arch/tile: core support for Tilera 32-bit chips.

This change is the core kernel support for TILEPro and TILE64 chips.
No driver support (except the console driver) is included yet.

This includes the relevant Linux headers in asm/; the low-level
low-level "Tile architecture" headers in arch/, which are
shared with the hypervisor, etc., and are build-system agnostic;
and the relevant hypervisor headers in hv/.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Reviewed-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 165 insertions, 0 deletions

diff --git a/arch/tile/include/asm/thread_info.h b/arch/tile/include/asm/thread_info.h
new file mode 100644
index 000000000000..9024bf3530aa
--- /dev/null
+++ b/arch/tile/include/asm/thread_info.h
@@ -0,0 +1,165 @@
+/*
+ * Copyright (C) 2002  David Howells (dhowells@redhat.com)
+ * Copyright 2010 Tilera Corporation. All Rights Reserved.
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful, but
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ *   NON INFRINGEMENT.  See the GNU General Public License for
+ *   more details.
+ */
+
+#ifndef _ASM_TILE_THREAD_INFO_H
+#define _ASM_TILE_THREAD_INFO_H
+
+#include <asm/processor.h>
+#include <asm/page.h>
+#ifndef __ASSEMBLY__
+
+/*
+ * Low level task data that assembly code needs immediate access to.
+ * The structure is placed at the bottom of the supervisor stack.
+ */
+struct thread_info {
+	struct task_struct	*task;		/* main task structure */
+	struct exec_domain	*exec_domain;	/* execution domain */
+	unsigned long		flags;		/* low level flags */
+	unsigned long		status;		/* thread-synchronous flags */
+	__u32			homecache_cpu;	/* CPU we are homecached on */
+	__u32			cpu;		/* current CPU */
+	int			preempt_count;	/* 0 => preemptable,
+						   <0 => BUG */
+
+	mm_segment_t		addr_limit;	/* thread address space
+						   (KERNEL_DS or USER_DS) */
+	struct restart_block	restart_block;
+	struct single_step_state *step_state;	/* single step state
+						   (if non-zero) */
+};
+
+/*
+ * macros/functions for gaining access to the thread information structure.
+ */
+#define INIT_THREAD_INFO(tsk)			\
+{						\
+	.task		= &tsk,			\
+	.exec_domain	= &default_exec_domain,	\
+	.flags		= 0,			\
+	.cpu		= 0,			\
+	.preempt_count	= INIT_PREEMPT_COUNT,	\
+	.addr_limit	= KERNEL_DS,		\
+	.restart_block	= {			\
+		.fn = do_no_restart_syscall,	\
+	},					\
+	.step_state	= 0,			\
+}
+
+#define init_thread_info	(init_thread_union.thread_info)
+#define init_stack		(init_thread_union.stack)
+
+#endif /* !__ASSEMBLY__ */
+
+#if PAGE_SIZE < 8192
+#define THREAD_SIZE_ORDER (13 - PAGE_SHIFT)
+#else
+#define THREAD_SIZE_ORDER (0)
+#endif
+
+#define THREAD_SIZE (PAGE_SIZE << THREAD_SIZE_ORDER)
+#define LOG2_THREAD_SIZE (PAGE_SHIFT + THREAD_SIZE_ORDER)
+
+#define STACK_WARN             (THREAD_SIZE/8)
+
+#ifndef __ASSEMBLY__
+
+/* How to get the thread information struct from C. */
+register unsigned long stack_pointer __asm__("sp");
+
+#define current_thread_info() \
+  ((struct thread_info *)(stack_pointer & -THREAD_SIZE))
+
+#define __HAVE_ARCH_THREAD_INFO_ALLOCATOR
+extern struct thread_info *alloc_thread_info(struct task_struct *task);
+extern void free_thread_info(struct thread_info *info);
+
+/* Switch boot idle thread to a freshly-allocated stack and free old stack. */
+extern void cpu_idle_on_new_stack(struct thread_info *old_ti,
+				  unsigned long new_sp,
+				  unsigned long new_ss10);
+
+#else /* __ASSEMBLY__ */
+
+/* how to get the thread information struct from ASM */
+#ifdef __tilegx__
+#define GET_THREAD_INFO(reg) move reg, sp; mm reg, zero, LOG2_THREAD_SIZE, 63
+#else
+#define GET_THREAD_INFO(reg) mm reg, sp, zero, LOG2_THREAD_SIZE, 31
+#endif
+
+#endif /* !__ASSEMBLY__ */
+
+#define PREEMPT_ACTIVE		0x10000000
+
+/*
+ * Thread information flags that various assembly files may need to access.
+ * Keep flags accessed frequently in low bits, particular since it makes
+ * it easier to build constants in assembly.
+ */
+#define TIF_SIGPENDING		0	/* signal pending */
+#define TIF_NEED_RESCHED	1	/* rescheduling necessary */
+#define TIF_SINGLESTEP		2	/* restore singlestep on return to
+					   user mode */
+#define TIF_ASYNC_TLB		3	/* got an async TLB fault in kernel */
+#define TIF_SYSCALL_TRACE	4	/* syscall trace active */
+#define TIF_SYSCALL_AUDIT	5	/* syscall auditing active */
+#define TIF_SECCOMP		6	/* secure computing */
+#define TIF_MEMDIE		7	/* OOM killer at work */
+
+#define _TIF_SIGPENDING		(1<<TIF_SIGPENDING)
+#define _TIF_NEED_RESCHED	(1<<TIF_NEED_RESCHED)
+#define _TIF_SINGLESTEP		(1<<TIF_SINGLESTEP)
+#define _TIF_ASYNC_TLB		(1<<TIF_ASYNC_TLB)
+#define _TIF_SYSCALL_TRACE	(1<<TIF_SYSCALL_TRACE)
+#define _TIF_SYSCALL_AUDIT	(1<<TIF_SYSCALL_AUDIT)
+#define _TIF_SECCOMP		(1<<TIF_SECCOMP)
+#define _TIF_MEMDIE		(1<<TIF_MEMDIE)
+
+/* Work to do on any return to user space. */
+#define _TIF_ALLWORK_MASK \
+  (_TIF_SIGPENDING|_TIF_NEED_RESCHED|_TIF_SINGLESTEP|_TIF_ASYNC_TLB)
+
+/*
+ * Thread-synchronous status.
+ *
+ * This is different from the flags in that nobody else
+ * ever touches our thread-synchronous status, so we don't
+ * have to worry about atomic accesses.
+ */
+#ifdef __tilegx__
+#define TS_COMPAT		0x0001	/* 32-bit compatibility mode */
+#endif
+#define TS_POLLING		0x0004	/* in idle loop but not sleeping */
+#define TS_RESTORE_SIGMASK	0x0008	/* restore signal mask in do_signal */
+#define TS_EXEC_HASH_SET	0x0010	/* apply TS_EXEC_HASH_xxx flags */
+#define TS_EXEC_HASH_RO		0x0020	/* during exec, hash r/o segments */
+#define TS_EXEC_HASH_RW		0x0040	/* during exec, hash r/w segments */
+#define TS_EXEC_HASH_STACK	0x0080	/* during exec, hash the stack */
+#define TS_EXEC_HASH_FLAGS	0x00f0	/* mask for TS_EXEC_HASH_xxx flags */
+
+#define tsk_is_polling(t) (task_thread_info(t)->status & TS_POLLING)
+
+#ifndef __ASSEMBLY__
+#define HAVE_SET_RESTORE_SIGMASK	1
+static inline void set_restore_sigmask(void)
+{
+	struct thread_info *ti = current_thread_info();
+	ti->status |= TS_RESTORE_SIGMASK;
+	set_bit(TIF_SIGPENDING, &ti->flags);
+}
+#endif	/* !__ASSEMBLY__ */
+
+#endif /* _ASM_TILE_THREAD_INFO_H */