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-rw-r--r--arch/arm/boot/compressed/head.S493
1 files changed, 267 insertions, 226 deletions
diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S
index ead21e5f2b80..9f406e9c0ea6 100644
--- a/arch/arm/boot/compressed/head.S
+++ b/arch/arm/boot/compressed/head.S
@@ -11,6 +11,12 @@
#include "efi-header.S"
+#ifdef __ARMEB__
+#define OF_DT_MAGIC 0xd00dfeed
+#else
+#define OF_DT_MAGIC 0xedfe0dd0
+#endif
+
AR_CLASS( .arch armv7-a )
M_CLASS( .arch armv7-m )
@@ -28,19 +34,19 @@
#if defined(CONFIG_CPU_V6) || defined(CONFIG_CPU_V6K) || defined(CONFIG_CPU_V7)
.macro loadsp, rb, tmp1, tmp2
.endm
- .macro writeb, ch, rb
+ .macro writeb, ch, rb, tmp
mcr p14, 0, \ch, c0, c5, 0
.endm
#elif defined(CONFIG_CPU_XSCALE)
.macro loadsp, rb, tmp1, tmp2
.endm
- .macro writeb, ch, rb
+ .macro writeb, ch, rb, tmp
mcr p14, 0, \ch, c8, c0, 0
.endm
#else
.macro loadsp, rb, tmp1, tmp2
.endm
- .macro writeb, ch, rb
+ .macro writeb, ch, rb, tmp
mcr p14, 0, \ch, c1, c0, 0
.endm
#endif
@@ -49,18 +55,19 @@
#include CONFIG_DEBUG_LL_INCLUDE
- .macro writeb, ch, rb
+ .macro writeb, ch, rb, tmp
+#ifdef CONFIG_DEBUG_UART_FLOW_CONTROL
+ waituartcts \tmp, \rb
+#endif
+ waituarttxrdy \tmp, \rb
senduart \ch, \rb
+ busyuart \tmp, \rb
.endm
#if defined(CONFIG_ARCH_SA1100)
.macro loadsp, rb, tmp1, tmp2
mov \rb, #0x80000000 @ physical base address
-#ifdef CONFIG_DEBUG_LL_SER3
- add \rb, \rb, #0x00050000 @ Ser3
-#else
add \rb, \rb, #0x00010000 @ Ser1
-#endif
.endm
#else
.macro loadsp, rb, tmp1, tmp2
@@ -81,42 +88,11 @@
bl phex
.endm
- .macro debug_reloc_start
-#ifdef DEBUG
- kputc #'\n'
- kphex r6, 8 /* processor id */
- kputc #':'
- kphex r7, 8 /* architecture id */
-#ifdef CONFIG_CPU_CP15
- kputc #':'
- mrc p15, 0, r0, c1, c0
- kphex r0, 8 /* control reg */
-#endif
- kputc #'\n'
- kphex r5, 8 /* decompressed kernel start */
- kputc #'-'
- kphex r9, 8 /* decompressed kernel end */
- kputc #'>'
- kphex r4, 8 /* kernel execution address */
- kputc #'\n'
-#endif
- .endm
-
- .macro debug_reloc_end
-#ifdef DEBUG
- kphex r5, 8 /* end of kernel */
- kputc #'\n'
- mov r0, r4
- bl memdump /* dump 256 bytes at start of kernel */
-#endif
- .endm
-
/*
* Debug kernel copy by printing the memory addresses involved
*/
.macro dbgkc, begin, end, cbegin, cend
#ifdef DEBUG
- kputc #'\n'
kputc #'C'
kputc #':'
kputc #'0'
@@ -136,7 +112,65 @@
kputc #'x'
kphex \cend, 8 /* End of kernel copy */
kputc #'\n'
- kputc #'\r'
+#endif
+ .endm
+
+ /*
+ * Debug print of the final appended DTB location
+ */
+ .macro dbgadtb, begin, size
+#ifdef DEBUG
+ kputc #'D'
+ kputc #'T'
+ kputc #'B'
+ kputc #':'
+ kputc #'0'
+ kputc #'x'
+ kphex \begin, 8 /* Start of appended DTB */
+ kputc #' '
+ kputc #'('
+ kputc #'0'
+ kputc #'x'
+ kphex \size, 8 /* Size of appended DTB */
+ kputc #')'
+ kputc #'\n'
+#endif
+ .endm
+
+ .macro enable_cp15_barriers, reg
+ mrc p15, 0, \reg, c1, c0, 0 @ read SCTLR
+ tst \reg, #(1 << 5) @ CP15BEN bit set?
+ bne .L_\@
+ orr \reg, \reg, #(1 << 5) @ CP15 barrier instructions
+ mcr p15, 0, \reg, c1, c0, 0 @ write SCTLR
+ ARM( .inst 0xf57ff06f @ v7+ isb )
+ THUMB( isb )
+.L_\@:
+ .endm
+
+ /*
+ * The kernel build system appends the size of the
+ * decompressed kernel at the end of the compressed data
+ * in little-endian form.
+ */
+ .macro get_inflated_image_size, res:req, tmp1:req, tmp2:req
+ adr \res, .Linflated_image_size_offset
+ ldr \tmp1, [\res]
+ add \tmp1, \tmp1, \res @ address of inflated image size
+
+ ldrb \res, [\tmp1] @ get_unaligned_le32
+ ldrb \tmp2, [\tmp1, #1]
+ orr \res, \res, \tmp2, lsl #8
+ ldrb \tmp2, [\tmp1, #2]
+ ldrb \tmp1, [\tmp1, #3]
+ orr \res, \res, \tmp2, lsl #16
+ orr \res, \res, \tmp1, lsl #24
+ .endm
+
+ .macro be32tocpu, val, tmp
+#ifndef __ARMEB__
+ /* convert to little endian */
+ rev_l \val, \tmp
#endif
.endm
@@ -165,7 +199,8 @@ start:
* were patching the initial instructions of the kernel, i.e
* had started to exploit this "patch area".
*/
- .rept 7
+ __initial_nops
+ .rept 5
__nop
.endr
#ifndef CONFIG_THUMB2_KERNEL
@@ -241,10 +276,40 @@ not_angel:
* are already placing their zImage in (eg) the top 64MB
* of this range.
*/
- mov r4, pc
- and r4, r4, #0xf8000000
+ mov r0, pc
+ and r0, r0, #0xf8000000
+#ifdef CONFIG_USE_OF
+ adr r1, LC1
+#ifdef CONFIG_ARM_APPENDED_DTB
+ /*
+ * Look for an appended DTB. If found, we cannot use it to
+ * validate the calculated start of physical memory, as its
+ * memory nodes may need to be augmented by ATAGS stored at
+ * an offset from the same start of physical memory.
+ */
+ ldr r2, [r1, #4] @ get &_edata
+ add r2, r2, r1 @ relocate it
+ ldr r2, [r2] @ get DTB signature
+ ldr r3, =OF_DT_MAGIC
+ cmp r2, r3 @ do we have a DTB there?
+ beq 1f @ if yes, skip validation
+#endif /* CONFIG_ARM_APPENDED_DTB */
+
+ /*
+ * Make sure we have some stack before calling C code.
+ * No GOT fixup has occurred yet, but none of the code we're
+ * about to call uses any global variables.
+ */
+ ldr sp, [r1] @ get stack location
+ add sp, sp, r1 @ apply relocation
+
+ /* Validate calculated start against passed DTB */
+ mov r1, r8
+ bl fdt_check_mem_start
+1:
+#endif /* CONFIG_USE_OF */
/* Determine final kernel image address. */
- add r4, r4, #TEXT_OFFSET
+ add r4, r0, #TEXT_OFFSET
#else
ldr r4, =zreladdr
#endif
@@ -257,41 +322,23 @@ not_angel:
*/
mov r0, pc
cmp r0, r4
- ldrcc r0, LC0+32
+ ldrcc r0, .Lheadroom
addcc r0, r0, pc
cmpcc r4, r0
orrcc r4, r4, #1 @ remember we skipped cache_on
blcs cache_on
-restart: adr r0, LC0
- ldmia r0, {r1, r2, r3, r6, r10, r11, r12}
- ldr sp, [r0, #28]
+restart: adr r0, LC1
+ ldr sp, [r0]
+ ldr r6, [r0, #4]
+ add sp, sp, r0
+ add r6, r6, r0
- /*
- * We might be running at a different address. We need
- * to fix up various pointers.
- */
- sub r0, r0, r1 @ calculate the delta offset
- add r6, r6, r0 @ _edata
- add r10, r10, r0 @ inflated kernel size location
-
- /*
- * The kernel build system appends the size of the
- * decompressed kernel at the end of the compressed data
- * in little-endian form.
- */
- ldrb r9, [r10, #0]
- ldrb lr, [r10, #1]
- orr r9, r9, lr, lsl #8
- ldrb lr, [r10, #2]
- ldrb r10, [r10, #3]
- orr r9, r9, lr, lsl #16
- orr r9, r9, r10, lsl #24
+ get_inflated_image_size r9, r10, lr
#ifndef CONFIG_ZBOOT_ROM
/* malloc space is above the relocated stack (64k max) */
- add sp, sp, r0
- add r10, sp, #0x10000
+ add r10, sp, #MALLOC_SIZE
#else
/*
* With ZBOOT_ROM the bss/stack is non relocatable,
@@ -304,9 +351,6 @@ restart: adr r0, LC0
mov r5, #0 @ init dtb size to 0
#ifdef CONFIG_ARM_APPENDED_DTB
/*
- * r0 = delta
- * r2 = BSS start
- * r3 = BSS end
* r4 = final kernel address (possibly with LSB set)
* r5 = appended dtb size (still unknown)
* r6 = _edata
@@ -314,8 +358,6 @@ restart: adr r0, LC0
* r8 = atags/device tree pointer
* r9 = size of decompressed image
* r10 = end of this image, including bss/stack/malloc space if non XIP
- * r11 = GOT start
- * r12 = GOT end
* sp = stack pointer
*
* if there are device trees (dtb) appended to zImage, advance r10 so that the
@@ -323,11 +365,7 @@ restart: adr r0, LC0
*/
ldr lr, [r6, #0]
-#ifndef __ARMEB__
- ldr r1, =0xedfe0dd0 @ sig is 0xd00dfeed big endian
-#else
- ldr r1, =0xd00dfeed
-#endif
+ ldr r1, =OF_DT_MAGIC
cmp lr, r1
bne dtb_check_done @ not found
@@ -343,13 +381,8 @@ restart: adr r0, LC0
/* Get the initial DTB size */
ldr r5, [r6, #4]
-#ifndef __ARMEB__
- /* convert to little endian */
- eor r1, r5, r5, ror #16
- bic r1, r1, #0x00ff0000
- mov r5, r5, ror #8
- eor r5, r5, r1, lsr #8
-#endif
+ be32tocpu r5, r1
+ dbgadtb r6, r5
/* 50% DTB growth should be good enough */
add r5, r5, r5, lsr #1
/* preserve 64-bit alignment */
@@ -363,7 +396,6 @@ restart: adr r0, LC0
/* temporarily relocate the stack past the DTB work space */
add sp, sp, r5
- stmfd sp!, {r0-r3, ip, lr}
mov r0, r8
mov r1, r6
mov r2, r5
@@ -382,7 +414,6 @@ restart: adr r0, LC0
mov r2, r5
bleq atags_to_fdt
- ldmfd sp!, {r0-r3, ip, lr}
sub sp, sp, r5
#endif
@@ -402,13 +433,7 @@ restart: adr r0, LC0
/* Get the current DTB size */
ldr r5, [r6, #4]
-#ifndef __ARMEB__
- /* convert r5 (dtb size) to little endian */
- eor r1, r5, r5, ror #16
- bic r1, r1, #0x00ff0000
- mov r5, r5, ror #8
- eor r5, r5, r1, lsr #8
-#endif
+ be32tocpu r5, r1
/* preserve 64-bit alignment */
add r5, r5, #7
@@ -467,15 +492,10 @@ dtb_check_done:
/*
* Compute the address of the hyp vectors after relocation.
- * This requires some arithmetic since we cannot directly
- * reference __hyp_stub_vectors in a PC-relative way.
* Call __hyp_set_vectors with the new address so that we
* can HVC again after the copy.
*/
-0: adr r0, 0b
- movw r1, #:lower16:__hyp_stub_vectors - 0b
- movt r1, #:upper16:__hyp_stub_vectors - 0b
- add r0, r0, r1
+ adr_l r0, __hyp_stub_vectors
sub r0, r0, r5
add r0, r0, r10
bl __hyp_set_vectors
@@ -510,11 +530,8 @@ dtb_check_done:
/* Preserve offset to relocated code. */
sub r6, r9, r6
-#ifndef CONFIG_ZBOOT_ROM
- /* cache_clean_flush may use the stack, so relocate it */
- add sp, sp, r6
-#endif
-
+ mov r0, r9 @ start of relocated zImage
+ add r1, sp, r6 @ end of relocated zImage
bl cache_clean_flush
badr r0, restart
@@ -522,6 +539,10 @@ dtb_check_done:
mov pc, r0
wont_overwrite:
+ adr r0, LC0
+ ldmia r0, {r1, r2, r3, r11, r12}
+ sub r0, r0, r1 @ calculate the delta offset
+
/*
* If delta is zero, we are running at the address we were linked at.
* r0 = delta
@@ -608,9 +629,14 @@ not_relocated: mov r0, #0
*/
mov r0, r4
mov r1, sp @ malloc space above stack
- add r2, sp, #0x10000 @ 64k max
+ add r2, sp, #MALLOC_SIZE @ 64k max
mov r3, r7
bl decompress_kernel
+
+ get_inflated_image_size r1, r2, r3
+
+ mov r0, r4 @ start of inflated image
+ add r1, r1, r0 @ end of inflated image
bl cache_clean_flush
bl cache_off
@@ -620,17 +646,11 @@ not_relocated: mov r0, #0
cmp r0, #HYP_MODE @ if not booted in HYP mode...
bne __enter_kernel @ boot kernel directly
- adr r12, .L__hyp_reentry_vectors_offset
- ldr r0, [r12]
- add r0, r0, r12
-
+ adr_l r0, __hyp_reentry_vectors
bl __hyp_set_vectors
__HVC(0) @ otherwise bounce to hyp mode
b . @ should never be reached
-
- .align 2
-.L__hyp_reentry_vectors_offset: .long __hyp_reentry_vectors - .
#else
b __enter_kernel
#endif
@@ -640,14 +660,21 @@ not_relocated: mov r0, #0
LC0: .word LC0 @ r1
.word __bss_start @ r2
.word _end @ r3
- .word _edata @ r6
- .word input_data_end - 4 @ r10 (inflated size location)
.word _got_start @ r11
.word _got_end @ ip
- .word .L_user_stack_end @ sp
- .word _end - restart + 16384 + 1024*1024
.size LC0, . - LC0
+ .type LC1, #object
+LC1: .word .L_user_stack_end - LC1 @ sp
+ .word _edata - LC1 @ r6
+ .size LC1, . - LC1
+
+.Lheadroom:
+ .word _end - restart + 16384 + 1024*1024
+
+.Linflated_image_size_offset:
+ .long (input_data_end - 4) - .
+
#ifdef CONFIG_ARCH_RPC
.globl params
params: ldr r0, =0x10000100 @ params_phys for RPC
@@ -657,6 +684,24 @@ params: ldr r0, =0x10000100 @ params_phys for RPC
#endif
/*
+ * dcache_line_size - get the minimum D-cache line size from the CTR register
+ * on ARMv7.
+ */
+ .macro dcache_line_size, reg, tmp
+#ifdef CONFIG_CPU_V7M
+ movw \tmp, #:lower16:BASEADDR_V7M_SCB + V7M_SCB_CTR
+ movt \tmp, #:upper16:BASEADDR_V7M_SCB + V7M_SCB_CTR
+ ldr \tmp, [\tmp]
+#else
+ mrc p15, 0, \tmp, c0, c0, 1 @ read ctr
+#endif
+ lsr \tmp, \tmp, #16
+ and \tmp, \tmp, #0xf @ cache line size encoding
+ mov \reg, #4 @ bytes per word
+ mov \reg, \reg, lsl \tmp @ actual cache line size
+ .endm
+
+/*
* Turn on the cache. We need to setup some page tables so that we
* can have both the I and D caches on.
*
@@ -820,6 +865,7 @@ __armv4_mmu_cache_on:
mov pc, r12
__armv7_mmu_cache_on:
+ enable_cp15_barriers r11
mov r12, lr
#ifdef CONFIG_MMU
mrc p15, 0, r11, c0, c1, 4 @ read ID_MMFR0
@@ -1142,13 +1188,11 @@ __armv4_mmu_cache_off:
__armv7_mmu_cache_off:
mrc p15, 0, r0, c1, c0
#ifdef CONFIG_MMU
- bic r0, r0, #0x000d
+ bic r0, r0, #0x0005
#else
- bic r0, r0, #0x000c
+ bic r0, r0, #0x0004
#endif
mcr p15, 0, r0, c1, c0 @ turn MMU and cache off
- mov r12, lr
- bl __armv7_mmu_cache_flush
mov r0, #0
#ifdef CONFIG_MMU
mcr p15, 0, r0, c8, c7, 0 @ invalidate whole TLB
@@ -1156,11 +1200,14 @@ __armv7_mmu_cache_off:
mcr p15, 0, r0, c7, c5, 6 @ invalidate BTC
mcr p15, 0, r0, c7, c10, 4 @ DSB
mcr p15, 0, r0, c7, c5, 4 @ ISB
- mov pc, r12
+ mov pc, lr
/*
* Clean and flush the cache to maintain consistency.
*
+ * On entry,
+ * r0 = start address
+ * r1 = end address (exclusive)
* On exit,
* r1, r2, r3, r9, r10, r11, r12 corrupted
* This routine must preserve:
@@ -1169,6 +1216,7 @@ __armv7_mmu_cache_off:
.align 5
cache_clean_flush:
mov r3, #16
+ mov r11, r1
b call_cache_fn
__armv4_mpu_cache_flush:
@@ -1209,6 +1257,7 @@ __armv6_mmu_cache_flush:
mov pc, lr
__armv7_mmu_cache_flush:
+ enable_cp15_barriers r10
tst r4, #1
bne iflush
mrc p15, 0, r10, c0, c1, 5 @ read ID_MMFR1
@@ -1218,51 +1267,16 @@ __armv7_mmu_cache_flush:
mcr p15, 0, r10, c7, c14, 0 @ clean+invalidate D
b iflush
hierarchical:
- mcr p15, 0, r10, c7, c10, 5 @ DMB
- stmfd sp!, {r0-r7, r9-r11}
- mrc p15, 1, r0, c0, c0, 1 @ read clidr
- ands r3, r0, #0x7000000 @ extract loc from clidr
- mov r3, r3, lsr #23 @ left align loc bit field
- beq finished @ if loc is 0, then no need to clean
- mov r10, #0 @ start clean at cache level 0
-loop1:
- add r2, r10, r10, lsr #1 @ work out 3x current cache level
- mov r1, r0, lsr r2 @ extract cache type bits from clidr
- and r1, r1, #7 @ mask of the bits for current cache only
- cmp r1, #2 @ see what cache we have at this level
- blt skip @ skip if no cache, or just i-cache
- mcr p15, 2, r10, c0, c0, 0 @ select current cache level in cssr
- mcr p15, 0, r10, c7, c5, 4 @ isb to sych the new cssr&csidr
- mrc p15, 1, r1, c0, c0, 0 @ read the new csidr
- and r2, r1, #7 @ extract the length of the cache lines
- add r2, r2, #4 @ add 4 (line length offset)
- ldr r4, =0x3ff
- ands r4, r4, r1, lsr #3 @ find maximum number on the way size
- clz r5, r4 @ find bit position of way size increment
- ldr r7, =0x7fff
- ands r7, r7, r1, lsr #13 @ extract max number of the index size
-loop2:
- mov r9, r4 @ create working copy of max way size
-loop3:
- ARM( orr r11, r10, r9, lsl r5 ) @ factor way and cache number into r11
- ARM( orr r11, r11, r7, lsl r2 ) @ factor index number into r11
- THUMB( lsl r6, r9, r5 )
- THUMB( orr r11, r10, r6 ) @ factor way and cache number into r11
- THUMB( lsl r6, r7, r2 )
- THUMB( orr r11, r11, r6 ) @ factor index number into r11
- mcr p15, 0, r11, c7, c14, 2 @ clean & invalidate by set/way
- subs r9, r9, #1 @ decrement the way
- bge loop3
- subs r7, r7, #1 @ decrement the index
- bge loop2
-skip:
- add r10, r10, #2 @ increment cache number
- cmp r3, r10
- bgt loop1
-finished:
- ldmfd sp!, {r0-r7, r9-r11}
- mov r10, #0 @ switch back to cache level 0
- mcr p15, 2, r10, c0, c0, 0 @ select current cache level in cssr
+ dcache_line_size r1, r2 @ r1 := dcache min line size
+ sub r2, r1, #1 @ r2 := line size mask
+ bic r0, r0, r2 @ round down start to line size
+ sub r11, r11, #1 @ end address is exclusive
+ bic r11, r11, r2 @ round down end to line size
+0: cmp r0, r11 @ finished?
+ bgt iflush
+ mcr p15, 0, r0, c7, c14, 1 @ Dcache clean/invalidate by VA
+ add r0, r0, r1
+ b 0b
iflush:
mcr p15, 0, r10, c7, c10, 4 @ DSB
mcr p15, 0, r10, c7, c5, 0 @ invalidate I+BTB
@@ -1351,7 +1365,7 @@ puts: loadsp r3, r2, r1
1: ldrb r2, [r0], #1
teq r2, #0
moveq pc, lr
-2: writeb r2, r3
+2: writeb r2, r3, r1
mov r1, #0x00020000
3: subs r1, r1, #1
bne 3b
@@ -1405,7 +1419,11 @@ memdump: mov r12, r0
__hyp_reentry_vectors:
W(b) . @ reset
W(b) . @ undef
+#ifdef CONFIG_EFI_STUB
+ W(b) __enter_kernel_from_hyp @ hvc from HYP
+#else
W(b) . @ svc
+#endif
W(b) . @ pabort
W(b) . @ dabort
W(b) __enter_kernel @ hyp
@@ -1424,64 +1442,87 @@ __enter_kernel:
reloc_code_end:
#ifdef CONFIG_EFI_STUB
- .align 2
-_start: .long start - .
-
-ENTRY(efi_stub_entry)
- @ allocate space on stack for passing current zImage address
- @ and for the EFI stub to return of new entry point of
- @ zImage, as EFI stub may copy the kernel. Pointer address
- @ is passed in r2. r0 and r1 are passed through from the
- @ EFI firmware to efi_entry
- adr ip, _start
- ldr r3, [ip]
- add r3, r3, ip
- stmfd sp!, {r3, lr}
- mov r2, sp @ pass zImage address in r2
- bl efi_entry
-
- @ Check for error return from EFI stub. r0 has FDT address
- @ or error code.
- cmn r0, #1
- beq efi_load_fail
-
- @ Preserve return value of efi_entry() in r4
- mov r4, r0
-
- @ our cache maintenance code relies on CP15 barrier instructions
- @ but since we arrived here with the MMU and caches configured
- @ by UEFI, we must check that the CP15BEN bit is set in SCTLR.
- @ Note that this bit is RAO/WI on v6 and earlier, so the ISB in
- @ the enable path will be executed on v7+ only.
- mrc p15, 0, r1, c1, c0, 0 @ read SCTLR
- tst r1, #(1 << 5) @ CP15BEN bit set?
- bne 0f
- orr r1, r1, #(1 << 5) @ CP15 barrier instructions
- mcr p15, 0, r1, c1, c0, 0 @ write SCTLR
- ARM( .inst 0xf57ff06f @ v7+ isb )
- THUMB( isb )
+__enter_kernel_from_hyp:
+ mrc p15, 4, r0, c1, c0, 0 @ read HSCTLR
+ bic r0, r0, #0x5 @ disable MMU and caches
+ mcr p15, 4, r0, c1, c0, 0 @ write HSCTLR
+ isb
+ b __enter_kernel
-0: bl cache_clean_flush
- bl cache_off
+ENTRY(efi_enter_kernel)
+ mov r4, r0 @ preserve image base
+ mov r8, r1 @ preserve DT pointer
- @ Set parameters for booting zImage according to boot protocol
- @ put FDT address in r2, it was returned by efi_entry()
- @ r1 is the machine type, and r0 needs to be 0
- mov r0, #0
- mov r1, #0xFFFFFFFF
- mov r2, r4
-
- @ Branch to (possibly) relocated zImage that is in [sp]
- ldr lr, [sp]
- ldr ip, =start_offset
- add lr, lr, ip
- mov pc, lr @ no mode switch
-
-efi_load_fail:
- @ Return EFI_LOAD_ERROR to EFI firmware on error.
- ldr r0, =0x80000001
- ldmfd sp!, {ip, pc}
-ENDPROC(efi_stub_entry)
+ adr_l r0, call_cache_fn
+ adr r1, 0f @ clean the region of code we
+ bl cache_clean_flush @ may run with the MMU off
+
+#ifdef CONFIG_ARM_VIRT_EXT
+ @
+ @ The EFI spec does not support booting on ARM in HYP mode,
+ @ since it mandates that the MMU and caches are on, with all
+ @ 32-bit addressable DRAM mapped 1:1 using short descriptors.
+ @
+ @ While the EDK2 reference implementation adheres to this,
+ @ U-Boot might decide to enter the EFI stub in HYP mode
+ @ anyway, with the MMU and caches either on or off.
+ @
+ mrs r0, cpsr @ get the current mode
+ msr spsr_cxsf, r0 @ record boot mode
+ and r0, r0, #MODE_MASK @ are we running in HYP mode?
+ cmp r0, #HYP_MODE
+ bne .Lefi_svc
+
+ mrc p15, 4, r1, c1, c0, 0 @ read HSCTLR
+ tst r1, #0x1 @ MMU enabled at HYP?
+ beq 1f
+
+ @
+ @ When running in HYP mode with the caches on, we're better
+ @ off just carrying on using the cached 1:1 mapping that the
+ @ firmware provided. Set up the HYP vectors so HVC instructions
+ @ issued from HYP mode take us to the correct handler code. We
+ @ will disable the MMU before jumping to the kernel proper.
+ @
+ ARM( bic r1, r1, #(1 << 30) ) @ clear HSCTLR.TE
+ THUMB( orr r1, r1, #(1 << 30) ) @ set HSCTLR.TE
+ mcr p15, 4, r1, c1, c0, 0
+ adr r0, __hyp_reentry_vectors
+ mcr p15, 4, r0, c12, c0, 0 @ set HYP vector base (HVBAR)
+ isb
+ b .Lefi_hyp
+
+ @
+ @ When running in HYP mode with the caches off, we need to drop
+ @ into SVC mode now, and let the decompressor set up its cached
+ @ 1:1 mapping as usual.
+ @
+1: mov r9, r4 @ preserve image base
+ bl __hyp_stub_install @ install HYP stub vectors
+ safe_svcmode_maskall r1 @ drop to SVC mode
+ msr spsr_cxsf, r0 @ record boot mode
+ orr r4, r9, #1 @ restore image base and set LSB
+ b .Lefi_hyp
+.Lefi_svc:
+#endif
+ mrc p15, 0, r0, c1, c0, 0 @ read SCTLR
+ tst r0, #0x1 @ MMU enabled?
+ orreq r4, r4, #1 @ set LSB if not
+
+.Lefi_hyp:
+ mov r0, r8 @ DT start
+ add r1, r8, r2 @ DT end
+ bl cache_clean_flush
+
+ adr r0, 0f @ switch to our stack
+ ldr sp, [r0]
+ add sp, sp, r0
+
+ mov r5, #0 @ appended DTB size
+ mov r7, #0xFFFFFFFF @ machine ID
+ b wont_overwrite
+ENDPROC(efi_enter_kernel)
+0: .long .L_user_stack_end - .
#endif
.align