1 files changed, 96 insertions, 0 deletions
diff --git a/cpu/arm920t/speed.c b/cpu/arm920t/speed.c
new file mode 100644
index 0000000..1ee0c1a
--- /dev/null
+++ b/cpu/arm920t/speed.c
@@ -0,0 +1,96 @@
+/*
+ * (C) Copyright 2001-2002
+ * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+ *
+ * (C) Copyright 2002
+ * David Mueller, ELSOFT AG, d.mueller@elsoft.ch
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * 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.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+/* This code should work for both the S3C2400 and the S3C2410
+ * as they seem to have the same PLL and clock machinery inside.
+ * The different address mapping is handled by the s3c24xx.h files below.
+ */
+
+#include <common.h>
+#if defined(CONFIG_S3C2400)
+#include <s3c2400.h>
+#elif defined(CONFIG_S3C2410)
+#include <s3c2410.h>
+#endif
+
+#define MPLL 0
+#define UPLL 1
+
+/* ------------------------------------------------------------------------- */
+/* NOTE: This describes the proper use of this file.
+ *
+ * CONFIG_PLL_INPUT_FREQ should be defined as the input frequency of the PLL.
+ *
+ * get_FCLK(), get_HCLK(), get_PCLK() and get_UCLK() return the clock of
+ * the specified bus in HZ.
+ */
+/* ------------------------------------------------------------------------- */
+
+static ulong get_PLLCLK(int pllreg)
+{
+    ulong r, m, p, s;
+
+    if (pllreg == MPLL)
+	r = rMPLLCON;
+    else if (pllreg == UPLL)
+	r = rUPLLCON;
+    else
+	hang();
+
+    m = ((r & 0xFF000) >> 12) + 8;
+    p = ((r & 0x003F0) >> 4) + 2;
+    s = r & 0x3;
+
+    return((CONFIG_PLL_INPUT_FREQ * m) / (p << s));
+}
+
+/* return FCLK frequency */
+ulong get_FCLK(void)
+{
+    return(get_PLLCLK(MPLL));
+}
+
+/* return HCLK frequency */
+ulong get_HCLK(void)
+{
+    ulong clkdiv = rCLKDIVN;
+
+    return((clkdiv & 0x2) ? get_FCLK()/2 : get_FCLK());
+}
+
+/* return PCLK frequency */
+ulong get_PCLK(void)
+{
+    ulong clkdiv = rCLKDIVN;
+
+    return((clkdiv & 0x1) ? get_HCLK()/2 : get_HCLK());
+}
+
+/* return UCLK frequency */
+ulong get_UCLK(void)
+{
+    return(get_PLLCLK(UPLL));
+}