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-rw-r--r--arch/arm/include/asm/assembler.h239
1 files changed, 233 insertions, 6 deletions
diff --git a/arch/arm/include/asm/assembler.h b/arch/arm/include/asm/assembler.h
index 6116e4893c..5db0f692ee 100644
--- a/arch/arm/include/asm/assembler.h
+++ b/arch/arm/include/asm/assembler.h
@@ -1,12 +1,9 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* SPDX-FileCopyrightText: 1996-2000 Russell King */
+
/*
* arch/arm/include/asm/assembler.h
*
- * Copyright (C) 1996-2000 Russell King
- *
- * 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.
- *
* This file contains arm architecture specific defines
* for the different processors.
*
@@ -114,3 +111,233 @@
.align 3; \
.long 9999b,9001f; \
.previous
+
+
+/*
+ * 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
+
+#ifdef CONFIG_CPU_64
+/*
+ * 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
+
+#else
+
+ .macro __adldst_l, op, reg, sym, tmp, c
+ .if __LINUX_ARM_ARCH__ < 7
+ ldr\c \tmp, .La\@
+ .subsection 1
+ .align 2
+.La\@: .long \sym - .Lpc\@
+ .previous
+ .else
+ .ifnb \c
+ THUMB( ittt \c )
+ .endif
+ movw\c \tmp, #:lower16:\sym - .Lpc\@
+ movt\c \tmp, #:upper16:\sym - .Lpc\@
+ .endif
+
+#ifndef CONFIG_THUMB2_BAREBOX
+ .set .Lpc\@, . + 8 // PC bias
+ .ifc \op, add
+ add\c \reg, \tmp, pc
+ .else
+ \op\c \reg, [pc, \tmp]
+ .endif
+#else
+.Lb\@: add\c \tmp, \tmp, pc
+ /*
+ * In Thumb-2 builds, the PC bias depends on whether we are currently
+ * emitting into a .arm or a .thumb section. The size of the add opcode
+ * above will be 2 bytes when emitting in Thumb mode and 4 bytes when
+ * emitting in ARM mode, so let's use this to account for the bias.
+ */
+ .set .Lpc\@, . + (. - .Lb\@)
+
+ .ifnc \op, add
+ \op\c \reg, [\tmp]
+ .endif
+#endif
+ .endm
+
+ /*
+ * mov_l - move a constant value or [relocated] address into a register
+ */
+ .macro mov_l, dst:req, imm:req, cond
+ .if __LINUX_ARM_ARCH__ < 7
+ ldr\cond \dst, =\imm
+ .else
+ movw\cond \dst, #:lower16:\imm
+ movt\cond \dst, #:upper16:\imm
+ .endif
+ .endm
+
+ /*
+ * adr_l - adr pseudo-op with unlimited range
+ *
+ * @dst: destination register
+ * @sym: name of the symbol
+ * @cond: conditional opcode suffix
+ */
+ .macro adr_l, dst:req, sym:req, cond
+ __adldst_l add, \dst, \sym, \dst, \cond
+ .endm
+
+ /*
+ * ldr_l - ldr <literal> pseudo-op with unlimited range
+ *
+ * @dst: destination register
+ * @sym: name of the symbol
+ * @cond: conditional opcode suffix
+ */
+ .macro ldr_l, dst:req, sym:req, cond
+ __adldst_l ldr, \dst, \sym, \dst, \cond
+ .endm
+
+ /*
+ * str_l - str <literal> pseudo-op with unlimited range
+ *
+ * @src: source register
+ * @sym: name of the symbol
+ * @tmp: mandatory scratch register
+ * @cond: conditional opcode suffix
+ */
+ .macro str_l, src:req, sym:req, tmp:req, cond
+ __adldst_l str, \src, \sym, \tmp, \cond
+ .endm
+
+ .macro __ldst_va, op, reg, tmp, sym, cond, offset
+#if __LINUX_ARM_ARCH__ >= 7 || \
+ (defined(MODULE) && defined(CONFIG_ARM_MODULE_PLTS))
+ mov_l \tmp, \sym, \cond
+#else
+ /*
+ * Avoid a literal load, by emitting a sequence of ADD/LDR instructions
+ * with the appropriate relocations. The combined sequence has a range
+ * of -/+ 256 MiB, which should be sufficient for the core kernel and
+ * for modules loaded into the module region.
+ */
+ .globl \sym
+ .reloc .L0_\@, R_ARM_ALU_PC_G0_NC, \sym
+ .reloc .L1_\@, R_ARM_ALU_PC_G1_NC, \sym
+ .reloc .L2_\@, R_ARM_LDR_PC_G2, \sym
+.L0_\@: sub\cond \tmp, pc, #8 - \offset
+.L1_\@: sub\cond \tmp, \tmp, #4 - \offset
+.L2_\@:
+#endif
+ \op\cond \reg, [\tmp, #\offset]
+ .endm
+
+ /*
+ * ldr_va - load a 32-bit word from the virtual address of \sym
+ */
+ .macro ldr_va, rd:req, sym:req, cond, tmp, offset=0
+ .ifnb \tmp
+ __ldst_va ldr, \rd, \tmp, \sym, \cond, \offset
+ .else
+ __ldst_va ldr, \rd, \rd, \sym, \cond, \offset
+ .endif
+ .endm
+
+ /*
+ * str_va - store a 32-bit word to the virtual address of \sym
+ */
+ .macro str_va, rn:req, sym:req, tmp:req, cond
+ __ldst_va str, \rn, \tmp, \sym, \cond, 0
+ .endm
+
+ /*
+ * ldr_this_cpu - Load a 32-bit word from the per-CPU variable 'sym'
+ * into register 'rd', which may be the stack pointer,
+ * using 't1' and 't2' as general temp registers. These
+ * are permitted to overlap with 'rd' if != sp
+ */
+ .macro ldr_this_cpu, rd:req, sym:req, t1:req, t2:req
+ ldr_va \rd, \sym, tmp=\t1
+ .endm
+
+ /*
+ * rev_l - byte-swap a 32-bit value
+ *
+ * @val: source/destination register
+ * @tmp: scratch register
+ */
+ .macro rev_l, val:req, tmp:req
+ .if __LINUX_ARM_ARCH__ < 6
+ eor \tmp, \val, \val, ror #16
+ bic \tmp, \tmp, #0x00ff0000
+ mov \val, \val, ror #8
+ eor \val, \val, \tmp, lsr #8
+ .else
+ rev \val, \val
+ .endif
+ .endm
+
+ /*
+ * bl_r - branch and link to register
+ *
+ * @dst: target to branch to
+ * @c: conditional opcode suffix
+ */
+ .macro bl_r, dst:req, c
+ .if __LINUX_ARM_ARCH__ < 6
+ mov\c lr, pc
+ mov\c pc, \dst
+ .else
+ blx\c \dst
+ .endif
+ .endm
+#endif