Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 221 insertions, 0 deletions

diff --git a/arch/mips/kernel/r4k_switch.S b/arch/mips/kernel/r4k_switch.S
new file mode 100644
index 000000000000..1fc3b2eb12bd
--- /dev/null
+++ b/arch/mips/kernel/r4k_switch.S
@@ -0,0 +1,221 @@
+/*
+ * 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
+ * for more details.
+ *
+ * Copyright (C) 1994, 1995, 1996, 1998, 1999, 2002, 2003 Ralf Baechle
+ * Copyright (C) 1996 David S. Miller (dm@engr.sgi.com)
+ * Copyright (C) 1994, 1995, 1996, by Andreas Busse
+ * Copyright (C) 1999 Silicon Graphics, Inc.
+ * Copyright (C) 2000 MIPS Technologies, Inc.
+ *    written by Carsten Langgaard, carstenl@mips.com
+ */
+#include <linux/config.h>
+#include <asm/asm.h>
+#include <asm/cachectl.h>
+#include <asm/fpregdef.h>
+#include <asm/mipsregs.h>
+#include <asm/offset.h>
+#include <asm/page.h>
+#include <asm/pgtable-bits.h>
+#include <asm/regdef.h>
+#include <asm/stackframe.h>
+#include <asm/thread_info.h>
+
+#include <asm/asmmacro.h>
+
+/*
+ * Offset to the current process status flags, the first 32 bytes of the
+ * stack are not used.
+ */
+#define ST_OFF (_THREAD_SIZE - 32 - PT_SIZE + PT_STATUS)
+
+/*
+ * FPU context is saved iff the process has used it's FPU in the current
+ * time slice as indicated by _TIF_USEDFPU.  In any case, the CU1 bit for user
+ * space STATUS register should be 0, so that a process *always* starts its 
+ * userland with FPU disabled after each context switch.
+ *
+ * FPU will be enabled as soon as the process accesses FPU again, through
+ * do_cpu() trap.
+ */
+
+/*
+ * task_struct *resume(task_struct *prev, task_struct *next,
+ *                     struct thread_info *next_ti)
+ */
+	.align	5
+	LEAF(resume)
+#ifndef CONFIG_CPU_HAS_LLSC
+	sw	zero, ll_bit
+#endif
+	mfc0	t1, CP0_STATUS
+	LONG_S	t1, THREAD_STATUS(a0)
+	cpu_save_nonscratch a0
+	LONG_S	ra, THREAD_REG31(a0)
+
+	/*
+	 * check if we need to save FPU registers
+	 */
+	PTR_L	t3, TASK_THREAD_INFO(a0)
+	LONG_L	t0, TI_FLAGS(t3)
+	li	t1, _TIF_USEDFPU
+	and	t2, t0, t1
+	beqz	t2, 1f
+	nor	t1, zero, t1
+
+	and	t0, t0, t1
+	LONG_S	t0, TI_FLAGS(t3)
+
+	/*
+	 * clear saved user stack CU1 bit
+	 */
+	LONG_L	t0, ST_OFF(t3)
+	li	t1, ~ST0_CU1
+	and	t0, t0, t1
+	LONG_S	t0, ST_OFF(t3)
+
+	fpu_save_double a0 t1 t0 t2		# c0_status passed in t1
+						# clobbers t0 and t2
+1:
+
+	/*
+	 * The order of restoring the registers takes care of the race
+	 * updating $28, $29 and kernelsp without disabling ints.
+	 */
+	move	$28, a2
+	cpu_restore_nonscratch a1
+
+	PTR_ADDIU	t0, $28, _THREAD_SIZE - 32
+	set_saved_sp	t0, t1, t2
+
+	mfc0	t1, CP0_STATUS		/* Do we really need this? */
+	li	a3, 0xff01
+	and	t1, a3
+	LONG_L	a2, THREAD_STATUS(a1)
+	nor	a3, $0, a3
+	and	a2, a3
+	or	a2, t1
+	mtc0	a2, CP0_STATUS
+	move	v0, a0
+	jr	ra
+	END(resume)
+
+/*
+ * Save a thread's fp context.
+ */
+LEAF(_save_fp)
+#ifdef CONFIG_MIPS64
+	mfc0	t1, CP0_STATUS
+#endif
+	fpu_save_double a0 t1 t0 t2		# clobbers t1
+	jr	ra
+	END(_save_fp)
+
+/*
+ * Restore a thread's fp context.
+ */
+LEAF(_restore_fp)
+	fpu_restore_double a0, t1		# clobbers t1
+	jr	ra
+	END(_restore_fp)
+
+/*
+ * Load the FPU with signalling NANS.  This bit pattern we're using has
+ * the property that no matter whether considered as single or as double
+ * precision represents signaling NANS.
+ *
+ * We initialize fcr31 to rounding to nearest, no exceptions.
+ */
+
+#define FPU_DEFAULT  0x00000000
+
+LEAF(_init_fpu)
+	mfc0	t0, CP0_STATUS
+	li	t1, ST0_CU1
+	or	t0, t1
+	mtc0	t0, CP0_STATUS
+	fpu_enable_hazard
+
+	li	t1, FPU_DEFAULT
+	ctc1	t1, fcr31
+
+	li	t1, -1				# SNaN
+
+#ifdef CONFIG_MIPS64
+	sll	t0, t0, 5
+	bgez	t0, 1f				# 16 / 32 register mode?
+
+	dmtc1	t1, $f1
+	dmtc1	t1, $f3
+	dmtc1	t1, $f5
+	dmtc1	t1, $f7
+	dmtc1	t1, $f9
+	dmtc1	t1, $f11
+	dmtc1	t1, $f13
+	dmtc1	t1, $f15
+	dmtc1	t1, $f17
+	dmtc1	t1, $f19
+	dmtc1	t1, $f21
+	dmtc1	t1, $f23
+	dmtc1	t1, $f25
+	dmtc1	t1, $f27
+	dmtc1	t1, $f29
+	dmtc1	t1, $f31
+1:
+#endif
+	
+#ifdef CONFIG_CPU_MIPS32
+	mtc1	t1, $f0
+	mtc1	t1, $f1
+	mtc1	t1, $f2
+	mtc1	t1, $f3
+	mtc1	t1, $f4
+	mtc1	t1, $f5
+	mtc1	t1, $f6
+	mtc1	t1, $f7
+	mtc1	t1, $f8
+	mtc1	t1, $f9
+	mtc1	t1, $f10
+	mtc1	t1, $f11
+	mtc1	t1, $f12
+	mtc1	t1, $f13
+	mtc1	t1, $f14
+	mtc1	t1, $f15
+	mtc1	t1, $f16
+	mtc1	t1, $f17
+	mtc1	t1, $f18
+	mtc1	t1, $f19
+	mtc1	t1, $f20
+	mtc1	t1, $f21
+	mtc1	t1, $f22
+	mtc1	t1, $f23
+	mtc1	t1, $f24
+	mtc1	t1, $f25
+	mtc1	t1, $f26
+	mtc1	t1, $f27
+	mtc1	t1, $f28
+	mtc1	t1, $f29
+	mtc1	t1, $f30
+	mtc1	t1, $f31
+#else
+	.set	mips3
+	dmtc1	t1, $f0
+	dmtc1	t1, $f2
+	dmtc1	t1, $f4
+	dmtc1	t1, $f6
+	dmtc1	t1, $f8
+	dmtc1	t1, $f10
+	dmtc1	t1, $f12
+	dmtc1	t1, $f14
+	dmtc1	t1, $f16
+	dmtc1	t1, $f18
+	dmtc1	t1, $f20
+	dmtc1	t1, $f22
+	dmtc1	t1, $f24
+	dmtc1	t1, $f26
+	dmtc1	t1, $f28
+	dmtc1	t1, $f30
+#endif
+	jr	ra
+	END(_init_fpu)