov x29, xzr
+ bl __pi_kaslr_early_init
+ and x24, x0, #SZ_2M - 1 // capture memstart offset seed
+ bic x0, x0, #SZ_2M - 1
+ orr x23, x23, x0 // record kernel offset
+#endif
#endif
+ bl clear_page_tables
+ bl create_kernel_mapping
adrp x1, init_pg_dir
- bl __enable_mmu
+ load_ttbr1 x1, x1, x2
#ifdef CONFIG_RELOCATABLE
-#ifdef CONFIG_RELR
- mov x24, #0 // no RELR displacement yet
-#endif
bl __relocate_kernel
-#ifdef CONFIG_RANDOMIZE_BASE
- ldr x8, =__primary_switched
- adrp x0, __PHYS_OFFSET
- blr x8
-
- /*
- * If we return here, we have a KASLR displacement in x23 which we need
- * to take into account by discarding the current kernel mapping and
- * creating a new one.
- */
- pre_disable_mmu_workaround
- msr sctlr_el1, x20 // disable the MMU
- isb
- bl __create_page_tables // recreate kernel mapping
-
- tlbi vmalle1 // Remove any stale TLB entries
- dsb nsh
- isb
-
- set_sctlr_el1 x19 // re-enable the MMU
-
- bl __relocate_kernel
-#endif
#endif
ldr x8, =__primary_switched
- adrp x0, __PHYS_OFFSET
+ adrp x0, KERNEL_START // __pa(KERNEL_START)
br x8
SYM_FUNC_END(__primary_switch)