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-rw-r--r--arch/sh/lib/copy_page.S390
1 files changed, 390 insertions, 0 deletions
diff --git a/arch/sh/lib/copy_page.S b/arch/sh/lib/copy_page.S
new file mode 100644
index 000000000..d4e9d18ce
--- /dev/null
+++ b/arch/sh/lib/copy_page.S
@@ -0,0 +1,390 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * copy_page, __copy_user_page, __copy_user implementation of SuperH
+ *
+ * Copyright (C) 2001 Niibe Yutaka & Kaz Kojima
+ * Copyright (C) 2002 Toshinobu Sugioka
+ * Copyright (C) 2006 Paul Mundt
+ */
+#include <linux/linkage.h>
+#include <asm/page.h>
+
+/*
+ * copy_page
+ * @to: P1 address
+ * @from: P1 address
+ *
+ * void copy_page(void *to, void *from)
+ */
+
+/*
+ * r0, r1, r2, r3, r4, r5, r6, r7 --- scratch
+ * r8 --- from + PAGE_SIZE
+ * r9 --- not used
+ * r10 --- to
+ * r11 --- from
+ */
+ENTRY(copy_page)
+ mov.l r8,@-r15
+ mov.l r10,@-r15
+ mov.l r11,@-r15
+ mov r4,r10
+ mov r5,r11
+ mov r5,r8
+ mov #(PAGE_SIZE >> 10), r0
+ shll8 r0
+ shll2 r0
+ add r0,r8
+ !
+1: mov.l @r11+,r0
+ mov.l @r11+,r1
+ mov.l @r11+,r2
+ mov.l @r11+,r3
+ mov.l @r11+,r4
+ mov.l @r11+,r5
+ mov.l @r11+,r6
+ mov.l @r11+,r7
+#if defined(CONFIG_CPU_SH4)
+ movca.l r0,@r10
+#else
+ mov.l r0,@r10
+#endif
+ add #32,r10
+ mov.l r7,@-r10
+ mov.l r6,@-r10
+ mov.l r5,@-r10
+ mov.l r4,@-r10
+ mov.l r3,@-r10
+ mov.l r2,@-r10
+ mov.l r1,@-r10
+ cmp/eq r11,r8
+ bf/s 1b
+ add #28,r10
+ !
+ mov.l @r15+,r11
+ mov.l @r15+,r10
+ mov.l @r15+,r8
+ rts
+ nop
+
+/*
+ * __kernel_size_t __copy_user(void *to, const void *from, __kernel_size_t n);
+ * Return the number of bytes NOT copied
+ */
+#define EX(...) \
+ 9999: __VA_ARGS__ ; \
+ .section __ex_table, "a"; \
+ .long 9999b, 6000f ; \
+ .previous
+#define EX_NO_POP(...) \
+ 9999: __VA_ARGS__ ; \
+ .section __ex_table, "a"; \
+ .long 9999b, 6005f ; \
+ .previous
+ENTRY(__copy_user)
+ ! Check if small number of bytes
+ mov #11,r0
+ mov r4,r3
+ cmp/gt r0,r6 ! r6 (len) > r0 (11)
+ bf/s .L_cleanup_loop_no_pop
+ add r6,r3 ! last destination address
+
+ ! Calculate bytes needed to align to src
+ mov.l r11,@-r15
+ neg r5,r0
+ mov.l r10,@-r15
+ add #4,r0
+ mov.l r9,@-r15
+ and #3,r0
+ mov.l r8,@-r15
+ tst r0,r0
+ bt 2f
+
+1:
+ ! Copy bytes to long word align src
+EX( mov.b @r5+,r1 )
+ dt r0
+ add #-1,r6
+EX( mov.b r1,@r4 )
+ bf/s 1b
+ add #1,r4
+
+ ! Jump to appropriate routine depending on dest
+2: mov #3,r1
+ mov r6, r2
+ and r4,r1
+ shlr2 r2
+ shll2 r1
+ mova .L_jump_tbl,r0
+ mov.l @(r0,r1),r1
+ jmp @r1
+ nop
+
+ .align 2
+.L_jump_tbl:
+ .long .L_dest00
+ .long .L_dest01
+ .long .L_dest10
+ .long .L_dest11
+
+/*
+ * Come here if there are less than 12 bytes to copy
+ *
+ * Keep the branch target close, so the bf/s callee doesn't overflow
+ * and result in a more expensive branch being inserted. This is the
+ * fast-path for small copies, the jump via the jump table will hit the
+ * default slow-path cleanup. -PFM.
+ */
+.L_cleanup_loop_no_pop:
+ tst r6,r6 ! Check explicitly for zero
+ bt 1f
+
+2:
+EX_NO_POP( mov.b @r5+,r0 )
+ dt r6
+EX_NO_POP( mov.b r0,@r4 )
+ bf/s 2b
+ add #1,r4
+
+1: mov #0,r0 ! normal return
+5000:
+
+# Exception handler:
+.section .fixup, "ax"
+6005:
+ mov.l 8000f,r1
+ mov r3,r0
+ jmp @r1
+ sub r4,r0
+ .align 2
+8000: .long 5000b
+
+.previous
+ rts
+ nop
+
+! Destination = 00
+
+.L_dest00:
+ ! Skip the large copy for small transfers
+ mov #(32+32-4), r0
+ cmp/gt r6, r0 ! r0 (60) > r6 (len)
+ bt 1f
+
+ ! Align dest to a 32 byte boundary
+ neg r4,r0
+ add #0x20, r0
+ and #0x1f, r0
+ tst r0, r0
+ bt 2f
+
+ sub r0, r6
+ shlr2 r0
+3:
+EX( mov.l @r5+,r1 )
+ dt r0
+EX( mov.l r1,@r4 )
+ bf/s 3b
+ add #4,r4
+
+2:
+EX( mov.l @r5+,r0 )
+EX( mov.l @r5+,r1 )
+EX( mov.l @r5+,r2 )
+EX( mov.l @r5+,r7 )
+EX( mov.l @r5+,r8 )
+EX( mov.l @r5+,r9 )
+EX( mov.l @r5+,r10 )
+EX( mov.l @r5+,r11 )
+#ifdef CONFIG_CPU_SH4
+EX( movca.l r0,@r4 )
+#else
+EX( mov.l r0,@r4 )
+#endif
+ add #-32, r6
+EX( mov.l r1,@(4,r4) )
+ mov #32, r0
+EX( mov.l r2,@(8,r4) )
+ cmp/gt r6, r0 ! r0 (32) > r6 (len)
+EX( mov.l r7,@(12,r4) )
+EX( mov.l r8,@(16,r4) )
+EX( mov.l r9,@(20,r4) )
+EX( mov.l r10,@(24,r4) )
+EX( mov.l r11,@(28,r4) )
+ bf/s 2b
+ add #32,r4
+
+1: mov r6, r0
+ shlr2 r0
+ tst r0, r0
+ bt .L_cleanup
+1:
+EX( mov.l @r5+,r1 )
+ dt r0
+EX( mov.l r1,@r4 )
+ bf/s 1b
+ add #4,r4
+
+ bra .L_cleanup
+ nop
+
+! Destination = 10
+
+.L_dest10:
+ mov r2,r7
+ shlr2 r7
+ shlr r7
+ tst r7,r7
+ mov #7,r0
+ bt/s 1f
+ and r0,r2
+2:
+ dt r7
+#ifdef CONFIG_CPU_LITTLE_ENDIAN
+EX( mov.l @r5+,r0 )
+EX( mov.l @r5+,r1 )
+EX( mov.l @r5+,r8 )
+EX( mov.l @r5+,r9 )
+EX( mov.l @r5+,r10 )
+EX( mov.w r0,@r4 )
+ add #2,r4
+ xtrct r1,r0
+ xtrct r8,r1
+ xtrct r9,r8
+ xtrct r10,r9
+
+EX( mov.l r0,@r4 )
+EX( mov.l r1,@(4,r4) )
+EX( mov.l r8,@(8,r4) )
+EX( mov.l r9,@(12,r4) )
+
+EX( mov.l @r5+,r1 )
+EX( mov.l @r5+,r8 )
+EX( mov.l @r5+,r0 )
+ xtrct r1,r10
+ xtrct r8,r1
+ xtrct r0,r8
+ shlr16 r0
+EX( mov.l r10,@(16,r4) )
+EX( mov.l r1,@(20,r4) )
+EX( mov.l r8,@(24,r4) )
+EX( mov.w r0,@(28,r4) )
+ bf/s 2b
+ add #30,r4
+#else
+EX( mov.l @(28,r5),r0 )
+EX( mov.l @(24,r5),r8 )
+EX( mov.l @(20,r5),r9 )
+EX( mov.l @(16,r5),r10 )
+EX( mov.w r0,@(30,r4) )
+ add #-2,r4
+ xtrct r8,r0
+ xtrct r9,r8
+ xtrct r10,r9
+EX( mov.l r0,@(28,r4) )
+EX( mov.l r8,@(24,r4) )
+EX( mov.l r9,@(20,r4) )
+
+EX( mov.l @(12,r5),r0 )
+EX( mov.l @(8,r5),r8 )
+ xtrct r0,r10
+EX( mov.l @(4,r5),r9 )
+ mov.l r10,@(16,r4)
+EX( mov.l @r5,r10 )
+ xtrct r8,r0
+ xtrct r9,r8
+ xtrct r10,r9
+EX( mov.l r0,@(12,r4) )
+EX( mov.l r8,@(8,r4) )
+ swap.w r10,r0
+EX( mov.l r9,@(4,r4) )
+EX( mov.w r0,@(2,r4) )
+
+ add #32,r5
+ bf/s 2b
+ add #34,r4
+#endif
+ tst r2,r2
+ bt .L_cleanup
+
+1: ! Read longword, write two words per iteration
+EX( mov.l @r5+,r0 )
+ dt r2
+#ifdef CONFIG_CPU_LITTLE_ENDIAN
+EX( mov.w r0,@r4 )
+ shlr16 r0
+EX( mov.w r0,@(2,r4) )
+#else
+EX( mov.w r0,@(2,r4) )
+ shlr16 r0
+EX( mov.w r0,@r4 )
+#endif
+ bf/s 1b
+ add #4,r4
+
+ bra .L_cleanup
+ nop
+
+! Destination = 01 or 11
+
+.L_dest01:
+.L_dest11:
+ ! Read longword, write byte, word, byte per iteration
+EX( mov.l @r5+,r0 )
+ dt r2
+#ifdef CONFIG_CPU_LITTLE_ENDIAN
+EX( mov.b r0,@r4 )
+ shlr8 r0
+ add #1,r4
+EX( mov.w r0,@r4 )
+ shlr16 r0
+EX( mov.b r0,@(2,r4) )
+ bf/s .L_dest01
+ add #3,r4
+#else
+EX( mov.b r0,@(3,r4) )
+ shlr8 r0
+ swap.w r0,r7
+EX( mov.b r7,@r4 )
+ add #1,r4
+EX( mov.w r0,@r4 )
+ bf/s .L_dest01
+ add #3,r4
+#endif
+
+! Cleanup last few bytes
+.L_cleanup:
+ mov r6,r0
+ and #3,r0
+ tst r0,r0
+ bt .L_exit
+ mov r0,r6
+
+.L_cleanup_loop:
+EX( mov.b @r5+,r0 )
+ dt r6
+EX( mov.b r0,@r4 )
+ bf/s .L_cleanup_loop
+ add #1,r4
+
+.L_exit:
+ mov #0,r0 ! normal return
+
+5000:
+
+# Exception handler:
+.section .fixup, "ax"
+6000:
+ mov.l 8000f,r1
+ mov r3,r0
+ jmp @r1
+ sub r4,r0
+ .align 2
+8000: .long 5000b
+
+.previous
+ mov.l @r15+,r8
+ mov.l @r15+,r9
+ mov.l @r15+,r10
+ rts
+ mov.l @r15+,r11
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