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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/arm/kernel/head.S
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+/*
+ * linux/arch/arm/kernel/head.S
+ *
+ * Copyright (C) 1994-2002 Russell King
+ * Copyright (c) 2003 ARM Limited
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Kernel startup code for all 32-bit CPUs
+ */
+#include <linux/linkage.h>
+#include <linux/init.h>
+
+#include <asm/assembler.h>
+#include <asm/cp15.h>
+#include <asm/domain.h>
+#include <asm/ptrace.h>
+#include <asm/asm-offsets.h>
+#include <asm/memory.h>
+#include <asm/thread_info.h>
+#include <asm/pgtable.h>
+
+#if defined(CONFIG_DEBUG_LL) && !defined(CONFIG_DEBUG_SEMIHOSTING)
+#include CONFIG_DEBUG_LL_INCLUDE
+#endif
+
+/*
+ * swapper_pg_dir is the virtual address of the initial page table.
+ * We place the page tables 16K below KERNEL_RAM_VADDR. Therefore, we must
+ * make sure that KERNEL_RAM_VADDR is correctly set. Currently, we expect
+ * the least significant 16 bits to be 0x8000, but we could probably
+ * relax this restriction to KERNEL_RAM_VADDR >= PAGE_OFFSET + 0x4000.
+ */
+#define KERNEL_RAM_VADDR (PAGE_OFFSET + TEXT_OFFSET)
+#if (KERNEL_RAM_VADDR & 0xffff) != 0x8000
+#error KERNEL_RAM_VADDR must start at 0xXXXX8000
+#endif
+
+#ifdef CONFIG_ARM_LPAE
+ /* LPAE requires an additional page for the PGD */
+#define PG_DIR_SIZE 0x5000
+#define PMD_ORDER 3
+#else
+#define PG_DIR_SIZE 0x4000
+#define PMD_ORDER 2
+#endif
+
+ .globl swapper_pg_dir
+ .equ swapper_pg_dir, KERNEL_RAM_VADDR - PG_DIR_SIZE
+
+ .macro pgtbl, rd, phys
+ add \rd, \phys, #TEXT_OFFSET
+ sub \rd, \rd, #PG_DIR_SIZE
+ .endm
+
+/*
+ * Kernel startup entry point.
+ * ---------------------------
+ *
+ * This is normally called from the decompressor code. The requirements
+ * are: MMU = off, D-cache = off, I-cache = dont care, r0 = 0,
+ * r1 = machine nr, r2 = atags or dtb pointer.
+ *
+ * This code is mostly position independent, so if you link the kernel at
+ * 0xc0008000, you call this at __pa(0xc0008000).
+ *
+ * See linux/arch/arm/tools/mach-types for the complete list of machine
+ * numbers for r1.
+ *
+ * We're trying to keep crap to a minimum; DO NOT add any machine specific
+ * crap here - that's what the boot loader (or in extreme, well justified
+ * circumstances, zImage) is for.
+ */
+ .arm
+
+ __HEAD
+ENTRY(stext)
+ ARM_BE8(setend be ) @ ensure we are in BE8 mode
+
+ THUMB( adr r9, BSYM(1f) ) @ Kernel is always entered in ARM.
+ THUMB( bx r9 ) @ If this is a Thumb-2 kernel,
+ THUMB( .thumb ) @ switch to Thumb now.
+ THUMB(1: )
+
+#ifdef CONFIG_ARM_VIRT_EXT
+ bl __hyp_stub_install
+#endif
+ @ ensure svc mode and all interrupts masked
+ safe_svcmode_maskall r9
+
+ mrc p15, 0, r9, c0, c0 @ get processor id
+ bl __lookup_processor_type @ r5=procinfo r9=cpuid
+ movs r10, r5 @ invalid processor (r5=0)?
+ THUMB( it eq ) @ force fixup-able long branch encoding
+ beq __error_p @ yes, error 'p'
+
+#ifdef CONFIG_ARM_LPAE
+ mrc p15, 0, r3, c0, c1, 4 @ read ID_MMFR0
+ and r3, r3, #0xf @ extract VMSA support
+ cmp r3, #5 @ long-descriptor translation table format?
+ THUMB( it lo ) @ force fixup-able long branch encoding
+ blo __error_lpae @ only classic page table format
+#endif
+
+#ifndef CONFIG_XIP_KERNEL
+ adr r3, 2f
+ ldmia r3, {r4, r8}
+ sub r4, r3, r4 @ (PHYS_OFFSET - PAGE_OFFSET)
+ add r8, r8, r4 @ PHYS_OFFSET
+#else
+ ldr r8, =PLAT_PHYS_OFFSET @ always constant in this case
+#endif
+
+ /*
+ * r1 = machine no, r2 = atags or dtb,
+ * r8 = phys_offset, r9 = cpuid, r10 = procinfo
+ */
+ bl __vet_atags
+#ifdef CONFIG_SMP_ON_UP
+ bl __fixup_smp
+#endif
+#ifdef CONFIG_ARM_PATCH_PHYS_VIRT
+ bl __fixup_pv_table
+#endif
+ bl __create_page_tables
+
+ /*
+ * The following calls CPU specific code in a position independent
+ * manner. See arch/arm/mm/proc-*.S for details. r10 = base of
+ * xxx_proc_info structure selected by __lookup_processor_type
+ * above. On return, the CPU will be ready for the MMU to be
+ * turned on, and r0 will hold the CPU control register value.
+ */
+ ldr r13, =__mmap_switched @ address to jump to after
+ @ mmu has been enabled
+ adr lr, BSYM(1f) @ return (PIC) address
+ mov r8, r4 @ set TTBR1 to swapper_pg_dir
+ ldr r12, [r10, #PROCINFO_INITFUNC]
+ add r12, r12, r10
+ ret r12
+1: b __enable_mmu
+ENDPROC(stext)
+ .ltorg
+#ifndef CONFIG_XIP_KERNEL
+2: .long .
+ .long PAGE_OFFSET
+#endif
+
+/*
+ * Setup the initial page tables. We only setup the barest
+ * amount which are required to get the kernel running, which
+ * generally means mapping in the kernel code.
+ *
+ * r8 = phys_offset, r9 = cpuid, r10 = procinfo
+ *
+ * Returns:
+ * r0, r3, r5-r7 corrupted
+ * r4 = page table (see ARCH_PGD_SHIFT in asm/memory.h)
+ */
+__create_page_tables:
+ pgtbl r4, r8 @ page table address
+
+ /*
+ * Clear the swapper page table
+ */
+ mov r0, r4
+ mov r3, #0
+ add r6, r0, #PG_DIR_SIZE
+1: str r3, [r0], #4
+ str r3, [r0], #4
+ str r3, [r0], #4
+ str r3, [r0], #4
+ teq r0, r6
+ bne 1b
+
+#ifdef CONFIG_ARM_LPAE
+ /*
+ * Build the PGD table (first level) to point to the PMD table. A PGD
+ * entry is 64-bit wide.
+ */
+ mov r0, r4
+ add r3, r4, #0x1000 @ first PMD table address
+ orr r3, r3, #3 @ PGD block type
+ mov r6, #4 @ PTRS_PER_PGD
+ mov r7, #1 << (55 - 32) @ L_PGD_SWAPPER
+1:
+#ifdef CONFIG_CPU_ENDIAN_BE8
+ str r7, [r0], #4 @ set top PGD entry bits
+ str r3, [r0], #4 @ set bottom PGD entry bits
+#else
+ str r3, [r0], #4 @ set bottom PGD entry bits
+ str r7, [r0], #4 @ set top PGD entry bits
+#endif
+ add r3, r3, #0x1000 @ next PMD table
+ subs r6, r6, #1
+ bne 1b
+
+ add r4, r4, #0x1000 @ point to the PMD tables
+#ifdef CONFIG_CPU_ENDIAN_BE8
+ add r4, r4, #4 @ we only write the bottom word
+#endif
+#endif
+
+ ldr r7, [r10, #PROCINFO_MM_MMUFLAGS] @ mm_mmuflags
+
+ /*
+ * Create identity mapping to cater for __enable_mmu.
+ * This identity mapping will be removed by paging_init().
+ */
+ adr r0, __turn_mmu_on_loc
+ ldmia r0, {r3, r5, r6}
+ sub r0, r0, r3 @ virt->phys offset
+ add r5, r5, r0 @ phys __turn_mmu_on
+ add r6, r6, r0 @ phys __turn_mmu_on_end
+ mov r5, r5, lsr #SECTION_SHIFT
+ mov r6, r6, lsr #SECTION_SHIFT
+
+1: orr r3, r7, r5, lsl #SECTION_SHIFT @ flags + kernel base
+ str r3, [r4, r5, lsl #PMD_ORDER] @ identity mapping
+ cmp r5, r6
+ addlo r5, r5, #1 @ next section
+ blo 1b
+
+ /*
+ * Map our RAM from the start to the end of the kernel .bss section.
+ */
+ add r0, r4, #PAGE_OFFSET >> (SECTION_SHIFT - PMD_ORDER)
+ ldr r6, =(_end - 1)
+ orr r3, r8, r7
+ add r6, r4, r6, lsr #(SECTION_SHIFT - PMD_ORDER)
+1: str r3, [r0], #1 << PMD_ORDER
+ add r3, r3, #1 << SECTION_SHIFT
+ cmp r0, r6
+ bls 1b
+
+#ifdef CONFIG_XIP_KERNEL
+ /*
+ * Map the kernel image separately as it is not located in RAM.
+ */
+#define XIP_START XIP_VIRT_ADDR(CONFIG_XIP_PHYS_ADDR)
+ mov r3, pc
+ mov r3, r3, lsr #SECTION_SHIFT
+ orr r3, r7, r3, lsl #SECTION_SHIFT
+ add r0, r4, #(XIP_START & 0xff000000) >> (SECTION_SHIFT - PMD_ORDER)
+ str r3, [r0, #((XIP_START & 0x00f00000) >> SECTION_SHIFT) << PMD_ORDER]!
+ ldr r6, =(_edata_loc - 1)
+ add r0, r0, #1 << PMD_ORDER
+ add r6, r4, r6, lsr #(SECTION_SHIFT - PMD_ORDER)
+1: cmp r0, r6
+ add r3, r3, #1 << SECTION_SHIFT
+ strls r3, [r0], #1 << PMD_ORDER
+ bls 1b
+#endif
+
+ /*
+ * Then map boot params address in r2 if specified.
+ * We map 2 sections in case the ATAGs/DTB crosses a section boundary.
+ */
+ mov r0, r2, lsr #SECTION_SHIFT
+ movs r0, r0, lsl #SECTION_SHIFT
+ subne r3, r0, r8
+ addne r3, r3, #PAGE_OFFSET
+ addne r3, r4, r3, lsr #(SECTION_SHIFT - PMD_ORDER)
+ orrne r6, r7, r0
+ strne r6, [r3], #1 << PMD_ORDER
+ addne r6, r6, #1 << SECTION_SHIFT
+ strne r6, [r3]
+
+#if defined(CONFIG_ARM_LPAE) && defined(CONFIG_CPU_ENDIAN_BE8)
+ sub r4, r4, #4 @ Fixup page table pointer
+ @ for 64-bit descriptors
+#endif
+
+#ifdef CONFIG_DEBUG_LL
+#if !defined(CONFIG_DEBUG_ICEDCC) && !defined(CONFIG_DEBUG_SEMIHOSTING)
+ /*
+ * Map in IO space for serial debugging.
+ * This allows debug messages to be output
+ * via a serial console before paging_init.
+ */
+ addruart r7, r3, r0
+
+ mov r3, r3, lsr #SECTION_SHIFT
+ mov r3, r3, lsl #PMD_ORDER
+
+ add r0, r4, r3
+ mov r3, r7, lsr #SECTION_SHIFT
+ ldr r7, [r10, #PROCINFO_IO_MMUFLAGS] @ io_mmuflags
+ orr r3, r7, r3, lsl #SECTION_SHIFT
+#ifdef CONFIG_ARM_LPAE
+ mov r7, #1 << (54 - 32) @ XN
+#ifdef CONFIG_CPU_ENDIAN_BE8
+ str r7, [r0], #4
+ str r3, [r0], #4
+#else
+ str r3, [r0], #4
+ str r7, [r0], #4
+#endif
+#else
+ orr r3, r3, #PMD_SECT_XN
+ str r3, [r0], #4
+#endif
+
+#else /* CONFIG_DEBUG_ICEDCC || CONFIG_DEBUG_SEMIHOSTING */
+ /* we don't need any serial debugging mappings */
+ ldr r7, [r10, #PROCINFO_IO_MMUFLAGS] @ io_mmuflags
+#endif
+
+#if defined(CONFIG_ARCH_NETWINDER) || defined(CONFIG_ARCH_CATS)
+ /*
+ * If we're using the NetWinder or CATS, we also need to map
+ * in the 16550-type serial port for the debug messages
+ */
+ add r0, r4, #0xff000000 >> (SECTION_SHIFT - PMD_ORDER)
+ orr r3, r7, #0x7c000000
+ str r3, [r0]
+#endif
+#ifdef CONFIG_ARCH_RPC
+ /*
+ * Map in screen at 0x02000000 & SCREEN2_BASE
+ * Similar reasons here - for debug. This is
+ * only for Acorn RiscPC architectures.
+ */
+ add r0, r4, #0x02000000 >> (SECTION_SHIFT - PMD_ORDER)
+ orr r3, r7, #0x02000000
+ str r3, [r0]
+ add r0, r4, #0xd8000000 >> (SECTION_SHIFT - PMD_ORDER)
+ str r3, [r0]
+#endif
+#endif
+#ifdef CONFIG_ARM_LPAE
+ sub r4, r4, #0x1000 @ point to the PGD table
+ mov r4, r4, lsr #ARCH_PGD_SHIFT
+#endif
+ ret lr
+ENDPROC(__create_page_tables)
+ .ltorg
+ .align
+__turn_mmu_on_loc:
+ .long .
+ .long __turn_mmu_on
+ .long __turn_mmu_on_end
+
+#if defined(CONFIG_SMP)
+ .text
+ENTRY(secondary_startup_arm)
+ .arm
+ THUMB( adr r9, BSYM(1f) ) @ Kernel is entered in ARM.
+ THUMB( bx r9 ) @ If this is a Thumb-2 kernel,
+ THUMB( .thumb ) @ switch to Thumb now.
+ THUMB(1: )
+ENTRY(secondary_startup)
+ /*
+ * Common entry point for secondary CPUs.
+ *
+ * Ensure that we're in SVC mode, and IRQs are disabled. Lookup
+ * the processor type - there is no need to check the machine type
+ * as it has already been validated by the primary processor.
+ */
+
+ ARM_BE8(setend be) @ ensure we are in BE8 mode
+
+#ifdef CONFIG_ARM_VIRT_EXT
+ bl __hyp_stub_install_secondary
+#endif
+ safe_svcmode_maskall r9
+
+ mrc p15, 0, r9, c0, c0 @ get processor id
+ bl __lookup_processor_type
+ movs r10, r5 @ invalid processor?
+ moveq r0, #'p' @ yes, error 'p'
+ THUMB( it eq ) @ force fixup-able long branch encoding
+ beq __error_p
+
+ /*
+ * Use the page tables supplied from __cpu_up.
+ */
+ adr r4, __secondary_data
+ ldmia r4, {r5, r7, r12} @ address to jump to after
+ sub lr, r4, r5 @ mmu has been enabled
+ ldr r4, [r7, lr] @ get secondary_data.pgdir
+ add r7, r7, #4
+ ldr r8, [r7, lr] @ get secondary_data.swapper_pg_dir
+ adr lr, BSYM(__enable_mmu) @ return address
+ mov r13, r12 @ __secondary_switched address
+ ldr r12, [r10, #PROCINFO_INITFUNC]
+ add r12, r12, r10 @ initialise processor
+ @ (return control reg)
+ ret r12
+ENDPROC(secondary_startup)
+ENDPROC(secondary_startup_arm)
+
+ /*
+ * r6 = &secondary_data
+ */
+ENTRY(__secondary_switched)
+ ldr sp, [r7, #4] @ get secondary_data.stack
+ mov fp, #0
+ b secondary_start_kernel
+ENDPROC(__secondary_switched)
+
+ .align
+
+ .type __secondary_data, %object
+__secondary_data:
+ .long .
+ .long secondary_data
+ .long __secondary_switched
+#endif /* defined(CONFIG_SMP) */
+
+
+
+/*
+ * Setup common bits before finally enabling the MMU. Essentially
+ * this is just loading the page table pointer and domain access
+ * registers.
+ *
+ * r0 = cp#15 control register
+ * r1 = machine ID
+ * r2 = atags or dtb pointer
+ * r4 = page table (see ARCH_PGD_SHIFT in asm/memory.h)
+ * r9 = processor ID
+ * r13 = *virtual* address to jump to upon completion
+ */
+__enable_mmu:
+#if defined(CONFIG_ALIGNMENT_TRAP) && __LINUX_ARM_ARCH__ < 6
+ orr r0, r0, #CR_A
+#else
+ bic r0, r0, #CR_A
+#endif
+#ifdef CONFIG_CPU_DCACHE_DISABLE
+ bic r0, r0, #CR_C
+#endif
+#ifdef CONFIG_CPU_BPREDICT_DISABLE
+ bic r0, r0, #CR_Z
+#endif
+#ifdef CONFIG_CPU_ICACHE_DISABLE
+ bic r0, r0, #CR_I
+#endif
+#ifndef CONFIG_ARM_LPAE
+ mov r5, #(domain_val(DOMAIN_USER, DOMAIN_MANAGER) | \
+ domain_val(DOMAIN_KERNEL, DOMAIN_MANAGER) | \
+ domain_val(DOMAIN_TABLE, DOMAIN_MANAGER) | \
+ domain_val(DOMAIN_IO, DOMAIN_CLIENT))
+ mcr p15, 0, r5, c3, c0, 0 @ load domain access register
+ mcr p15, 0, r4, c2, c0, 0 @ load page table pointer
+#endif
+ b __turn_mmu_on
+ENDPROC(__enable_mmu)
+
+/*
+ * Enable the MMU. This completely changes the structure of the visible
+ * memory space. You will not be able to trace execution through this.
+ * If you have an enquiry about this, *please* check the linux-arm-kernel
+ * mailing list archives BEFORE sending another post to the list.
+ *
+ * r0 = cp#15 control register
+ * r1 = machine ID
+ * r2 = atags or dtb pointer
+ * r9 = processor ID
+ * r13 = *virtual* address to jump to upon completion
+ *
+ * other registers depend on the function called upon completion
+ */
+ .align 5
+ .pushsection .idmap.text, "ax"
+ENTRY(__turn_mmu_on)
+ mov r0, r0
+ instr_sync
+ mcr p15, 0, r0, c1, c0, 0 @ write control reg
+ mrc p15, 0, r3, c0, c0, 0 @ read id reg
+ instr_sync
+ mov r3, r3
+ mov r3, r13
+ ret r3
+__turn_mmu_on_end:
+ENDPROC(__turn_mmu_on)
+ .popsection
+
+
+#ifdef CONFIG_SMP_ON_UP
+ __HEAD
+__fixup_smp:
+ and r3, r9, #0x000f0000 @ architecture version
+ teq r3, #0x000f0000 @ CPU ID supported?
+ bne __fixup_smp_on_up @ no, assume UP
+
+ bic r3, r9, #0x00ff0000
+ bic r3, r3, #0x0000000f @ mask 0xff00fff0
+ mov r4, #0x41000000
+ orr r4, r4, #0x0000b000
+ orr r4, r4, #0x00000020 @ val 0x4100b020
+ teq r3, r4 @ ARM 11MPCore?
+ reteq lr @ yes, assume SMP
+
+ mrc p15, 0, r0, c0, c0, 5 @ read MPIDR
+ and r0, r0, #0xc0000000 @ multiprocessing extensions and
+ teq r0, #0x80000000 @ not part of a uniprocessor system?
+ bne __fixup_smp_on_up @ no, assume UP
+
+ @ Core indicates it is SMP. Check for Aegis SOC where a single
+ @ Cortex-A9 CPU is present but SMP operations fault.
+ mov r4, #0x41000000
+ orr r4, r4, #0x0000c000
+ orr r4, r4, #0x00000090
+ teq r3, r4 @ Check for ARM Cortex-A9
+ retne lr @ Not ARM Cortex-A9,
+
+ @ If a future SoC *does* use 0x0 as the PERIPH_BASE, then the
+ @ below address check will need to be #ifdef'd or equivalent
+ @ for the Aegis platform.
+ mrc p15, 4, r0, c15, c0 @ get SCU base address
+ teq r0, #0x0 @ '0' on actual UP A9 hardware
+ beq __fixup_smp_on_up @ So its an A9 UP
+ ldr r0, [r0, #4] @ read SCU Config
+ARM_BE8(rev r0, r0) @ byteswap if big endian
+ and r0, r0, #0x3 @ number of CPUs
+ teq r0, #0x0 @ is 1?
+ retne lr
+
+__fixup_smp_on_up:
+ adr r0, 1f
+ ldmia r0, {r3 - r5}
+ sub r3, r0, r3
+ add r4, r4, r3
+ add r5, r5, r3
+ b __do_fixup_smp_on_up
+ENDPROC(__fixup_smp)
+
+ .align
+1: .word .
+ .word __smpalt_begin
+ .word __smpalt_end
+
+ .pushsection .data
+ .globl smp_on_up
+smp_on_up:
+ ALT_SMP(.long 1)
+ ALT_UP(.long 0)
+ .popsection
+#endif
+
+ .text
+__do_fixup_smp_on_up:
+ cmp r4, r5
+ reths lr
+ ldmia r4!, {r0, r6}
+ ARM( str r6, [r0, r3] )
+ THUMB( add r0, r0, r3 )
+#ifdef __ARMEB__
+ THUMB( mov r6, r6, ror #16 ) @ Convert word order for big-endian.
+#endif
+ THUMB( strh r6, [r0], #2 ) @ For Thumb-2, store as two halfwords
+ THUMB( mov r6, r6, lsr #16 ) @ to be robust against misaligned r3.
+ THUMB( strh r6, [r0] )
+ b __do_fixup_smp_on_up
+ENDPROC(__do_fixup_smp_on_up)
+
+ENTRY(fixup_smp)
+ stmfd sp!, {r4 - r6, lr}
+ mov r4, r0
+ add r5, r0, r1
+ mov r3, #0
+ bl __do_fixup_smp_on_up
+ ldmfd sp!, {r4 - r6, pc}
+ENDPROC(fixup_smp)
+
+#ifdef __ARMEB__
+#define LOW_OFFSET 0x4
+#define HIGH_OFFSET 0x0
+#else
+#define LOW_OFFSET 0x0
+#define HIGH_OFFSET 0x4
+#endif
+
+#ifdef CONFIG_ARM_PATCH_PHYS_VIRT
+
+/* __fixup_pv_table - patch the stub instructions with the delta between
+ * PHYS_OFFSET and PAGE_OFFSET, which is assumed to be 16MiB aligned and
+ * can be expressed by an immediate shifter operand. The stub instruction
+ * has a form of '(add|sub) rd, rn, #imm'.
+ */
+ __HEAD
+__fixup_pv_table:
+ adr r0, 1f
+ ldmia r0, {r3-r7}
+ mvn ip, #0
+ subs r3, r0, r3 @ PHYS_OFFSET - PAGE_OFFSET
+ add r4, r4, r3 @ adjust table start address
+ add r5, r5, r3 @ adjust table end address
+ add r6, r6, r3 @ adjust __pv_phys_pfn_offset address
+ add r7, r7, r3 @ adjust __pv_offset address
+ mov r0, r8, lsr #PAGE_SHIFT @ convert to PFN
+ str r0, [r6] @ save computed PHYS_OFFSET to __pv_phys_pfn_offset
+ strcc ip, [r7, #HIGH_OFFSET] @ save to __pv_offset high bits
+ mov r6, r3, lsr #24 @ constant for add/sub instructions
+ teq r3, r6, lsl #24 @ must be 16MiB aligned
+THUMB( it ne @ cross section branch )
+ bne __error
+ str r3, [r7, #LOW_OFFSET] @ save to __pv_offset low bits
+ b __fixup_a_pv_table
+ENDPROC(__fixup_pv_table)
+
+ .align
+1: .long .
+ .long __pv_table_begin
+ .long __pv_table_end
+2: .long __pv_phys_pfn_offset
+ .long __pv_offset
+
+ .text
+__fixup_a_pv_table:
+ adr r0, 3f
+ ldr r6, [r0]
+ add r6, r6, r3
+ ldr r0, [r6, #HIGH_OFFSET] @ pv_offset high word
+ ldr r6, [r6, #LOW_OFFSET] @ pv_offset low word
+ mov r6, r6, lsr #24
+ cmn r0, #1
+#ifdef CONFIG_THUMB2_KERNEL
+ moveq r0, #0x200000 @ set bit 21, mov to mvn instruction
+ lsls r6, #24
+ beq 2f
+ clz r7, r6
+ lsr r6, #24
+ lsl r6, r7
+ bic r6, #0x0080
+ lsrs r7, #1
+ orrcs r6, #0x0080
+ orr r6, r6, r7, lsl #12
+ orr r6, #0x4000
+ b 2f
+1: add r7, r3
+ ldrh ip, [r7, #2]
+ARM_BE8(rev16 ip, ip)
+ tst ip, #0x4000
+ and ip, #0x8f00
+ orrne ip, r6 @ mask in offset bits 31-24
+ orreq ip, r0 @ mask in offset bits 7-0
+ARM_BE8(rev16 ip, ip)
+ strh ip, [r7, #2]
+ bne 2f
+ ldrh ip, [r7]
+ARM_BE8(rev16 ip, ip)
+ bic ip, #0x20
+ orr ip, ip, r0, lsr #16
+ARM_BE8(rev16 ip, ip)
+ strh ip, [r7]
+2: cmp r4, r5
+ ldrcc r7, [r4], #4 @ use branch for delay slot
+ bcc 1b
+ bx lr
+#else
+#ifdef CONFIG_CPU_ENDIAN_BE8
+ moveq r0, #0x00004000 @ set bit 22, mov to mvn instruction
+#else
+ moveq r0, #0x400000 @ set bit 22, mov to mvn instruction
+#endif
+ b 2f
+1: ldr ip, [r7, r3]
+#ifdef CONFIG_CPU_ENDIAN_BE8
+ @ in BE8, we load data in BE, but instructions still in LE
+ bic ip, ip, #0xff000000
+ tst ip, #0x000f0000 @ check the rotation field
+ orrne ip, ip, r6, lsl #24 @ mask in offset bits 31-24
+ biceq ip, ip, #0x00004000 @ clear bit 22
+ orreq ip, ip, r0 @ mask in offset bits 7-0
+#else
+ bic ip, ip, #0x000000ff
+ tst ip, #0xf00 @ check the rotation field
+ orrne ip, ip, r6 @ mask in offset bits 31-24
+ biceq ip, ip, #0x400000 @ clear bit 22
+ orreq ip, ip, r0 @ mask in offset bits 7-0
+#endif
+ str ip, [r7, r3]
+2: cmp r4, r5
+ ldrcc r7, [r4], #4 @ use branch for delay slot
+ bcc 1b
+ ret lr
+#endif
+ENDPROC(__fixup_a_pv_table)
+
+ .align
+3: .long __pv_offset
+
+ENTRY(fixup_pv_table)
+ stmfd sp!, {r4 - r7, lr}
+ mov r3, #0 @ no offset
+ mov r4, r0 @ r0 = table start
+ add r5, r0, r1 @ r1 = table size
+ bl __fixup_a_pv_table
+ ldmfd sp!, {r4 - r7, pc}
+ENDPROC(fixup_pv_table)
+
+ .data
+ .globl __pv_phys_pfn_offset
+ .type __pv_phys_pfn_offset, %object
+__pv_phys_pfn_offset:
+ .word 0
+ .size __pv_phys_pfn_offset, . -__pv_phys_pfn_offset
+
+ .globl __pv_offset
+ .type __pv_offset, %object
+__pv_offset:
+ .quad 0
+ .size __pv_offset, . -__pv_offset
+#endif
+
+#include "head-common.S"