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Diffstat (limited to 'arch/mips/vr41xx/common/bcu.c')
-rw-r--r--arch/mips/vr41xx/common/bcu.c222
1 files changed, 222 insertions, 0 deletions
diff --git a/arch/mips/vr41xx/common/bcu.c b/arch/mips/vr41xx/common/bcu.c
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index 00000000000..cdfa4273a1c
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+++ b/arch/mips/vr41xx/common/bcu.c
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+/*
+ * bcu.c, Bus Control Unit routines for the NEC VR4100 series.
+ *
+ * Copyright (C) 2002 MontaVista Software Inc.
+ * Author: Yoichi Yuasa <yyuasa@mvista.com, or source@mvista.com>
+ * Copyright (C) 2003-2005 Yoichi Yuasa <yuasa@hh.iij4u.or.jp>
+ *
+ * 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
+ */
+/*
+ * Changes:
+ * MontaVista Software Inc. <yyuasa@mvista.com> or <source@mvista.com>
+ * - New creation, NEC VR4122 and VR4131 are supported.
+ * - Added support for NEC VR4111 and VR4121.
+ *
+ * Yoichi Yuasa <yuasa@hh.iij4u.or.jp>
+ * - Added support for NEC VR4133.
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/smp.h>
+#include <linux/types.h>
+
+#include <asm/cpu.h>
+#include <asm/io.h>
+
+#define CLKSPEEDREG_TYPE1 (void __iomem *)KSEG1ADDR(0x0b000014)
+#define CLKSPEEDREG_TYPE2 (void __iomem *)KSEG1ADDR(0x0f000014)
+ #define CLKSP(x) ((x) & 0x001f)
+ #define CLKSP_VR4133(x) ((x) & 0x0007)
+
+ #define DIV2B 0x8000
+ #define DIV3B 0x4000
+ #define DIV4B 0x2000
+
+ #define DIVT(x) (((x) & 0xf000) >> 12)
+ #define DIVVT(x) (((x) & 0x0f00) >> 8)
+
+ #define TDIVMODE(x) (2 << (((x) & 0x1000) >> 12))
+ #define VTDIVMODE(x) (((x) & 0x0700) >> 8)
+
+static unsigned long vr41xx_vtclock;
+static unsigned long vr41xx_tclock;
+
+unsigned long vr41xx_get_vtclock_frequency(void)
+{
+ return vr41xx_vtclock;
+}
+
+EXPORT_SYMBOL_GPL(vr41xx_get_vtclock_frequency);
+
+unsigned long vr41xx_get_tclock_frequency(void)
+{
+ return vr41xx_tclock;
+}
+
+EXPORT_SYMBOL_GPL(vr41xx_get_tclock_frequency);
+
+static inline uint16_t read_clkspeed(void)
+{
+ switch (current_cpu_data.cputype) {
+ case CPU_VR4111:
+ case CPU_VR4121: return readw(CLKSPEEDREG_TYPE1);
+ case CPU_VR4122:
+ case CPU_VR4131:
+ case CPU_VR4133: return readw(CLKSPEEDREG_TYPE2);
+ default:
+ printk(KERN_INFO "Unexpected CPU of NEC VR4100 series\n");
+ break;
+ }
+
+ return 0;
+}
+
+static inline unsigned long calculate_pclock(uint16_t clkspeed)
+{
+ unsigned long pclock = 0;
+
+ switch (current_cpu_data.cputype) {
+ case CPU_VR4111:
+ case CPU_VR4121:
+ pclock = 18432000 * 64;
+ pclock /= CLKSP(clkspeed);
+ break;
+ case CPU_VR4122:
+ pclock = 18432000 * 98;
+ pclock /= CLKSP(clkspeed);
+ break;
+ case CPU_VR4131:
+ pclock = 18432000 * 108;
+ pclock /= CLKSP(clkspeed);
+ break;
+ case CPU_VR4133:
+ switch (CLKSP_VR4133(clkspeed)) {
+ case 0:
+ pclock = 133000000;
+ break;
+ case 1:
+ pclock = 149000000;
+ break;
+ case 2:
+ pclock = 165900000;
+ break;
+ case 3:
+ pclock = 199100000;
+ break;
+ case 4:
+ pclock = 265900000;
+ break;
+ default:
+ printk(KERN_INFO "Unknown PClock speed for NEC VR4133\n");
+ break;
+ }
+ break;
+ default:
+ printk(KERN_INFO "Unexpected CPU of NEC VR4100 series\n");
+ break;
+ }
+
+ printk(KERN_INFO "PClock: %ldHz\n", pclock);
+
+ return pclock;
+}
+
+static inline unsigned long calculate_vtclock(uint16_t clkspeed, unsigned long pclock)
+{
+ unsigned long vtclock = 0;
+
+ switch (current_cpu_data.cputype) {
+ case CPU_VR4111:
+ /* The NEC VR4111 doesn't have the VTClock. */
+ break;
+ case CPU_VR4121:
+ vtclock = pclock;
+ /* DIVVT == 9 Divide by 1.5 . VTClock = (PClock * 6) / 9 */
+ if (DIVVT(clkspeed) == 9)
+ vtclock = pclock * 6;
+ /* DIVVT == 10 Divide by 2.5 . VTClock = (PClock * 4) / 10 */
+ else if (DIVVT(clkspeed) == 10)
+ vtclock = pclock * 4;
+ vtclock /= DIVVT(clkspeed);
+ printk(KERN_INFO "VTClock: %ldHz\n", vtclock);
+ break;
+ case CPU_VR4122:
+ if(VTDIVMODE(clkspeed) == 7)
+ vtclock = pclock / 1;
+ else if(VTDIVMODE(clkspeed) == 1)
+ vtclock = pclock / 2;
+ else
+ vtclock = pclock / VTDIVMODE(clkspeed);
+ printk(KERN_INFO "VTClock: %ldHz\n", vtclock);
+ break;
+ case CPU_VR4131:
+ case CPU_VR4133:
+ vtclock = pclock / VTDIVMODE(clkspeed);
+ printk(KERN_INFO "VTClock: %ldHz\n", vtclock);
+ break;
+ default:
+ printk(KERN_INFO "Unexpected CPU of NEC VR4100 series\n");
+ break;
+ }
+
+ return vtclock;
+}
+
+static inline unsigned long calculate_tclock(uint16_t clkspeed, unsigned long pclock,
+ unsigned long vtclock)
+{
+ unsigned long tclock = 0;
+
+ switch (current_cpu_data.cputype) {
+ case CPU_VR4111:
+ if (!(clkspeed & DIV2B))
+ tclock = pclock / 2;
+ else if (!(clkspeed & DIV3B))
+ tclock = pclock / 3;
+ else if (!(clkspeed & DIV4B))
+ tclock = pclock / 4;
+ break;
+ case CPU_VR4121:
+ tclock = pclock / DIVT(clkspeed);
+ break;
+ case CPU_VR4122:
+ case CPU_VR4131:
+ case CPU_VR4133:
+ tclock = vtclock / TDIVMODE(clkspeed);
+ break;
+ default:
+ printk(KERN_INFO "Unexpected CPU of NEC VR4100 series\n");
+ break;
+ }
+
+ printk(KERN_INFO "TClock: %ldHz\n", tclock);
+
+ return tclock;
+}
+
+void vr41xx_calculate_clock_frequency(void)
+{
+ unsigned long pclock;
+ uint16_t clkspeed;
+
+ clkspeed = read_clkspeed();
+
+ pclock = calculate_pclock(clkspeed);
+ vr41xx_vtclock = calculate_vtclock(clkspeed, pclock);
+ vr41xx_tclock = calculate_tclock(clkspeed, pclock, vr41xx_vtclock);
+}
+
+EXPORT_SYMBOL_GPL(vr41xx_calculate_clock_frequency);