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Diffstat (limited to 'arch/arm/mach-shmobile/setup-rcar-gen2.c')
-rw-r--r--arch/arm/mach-shmobile/setup-rcar-gen2.c91
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 000000000000..5734c24bf6c7
--- /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();
+}