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Diffstat (limited to 'arch/mips/cpu/mips32/incaip/incaip_clock.c')
-rw-r--r--arch/mips/cpu/mips32/incaip/incaip_clock.c116
1 files changed, 116 insertions, 0 deletions
diff --git a/arch/mips/cpu/mips32/incaip/incaip_clock.c b/arch/mips/cpu/mips32/incaip/incaip_clock.c
new file mode 100644
index 000000000..b65dfe0e1
--- /dev/null
+++ b/arch/mips/cpu/mips32/incaip/incaip_clock.c
@@ -0,0 +1,116 @@
+/*
+ * (C) Copyright 2003
+ * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+ *
+ * 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
+ */
+
+#include <common.h>
+#include <asm/inca-ip.h>
+
+
+/*******************************************************************************
+*
+* get_cpuclk - returns the frequency of the CPU.
+*
+* Gets the value directly from the INCA-IP hardware.
+*
+* RETURNS:
+* 150.000.000 for 150 MHz
+* 133.333.333 for 133 MHz (= 400MHz/3)
+* 100.000.000 for 100 MHz (= 400MHz/4)
+* NOTE:
+* This functions should be used by the hardware driver to get the correct
+* frequency of the CPU. Don't use the macros, which are set to init the CPU
+* frequency in the ROM code.
+*/
+uint incaip_get_cpuclk (void)
+{
+ /*-------------------------------------------------------------------------*/
+ /* CPU Clock Input Multiplexer (MUX I) */
+ /* Multiplexer MUX I selects the maximum input clock to the CPU. */
+ /*-------------------------------------------------------------------------*/
+ if (*((volatile ulong *) INCA_IP_CGU_CGU_MUXCR) &
+ INCA_IP_CGU_CGU_MUXCR_MUXI) {
+ /* MUX I set to 150 MHz clock */
+ return 150000000;
+ } else {
+ /* MUX I set to 100/133 MHz clock */
+ if (*((volatile ulong *) INCA_IP_CGU_CGU_DIVCR) & 0x40) {
+ /* Division value is 1/3, maximum CPU operating */
+ /* frequency is 133.3 MHz */
+ return 133333333;
+ } else {
+ /* Division value is 1/4, maximum CPU operating */
+ /* frequency is 100 MHz */
+ return 100000000;
+ }
+ }
+}
+
+/*******************************************************************************
+*
+* get_fpiclk - returns the frequency of the FPI bus.
+*
+* Gets the value directly from the INCA-IP hardware.
+*
+* RETURNS: Frquency in Hz
+*
+* NOTE:
+* This functions should be used by the hardware driver to get the correct
+* frequency of the CPU. Don't use the macros, which are set to init the CPU
+* frequency in the ROM code.
+* The calculation for the
+*/
+uint incaip_get_fpiclk (void)
+{
+ uint clkCPU;
+
+ clkCPU = incaip_get_cpuclk ();
+
+ switch (*((volatile ulong *) INCA_IP_CGU_CGU_DIVCR) & 0xC) {
+ case 0x4:
+ return clkCPU >> 1; /* devided by 2 */
+ break;
+ case 0x8:
+ return clkCPU >> 2; /* devided by 4 */
+ break;
+ default:
+ return clkCPU;
+ break;
+ }
+}
+
+int incaip_set_cpuclk (void)
+{
+ extern void ebu_init(long);
+ extern void cgu_init(long);
+ extern void sdram_init(long);
+ char tmp[64];
+ ulong cpuclk;
+
+ if (getenv_f("cpuclk", tmp, sizeof (tmp)) > 0) {
+ cpuclk = simple_strtoul (tmp, NULL, 10) * 1000000;
+ cgu_init (cpuclk);
+ ebu_init (cpuclk);
+ sdram_init (cpuclk);
+ }
+
+ return 0;
+}