---

yaml --- r: 144922 b: refs/heads/master c: b070a03 h: refs/heads/master v: v3
git-mirror · May 12, 2009 · ff539b4 · ff539b4
1 parent 31ea24b
commit ff539b4
Show file tree

Hide file tree

Showing 4 changed files with 30 additions and 1 deletion.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: d15f05eb8cc4ad59699c16b8ae834b85c6d39bfe
+refs/heads/master: b070a03f6490b0ac8d95c51b55a64e433d9160ab
diff --git a/trunk/arch/xtensa/Kconfig b/trunk/arch/xtensa/Kconfig
@@ -80,6 +80,7 @@ config XTENSA_VARIANT_S6000
 	bool "s6000 - Stretch software configurable processor"
 	select VARIANT_IRQ_SWITCH
 	select ARCH_REQUIRE_GPIOLIB
+	select XTENSA_CALIBRATE_CCOUNT
 endchoice
 
 config XTENSA_UNALIGNED_USER

diff --git a/trunk/arch/xtensa/variants/s6000/Makefile b/trunk/arch/xtensa/variants/s6000/Makefile
@@ -1,3 +1,4 @@
 # s6000 Makefile
 
 obj-y		+= irq.o gpio.o
+obj-$(CONFIG_XTENSA_CALIBRATE_CCOUNT)	+= delay.o
diff --git a/trunk/arch/xtensa/variants/s6000/delay.c b/trunk/arch/xtensa/variants/s6000/delay.c
@@ -0,0 +1,27 @@
+#include <asm/delay.h>
+#include <asm/timex.h>
+#include <asm/io.h>
+#include <variant/hardware.h>
+
+#define LOOPS 10
+void platform_calibrate_ccount(void)
+{
+	u32 uninitialized_var(a);
+	u32 uninitialized_var(u);
+	u32 b;
+	u32 tstamp = S6_REG_GREG1 + S6_GREG1_GLOBAL_TIMER;
+	int i = LOOPS+1;
+	do {
+		u32 t = u;
+		asm volatile(
+		"1:	l32i %0, %2, 0 ;"
+		"	beq %0, %1, 1b ;"
+		: "=&a"(u) : "a"(t), "a"(tstamp));
+		b = xtensa_get_ccount();
+		if (i == LOOPS)
+			a = b;
+	} while (--i >= 0);
+	b -= a;
+	nsec_per_ccount = (LOOPS * 10000) / b;
+	ccount_per_jiffy = b * (100000UL / (LOOPS * HZ));
+}