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authorLinus Torvalds <torvalds@linux-foundation.org>2011-03-17 20:11:25 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2011-03-17 20:11:25 +0300
commit7b7adc4a016a1decb806eb71ecab98721fa7f146 (patch)
tree0a6f9a6e5659faa94604fbc575382a18f143c657 /arch/unicore32/lib/delay.S
parent31598e8713ef501c8f6aad2e2ec8a9457e8877c1 (diff)
parent289d6b0e287e0acd85f3e6b7ea6c2cb5c234909a (diff)
downloadlinux-7b7adc4a016a1decb806eb71ecab98721fa7f146.tar.xz
Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/epip/linux-2.6-unicore32
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/epip/linux-2.6-unicore32: (40 commits) unicore32: rewrite arch-specific tlb.h to use asm-generic version unicore32: modify io_p2v and io_v2p macros, and adjust PKUNITY_mmio_BASEs unicore32: replace unicore32-specific iomap functions with generic lib implementation unicore32 machine related: add frame buffer driver for pkunity-v3 soc unicore32 machine related files: add i2c bus drivers for pkunity-v3 soc unicore32 io: redefine __REG(x) and re-use readl/writel funcs unicore32 i8042 upgrade and bugfix: adjust resource request region type unicore32 upgrade to v2.6.38-rc5: add one more paramter for pte_alloc_map call unicore32 i8042: adjust io funcs of i8042-unicore32io.h unicore32: rename PKUNITY_IOSPACE_BASE to PKUNITY_MMIO_BASE unicore32: modify function names and parameters for irq_chips unicore32: remove unused lines in arch/unicore32/include/asm/irq.h unicore32 time.c: change calculate method for clock_event_device unicore32: ADD MAINTAINER for unicore32 architecture unicore32 machine related files: ps2 driver unicore32 machine related files: pci bus handling unicore32 machine related files: hardware registers unicore32 machine related files: core files unicore32 additional architecture files: boot process unicore32 additional architecture files: low-level lib: misc ... Acked-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'arch/unicore32/lib/delay.S')
-rw-r--r--arch/unicore32/lib/delay.S51
1 files changed, 51 insertions, 0 deletions
diff --git a/arch/unicore32/lib/delay.S b/arch/unicore32/lib/delay.S
new file mode 100644
index 000000000000..24664c009e78
--- /dev/null
+++ b/arch/unicore32/lib/delay.S
@@ -0,0 +1,51 @@
+/*
+ * linux/arch/unicore32/lib/delay.S
+ *
+ * Code specific to PKUnity SoC and UniCore ISA
+ *
+ * Copyright (C) 2001-2010 GUAN Xue-tao
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <asm/param.h>
+ .text
+
+.LC0: .word loops_per_jiffy
+.LC1: .word (2199023*HZ)>>11
+
+/*
+ * r0 <= 2000
+ * lpj <= 0x01ffffff (max. 3355 bogomips)
+ * HZ <= 1000
+ */
+
+ENTRY(__udelay)
+ ldw r2, .LC1
+ mul r0, r2, r0
+ENTRY(__const_udelay) @ 0 <= r0 <= 0x7fffff06
+ ldw r2, .LC0
+ ldw r2, [r2] @ max = 0x01ffffff
+ mov r0, r0 >> #14 @ max = 0x0001ffff
+ mov r2, r2 >> #10 @ max = 0x00007fff
+ mul r0, r2, r0 @ max = 2^32-1
+ mov.a r0, r0 >> #6
+ cmoveq pc, lr
+
+/*
+ * loops = r0 * HZ * loops_per_jiffy / 1000000
+ *
+ * Oh, if only we had a cycle counter...
+ */
+
+@ Delay routine
+ENTRY(__delay)
+ sub.a r0, r0, #2
+ bua __delay
+ mov pc, lr
+ENDPROC(__udelay)
+ENDPROC(__const_udelay)
+ENDPROC(__delay)