mirror of
git://projects.qi-hardware.com/openwrt-xburst.git
synced 2024-12-15 10:43:43 +02:00
5a76cd437c
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@18414 3c298f89-4303-0410-b956-a3cf2f4a3e73
156 lines
4.0 KiB
Diff
156 lines
4.0 KiB
Diff
MIPS: allow disabling the kernel FPU emulator
|
|
|
|
This patch allows turning off the in-kernel Algorithmics
|
|
FPU emulator support, which allows one to save a couple of
|
|
precious blocks on an embedded system.
|
|
|
|
Signed-off-by: Florian Fainelli <florian@openwrt.org>
|
|
--
|
|
--- a/arch/mips/Kconfig
|
|
+++ b/arch/mips/Kconfig
|
|
@@ -791,6 +791,17 @@ config I8259
|
|
config MIPS_BONITO64
|
|
bool
|
|
|
|
+config MIPS_FPU_EMU
|
|
+ bool "Enable FPU emulation"
|
|
+ default y
|
|
+ help
|
|
+ This option allows building a kernel with or without the Algorithmics
|
|
+ FPU emulator enabled. Turning off this option results in a kernel which
|
|
+ does not catch floating operations exceptions. Make sure that your toolchain
|
|
+ is configured to enable software floating point emulation in that case.
|
|
+
|
|
+ If unsure say Y here.
|
|
+
|
|
config MIPS_MSC
|
|
bool
|
|
|
|
--- a/arch/mips/math-emu/Makefile
|
|
+++ b/arch/mips/math-emu/Makefile
|
|
@@ -2,12 +2,14 @@
|
|
# Makefile for the Linux/MIPS kernel FPU emulation.
|
|
#
|
|
|
|
-obj-y := cp1emu.o ieee754m.o ieee754d.o ieee754dp.o ieee754sp.o ieee754.o \
|
|
+obj-y := kernel_linkage.o dsemul.o cp1emu.o
|
|
+
|
|
+obj-$(CONFIG_MIPS_FPU_EMU) += ieee754m.o ieee754d.o ieee754dp.o ieee754sp.o ieee754.o \
|
|
ieee754xcpt.o dp_frexp.o dp_modf.o dp_div.o dp_mul.o dp_sub.o \
|
|
dp_add.o dp_fsp.o dp_cmp.o dp_logb.o dp_scalb.o dp_simple.o \
|
|
dp_tint.o dp_fint.o dp_tlong.o dp_flong.o sp_frexp.o sp_modf.o \
|
|
sp_div.o sp_mul.o sp_sub.o sp_add.o sp_fdp.o sp_cmp.o sp_logb.o \
|
|
sp_scalb.o sp_simple.o sp_tint.o sp_fint.o sp_tlong.o sp_flong.o \
|
|
- dp_sqrt.o sp_sqrt.o kernel_linkage.o dsemul.o
|
|
+ dp_sqrt.o sp_sqrt.o
|
|
|
|
EXTRA_CFLAGS += -Werror
|
|
--- a/arch/mips/math-emu/cp1emu.c
|
|
+++ b/arch/mips/math-emu/cp1emu.c
|
|
@@ -56,6 +56,12 @@
|
|
#endif
|
|
#define __mips 4
|
|
|
|
+/* Further private data for which no space exists in mips_fpu_struct */
|
|
+
|
|
+struct mips_fpu_emulator_stats fpuemustats;
|
|
+
|
|
+#ifdef CONFIG_MIPS_FPU_EMU
|
|
+
|
|
/* Function which emulates a floating point instruction. */
|
|
|
|
static int fpu_emu(struct pt_regs *, struct mips_fpu_struct *,
|
|
@@ -66,10 +72,6 @@ static int fpux_emu(struct pt_regs *,
|
|
struct mips_fpu_struct *, mips_instruction);
|
|
#endif
|
|
|
|
-/* Further private data for which no space exists in mips_fpu_struct */
|
|
-
|
|
-struct mips_fpu_emulator_stats fpuemustats;
|
|
-
|
|
/* Control registers */
|
|
|
|
#define FPCREG_RID 0 /* $0 = revision id */
|
|
@@ -1273,6 +1275,13 @@ int fpu_emulator_cop1Handler(struct pt_r
|
|
|
|
return sig;
|
|
}
|
|
+#else
|
|
+int fpu_emulator_cop1Handler(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
|
|
+ int has_fpu)
|
|
+{
|
|
+ return 0;
|
|
+}
|
|
+#endif /* CONFIG_MIPS_FPU_EMU */
|
|
|
|
#ifdef CONFIG_DEBUG_FS
|
|
extern struct dentry *mips_debugfs_dir;
|
|
--- a/arch/mips/math-emu/dsemul.c
|
|
+++ b/arch/mips/math-emu/dsemul.c
|
|
@@ -109,6 +109,7 @@ int mips_dsemul(struct pt_regs *regs, mi
|
|
return SIGILL; /* force out of emulation loop */
|
|
}
|
|
|
|
+#ifdef CONFIG_MIPS_FPU_EMU
|
|
int do_dsemulret(struct pt_regs *xcp)
|
|
{
|
|
struct emuframe __user *fr;
|
|
@@ -165,3 +166,9 @@ int do_dsemulret(struct pt_regs *xcp)
|
|
|
|
return 1;
|
|
}
|
|
+#else
|
|
+int do_dsemulret(struct pt_regs *xcp)
|
|
+{
|
|
+ return 0;
|
|
+}
|
|
+#endif /* CONFIG_MIPS_FPU_EMU */
|
|
--- a/arch/mips/math-emu/kernel_linkage.c
|
|
+++ b/arch/mips/math-emu/kernel_linkage.c
|
|
@@ -29,6 +29,7 @@
|
|
|
|
#define SIGNALLING_NAN 0x7ff800007ff80000LL
|
|
|
|
+#ifdef CONFIG_MIPS_FPU_EMU
|
|
void fpu_emulator_init_fpu(void)
|
|
{
|
|
static int first = 1;
|
|
@@ -112,4 +113,36 @@ int fpu_emulator_restore_context32(struc
|
|
|
|
return err;
|
|
}
|
|
-#endif
|
|
+#endif /* CONFIG_64BIT */
|
|
+#else
|
|
+
|
|
+void fpu_emulator_init_fpu(void)
|
|
+{
|
|
+ printk(KERN_INFO "FPU emulator disabled, make sure your toolchain"
|
|
+ "was compiled with software floating point support (soft-float)\n");
|
|
+ return;
|
|
+}
|
|
+
|
|
+int fpu_emulator_save_context(struct sigcontext __user *sc)
|
|
+{
|
|
+ return 0;
|
|
+}
|
|
+
|
|
+int fpu_emulator_restore_context(struct sigcontext __user *sc)
|
|
+{
|
|
+ return 0;
|
|
+}
|
|
+
|
|
+int fpu_emulator_save_context32(struct sigcontext32 __user *sc)
|
|
+{
|
|
+ return 0;
|
|
+}
|
|
+
|
|
+int fpu_emulator_restore_context32(struct sigcontext32 __user *sc)
|
|
+{
|
|
+ return 0;
|
|
+}
|
|
+
|
|
+#ifdef CONFIG_64BIT
|
|
+#endif /* CONFIG_64BIT */
|
|
+#endif /* CONFIG_MIPS_FPU_EMU */
|