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-rw-r--r--payloads/libpayload/include/stdlib.h5
-rw-r--r--payloads/libpayload/libc/64bit_div.c141
-rw-r--r--payloads/libpayload/libc/Makefile.inc4
3 files changed, 150 insertions, 0 deletions
diff --git a/payloads/libpayload/include/stdlib.h b/payloads/libpayload/include/stdlib.h
index e571d18f0b..deb5e3dac4 100644
--- a/payloads/libpayload/include/stdlib.h
+++ b/payloads/libpayload/include/stdlib.h
@@ -225,4 +225,9 @@ void exit(int status) __attribute__ ((noreturn));
void qsort(void *aa, size_t n, size_t es, int (*cmp)(const void *, const void *));
char *getenv(const char*);
+uint64_t __umoddi3(uint64_t num, uint64_t den);
+uint64_t __udivdi3(uint64_t num, uint64_t den);
+uint64_t __ashldi3(uint64_t num, unsigned shift);
+uint64_t __lshrdi3(uint64_t num, unsigned shift);
+
#endif
diff --git a/payloads/libpayload/libc/64bit_div.c b/payloads/libpayload/libc/64bit_div.c
new file mode 100644
index 0000000000..615a2d8fdd
--- /dev/null
+++ b/payloads/libpayload/libc/64bit_div.c
@@ -0,0 +1,141 @@
+/*
+ * This file is part of the libpayload project.
+ *
+ * Copyright 2014 Google Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <libpayload-config.h>
+#include <stdlib.h>
+
+#ifndef CONFIG_LP_LITTLE_ENDIAN
+#error this code is for little endian only
+#endif
+
+union overlay64 {
+ uint64_t longw;
+ struct {
+ uint32_t lower;
+ uint32_t higher;
+ } words;
+};
+
+
+uint64_t __ashldi3(uint64_t num, unsigned shift)
+{
+ union overlay64 output;
+
+ output.longw = num;
+ if (shift >= 32) {
+ output.words.higher = output.words.lower << (shift - 32);
+ output.words.lower = 0;
+ } else {
+ if (!shift)
+ return num;
+ output.words.higher = (output.words.higher << shift) |
+ (output.words.lower >> (32 - shift));
+ output.words.lower = output.words.lower << shift;
+ }
+ return output.longw;
+}
+
+uint64_t __lshrdi3(uint64_t num, unsigned shift)
+{
+ union overlay64 output;
+
+ output.longw = num;
+ if (shift >= 32) {
+ output.words.lower = output.words.higher >> (shift - 32);
+ output.words.higher = 0;
+ } else {
+ if (!shift)
+ return num;
+ output.words.lower = output.words.lower >> shift |
+ (output.words.higher << (32 - shift));
+ output.words.higher = output.words.higher >> shift;
+ }
+ return output.longw;
+}
+
+#define MAX_32BIT_UINT ((((uint64_t)1) << 32) - 1)
+
+static uint64_t _64bit_divide(uint64_t dividend,
+ uint64_t divider, uint64_t *rem_p)
+{
+ uint64_t result = 0;
+
+ /*
+ * If divider is zero - let the rest of the system care about the
+ * exception.
+ */
+ if (!divider)
+ return 1/(uint32_t)divider;
+
+ /* As an optimization, let's not use 64 bit division unless we must. */
+ if (dividend <= MAX_32BIT_UINT) {
+ if (divider > MAX_32BIT_UINT) {
+ result = 0;
+ if (rem_p)
+ *rem_p = divider;
+ } else {
+ result = (uint32_t) dividend / (uint32_t) divider;
+ if (rem_p)
+ *rem_p = (uint32_t) dividend %
+ (uint32_t) divider;
+ }
+ return result;
+ }
+
+ while (divider <= dividend) {
+ uint64_t locald = divider;
+ uint64_t limit = __lshrdi3(dividend, 1);
+ int shifts = 0;
+
+ while (locald <= limit) {
+ shifts++;
+ locald = locald + locald;
+ }
+ result |= __ashldi3(1, shifts);
+ dividend -= locald;
+ }
+
+ if (rem_p)
+ *rem_p = dividend;
+
+ return result;
+}
+
+uint64_t __udivdi3(uint64_t num, uint64_t den)
+{
+ return _64bit_divide(num, den, NULL);
+}
+
+uint64_t __umoddi3(uint64_t num, uint64_t den)
+{
+ uint64_t v = 0;
+
+ _64bit_divide(num, den, &v);
+ return v;
+}
diff --git a/payloads/libpayload/libc/Makefile.inc b/payloads/libpayload/libc/Makefile.inc
index bd2a6f7595..b4f75a6cb5 100644
--- a/payloads/libpayload/libc/Makefile.inc
+++ b/payloads/libpayload/libc/Makefile.inc
@@ -41,3 +41,7 @@ libc-$(CONFIG_LP_LIBC) += coreboot.c
# should be moved to coreboot directory
libc-$(CONFIG_LP_LAR) += lar.c
+
+ifeq ($(CONFIG_LP_ARCH_MIPS),y)
+libc-$(CONFIG_LP_LIBC) += 64bit_div.c
+endif