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-rw-r--r--arch/arm/mach-omap2/cm4xxx.c68
1 files changed, 68 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/cm4xxx.c b/arch/arm/mach-omap2/cm4xxx.c
new file mode 100644
index 00000000000..e4ebd6d5313
--- /dev/null
+++ b/arch/arm/mach-omap2/cm4xxx.c
@@ -0,0 +1,68 @@
+/*
+ * OMAP4 CM module functions
+ *
+ * Copyright (C) 2009 Nokia Corporation
+ * Paul Walmsley
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/delay.h>
+#include <linux/spinlock.h>
+#include <linux/list.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/io.h>
+
+#include <asm/atomic.h>
+
+#include "cm.h"
+#include "cm-regbits-4xxx.h"
+
+/* XXX move this to cm.h */
+/* MAX_MODULE_READY_TIME: max milliseconds for module to leave idle */
+#define MAX_MODULE_READY_TIME 20000
+
+/*
+ * OMAP4_PRCM_CM_CLKCTRL_IDLEST_MASK: isolates the IDLEST field in the
+ * CM_CLKCTRL register.
+ */
+#define OMAP4_PRCM_CM_CLKCTRL_IDLEST_MASK (0x2 << 16)
+
+/*
+ * OMAP4 prcm_mod u32 fields contain packed data: the CM ID in bit 16 and
+ * the PRCM module offset address (from the CM module base) in bits 15-0.
+ */
+#define OMAP4_PRCM_MOD_CM_ID_SHIFT 16
+#define OMAP4_PRCM_MOD_OFFS_MASK 0xffff
+
+/**
+ * omap4_cm_wait_idlest_ready - wait for a module to leave idle or standby
+ * @prcm_mod: PRCM module offset (XXX example)
+ * @prcm_dev_offs: PRCM device offset (e.g. MCASP XXX example)
+ *
+ * XXX document
+ */
+int omap4_cm_wait_idlest_ready(u32 prcm_mod, u8 prcm_dev_offs)
+{
+ int i = 0;
+ u8 cm_id;
+ u16 prcm_mod_offs;
+ u32 mask = OMAP4_PRCM_CM_CLKCTRL_IDLEST_MASK;
+
+ cm_id = prcm_mod >> OMAP4_PRCM_MOD_CM_ID_SHIFT;
+ prcm_mod_offs = prcm_mod & OMAP4_PRCM_MOD_OFFS_MASK;
+
+ while (((omap4_cm_read_mod_reg(cm_id, prcm_mod_offs, prcm_dev_offs,
+ OMAP4_CM_CLKCTRL_DREG) & mask) != 0) &&
+ (i++ < MAX_MODULE_READY_TIME))
+ udelay(1);
+
+ return (i < MAX_MODULE_READY_TIME) ? 0 : -EBUSY;
+}
+