1 files changed, 91 insertions, 0 deletions
diff --git a/arch/arm/mach-shmobile/setup-rcar-gen2.c b/arch/arm/mach-shmobile/setup-rcar-gen2.c
new file mode 100644
index 00000000000..5734c24bf6c
--- /dev/null
+++ b/arch/arm/mach-shmobile/setup-rcar-gen2.c
@@ -0,0 +1,91 @@
+/*
+ * R-Car Generation 2 support
+ *
+ * Copyright (C) 2013  Renesas Solutions Corp.
+ * Copyright (C) 2013  Magnus Damm
+ *
+ * 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; version 2 of the License.
+ *
+ * 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., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include <linux/clocksource.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <mach/common.h>
+#include <mach/rcar-gen2.h>
+#include <asm/mach/arch.h>
+
+#define MODEMR 0xe6160060
+
+u32 __init rcar_gen2_read_mode_pins(void)
+{
+	void __iomem *modemr = ioremap_nocache(MODEMR, 4);
+	u32 mode;
+
+	BUG_ON(!modemr);
+	mode = ioread32(modemr);
+	iounmap(modemr);
+
+	return mode;
+}
+
+#define CNTCR 0
+#define CNTFID0 0x20
+
+void __init rcar_gen2_timer_init(void)
+{
+#ifdef CONFIG_ARM_ARCH_TIMER
+	u32 mode = rcar_gen2_read_mode_pins();
+	void __iomem *base;
+	int extal_mhz = 0;
+	u32 freq;
+
+	/* At Linux boot time the r8a7790 arch timer comes up
+	 * with the counter disabled. Moreover, it may also report
+	 * a potentially incorrect fixed 13 MHz frequency. To be
+	 * correct these registers need to be updated to use the
+	 * frequency EXTAL / 2 which can be determined by the MD pins.
+	 */
+
+	switch (mode & (MD(14) | MD(13))) {
+	case 0:
+		extal_mhz = 15;
+		break;
+	case MD(13):
+		extal_mhz = 20;
+		break;
+	case MD(14):
+		extal_mhz = 26;
+		break;
+	case MD(13) | MD(14):
+		extal_mhz = 30;
+		break;
+	}
+
+	/* The arch timer frequency equals EXTAL / 2 */
+	freq = extal_mhz * (1000000 / 2);
+
+	/* Remap "armgcnt address map" space */
+	base = ioremap(0xe6080000, PAGE_SIZE);
+
+	/* Update registers with correct frequency */
+	iowrite32(freq, base + CNTFID0);
+	asm volatile("mcr p15, 0, %0, c14, c0, 0" : : "r" (freq));
+
+	/* make sure arch timer is started by setting bit 0 of CNTCR */
+	iowrite32(1, base + CNTCR);
+	iounmap(base);
+#endif /* CONFIG_ARM_ARCH_TIMER */
+
+	clocksource_of_init();
+}