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, 223 insertions, 0 deletions

diff --git a/arch/tile/lib/usercopy_32.S b/arch/tile/lib/usercopy_32.S
new file mode 100644
index 000000000000..979f76d83746
--- /dev/null
+++ b/arch/tile/lib/usercopy_32.S
@@ -0,0 +1,223 @@
+/*
+ * 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.
+ */
+
+#include <linux/linkage.h>
+#include <asm/errno.h>
+#include <asm/cache.h>
+#include <arch/chip.h>
+
+/* Access user memory, but use MMU to avoid propagating kernel exceptions. */
+
+        .pushsection .fixup,"ax"
+
+get_user_fault:
+        { move r0, zero; move r1, zero }
+        { movei r2, -EFAULT; jrp lr }
+        ENDPROC(get_user_fault)
+
+put_user_fault:
+        { movei r0, -EFAULT; jrp lr }
+        ENDPROC(put_user_fault)
+
+        .popsection
+
+/*
+ * __get_user_N functions take a pointer in r0, and return 0 in r2
+ * on success, with the value in r0; or else -EFAULT in r2.
+ */
+#define __get_user_N(bytes, LOAD) \
+        STD_ENTRY(__get_user_##bytes); \
+1:      { LOAD r0, r0; move r1, zero; move r2, zero }; \
+        jrp lr; \
+        STD_ENDPROC(__get_user_##bytes); \
+        .pushsection __ex_table,"a"; \
+        .word 1b, get_user_fault; \
+        .popsection
+
+__get_user_N(1, lb_u)
+__get_user_N(2, lh_u)
+__get_user_N(4, lw)
+
+/*
+ * __get_user_8 takes a pointer in r0, and returns 0 in r2
+ * on success, with the value in r0/r1; or else -EFAULT in r2.
+ */
+        STD_ENTRY(__get_user_8);
+1:      { lw r0, r0; addi r1, r0, 4 };
+2:      { lw r1, r1; move r2, zero };
+        jrp lr;
+        STD_ENDPROC(__get_user_8);
+        .pushsection __ex_table,"a";
+        .word 1b, get_user_fault;
+        .word 2b, get_user_fault;
+        .popsection
+
+/*
+ * __put_user_N functions take a value in r0 and a pointer in r1,
+ * and return 0 in r0 on success or -EFAULT on failure.
+ */
+#define __put_user_N(bytes, STORE) \
+        STD_ENTRY(__put_user_##bytes); \
+1:      { STORE r1, r0; move r0, zero }; \
+        jrp lr; \
+        STD_ENDPROC(__put_user_##bytes); \
+        .pushsection __ex_table,"a"; \
+        .word 1b, put_user_fault; \
+        .popsection
+
+__put_user_N(1, sb)
+__put_user_N(2, sh)
+__put_user_N(4, sw)
+
+/*
+ * __put_user_8 takes a value in r0/r1 and a pointer in r2,
+ * and returns 0 in r0 on success or -EFAULT on failure.
+ */
+STD_ENTRY(__put_user_8)
+1:      { sw r2, r0; addi r2, r2, 4 }
+2:      { sw r2, r1; move r0, zero }
+        jrp lr
+        STD_ENDPROC(__put_user_8)
+        .pushsection __ex_table,"a"
+        .word 1b, put_user_fault
+        .word 2b, put_user_fault
+        .popsection
+
+
+/*
+ * strnlen_user_asm takes the pointer in r0, and the length bound in r1.
+ * It returns the length, including the terminating NUL, or zero on exception.
+ * If length is greater than the bound, returns one plus the bound.
+ */
+STD_ENTRY(strnlen_user_asm)
+        { bz r1, 2f; addi r3, r0, -1 }  /* bias down to include NUL */
+1:      { lb_u r4, r0; addi r1, r1, -1 }
+        bz r4, 2f
+        { bnzt r1, 1b; addi r0, r0, 1 }
+2:      { sub r0, r0, r3; jrp lr }
+        STD_ENDPROC(strnlen_user_asm)
+        .pushsection .fixup,"ax"
+strnlen_user_fault:
+        { move r0, zero; jrp lr }
+        ENDPROC(strnlen_user_fault)
+        .section __ex_table,"a"
+        .word 1b, strnlen_user_fault
+        .popsection
+
+/*
+ * strncpy_from_user_asm takes the kernel target pointer in r0,
+ * the userspace source pointer in r1, and the length bound (including
+ * the trailing NUL) in r2.  On success, it returns the string length
+ * (not including the trailing NUL), or -EFAULT on failure.
+ */
+STD_ENTRY(strncpy_from_user_asm)
+        { bz r2, 2f; move r3, r0 }
+1:      { lb_u r4, r1; addi r1, r1, 1; addi r2, r2, -1 }
+        { sb r0, r4; addi r0, r0, 1 }
+        bz r2, 2f
+        bnzt r4, 1b
+        addi r0, r0, -1   /* don't count the trailing NUL */
+2:      { sub r0, r0, r3; jrp lr }
+        STD_ENDPROC(strncpy_from_user_asm)
+        .pushsection .fixup,"ax"
+strncpy_from_user_fault:
+        { movei r0, -EFAULT; jrp lr }
+        ENDPROC(strncpy_from_user_fault)
+        .section __ex_table,"a"
+        .word 1b, strncpy_from_user_fault
+        .popsection
+
+/*
+ * clear_user_asm takes the user target address in r0 and the
+ * number of bytes to zero in r1.
+ * It returns the number of uncopiable bytes (hopefully zero) in r0.
+ * Note that we don't use a separate .fixup section here since we fall
+ * through into the "fixup" code as the last straight-line bundle anyway.
+ */
+STD_ENTRY(clear_user_asm)
+        { bz r1, 2f; or r2, r0, r1 }
+        andi r2, r2, 3
+        bzt r2, .Lclear_aligned_user_asm
+1:      { sb r0, zero; addi r0, r0, 1; addi r1, r1, -1 }
+        bnzt r1, 1b
+2:      { move r0, r1; jrp lr }
+        .pushsection __ex_table,"a"
+        .word 1b, 2b
+        .popsection
+
+.Lclear_aligned_user_asm:
+1:      { sw r0, zero; addi r0, r0, 4; addi r1, r1, -4 }
+        bnzt r1, 1b
+2:      { move r0, r1; jrp lr }
+        STD_ENDPROC(clear_user_asm)
+        .pushsection __ex_table,"a"
+        .word 1b, 2b
+        .popsection
+
+/*
+ * flush_user_asm takes the user target address in r0 and the
+ * number of bytes to flush in r1.
+ * It returns the number of unflushable bytes (hopefully zero) in r0.
+ */
+STD_ENTRY(flush_user_asm)
+        bz r1, 2f
+        { movei r2, L2_CACHE_BYTES; add r1, r0, r1 }
+        { sub r2, zero, r2; addi r1, r1, L2_CACHE_BYTES-1 }
+        { and r0, r0, r2; and r1, r1, r2 }
+        { sub r1, r1, r0 }
+1:      { flush r0; addi r1, r1, -CHIP_FLUSH_STRIDE() }
+        { addi r0, r0, CHIP_FLUSH_STRIDE(); bnzt r1, 1b }
+2:      { move r0, r1; jrp lr }
+        STD_ENDPROC(flush_user_asm)
+        .pushsection __ex_table,"a"
+        .word 1b, 2b
+        .popsection
+
+/*
+ * inv_user_asm takes the user target address in r0 and the
+ * number of bytes to invalidate in r1.
+ * It returns the number of not inv'able bytes (hopefully zero) in r0.
+ */
+STD_ENTRY(inv_user_asm)
+        bz r1, 2f
+        { movei r2, L2_CACHE_BYTES; add r1, r0, r1 }
+        { sub r2, zero, r2; addi r1, r1, L2_CACHE_BYTES-1 }
+        { and r0, r0, r2; and r1, r1, r2 }
+        { sub r1, r1, r0 }
+1:      { inv r0; addi r1, r1, -CHIP_INV_STRIDE() }
+        { addi r0, r0, CHIP_INV_STRIDE(); bnzt r1, 1b }
+2:      { move r0, r1; jrp lr }
+        STD_ENDPROC(inv_user_asm)
+        .pushsection __ex_table,"a"
+        .word 1b, 2b
+        .popsection
+
+/*
+ * finv_user_asm takes the user target address in r0 and the
+ * number of bytes to flush-invalidate in r1.
+ * It returns the number of not finv'able bytes (hopefully zero) in r0.
+ */
+STD_ENTRY(finv_user_asm)
+        bz r1, 2f
+        { movei r2, L2_CACHE_BYTES; add r1, r0, r1 }
+        { sub r2, zero, r2; addi r1, r1, L2_CACHE_BYTES-1 }
+        { and r0, r0, r2; and r1, r1, r2 }
+        { sub r1, r1, r0 }
+1:      { finv r0; addi r1, r1, -CHIP_FINV_STRIDE() }
+        { addi r0, r0, CHIP_FINV_STRIDE(); bnzt r1, 1b }
+2:      { move r0, r1; jrp lr }
+        STD_ENDPROC(finv_user_asm)
+        .pushsection __ex_table,"a"
+        .word 1b, 2b
+        .popsection