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-rw-r--r--arch/arm/boot/compressed/head.S224
1 files changed, 141 insertions, 83 deletions
diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S
index c5d60250d43..3a8b32df6b3 100644
--- a/arch/arm/boot/compressed/head.S
+++ b/arch/arm/boot/compressed/head.S
@@ -9,7 +9,9 @@
* published by the Free Software Foundation.
*/
#include <linux/linkage.h>
+#include <asm/assembler.h>
+ .arch armv7-a
/*
* Debugging stuff
*
@@ -43,7 +45,7 @@
#else
-#include <mach/debug-macro.S>
+#include CONFIG_DEBUG_LL_INCLUDE
.macro writeb, ch, rb
senduart \ch, \rb
@@ -58,11 +60,6 @@
add \rb, \rb, #0x00010000 @ Ser1
#endif
.endm
-#elif defined(CONFIG_ARCH_S3C2410)
- .macro loadsp, rb, tmp
- mov \rb, #0x50000000
- add \rb, \rb, #0x4000 * CONFIG_S3C_LOWLEVEL_UART_PORT
- .endm
#else
.macro loadsp, rb, tmp
addruart \rb, \tmp
@@ -132,10 +129,15 @@ start:
.word start @ absolute load/run zImage address
.word _edata @ zImage end address
THUMB( .thumb )
-1: mov r7, r1 @ save architecture ID
+1:
+ ARM_BE8( setend be ) @ go BE8 if compiled for BE8
+ mrs r9, cpsr
+#ifdef CONFIG_ARM_VIRT_EXT
+ bl __hyp_stub_install @ get into SVC mode, reversibly
+#endif
+ mov r7, r1 @ save architecture ID
mov r8, r2 @ save atags pointer
-#ifndef __ARM_ARCH_2__
/*
* Booting from Angel - need to enter SVC mode and disable
* FIQs/IRQs (numeric definitions from angel arm.h source).
@@ -148,13 +150,9 @@ start:
ARM( swi 0x123456 ) @ angel_SWI_ARM
THUMB( svc 0xab ) @ angel_SWI_THUMB
not_angel:
- mrs r2, cpsr @ turn off interrupts to
- orr r2, r2, #0xc0 @ prevent angel from running
- msr cpsr_c, r2
-#else
- teqp pc, #0x0c000003 @ turn off interrupts
-#endif
-
+ safe_svcmode_maskall r0
+ msr spsr_cxsf, r9 @ Save the CPU boot mode in
+ @ SPSR
/*
* Note that some cache flushing and other stuff may
* be needed here - is there an Angel SWI call for this?
@@ -176,7 +174,19 @@ not_angel:
ldr r4, =zreladdr
#endif
- bl cache_on
+ /*
+ * Set up a page table only if it won't overwrite ourself.
+ * That means r4 < pc && r4 - 16k page directory > &_end.
+ * Given that r4 > &_end is most unfrequent, we add a rough
+ * additional 1MB of room for a possible appended DTB.
+ */
+ mov r0, pc
+ cmp r0, r4
+ ldrcc r0, LC0+32
+ 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}
@@ -222,7 +232,7 @@ restart: adr r0, LC0
* r0 = delta
* r2 = BSS start
* r3 = BSS end
- * r4 = final kernel address
+ * r4 = final kernel address (possibly with LSB set)
* r5 = appended dtb size (still unknown)
* r6 = _edata
* r7 = architecture ID
@@ -270,10 +280,11 @@ restart: adr r0, LC0
*/
cmp r0, #1
sub r0, r4, #TEXT_OFFSET
+ bic r0, r0, #1
add r0, r0, #0x100
mov r1, r6
sub r2, sp, r6
- blne atags_to_fdt
+ bleq atags_to_fdt
ldmfd sp!, {r0-r3, ip, lr}
sub sp, sp, #0x10000
@@ -316,12 +327,13 @@ dtb_check_done:
/*
* Check to see if we will overwrite ourselves.
- * r4 = final kernel address
+ * r4 = final kernel address (possibly with LSB set)
* r9 = size of decompressed image
* r10 = end of this image, including bss/stack/malloc space if non XIP
* We basically want:
* r4 - 16k page directory >= r10 -> OK
* r4 + image length <= address of wont_overwrite -> OK
+ * Note: the possible LSB in r4 is harmless here.
*/
add r10, r10, #16384
cmp r4, r10
@@ -350,6 +362,20 @@ dtb_check_done:
adr r5, restart
bic r5, r5, #31
+/* Relocate the hyp vector base if necessary */
+#ifdef CONFIG_ARM_VIRT_EXT
+ mrs r0, spsr
+ and r0, r0, #MODE_MASK
+ cmp r0, #HYP_MODE
+ bne 1f
+
+ bl __hyp_get_vectors
+ sub r0, r0, r5
+ add r0, r0, r10
+ bl __hyp_set_vectors
+1:
+#endif
+
sub r9, r6, r5 @ size to copy
add r9, r9, #31 @ rounded up to a multiple
bic r9, r9, #31 @ ... of 32 bytes
@@ -369,7 +395,8 @@ dtb_check_done:
add sp, sp, r6
#endif
- bl cache_clean_flush
+ tst r4, #1
+ bleq cache_clean_flush
adr r0, BSYM(restart)
add r0, r0, r6
@@ -381,7 +408,7 @@ wont_overwrite:
* r0 = delta
* r2 = BSS start
* r3 = BSS end
- * r4 = kernel execution address
+ * r4 = kernel execution address (possibly with LSB set)
* r5 = appended dtb size (0 if not present)
* r7 = architecture ID
* r8 = atags pointer
@@ -444,6 +471,15 @@ not_relocated: mov r0, #0
cmp r2, r3
blo 1b
+ /*
+ * Did we skip the cache setup earlier?
+ * That is indicated by the LSB in r4.
+ * Do it now if so.
+ */
+ tst r4, #1
+ bic r4, r4, #1
+ blne cache_on
+
/*
* The C runtime environment should now be setup sufficiently.
* Set up some pointers, and start decompressing.
@@ -458,11 +494,29 @@ not_relocated: mov r0, #0
bl decompress_kernel
bl cache_clean_flush
bl cache_off
- mov r0, #0 @ must be zero
mov r1, r7 @ restore architecture number
mov r2, r8 @ restore atags pointer
- ARM( mov pc, r4 ) @ call kernel
- THUMB( bx r4 ) @ entry point is always ARM
+
+#ifdef CONFIG_ARM_VIRT_EXT
+ mrs r0, spsr @ Get saved CPU boot mode
+ and r0, r0, #MODE_MASK
+ 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
+
+ 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
.align 2
.type LC0, #object
@@ -474,6 +528,7 @@ LC0: .word LC0 @ r1
.word _got_start @ r11
.word _got_end @ ip
.word .L_user_stack_end @ sp
+ .word _end - restart + 16384 + 1024*1024
.size LC0, . - LC0
#ifdef CONFIG_ARCH_RPC
@@ -567,6 +622,12 @@ __armv3_mpu_cache_on:
mcr p15, 0, r0, c7, c0, 0 @ invalidate whole cache v3
mov pc, lr
+#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
+#define CB_BITS 0x08
+#else
+#define CB_BITS 0x0c
+#endif
+
__setup_mmu: sub r3, r4, #16384 @ Page directory size
bic r3, r3, #0xff @ Align the pointer
bic r3, r3, #0x3f00
@@ -578,17 +639,14 @@ __setup_mmu: sub r3, r4, #16384 @ Page directory size
mov r9, r0, lsr #18
mov r9, r9, lsl #18 @ start of RAM
add r10, r9, #0x10000000 @ a reasonable RAM size
- mov r1, #0x12
- orr r1, r1, #3 << 10
+ mov r1, #0x12 @ XN|U + section mapping
+ orr r1, r1, #3 << 10 @ AP=11
add r2, r3, #16384
1: cmp r1, r9 @ if virt > start of RAM
-#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
- orrhs r1, r1, #0x08 @ set cacheable
-#else
- orrhs r1, r1, #0x0c @ set cacheable, bufferable
-#endif
- cmp r1, r10 @ if virt > end of RAM
- bichs r1, r1, #0x0c @ clear cacheable, bufferable
+ cmphs r10, r1 @ && end of RAM > virt
+ bic r1, r1, #0x1c @ clear XN|U + C + B
+ orrlo r1, r1, #0x10 @ Set XN|U for non-RAM
+ orrhs r1, r1, r6 @ set RAM section settings
str r1, [r0], #4 @ 1:1 mapping
add r1, r1, #1048576
teq r0, r2
@@ -599,7 +657,7 @@ __setup_mmu: sub r3, r4, #16384 @ Page directory size
* so there is no map overlap problem for up to 1 MB compressed kernel.
* If the execution is in RAM then we would only be duplicating the above.
*/
- mov r1, #0x1e
+ orr r1, r6, #0x04 @ ensure B is set for this
orr r1, r1, #3 << 10
mov r2, pc
mov r2, r2, lsr #20
@@ -611,6 +669,15 @@ __setup_mmu: sub r3, r4, #16384 @ Page directory size
mov pc, lr
ENDPROC(__setup_mmu)
+@ Enable unaligned access on v6, to allow better code generation
+@ for the decompressor C code:
+__armv6_mmu_cache_on:
+ mrc p15, 0, r0, c1, c0, 0 @ read SCTLR
+ bic r0, r0, #2 @ A (no unaligned access fault)
+ orr r0, r0, #1 << 22 @ U (v6 unaligned access model)
+ mcr p15, 0, r0, c1, c0, 0 @ write SCTLR
+ b __armv4_mmu_cache_on
+
__arm926ejs_mmu_cache_on:
#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
mov r0, #4 @ put dcache in WT mode
@@ -620,6 +687,7 @@ __arm926ejs_mmu_cache_on:
__armv4_mmu_cache_on:
mov r12, lr
#ifdef CONFIG_MMU
+ mov r6, #CB_BITS | 0x12 @ U
bl __setup_mmu
mov r0, #0
mcr p15, 0, r0, c7, c10, 4 @ drain write buffer
@@ -627,9 +695,7 @@ __armv4_mmu_cache_on:
mrc p15, 0, r0, c1, c0, 0 @ read control reg
orr r0, r0, #0x5000 @ I-cache enable, RR cache replacement
orr r0, r0, #0x0030
-#ifdef CONFIG_CPU_ENDIAN_BE8
- orr r0, r0, #1 << 25 @ big-endian page tables
-#endif
+ ARM_BE8( orr r0, r0, #1 << 25 ) @ big-endian page tables
bl __common_mmu_cache_on
mov r0, #0
mcr p15, 0, r0, c8, c7, 0 @ flush I,D TLBs
@@ -641,6 +707,7 @@ __armv7_mmu_cache_on:
#ifdef CONFIG_MMU
mrc p15, 0, r11, c0, c1, 4 @ read ID_MMFR0
tst r11, #0xf @ VMSA
+ movne r6, #CB_BITS | 0x02 @ !XN
blne __setup_mmu
mov r0, #0
mcr p15, 0, r0, c7, c10, 4 @ drain write buffer
@@ -648,16 +715,22 @@ __armv7_mmu_cache_on:
mcrne p15, 0, r0, c8, c7, 0 @ flush I,D TLBs
#endif
mrc p15, 0, r0, c1, c0, 0 @ read control reg
+ bic r0, r0, #1 << 28 @ clear SCTLR.TRE
orr r0, r0, #0x5000 @ I-cache enable, RR cache replacement
orr r0, r0, #0x003c @ write buffer
+ bic r0, r0, #2 @ A (no unaligned access fault)
+ orr r0, r0, #1 << 22 @ U (v6 unaligned access model)
+ @ (needed for ARM1176)
#ifdef CONFIG_MMU
-#ifdef CONFIG_CPU_ENDIAN_BE8
- orr r0, r0, #1 << 25 @ big-endian page tables
-#endif
+ ARM_BE8( orr r0, r0, #1 << 25 ) @ big-endian page tables
+ mrcne p15, 0, r6, c2, c0, 2 @ read ttb control reg
orrne r0, r0, #1 @ MMU enabled
- movne r1, #-1
+ movne r1, #0xfffffffd @ domain 0 = client
+ bic r6, r6, #1 << 31 @ 32-bit translation system
+ bic r6, r6, #3 << 0 @ use only ttbr0
mcrne p15, 0, r3, c2, c0, 0 @ load page table pointer
mcrne p15, 0, r1, c3, c0, 0 @ load domain access control
+ mcrne p15, 0, r6, c2, c0, 2 @ load ttb control
#endif
mcr p15, 0, r0, c7, c5, 4 @ ISB
mcr p15, 0, r0, c1, c0, 0 @ load control register
@@ -668,6 +741,7 @@ __armv7_mmu_cache_on:
__fa526_cache_on:
mov r12, lr
+ mov r6, #CB_BITS | 0x12 @ U
bl __setup_mmu
mov r0, #0
mcr p15, 0, r0, c7, c7, 0 @ Invalidate whole cache
@@ -680,18 +754,6 @@ __fa526_cache_on:
mcr p15, 0, r0, c8, c7, 0 @ flush UTLB
mov pc, r12
-__arm6_mmu_cache_on:
- mov r12, lr
- bl __setup_mmu
- mov r0, #0
- mcr p15, 0, r0, c7, c0, 0 @ invalidate whole cache v3
- mcr p15, 0, r0, c5, c0, 0 @ invalidate whole TLB v3
- mov r0, #0x30
- bl __common_mmu_cache_on
- mov r0, #0
- mcr p15, 0, r0, c5, c0, 0 @ invalidate whole TLB v3
- mov pc, r12
-
__common_mmu_cache_on:
#ifndef CONFIG_THUMB2_KERNEL
#ifndef DEBUG
@@ -756,18 +818,8 @@ call_cache_fn: adr r12, proc_types
.align 2
.type proc_types,#object
proc_types:
- .word 0x41560600 @ ARM6/610
- .word 0xffffffe0
- W(b) __arm6_mmu_cache_off @ works, but slow
- W(b) __arm6_mmu_cache_off
- mov pc, lr
- THUMB( nop )
-@ b __arm6_mmu_cache_on @ untested
-@ b __arm6_mmu_cache_off
-@ b __armv3_mmu_cache_flush
-
- .word 0x00000000 @ old ARM ID
- .word 0x0000f000
+ .word 0x41000000 @ old ARM ID
+ .word 0xff00f000
mov pc, lr
THUMB( nop )
mov pc, lr
@@ -777,8 +829,10 @@ proc_types:
.word 0x41007000 @ ARM7/710
.word 0xfff8fe00
- W(b) __arm7_mmu_cache_off
- W(b) __arm7_mmu_cache_off
+ mov pc, lr
+ THUMB( nop )
+ mov pc, lr
+ THUMB( nop )
mov pc, lr
THUMB( nop )
@@ -885,7 +939,7 @@ proc_types:
.word 0x0007b000 @ ARMv6
.word 0x000ff000
- W(b) __armv4_mmu_cache_on
+ W(b) __armv6_mmu_cache_on
W(b) __armv4_mmu_cache_off
W(b) __armv6_mmu_cache_flush
@@ -977,21 +1031,6 @@ __armv7_mmu_cache_off:
mcr p15, 0, r0, c7, c5, 4 @ ISB
mov pc, r12
-__arm6_mmu_cache_off:
- mov r0, #0x00000030 @ ARM6 control reg.
- b __armv3_mmu_cache_off
-
-__arm7_mmu_cache_off:
- mov r0, #0x00000070 @ ARM7 control reg.
- b __armv3_mmu_cache_off
-
-__armv3_mmu_cache_off:
- mcr p15, 0, r0, c1, c0, 0 @ turn MMU and cache off
- mov r0, #0
- mcr p15, 0, r0, c7, c0, 0 @ invalidate whole cache v3
- mcr p15, 0, r0, c5, c0, 0 @ invalidate whole TLB v3
- mov pc, lr
-
/*
* Clean and flush the cache to maintain consistency.
*
@@ -1220,6 +1259,25 @@ memdump: mov r12, r0
#endif
.ltorg
+
+#ifdef CONFIG_ARM_VIRT_EXT
+.align 5
+__hyp_reentry_vectors:
+ W(b) . @ reset
+ W(b) . @ undef
+ W(b) . @ svc
+ W(b) . @ pabort
+ W(b) . @ dabort
+ W(b) __enter_kernel @ hyp
+ W(b) . @ irq
+ W(b) . @ fiq
+#endif /* CONFIG_ARM_VIRT_EXT */
+
+__enter_kernel:
+ mov r0, #0 @ must be 0
+ ARM( mov pc, r4 ) @ call kernel
+ THUMB( bx r4 ) @ entry point is always ARM
+
reloc_code_end:
.align
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-09 13:59:32 +0000