Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 98 insertions, 0 deletions

diff --git a/arch/arm/mach-omap2/omap_hwmod_reset.c b/arch/arm/mach-omap2/omap_hwmod_reset.c
new file mode 100644
index 000000000..143623bb0
--- /dev/null
+++ b/arch/arm/mach-omap2/omap_hwmod_reset.c
@@ -0,0 +1,98 @@
+/*
+ * OMAP IP block custom reset and preprogramming stubs
+ *
+ * Copyright (C) 2012 Texas Instruments, Inc.
+ * Paul Walmsley
+ *
+ * A small number of IP blocks need custom reset and preprogramming
+ * functions.  The stubs in this file provide a standard way for the
+ * hwmod code to call these functions, which are to be located under
+ * drivers/.
+ *
+ * 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.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; 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/kernel.h>
+#include <linux/errno.h>
+
+#include "omap_hwmod.h"
+#include "common.h"
+
+#define OMAP_RTC_STATUS_REG	0x44
+#define OMAP_RTC_KICK0_REG	0x6c
+#define OMAP_RTC_KICK1_REG	0x70
+
+#define OMAP_RTC_KICK0_VALUE	0x83E70B13
+#define OMAP_RTC_KICK1_VALUE	0x95A4F1E0
+#define OMAP_RTC_STATUS_BUSY	BIT(0)
+#define OMAP_RTC_MAX_READY_TIME	50
+
+/**
+ * omap_rtc_wait_not_busy - Wait for the RTC BUSY flag
+ * @oh: struct omap_hwmod *
+ *
+ * For updating certain RTC registers, the MPU must wait
+ * for the BUSY status in OMAP_RTC_STATUS_REG to become zero.
+ * Once the BUSY status is zero, there is a 15 microseconds access
+ * period in which the MPU can program.
+ */
+static void omap_rtc_wait_not_busy(struct omap_hwmod *oh)
+{
+	int i;
+
+	/* BUSY may stay active for 1/32768 second (~30 usec) */
+	omap_test_timeout(omap_hwmod_read(oh, OMAP_RTC_STATUS_REG)
+			  & OMAP_RTC_STATUS_BUSY, OMAP_RTC_MAX_READY_TIME, i);
+	/* now we have ~15 microseconds to read/write various registers */
+}
+
+/**
+ * omap_hwmod_rtc_unlock - Unlock the Kicker mechanism.
+ * @oh: struct omap_hwmod *
+ *
+ * RTC IP have kicker feature. This prevents spurious writes to its registers.
+ * In order to write into any of the RTC registers, KICK values has te be
+ * written in respective KICK registers. This is needed for hwmod to write into
+ * sysconfig register.
+ */
+void omap_hwmod_rtc_unlock(struct omap_hwmod *oh)
+{
+	unsigned long flags;
+
+	local_irq_save(flags);
+	omap_rtc_wait_not_busy(oh);
+	omap_hwmod_write(OMAP_RTC_KICK0_VALUE, oh, OMAP_RTC_KICK0_REG);
+	omap_hwmod_write(OMAP_RTC_KICK1_VALUE, oh, OMAP_RTC_KICK1_REG);
+	local_irq_restore(flags);
+}
+
+/**
+ * omap_hwmod_rtc_lock - Lock the Kicker mechanism.
+ * @oh: struct omap_hwmod *
+ *
+ * RTC IP have kicker feature. This prevents spurious writes to its registers.
+ * Once the RTC registers are written, KICK mechanism needs to be locked,
+ * in order to prevent any spurious writes. This function locks back the RTC
+ * registers once hwmod completes its write into sysconfig register.
+ */
+void omap_hwmod_rtc_lock(struct omap_hwmod *oh)
+{
+	unsigned long flags;
+
+	local_irq_save(flags);
+	omap_rtc_wait_not_busy(oh);
+	omap_hwmod_write(0x0, oh, OMAP_RTC_KICK0_REG);
+	omap_hwmod_write(0x0, oh, OMAP_RTC_KICK1_REG);
+	local_irq_restore(flags);
+}