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authorChris Metcalf <cmetcalf@tilera.com>2011-05-04 14:38:26 -0400
committerChris Metcalf <cmetcalf@tilera.com>2011-05-12 15:52:12 -0400
commit18aecc2b645bbb07851b196452a2af314222069b (patch)
tree959f765f69af01046c6e26db12b45c3390799d3e /arch/tile/kernel/futex_64.S
parentbe84cb43833ee40a42e08f5425d20310f16229c7 (diff)
arch/tile: finish enabling support for TILE-Gx 64-bit chip
This support was partially present in the existing code (look for "__tilegx__" ifdefs) but with this change you can build a working kernel using the TILE-Gx toolchain and ARCH=tilegx. Most of these files are new, generally adding a foo_64.c file where previously there was just a foo_32.c file. The ARCH=tilegx directive redirects to arch/tile, not arch/tilegx, using the existing SRCARCH mechanism in the top-level Makefile. Changes to existing files: - <asm/bitops.h> and <asm/bitops_32.h> changed to factor the include of <asm-generic/bitops/non-atomic.h> in the common header. - <asm/compat.h> and arch/tile/kernel/compat.c changed to remove the "const" markers I had put on compat_sys_execve() when trying to match some recent similar changes to the non-compat execve. It turns out the compat version wasn't "upgraded" to use const. - <asm/opcode-tile_64.h> and <asm/opcode_constants_64.h> were previously included accidentally, with the 32-bit contents. Now they have the proper 64-bit contents. Finally, I had to hack the existing hacky drivers/input/input-compat.h to add yet another "#ifdef" for INPUT_COMPAT_TEST (same as x86_64). Signed-off-by: Chris Metcalf <cmetcalf@tilera.com> Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> [drivers/input]
Diffstat (limited to 'arch/tile/kernel/futex_64.S')
-rw-r--r--arch/tile/kernel/futex_64.S55
1 files changed, 55 insertions, 0 deletions
diff --git a/arch/tile/kernel/futex_64.S b/arch/tile/kernel/futex_64.S
new file mode 100644
index 00000000000..f465d1eda20
--- /dev/null
+++ b/arch/tile/kernel/futex_64.S
@@ -0,0 +1,55 @@
+/*
+ * Copyright 2011 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.
+ *
+ * Atomically access user memory, but use MMU to avoid propagating
+ * kernel exceptions.
+ */
+
+#include <linux/linkage.h>
+#include <asm/errno.h>
+#include <asm/futex.h>
+#include <asm/page.h>
+#include <asm/processor.h>
+
+/*
+ * Provide a set of atomic memory operations supporting <asm/futex.h>.
+ *
+ * r0: user address to manipulate
+ * r1: new value to write, or for cmpxchg, old value to compare against
+ * r2: (cmpxchg only) new value to write
+ *
+ * Return __get_user struct, r0 with value, r1 with error.
+ */
+#define FUTEX_OP(name, ...) \
+STD_ENTRY(futex_##name) \
+ __VA_ARGS__; \
+ { \
+ move r1, zero; \
+ jrp lr \
+ }; \
+ STD_ENDPROC(futex_##name); \
+ .pushsection __ex_table,"a"; \
+ .quad 1b, get_user_fault; \
+ .popsection
+
+ .pushsection .fixup,"ax"
+get_user_fault:
+ { movei r1, -EFAULT; jrp lr }
+ ENDPROC(get_user_fault)
+ .popsection
+
+FUTEX_OP(cmpxchg, mtspr CMPEXCH_VALUE, r1; 1: cmpexch4 r0, r0, r2)
+FUTEX_OP(set, 1: exch4 r0, r0, r1)
+FUTEX_OP(add, 1: fetchadd4 r0, r0, r1)
+FUTEX_OP(or, 1: fetchor4 r0, r0, r1)
+FUTEX_OP(andn, nor r1, r1, zero; 1: fetchand4 r0, r0, r1)