+From: Wu Zhangjin <wuzj@lemote.com>
+
+the gcc 4.4 support for MIPS mostly refer to this PATCH:
+http://www.nabble.com/-PATCH--MIPS:-Handle-removal-of-%27h%27-constraint-in-GCC-4.4-td22192768.html
+but have been tuned a little.
+
+because only gcc 4.4 have loongson-specific support, so, we need to
+choose the suitable -march argument for gcc <= 4.3 and gcc >= 4.4, and
+we also need to consider use -march=loongson2e and -march=loongson2f for
+loongson2e and loongson2f respectively. this is handled by adding two
+new kernel options: CPU_LOONGSON2E and CPU_LOONGSON2F(thanks for the
+solutin provided by ZhangLe).
+
+I have tested it on FuLoong(2f) in 32bit and 64bit with gcc-4.4 and
+gcc-4.3. so, basically, it works.
+
+Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
+---
+ arch/mips/Makefile | 9 +++++-
+ arch/mips/include/asm/compiler.h | 10 ++++++
+ arch/mips/include/asm/delay.h | 58 +++++++++++++++++++++++++------------
+ 3 files changed, 57 insertions(+), 20 deletions(-)
+
+diff --git a/arch/mips/Makefile b/arch/mips/Makefile
+index a25c2e5..1ee5504 100644
+--- a/arch/mips/Makefile
++++ b/arch/mips/Makefile
+@@ -120,7 +120,14 @@ cflags-$(CONFIG_CPU_R4300) += -march=r4300 -Wa,--trap
+ cflags-$(CONFIG_CPU_VR41XX) += -march=r4100 -Wa,--trap
+ cflags-$(CONFIG_CPU_R4X00) += -march=r4600 -Wa,--trap
+ cflags-$(CONFIG_CPU_TX49XX) += -march=r4600 -Wa,--trap
+-cflags-$(CONFIG_CPU_LOONGSON2) += -march=r4600 -Wa,--trap
++
++# only gcc >= 4.4 have the loongson-specific support
++cflags-$(CONFIG_CPU_LOONGSON2) += -Wa,--trap
++cflags-$(CONFIG_CPU_LOONGSON2E) += $(shell if [ $(call cc-version) -lt 0440 ] ; then \
++ echo $(call cc-option,-march=r4600); else echo $(call cc-option,-march=loongson2e); fi ;)
++cflags-$(CONFIG_CPU_LOONGSON2F) += $(shell if [ $(call cc-version) -lt 0440 ] ; then \
++ echo $(call cc-option,-march=r4600); else echo $(call cc-option,-march=loongson2f); fi ;)
++
+ cflags-$(CONFIG_CPU_MIPS32_R1) += $(call cc-option,-march=mips32,-mips32 -U_MIPS_ISA -D_MIPS_ISA=_MIPS_ISA_MIPS32) \
+ -Wa,-mips32 -Wa,--trap
+ cflags-$(CONFIG_CPU_MIPS32_R2) += $(call cc-option,-march=mips32r2,-mips32r2 -U_MIPS_ISA -D_MIPS_ISA=_MIPS_ISA_MIPS32) \
+diff --git a/arch/mips/include/asm/compiler.h b/arch/mips/include/asm/compiler.h
+index 71f5c5c..95256a8 100644
+--- a/arch/mips/include/asm/compiler.h
++++ b/arch/mips/include/asm/compiler.h
+@@ -1,5 +1,6 @@
+ /*
+ * Copyright (C) 2004, 2007 Maciej W. Rozycki
++ * Copyright (C) 2009 Wu Zhangjin, wuzj@lemote.com
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+@@ -16,4 +17,13 @@
+ #define GCC_REG_ACCUM "accum"
+ #endif
+
++#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 4)
++#define GCC_NO_H_CONSTRAINT
++#ifdef CONFIG_64BIT
++typedef unsigned int uintx_t __attribute__((mode(TI)));
++#else
++typedef u64 uintx_t;
++#endif
++#endif
++
+ #endif /* _ASM_COMPILER_H */
+diff --git a/arch/mips/include/asm/delay.h b/arch/mips/include/asm/delay.h
+index b0bccd2..00d7969 100644
+--- a/arch/mips/include/asm/delay.h
++++ b/arch/mips/include/asm/delay.h
+@@ -7,6 +7,7 @@
+ * Copyright (C) 1995 - 2000, 01, 03 by Ralf Baechle
+ * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
+ * Copyright (C) 2007 Maciej W. Rozycki
++ * Copyright (C) 2009 Wu Zhangjin, wuzj@lemote.com
+ */
+ #ifndef _ASM_DELAY_H
+ #define _ASM_DELAY_H
+@@ -48,6 +49,43 @@ static inline void __delay(unsigned long loops)
+ : "0" (loops), "r" (1));
+ }
+
++/*
++ * convert usecs to loops
++ *
++ * handle removal of 'h' constraint in GCC 4.4
++ */
++
++#ifndef GCC_NO_H_CONSTRAINT /* gcc <= 4.3 */
++static inline unsigned long __usecs_to_loops(unsigned long usecs,
++ unsigned long lpj)
++{
++ unsigned long hi, lo;
++
++ if (sizeof(long) == 4)
++ __asm__("multu\t%2, %3"
++ : "=h" (usecs), "=l" (lo)
++ : "r" (usecs), "r" (lpj)
++ : GCC_REG_ACCUM);
++ else if (sizeof(long) == 8 && !R4000_WAR)
++ __asm__("dmultu\t%2, %3"
++ : "=h" (usecs), "=l" (lo)
++ : "r" (usecs), "r" (lpj)
++ : GCC_REG_ACCUM);
++ else if (sizeof(long) == 8 && R4000_WAR)
++ __asm__("dmultu\t%3, %4\n\tmfhi\t%0"
++ : "=r" (usecs), "=h" (hi), "=l" (lo)
++ : "r" (usecs), "r" (lpj)
++ : GCC_REG_ACCUM);
++
++ return usecs;
++}
++#else /* GCC_NO_H_CONSTRAINT, gcc >= 4.4 */
++static inline unsigned long __usecs_to_loops(unsigned long usecs,
++ unsigned long lpj)
++{
++ return ((uintx_t)usecs * lpj) >> BITS_PER_LONG;
++}
++#endif
+
+ /*
+ * Division by multiplication: you don't have to worry about
+@@ -62,8 +100,6 @@ static inline void __delay(unsigned long loops)
+
+ static inline void __udelay(unsigned long usecs, unsigned long lpj)
+ {
+- unsigned long hi, lo;
+-
+ /*
+ * The rates of 128 is rounded wrongly by the catchall case
+ * for 64-bit. Excessive precission? Probably ...
+@@ -77,23 +113,7 @@ static inline void __udelay(unsigned long usecs, unsigned long lpj)
+ 0x80000000ULL) >> 32);
+ #endif
+
+- if (sizeof(long) == 4)
+- __asm__("multu\t%2, %3"
+- : "=h" (usecs), "=l" (lo)
+- : "r" (usecs), "r" (lpj)
+- : GCC_REG_ACCUM);
+- else if (sizeof(long) == 8 && !R4000_WAR)
+- __asm__("dmultu\t%2, %3"
+- : "=h" (usecs), "=l" (lo)
+- : "r" (usecs), "r" (lpj)
+- : GCC_REG_ACCUM);
+- else if (sizeof(long) == 8 && R4000_WAR)
+- __asm__("dmultu\t%3, %4\n\tmfhi\t%0"
+- : "=r" (usecs), "=h" (hi), "=l" (lo)
+- : "r" (usecs), "r" (lpj)
+- : GCC_REG_ACCUM);
+-
+- __delay(usecs);
++ __delay(__usecs_to_loops(usecs, lpj));
+ }
+
+ #define __udelay_val cpu_data[raw_smp_processor_id()].udelay_val
+--
+1.6.0.4
+
+
+
projects / openwrt.git / commitdiff