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diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h
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+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Based on arch/arm/include/asm/assembler.h, arch/arm/mm/proc-macros.S
+ *
+ * Copyright (C) 1996-2000 Russell King
+ * Copyright (C) 2012 ARM Ltd.
+ */
+#ifndef __ASSEMBLY__
+#error "Only include this from assembly code"
+#endif
+
+#ifndef __ASM_ASSEMBLER_H
+#define __ASM_ASSEMBLER_H
+
+#include <asm-generic/export.h>
+
+#include <asm/asm-offsets.h>
+#include <asm/cpufeature.h>
+#include <asm/cputype.h>
+#include <asm/debug-monitors.h>
+#include <asm/page.h>
+#include <asm/pgtable-hwdef.h>
+#include <asm/ptrace.h>
+#include <asm/thread_info.h>
+
+ .macro save_and_disable_daif, flags
+ mrs \flags, daif
+ msr daifset, #0xf
+ .endm
+
+ .macro disable_daif
+ msr daifset, #0xf
+ .endm
+
+ .macro enable_daif
+ msr daifclr, #0xf
+ .endm
+
+ .macro restore_daif, flags:req
+ msr daif, \flags
+ .endm
+
+ /* IRQ is the lowest priority flag, unconditionally unmask the rest. */
+ .macro enable_da_f
+ msr daifclr, #(8 | 4 | 1)
+ .endm
+
+/*
+ * Save/restore interrupts.
+ */
+ .macro save_and_disable_irq, flags
+ mrs \flags, daif
+ msr daifset, #2
+ .endm
+
+ .macro restore_irq, flags
+ msr daif, \flags
+ .endm
+
+ .macro enable_dbg
+ msr daifclr, #8
+ .endm
+
+ .macro disable_step_tsk, flgs, tmp
+ tbz \flgs, #TIF_SINGLESTEP, 9990f
+ mrs \tmp, mdscr_el1
+ bic \tmp, \tmp, #DBG_MDSCR_SS
+ msr mdscr_el1, \tmp
+ isb // Synchronise with enable_dbg
+9990:
+ .endm
+
+ /* call with daif masked */
+ .macro enable_step_tsk, flgs, tmp
+ tbz \flgs, #TIF_SINGLESTEP, 9990f
+ mrs \tmp, mdscr_el1
+ orr \tmp, \tmp, #DBG_MDSCR_SS
+ msr mdscr_el1, \tmp
+9990:
+ .endm
+
+/*
+ * RAS Error Synchronization barrier
+ */
+ .macro esb
+#ifdef CONFIG_ARM64_RAS_EXTN
+ hint #16
+#else
+ nop
+#endif
+ .endm
+
+/*
+ * Value prediction barrier
+ */
+ .macro csdb
+ hint #20
+ .endm
+
+/*
+ * Clear Branch History instruction
+ */
+ .macro clearbhb
+ hint #22
+ .endm
+
+/*
+ * Speculation barrier
+ */
+ .macro sb
+alternative_if_not ARM64_HAS_SB
+ dsb nsh
+ isb
+alternative_else
+ SB_BARRIER_INSN
+ nop
+alternative_endif
+ .endm
+
+/*
+ * NOP sequence
+ */
+ .macro nops, num
+ .rept \num
+ nop
+ .endr
+ .endm
+
+/*
+ * Emit an entry into the exception table
+ */
+ .macro _asm_extable, from, to
+ .pushsection __ex_table, "a"
+ .align 3
+ .long (\from - .), (\to - .)
+ .popsection
+ .endm
+
+#define USER(l, x...) \
+9999: x; \
+ _asm_extable 9999b, l
+
+/*
+ * Register aliases.
+ */
+lr .req x30 // link register
+
+/*
+ * Vector entry
+ */
+ .macro ventry label
+ .align 7
+ b \label
+ .endm
+
+/*
+ * Select code when configured for BE.
+ */
+#ifdef CONFIG_CPU_BIG_ENDIAN
+#define CPU_BE(code...) code
+#else
+#define CPU_BE(code...)
+#endif
+
+/*
+ * Select code when configured for LE.
+ */
+#ifdef CONFIG_CPU_BIG_ENDIAN
+#define CPU_LE(code...)
+#else
+#define CPU_LE(code...) code
+#endif
+
+/*
+ * Define a macro that constructs a 64-bit value by concatenating two
+ * 32-bit registers. Note that on big endian systems the order of the
+ * registers is swapped.
+ */
+#ifndef CONFIG_CPU_BIG_ENDIAN
+ .macro regs_to_64, rd, lbits, hbits
+#else
+ .macro regs_to_64, rd, hbits, lbits
+#endif
+ orr \rd, \lbits, \hbits, lsl #32
+ .endm
+
+/*
+ * Pseudo-ops for PC-relative adr/ldr/str <reg>, <symbol> where
+ * <symbol> is within the range +/- 4 GB of the PC.
+ */
+ /*
+ * @dst: destination register (64 bit wide)
+ * @sym: name of the symbol
+ */
+ .macro adr_l, dst, sym
+ adrp \dst, \sym
+ add \dst, \dst, :lo12:\sym
+ .endm
+
+ /*
+ * @dst: destination register (32 or 64 bit wide)
+ * @sym: name of the symbol
+ * @tmp: optional 64-bit scratch register to be used if <dst> is a
+ * 32-bit wide register, in which case it cannot be used to hold
+ * the address
+ */
+ .macro ldr_l, dst, sym, tmp=
+ .ifb \tmp
+ adrp \dst, \sym
+ ldr \dst, [\dst, :lo12:\sym]
+ .else
+ adrp \tmp, \sym
+ ldr \dst, [\tmp, :lo12:\sym]
+ .endif
+ .endm
+
+ /*
+ * @src: source register (32 or 64 bit wide)
+ * @sym: name of the symbol
+ * @tmp: mandatory 64-bit scratch register to calculate the address
+ * while <src> needs to be preserved.
+ */
+ .macro str_l, src, sym, tmp
+ adrp \tmp, \sym
+ str \src, [\tmp, :lo12:\sym]
+ .endm
+
+ /*
+ * @dst: destination register
+ */
+#if defined(__KVM_NVHE_HYPERVISOR__) || defined(__KVM_VHE_HYPERVISOR__)
+ .macro this_cpu_offset, dst
+ mrs \dst, tpidr_el2
+ .endm
+#else
+ .macro this_cpu_offset, dst
+alternative_if_not ARM64_HAS_VIRT_HOST_EXTN
+ mrs \dst, tpidr_el1
+alternative_else
+ mrs \dst, tpidr_el2
+alternative_endif
+ .endm
+#endif
+
+ /*
+ * @dst: Result of per_cpu(sym, smp_processor_id()) (can be SP)
+ * @sym: The name of the per-cpu variable
+ * @tmp: scratch register
+ */
+ .macro adr_this_cpu, dst, sym, tmp
+ adrp \tmp, \sym
+ add \dst, \tmp, #:lo12:\sym
+ this_cpu_offset \tmp
+ add \dst, \dst, \tmp
+ .endm
+
+ /*
+ * @dst: Result of READ_ONCE(per_cpu(sym, smp_processor_id()))
+ * @sym: The name of the per-cpu variable
+ * @tmp: scratch register
+ */
+ .macro ldr_this_cpu dst, sym, tmp
+ adr_l \dst, \sym
+ this_cpu_offset \tmp
+ ldr \dst, [\dst, \tmp]
+ .endm
+
+/*
+ * vma_vm_mm - get mm pointer from vma pointer (vma->vm_mm)
+ */
+ .macro vma_vm_mm, rd, rn
+ ldr \rd, [\rn, #VMA_VM_MM]
+ .endm
+
+/*
+ * read_ctr - read CTR_EL0. If the system has mismatched register fields,
+ * provide the system wide safe value from arm64_ftr_reg_ctrel0.sys_val
+ */
+ .macro read_ctr, reg
+alternative_if_not ARM64_MISMATCHED_CACHE_TYPE
+ mrs \reg, ctr_el0 // read CTR
+ nop
+alternative_else
+ ldr_l \reg, arm64_ftr_reg_ctrel0 + ARM64_FTR_SYSVAL
+alternative_endif
+ .endm
+
+
+/*
+ * raw_dcache_line_size - get the minimum D-cache line size on this CPU
+ * from the CTR register.
+ */
+ .macro raw_dcache_line_size, reg, tmp
+ mrs \tmp, ctr_el0 // read CTR
+ ubfm \tmp, \tmp, #16, #19 // cache line size encoding
+ mov \reg, #4 // bytes per word
+ lsl \reg, \reg, \tmp // actual cache line size
+ .endm
+
+/*
+ * dcache_line_size - get the safe D-cache line size across all CPUs
+ */
+ .macro dcache_line_size, reg, tmp
+ read_ctr \tmp
+ ubfm \tmp, \tmp, #16, #19 // cache line size encoding
+ mov \reg, #4 // bytes per word
+ lsl \reg, \reg, \tmp // actual cache line size
+ .endm
+
+/*
+ * raw_icache_line_size - get the minimum I-cache line size on this CPU
+ * from the CTR register.
+ */
+ .macro raw_icache_line_size, reg, tmp
+ mrs \tmp, ctr_el0 // read CTR
+ and \tmp, \tmp, #0xf // cache line size encoding
+ mov \reg, #4 // bytes per word
+ lsl \reg, \reg, \tmp // actual cache line size
+ .endm
+
+/*
+ * icache_line_size - get the safe I-cache line size across all CPUs
+ */
+ .macro icache_line_size, reg, tmp
+ read_ctr \tmp
+ and \tmp, \tmp, #0xf // cache line size encoding
+ mov \reg, #4 // bytes per word
+ lsl \reg, \reg, \tmp // actual cache line size
+ .endm
+
+/*
+ * tcr_set_t0sz - update TCR.T0SZ so that we can load the ID map
+ */
+ .macro tcr_set_t0sz, valreg, t0sz
+ bfi \valreg, \t0sz, #TCR_T0SZ_OFFSET, #TCR_TxSZ_WIDTH
+ .endm
+
+/*
+ * tcr_set_t1sz - update TCR.T1SZ
+ */
+ .macro tcr_set_t1sz, valreg, t1sz
+ bfi \valreg, \t1sz, #TCR_T1SZ_OFFSET, #TCR_TxSZ_WIDTH
+ .endm
+
+/*
+ * tcr_compute_pa_size - set TCR.(I)PS to the highest supported
+ * ID_AA64MMFR0_EL1.PARange value
+ *
+ * tcr: register with the TCR_ELx value to be updated
+ * pos: IPS or PS bitfield position
+ * tmp{0,1}: temporary registers
+ */
+ .macro tcr_compute_pa_size, tcr, pos, tmp0, tmp1
+ mrs \tmp0, ID_AA64MMFR0_EL1
+ // Narrow PARange to fit the PS field in TCR_ELx
+ ubfx \tmp0, \tmp0, #ID_AA64MMFR0_PARANGE_SHIFT, #3
+ mov \tmp1, #ID_AA64MMFR0_PARANGE_MAX
+ cmp \tmp0, \tmp1
+ csel \tmp0, \tmp1, \tmp0, hi
+ bfi \tcr, \tmp0, \pos, #3
+ .endm
+
+/*
+ * Macro to perform a data cache maintenance for the interval
+ * [kaddr, kaddr + size)
+ *
+ * op: operation passed to dc instruction
+ * domain: domain used in dsb instruciton
+ * kaddr: starting virtual address of the region
+ * size: size of the region
+ * Corrupts: kaddr, size, tmp1, tmp2
+ */
+ .macro __dcache_op_workaround_clean_cache, op, kaddr
+alternative_if_not ARM64_WORKAROUND_CLEAN_CACHE
+ dc \op, \kaddr
+alternative_else
+ dc civac, \kaddr
+alternative_endif
+ .endm
+
+ .macro dcache_by_line_op op, domain, kaddr, size, tmp1, tmp2
+ dcache_line_size \tmp1, \tmp2
+ add \size, \kaddr, \size
+ sub \tmp2, \tmp1, #1
+ bic \kaddr, \kaddr, \tmp2
+9998:
+ .ifc \op, cvau
+ __dcache_op_workaround_clean_cache \op, \kaddr
+ .else
+ .ifc \op, cvac
+ __dcache_op_workaround_clean_cache \op, \kaddr
+ .else
+ .ifc \op, cvap
+ sys 3, c7, c12, 1, \kaddr // dc cvap
+ .else
+ .ifc \op, cvadp
+ sys 3, c7, c13, 1, \kaddr // dc cvadp
+ .else
+ dc \op, \kaddr
+ .endif
+ .endif
+ .endif
+ .endif
+ add \kaddr, \kaddr, \tmp1
+ cmp \kaddr, \size
+ b.lo 9998b
+ dsb \domain
+ .endm
+
+/*
+ * Macro to perform an instruction cache maintenance for the interval
+ * [start, end)
+ *
+ * start, end: virtual addresses describing the region
+ * label: A label to branch to on user fault.
+ * Corrupts: tmp1, tmp2
+ */
+ .macro invalidate_icache_by_line start, end, tmp1, tmp2, label
+ icache_line_size \tmp1, \tmp2
+ sub \tmp2, \tmp1, #1
+ bic \tmp2, \start, \tmp2
+9997:
+USER(\label, ic ivau, \tmp2) // invalidate I line PoU
+ add \tmp2, \tmp2, \tmp1
+ cmp \tmp2, \end
+ b.lo 9997b
+ dsb ish
+ isb
+ .endm
+
+/*
+ * reset_pmuserenr_el0 - reset PMUSERENR_EL0 if PMUv3 present
+ */
+ .macro reset_pmuserenr_el0, tmpreg
+ mrs \tmpreg, id_aa64dfr0_el1
+ sbfx \tmpreg, \tmpreg, #ID_AA64DFR0_PMUVER_SHIFT, #4
+ cmp \tmpreg, #1 // Skip if no PMU present
+ b.lt 9000f
+ msr pmuserenr_el0, xzr // Disable PMU access from EL0
+9000:
+ .endm
+
+/*
+ * reset_amuserenr_el0 - reset AMUSERENR_EL0 if AMUv1 present
+ */
+ .macro reset_amuserenr_el0, tmpreg
+ mrs \tmpreg, id_aa64pfr0_el1 // Check ID_AA64PFR0_EL1
+ ubfx \tmpreg, \tmpreg, #ID_AA64PFR0_AMU_SHIFT, #4
+ cbz \tmpreg, .Lskip_\@ // Skip if no AMU present
+ msr_s SYS_AMUSERENR_EL0, xzr // Disable AMU access from EL0
+.Lskip_\@:
+ .endm
+/*
+ * copy_page - copy src to dest using temp registers t1-t8
+ */
+ .macro copy_page dest:req src:req t1:req t2:req t3:req t4:req t5:req t6:req t7:req t8:req
+9998: ldp \t1, \t2, [\src]
+ ldp \t3, \t4, [\src, #16]
+ ldp \t5, \t6, [\src, #32]
+ ldp \t7, \t8, [\src, #48]
+ add \src, \src, #64
+ stnp \t1, \t2, [\dest]
+ stnp \t3, \t4, [\dest, #16]
+ stnp \t5, \t6, [\dest, #32]
+ stnp \t7, \t8, [\dest, #48]
+ add \dest, \dest, #64
+ tst \src, #(PAGE_SIZE - 1)
+ b.ne 9998b
+ .endm
+
+/*
+ * Annotate a function as being unsuitable for kprobes.
+ */
+#ifdef CONFIG_KPROBES
+#define NOKPROBE(x) \
+ .pushsection "_kprobe_blacklist", "aw"; \
+ .quad x; \
+ .popsection;
+#else
+#define NOKPROBE(x)
+#endif
+
+#ifdef CONFIG_KASAN
+#define EXPORT_SYMBOL_NOKASAN(name)
+#else
+#define EXPORT_SYMBOL_NOKASAN(name) EXPORT_SYMBOL(name)
+#endif
+
+ /*
+ * Emit a 64-bit absolute little endian symbol reference in a way that
+ * ensures that it will be resolved at build time, even when building a
+ * PIE binary. This requires cooperation from the linker script, which
+ * must emit the lo32/hi32 halves individually.
+ */
+ .macro le64sym, sym
+ .long \sym\()_lo32
+ .long \sym\()_hi32
+ .endm
+
+ /*
+ * mov_q - move an immediate constant into a 64-bit register using
+ * between 2 and 4 movz/movk instructions (depending on the
+ * magnitude and sign of the operand)
+ */
+ .macro mov_q, reg, val
+ .if (((\val) >> 31) == 0 || ((\val) >> 31) == 0x1ffffffff)
+ movz \reg, :abs_g1_s:\val
+ .else
+ .if (((\val) >> 47) == 0 || ((\val) >> 47) == 0x1ffff)
+ movz \reg, :abs_g2_s:\val
+ .else
+ movz \reg, :abs_g3:\val
+ movk \reg, :abs_g2_nc:\val
+ .endif
+ movk \reg, :abs_g1_nc:\val
+ .endif
+ movk \reg, :abs_g0_nc:\val
+ .endm
+
+/*
+ * Return the current task_struct.
+ */
+ .macro get_current_task, rd
+ mrs \rd, sp_el0
+ .endm
+
+/*
+ * Offset ttbr1 to allow for 48-bit kernel VAs set with 52-bit PTRS_PER_PGD.
+ * orr is used as it can cover the immediate value (and is idempotent).
+ * In future this may be nop'ed out when dealing with 52-bit kernel VAs.
+ * ttbr: Value of ttbr to set, modified.
+ */
+ .macro offset_ttbr1, ttbr, tmp
+#ifdef CONFIG_ARM64_VA_BITS_52
+ mrs_s \tmp, SYS_ID_AA64MMFR2_EL1
+ and \tmp, \tmp, #(0xf << ID_AA64MMFR2_LVA_SHIFT)
+ cbnz \tmp, .Lskipoffs_\@
+ orr \ttbr, \ttbr, #TTBR1_BADDR_4852_OFFSET
+.Lskipoffs_\@ :
+#endif
+ .endm
+
+/*
+ * Perform the reverse of offset_ttbr1.
+ * bic is used as it can cover the immediate value and, in future, won't need
+ * to be nop'ed out when dealing with 52-bit kernel VAs.
+ */
+ .macro restore_ttbr1, ttbr
+#ifdef CONFIG_ARM64_VA_BITS_52
+ bic \ttbr, \ttbr, #TTBR1_BADDR_4852_OFFSET
+#endif
+ .endm
+
+/*
+ * Arrange a physical address in a TTBR register, taking care of 52-bit
+ * addresses.
+ *
+ * phys: physical address, preserved
+ * ttbr: returns the TTBR value
+ */
+ .macro phys_to_ttbr, ttbr, phys
+#ifdef CONFIG_ARM64_PA_BITS_52
+ orr \ttbr, \phys, \phys, lsr #46
+ and \ttbr, \ttbr, #TTBR_BADDR_MASK_52
+#else
+ mov \ttbr, \phys
+#endif
+ .endm
+
+ .macro phys_to_pte, pte, phys
+#ifdef CONFIG_ARM64_PA_BITS_52
+ /*
+ * We assume \phys is 64K aligned and this is guaranteed by only
+ * supporting this configuration with 64K pages.
+ */
+ orr \pte, \phys, \phys, lsr #36
+ and \pte, \pte, #PTE_ADDR_MASK
+#else
+ mov \pte, \phys
+#endif
+ .endm
+
+ .macro pte_to_phys, phys, pte
+#ifdef CONFIG_ARM64_PA_BITS_52
+ ubfiz \phys, \pte, #(48 - 16 - 12), #16
+ bfxil \phys, \pte, #16, #32
+ lsl \phys, \phys, #16
+#else
+ and \phys, \pte, #PTE_ADDR_MASK
+#endif
+ .endm
+
+/*
+ * tcr_clear_errata_bits - Clear TCR bits that trigger an errata on this CPU.
+ */
+ .macro tcr_clear_errata_bits, tcr, tmp1, tmp2
+#ifdef CONFIG_FUJITSU_ERRATUM_010001
+ mrs \tmp1, midr_el1
+
+ mov_q \tmp2, MIDR_FUJITSU_ERRATUM_010001_MASK
+ and \tmp1, \tmp1, \tmp2
+ mov_q \tmp2, MIDR_FUJITSU_ERRATUM_010001
+ cmp \tmp1, \tmp2
+ b.ne 10f
+
+ mov_q \tmp2, TCR_CLEAR_FUJITSU_ERRATUM_010001
+ bic \tcr, \tcr, \tmp2
+10:
+#endif /* CONFIG_FUJITSU_ERRATUM_010001 */
+ .endm
+
+/**
+ * Errata workaround prior to disable MMU. Insert an ISB immediately prior
+ * to executing the MSR that will change SCTLR_ELn[M] from a value of 1 to 0.
+ */
+ .macro pre_disable_mmu_workaround
+#ifdef CONFIG_QCOM_FALKOR_ERRATUM_E1041
+ isb
+#endif
+ .endm
+
+ /*
+ * frame_push - Push @regcount callee saved registers to the stack,
+ * starting at x19, as well as x29/x30, and set x29 to
+ * the new value of sp. Add @extra bytes of stack space
+ * for locals.
+ */
+ .macro frame_push, regcount:req, extra
+ __frame st, \regcount, \extra
+ .endm
+
+ /*
+ * frame_pop - Pop the callee saved registers from the stack that were
+ * pushed in the most recent call to frame_push, as well
+ * as x29/x30 and any extra stack space that may have been
+ * allocated.
+ */
+ .macro frame_pop
+ __frame ld
+ .endm
+
+ .macro __frame_regs, reg1, reg2, op, num
+ .if .Lframe_regcount == \num
+ \op\()r \reg1, [sp, #(\num + 1) * 8]
+ .elseif .Lframe_regcount > \num
+ \op\()p \reg1, \reg2, [sp, #(\num + 1) * 8]
+ .endif
+ .endm
+
+ .macro __frame, op, regcount, extra=0
+ .ifc \op, st
+ .if (\regcount) < 0 || (\regcount) > 10
+ .error "regcount should be in the range [0 ... 10]"
+ .endif
+ .if ((\extra) % 16) != 0
+ .error "extra should be a multiple of 16 bytes"
+ .endif
+ .ifdef .Lframe_regcount
+ .if .Lframe_regcount != -1
+ .error "frame_push/frame_pop may not be nested"
+ .endif
+ .endif
+ .set .Lframe_regcount, \regcount
+ .set .Lframe_extra, \extra
+ .set .Lframe_local_offset, ((\regcount + 3) / 2) * 16
+ stp x29, x30, [sp, #-.Lframe_local_offset - .Lframe_extra]!
+ mov x29, sp
+ .endif
+
+ __frame_regs x19, x20, \op, 1
+ __frame_regs x21, x22, \op, 3
+ __frame_regs x23, x24, \op, 5
+ __frame_regs x25, x26, \op, 7
+ __frame_regs x27, x28, \op, 9
+
+ .ifc \op, ld
+ .if .Lframe_regcount == -1
+ .error "frame_push/frame_pop may not be nested"
+ .endif
+ ldp x29, x30, [sp], #.Lframe_local_offset + .Lframe_extra
+ .set .Lframe_regcount, -1
+ .endif
+ .endm
+
+/*
+ * Check whether to yield to another runnable task from kernel mode NEON code
+ * (which runs with preemption disabled).
+ *
+ * if_will_cond_yield_neon
+ * // pre-yield patchup code
+ * do_cond_yield_neon
+ * // post-yield patchup code
+ * endif_yield_neon <label>
+ *
+ * where <label> is optional, and marks the point where execution will resume
+ * after a yield has been performed. If omitted, execution resumes right after
+ * the endif_yield_neon invocation. Note that the entire sequence, including
+ * the provided patchup code, will be omitted from the image if
+ * CONFIG_PREEMPTION is not defined.
+ *
+ * As a convenience, in the case where no patchup code is required, the above
+ * sequence may be abbreviated to
+ *
+ * cond_yield_neon <label>
+ *
+ * Note that the patchup code does not support assembler directives that change
+ * the output section, any use of such directives is undefined.
+ *
+ * The yield itself consists of the following:
+ * - Check whether the preempt count is exactly 1 and a reschedule is also
+ * needed. If so, calling of preempt_enable() in kernel_neon_end() will
+ * trigger a reschedule. If it is not the case, yielding is pointless.
+ * - Disable and re-enable kernel mode NEON, and branch to the yield fixup
+ * code.
+ *
+ * This macro sequence may clobber all CPU state that is not guaranteed by the
+ * AAPCS to be preserved across an ordinary function call.
+ */
+
+ .macro cond_yield_neon, lbl
+ if_will_cond_yield_neon
+ do_cond_yield_neon
+ endif_yield_neon \lbl
+ .endm
+
+ .macro if_will_cond_yield_neon
+#ifdef CONFIG_PREEMPTION
+ get_current_task x0
+ ldr x0, [x0, #TSK_TI_PREEMPT]
+ sub x0, x0, #PREEMPT_DISABLE_OFFSET
+ cbz x0, .Lyield_\@
+ /* fall through to endif_yield_neon */
+ .subsection 1
+.Lyield_\@ :
+#else
+ .section ".discard.cond_yield_neon", "ax"
+#endif
+ .endm
+
+ .macro do_cond_yield_neon
+ bl kernel_neon_end
+ bl kernel_neon_begin
+ .endm
+
+ .macro endif_yield_neon, lbl
+ .ifnb \lbl
+ b \lbl
+ .else
+ b .Lyield_out_\@
+ .endif
+ .previous
+.Lyield_out_\@ :
+ .endm
+
+/*
+ * This macro emits a program property note section identifying
+ * architecture features which require special handling, mainly for
+ * use in assembly files included in the VDSO.
+ */
+
+#define NT_GNU_PROPERTY_TYPE_0 5
+#define GNU_PROPERTY_AARCH64_FEATURE_1_AND 0xc0000000
+
+#define GNU_PROPERTY_AARCH64_FEATURE_1_BTI (1U << 0)
+#define GNU_PROPERTY_AARCH64_FEATURE_1_PAC (1U << 1)
+
+#ifdef CONFIG_ARM64_BTI_KERNEL
+#define GNU_PROPERTY_AARCH64_FEATURE_1_DEFAULT \
+ ((GNU_PROPERTY_AARCH64_FEATURE_1_BTI | \
+ GNU_PROPERTY_AARCH64_FEATURE_1_PAC))
+#endif
+
+#ifdef GNU_PROPERTY_AARCH64_FEATURE_1_DEFAULT
+.macro emit_aarch64_feature_1_and, feat=GNU_PROPERTY_AARCH64_FEATURE_1_DEFAULT
+ .pushsection .note.gnu.property, "a"
+ .align 3
+ .long 2f - 1f
+ .long 6f - 3f
+ .long NT_GNU_PROPERTY_TYPE_0
+1: .string "GNU"
+2:
+ .align 3
+3: .long GNU_PROPERTY_AARCH64_FEATURE_1_AND
+ .long 5f - 4f
+4:
+ /*
+ * This is described with an array of char in the Linux API
+ * spec but the text and all other usage (including binutils,
+ * clang and GCC) treat this as a 32 bit value so no swizzling
+ * is required for big endian.
+ */
+ .long \feat
+5:
+ .align 3
+6:
+ .popsection
+.endm
+
+#else
+.macro emit_aarch64_feature_1_and, feat=0
+.endm
+
+#endif /* GNU_PROPERTY_AARCH64_FEATURE_1_DEFAULT */
+
+ .macro __mitigate_spectre_bhb_loop tmp
+#ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY
+alternative_cb spectre_bhb_patch_loop_iter
+ mov \tmp, #32 // Patched to correct the immediate
+alternative_cb_end
+.Lspectre_bhb_loop\@:
+ b . + 4
+ subs \tmp, \tmp, #1
+ b.ne .Lspectre_bhb_loop\@
+ sb
+#endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */
+ .endm
+
+ /* Save/restores x0-x3 to the stack */
+ .macro __mitigate_spectre_bhb_fw
+#ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY
+ stp x0, x1, [sp, #-16]!
+ stp x2, x3, [sp, #-16]!
+ mov w0, #ARM_SMCCC_ARCH_WORKAROUND_3
+alternative_cb smccc_patch_fw_mitigation_conduit
+ nop // Patched to SMC/HVC #0
+alternative_cb_end
+ ldp x2, x3, [sp], #16
+ ldp x0, x1, [sp], #16
+#endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */
+ .endm
+#endif /* __ASM_ASSEMBLER_H */