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Diffstat (limited to 'arch/arm/mach-omap2/cm.c')
-rw-r--r--arch/arm/mach-omap2/cm.c70
1 files changed, 70 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/cm.c b/arch/arm/mach-omap2/cm.c
new file mode 100644
index 000000000000..8eb2dab8c7db
--- /dev/null
+++ b/arch/arm/mach-omap2/cm.c
@@ -0,0 +1,70 @@
+/*
+ * OMAP2/3 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-24xx.h"
+#include "cm-regbits-34xx.h"
+
+/* MAX_MODULE_READY_TIME: max milliseconds for module to leave idle */
+#define MAX_MODULE_READY_TIME 20000
+
+static const u8 cm_idlest_offs[] = {
+ CM_IDLEST1, CM_IDLEST2, OMAP2430_CM_IDLEST3
+};
+
+/**
+ * omap2_cm_wait_idlest_ready - wait for a module to leave idle or standby
+ * @prcm_mod: PRCM module offset
+ * @idlest_id: CM_IDLESTx register ID (i.e., x = 1, 2, 3)
+ * @idlest_shift: shift of the bit in the CM_IDLEST* register to check
+ *
+ * XXX document
+ */
+int omap2_cm_wait_module_ready(s16 prcm_mod, u8 idlest_id, u8 idlest_shift)
+{
+ int ena = 0, i = 0;
+ u8 cm_idlest_reg;
+ u32 mask;
+
+ if (!idlest_id || (idlest_id > ARRAY_SIZE(cm_idlest_offs)))
+ return -EINVAL;
+
+ cm_idlest_reg = cm_idlest_offs[idlest_id - 1];
+
+ if (cpu_is_omap24xx())
+ ena = idlest_shift;
+ else if (cpu_is_omap34xx())
+ ena = 0;
+ else
+ BUG();
+
+ mask = 1 << idlest_shift;
+
+ /* XXX should be OMAP2 CM */
+ while (((cm_read_mod_reg(prcm_mod, cm_idlest_reg) & mask) != ena) &&
+ (i++ < MAX_MODULE_READY_TIME))
+ udelay(1);
+
+ return (i < MAX_MODULE_READY_TIME) ? 0 : -EBUSY;
+}
+