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-rw-r--r--arch/csky/lib/Makefile6
-rw-r--r--arch/csky/lib/delay.c39
-rw-r--r--arch/csky/lib/error-inject.c10
-rw-r--r--arch/csky/lib/string.c134
-rw-r--r--arch/csky/lib/usercopy.c214
5 files changed, 403 insertions, 0 deletions
diff --git a/arch/csky/lib/Makefile b/arch/csky/lib/Makefile
new file mode 100644
index 000000000..d0ce6e2d7
--- /dev/null
+++ b/arch/csky/lib/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0-only
+lib-y := usercopy.o delay.o
+obj-$(CONFIG_FUNCTION_ERROR_INJECTION) += error-inject.o
+ifneq ($(CONFIG_HAVE_EFFICIENT_UNALIGNED_STRING_OPS), y)
+lib-y += string.o
+endif
diff --git a/arch/csky/lib/delay.c b/arch/csky/lib/delay.c
new file mode 100644
index 000000000..22570b079
--- /dev/null
+++ b/arch/csky/lib/delay.c
@@ -0,0 +1,39 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+
+void __delay(unsigned long loops)
+{
+ asm volatile (
+ "mov r0, r0\n"
+ "1:declt %0\n"
+ "bf 1b"
+ : "=r"(loops)
+ : "0"(loops));
+}
+EXPORT_SYMBOL(__delay);
+
+void __const_udelay(unsigned long xloops)
+{
+ unsigned long long loops;
+
+ loops = (unsigned long long)xloops * loops_per_jiffy * HZ;
+
+ __delay(loops >> 32);
+}
+EXPORT_SYMBOL(__const_udelay);
+
+void __udelay(unsigned long usecs)
+{
+ __const_udelay(usecs * 0x10C7UL); /* 2**32 / 1000000 (rounded up) */
+}
+EXPORT_SYMBOL(__udelay);
+
+void __ndelay(unsigned long nsecs)
+{
+ __const_udelay(nsecs * 0x5UL); /* 2**32 / 1000000000 (rounded up) */
+}
+EXPORT_SYMBOL(__ndelay);
diff --git a/arch/csky/lib/error-inject.c b/arch/csky/lib/error-inject.c
new file mode 100644
index 000000000..c15fb36fe
--- /dev/null
+++ b/arch/csky/lib/error-inject.c
@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/error-injection.h>
+#include <linux/kprobes.h>
+
+void override_function_with_return(struct pt_regs *regs)
+{
+ instruction_pointer_set(regs, regs->lr);
+}
+NOKPROBE_SYMBOL(override_function_with_return);
diff --git a/arch/csky/lib/string.c b/arch/csky/lib/string.c
new file mode 100644
index 000000000..d65626fca
--- /dev/null
+++ b/arch/csky/lib/string.c
@@ -0,0 +1,134 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * String functions optimized for hardware which doesn't
+ * handle unaligned memory accesses efficiently.
+ *
+ * Copyright (C) 2021 Matteo Croce
+ */
+
+#include <linux/types.h>
+#include <linux/module.h>
+
+/* Minimum size for a word copy to be convenient */
+#define BYTES_LONG sizeof(long)
+#define WORD_MASK (BYTES_LONG - 1)
+#define MIN_THRESHOLD (BYTES_LONG * 2)
+
+/* convenience union to avoid cast between different pointer types */
+union types {
+ u8 *as_u8;
+ unsigned long *as_ulong;
+ uintptr_t as_uptr;
+};
+
+union const_types {
+ const u8 *as_u8;
+ unsigned long *as_ulong;
+ uintptr_t as_uptr;
+};
+
+void *memcpy(void *dest, const void *src, size_t count)
+{
+ union const_types s = { .as_u8 = src };
+ union types d = { .as_u8 = dest };
+ int distance = 0;
+
+ if (count < MIN_THRESHOLD)
+ goto copy_remainder;
+
+ /* Copy a byte at time until destination is aligned. */
+ for (; d.as_uptr & WORD_MASK; count--)
+ *d.as_u8++ = *s.as_u8++;
+
+ distance = s.as_uptr & WORD_MASK;
+
+ if (distance) {
+ unsigned long last, next;
+
+ /*
+ * s is distance bytes ahead of d, and d just reached
+ * the alignment boundary. Move s backward to word align it
+ * and shift data to compensate for distance, in order to do
+ * word-by-word copy.
+ */
+ s.as_u8 -= distance;
+
+ next = s.as_ulong[0];
+ for (; count >= BYTES_LONG; count -= BYTES_LONG) {
+ last = next;
+ next = s.as_ulong[1];
+
+ d.as_ulong[0] = last >> (distance * 8) |
+ next << ((BYTES_LONG - distance) * 8);
+
+ d.as_ulong++;
+ s.as_ulong++;
+ }
+
+ /* Restore s with the original offset. */
+ s.as_u8 += distance;
+ } else {
+ /*
+ * If the source and dest lower bits are the same, do a simple
+ * 32/64 bit wide copy.
+ */
+ for (; count >= BYTES_LONG; count -= BYTES_LONG)
+ *d.as_ulong++ = *s.as_ulong++;
+ }
+
+copy_remainder:
+ while (count--)
+ *d.as_u8++ = *s.as_u8++;
+
+ return dest;
+}
+EXPORT_SYMBOL(memcpy);
+
+/*
+ * Simply check if the buffer overlaps an call memcpy() in case,
+ * otherwise do a simple one byte at time backward copy.
+ */
+void *memmove(void *dest, const void *src, size_t count)
+{
+ if (dest < src || src + count <= dest)
+ return memcpy(dest, src, count);
+
+ if (dest > src) {
+ const char *s = src + count;
+ char *tmp = dest + count;
+
+ while (count--)
+ *--tmp = *--s;
+ }
+ return dest;
+}
+EXPORT_SYMBOL(memmove);
+
+void *memset(void *s, int c, size_t count)
+{
+ union types dest = { .as_u8 = s };
+
+ if (count >= MIN_THRESHOLD) {
+ unsigned long cu = (unsigned long)c;
+
+ /* Compose an ulong with 'c' repeated 4/8 times */
+ cu |= cu << 8;
+ cu |= cu << 16;
+ /* Suppress warning on 32 bit machines */
+ cu |= (cu << 16) << 16;
+
+ for (; count && dest.as_uptr & WORD_MASK; count--)
+ *dest.as_u8++ = c;
+
+ /* Copy using the largest size allowed */
+ for (; count >= BYTES_LONG; count -= BYTES_LONG)
+ *dest.as_ulong++ = cu;
+ }
+
+ /* copy the remainder */
+ while (count--)
+ *dest.as_u8++ = c;
+
+ return s;
+}
+EXPORT_SYMBOL(memset);
diff --git a/arch/csky/lib/usercopy.c b/arch/csky/lib/usercopy.c
new file mode 100644
index 000000000..3c01c5442
--- /dev/null
+++ b/arch/csky/lib/usercopy.c
@@ -0,0 +1,214 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/uaccess.h>
+#include <linux/types.h>
+
+unsigned long raw_copy_from_user(void *to, const void *from,
+ unsigned long n)
+{
+ int tmp, nsave;
+
+ __asm__ __volatile__(
+ "0: cmpnei %1, 0 \n"
+ " bf 7f \n"
+ " mov %3, %1 \n"
+ " or %3, %2 \n"
+ " andi %3, 3 \n"
+ " cmpnei %3, 0 \n"
+ " bf 1f \n"
+ " br 5f \n"
+ "1: cmplti %0, 16 \n"
+ " bt 3f \n"
+ "2: ldw %3, (%2, 0) \n"
+ "10: ldw %4, (%2, 4) \n"
+ " stw %3, (%1, 0) \n"
+ " stw %4, (%1, 4) \n"
+ "11: ldw %3, (%2, 8) \n"
+ "12: ldw %4, (%2, 12) \n"
+ " stw %3, (%1, 8) \n"
+ " stw %4, (%1, 12) \n"
+ " addi %2, 16 \n"
+ " addi %1, 16 \n"
+ " subi %0, 16 \n"
+ " br 1b \n"
+ "3: cmplti %0, 4 \n"
+ " bt 5f \n"
+ "4: ldw %3, (%2, 0) \n"
+ " stw %3, (%1, 0) \n"
+ " addi %2, 4 \n"
+ " addi %1, 4 \n"
+ " subi %0, 4 \n"
+ " br 3b \n"
+ "5: cmpnei %0, 0 \n"
+ " bf 7f \n"
+ "6: ldb %3, (%2, 0) \n"
+ " stb %3, (%1, 0) \n"
+ " addi %2, 1 \n"
+ " addi %1, 1 \n"
+ " subi %0, 1 \n"
+ " br 5b \n"
+ "8: stw %3, (%1, 0) \n"
+ " subi %0, 4 \n"
+ " bf 7f \n"
+ "9: subi %0, 8 \n"
+ " bf 7f \n"
+ "13: stw %3, (%1, 8) \n"
+ " subi %0, 12 \n"
+ " bf 7f \n"
+ ".section __ex_table, \"a\" \n"
+ ".align 2 \n"
+ ".long 2b, 7f \n"
+ ".long 4b, 7f \n"
+ ".long 6b, 7f \n"
+ ".long 10b, 8b \n"
+ ".long 11b, 9b \n"
+ ".long 12b,13b \n"
+ ".previous \n"
+ "7: \n"
+ : "=r"(n), "=r"(to), "=r"(from), "=r"(nsave),
+ "=r"(tmp)
+ : "0"(n), "1"(to), "2"(from)
+ : "memory");
+
+ return n;
+}
+EXPORT_SYMBOL(raw_copy_from_user);
+
+unsigned long raw_copy_to_user(void *to, const void *from,
+ unsigned long n)
+{
+ int w0, w1, w2, w3;
+
+ __asm__ __volatile__(
+ "0: cmpnei %1, 0 \n"
+ " bf 8f \n"
+ " mov %3, %1 \n"
+ " or %3, %2 \n"
+ " andi %3, 3 \n"
+ " cmpnei %3, 0 \n"
+ " bf 1f \n"
+ " br 5f \n"
+ "1: cmplti %0, 16 \n" /* 4W */
+ " bt 3f \n"
+ " ldw %3, (%2, 0) \n"
+ " ldw %4, (%2, 4) \n"
+ " ldw %5, (%2, 8) \n"
+ " ldw %6, (%2, 12) \n"
+ "2: stw %3, (%1, 0) \n"
+ "9: stw %4, (%1, 4) \n"
+ "10: stw %5, (%1, 8) \n"
+ "11: stw %6, (%1, 12) \n"
+ " addi %2, 16 \n"
+ " addi %1, 16 \n"
+ " subi %0, 16 \n"
+ " br 1b \n"
+ "3: cmplti %0, 4 \n" /* 1W */
+ " bt 5f \n"
+ " ldw %3, (%2, 0) \n"
+ "4: stw %3, (%1, 0) \n"
+ " addi %2, 4 \n"
+ " addi %1, 4 \n"
+ " subi %0, 4 \n"
+ " br 3b \n"
+ "5: cmpnei %0, 0 \n" /* 1B */
+ " bf 13f \n"
+ " ldb %3, (%2, 0) \n"
+ "6: stb %3, (%1, 0) \n"
+ " addi %2, 1 \n"
+ " addi %1, 1 \n"
+ " subi %0, 1 \n"
+ " br 5b \n"
+ "7: subi %0, 4 \n"
+ "8: subi %0, 4 \n"
+ "12: subi %0, 4 \n"
+ " br 13f \n"
+ ".section __ex_table, \"a\" \n"
+ ".align 2 \n"
+ ".long 2b, 13f \n"
+ ".long 4b, 13f \n"
+ ".long 6b, 13f \n"
+ ".long 9b, 12b \n"
+ ".long 10b, 8b \n"
+ ".long 11b, 7b \n"
+ ".previous \n"
+ "13: \n"
+ : "=r"(n), "=r"(to), "=r"(from), "=r"(w0),
+ "=r"(w1), "=r"(w2), "=r"(w3)
+ : "0"(n), "1"(to), "2"(from)
+ : "memory");
+
+ return n;
+}
+EXPORT_SYMBOL(raw_copy_to_user);
+
+/*
+ * __clear_user: - Zero a block of memory in user space, with less checking.
+ * @to: Destination address, in user space.
+ * @n: Number of bytes to zero.
+ *
+ * Zero a block of memory in user space. Caller must check
+ * the specified block with access_ok() before calling this function.
+ *
+ * Returns number of bytes that could not be cleared.
+ * On success, this will be zero.
+ */
+unsigned long
+__clear_user(void __user *to, unsigned long n)
+{
+ int data, value, tmp;
+
+ __asm__ __volatile__(
+ "0: cmpnei %1, 0 \n"
+ " bf 7f \n"
+ " mov %3, %1 \n"
+ " andi %3, 3 \n"
+ " cmpnei %3, 0 \n"
+ " bf 1f \n"
+ " br 5f \n"
+ "1: cmplti %0, 32 \n" /* 4W */
+ " bt 3f \n"
+ "8: stw %2, (%1, 0) \n"
+ "10: stw %2, (%1, 4) \n"
+ "11: stw %2, (%1, 8) \n"
+ "12: stw %2, (%1, 12) \n"
+ "13: stw %2, (%1, 16) \n"
+ "14: stw %2, (%1, 20) \n"
+ "15: stw %2, (%1, 24) \n"
+ "16: stw %2, (%1, 28) \n"
+ " addi %1, 32 \n"
+ " subi %0, 32 \n"
+ " br 1b \n"
+ "3: cmplti %0, 4 \n" /* 1W */
+ " bt 5f \n"
+ "4: stw %2, (%1, 0) \n"
+ " addi %1, 4 \n"
+ " subi %0, 4 \n"
+ " br 3b \n"
+ "5: cmpnei %0, 0 \n" /* 1B */
+ "9: bf 7f \n"
+ "6: stb %2, (%1, 0) \n"
+ " addi %1, 1 \n"
+ " subi %0, 1 \n"
+ " br 5b \n"
+ ".section __ex_table,\"a\" \n"
+ ".align 2 \n"
+ ".long 8b, 9b \n"
+ ".long 10b, 9b \n"
+ ".long 11b, 9b \n"
+ ".long 12b, 9b \n"
+ ".long 13b, 9b \n"
+ ".long 14b, 9b \n"
+ ".long 15b, 9b \n"
+ ".long 16b, 9b \n"
+ ".long 4b, 9b \n"
+ ".long 6b, 9b \n"
+ ".previous \n"
+ "7: \n"
+ : "=r"(n), "=r" (data), "=r"(value), "=r"(tmp)
+ : "0"(n), "1"(to), "2"(0)
+ : "memory");
+
+ return n;
+}
+EXPORT_SYMBOL(__clear_user);