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]
diff --git a/arch/tile/lib/memset_64.c b/arch/tile/lib/memset_64.c
new file mode 100644
index 0000000..3873085
--- /dev/null
+++ b/arch/tile/lib/memset_64.c
@@ -0,0 +1,145 @@
+/*
+ * 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.
+ */
+
+#include <arch/chip.h>
+
+#include <linux/types.h>
+#include <linux/string.h>
+#include <linux/module.h>
+
+#undef memset
+
+void *memset(void *s, int c, size_t n)
+{
+ uint64_t *out64;
+ int n64, to_align64;
+ uint64_t v64;
+ uint8_t *out8 = s;
+
+ /* Experimentation shows that a trivial tight loop is a win up until
+ * around a size of 20, where writing a word at a time starts to win.
+ */
+#define BYTE_CUTOFF 20
+
+#if BYTE_CUTOFF < 7
+ /* This must be at least at least this big, or some code later
+ * on doesn't work.
+ */
+#error "BYTE_CUTOFF is too small"
+#endif
+
+ if (n < BYTE_CUTOFF) {
+ /* Strangely, this turns out to be the tightest way to
+ * write this loop.
+ */
+ if (n != 0) {
+ do {
+ /* Strangely, combining these into one line
+ * performs worse.
+ */
+ *out8 = c;
+ out8++;
+ } while (--n != 0);
+ }
+
+ return s;
+ }
+
+ /* Align 'out8'. We know n >= 7 so this won't write past the end. */
+ while (((uintptr_t) out8 & 7) != 0) {
+ *out8++ = c;
+ --n;
+ }
+
+ /* Align 'n'. */
+ while (n & 7)
+ out8[--n] = c;
+
+ out64 = (uint64_t *) out8;
+ n64 = n >> 3;
+
+ /* Tile input byte out to 64 bits. */
+ /* KLUDGE */
+ v64 = 0x0101010101010101ULL * (uint8_t)c;
+
+ /* This must be at least 8 or the following loop doesn't work. */
+#define CACHE_LINE_SIZE_IN_DOUBLEWORDS (CHIP_L2_LINE_SIZE() / 8)
+
+ /* Determine how many words we need to emit before the 'out32'
+ * pointer becomes aligned modulo the cache line size.
+ */
+ to_align64 = (-((uintptr_t)out64 >> 3)) &
+ (CACHE_LINE_SIZE_IN_DOUBLEWORDS - 1);
+
+ /* Only bother aligning and using wh64 if there is at least
+ * one full cache line to process. This check also prevents
+ * overrunning the end of the buffer with alignment words.
+ */
+ if (to_align64 <= n64 - CACHE_LINE_SIZE_IN_DOUBLEWORDS) {
+ int lines_left;
+
+ /* Align out64 mod the cache line size so we can use wh64. */
+ n64 -= to_align64;
+ for (; to_align64 != 0; to_align64--) {
+ *out64 = v64;
+ out64++;
+ }
+
+ /* Use unsigned divide to turn this into a right shift. */
+ lines_left = (unsigned)n64 / CACHE_LINE_SIZE_IN_DOUBLEWORDS;
+
+ do {
+ /* Only wh64 a few lines at a time, so we don't
+ * exceed the maximum number of victim lines.
+ */
+ int x = ((lines_left < CHIP_MAX_OUTSTANDING_VICTIMS())
+ ? lines_left
+ : CHIP_MAX_OUTSTANDING_VICTIMS());
+ uint64_t *wh = out64;
+ int i = x;
+ int j;
+
+ lines_left -= x;
+
+ do {
+ __insn_wh64(wh);
+ wh += CACHE_LINE_SIZE_IN_DOUBLEWORDS;
+ } while (--i);
+
+ for (j = x * (CACHE_LINE_SIZE_IN_DOUBLEWORDS / 4);
+ j != 0; j--) {
+ *out64++ = v64;
+ *out64++ = v64;
+ *out64++ = v64;
+ *out64++ = v64;
+ }
+ } while (lines_left != 0);
+
+ /* We processed all full lines above, so only this many
+ * words remain to be processed.
+ */
+ n64 &= CACHE_LINE_SIZE_IN_DOUBLEWORDS - 1;
+ }
+
+ /* Now handle any leftover values. */
+ if (n64 != 0) {
+ do {
+ *out64 = v64;
+ out64++;
+ } while (--n64 != 0);
+ }
+
+ return s;
+}
+EXPORT_SYMBOL(memset);