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-rw-r--r--arch/arm/mach-omap2/cm_common.c140
1 files changed, 140 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/cm_common.c b/arch/arm/mach-omap2/cm_common.c
new file mode 100644
index 00000000000..40b3b5a8445
--- /dev/null
+++ b/arch/arm/mach-omap2/cm_common.c
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+/*
+ * OMAP2+ common Clock Management (CM) IP block functions
+ *
+ * Copyright (C) 2012 Texas Instruments, Inc.
+ * 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.
+ *
+ * XXX This code should eventually be moved to a CM driver.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/errno.h>
+
+#include "cm2xxx.h"
+#include "cm3xxx.h"
+#include "cm44xx.h"
+#include "common.h"
+
+/*
+ * cm_ll_data: function pointers to SoC-specific implementations of
+ * common CM functions
+ */
+static struct cm_ll_data null_cm_ll_data;
+static struct cm_ll_data *cm_ll_data = &null_cm_ll_data;
+
+/* cm_base: base virtual address of the CM IP block */
+void __iomem *cm_base;
+
+/* cm2_base: base virtual address of the CM2 IP block (OMAP44xx only) */
+void __iomem *cm2_base;
+
+/**
+ * omap2_set_globals_cm - set the CM/CM2 base addresses (for early use)
+ * @cm: CM base virtual address
+ * @cm2: CM2 base virtual address (if present on the booted SoC)
+ *
+ * XXX Will be replaced when the PRM/CM drivers are completed.
+ */
+void __init omap2_set_globals_cm(void __iomem *cm, void __iomem *cm2)
+{
+ cm_base = cm;
+ cm2_base = cm2;
+}
+
+/**
+ * cm_split_idlest_reg - split CM_IDLEST reg addr into its components
+ * @idlest_reg: CM_IDLEST* virtual address
+ * @prcm_inst: pointer to an s16 to return the PRCM instance offset
+ * @idlest_reg_id: pointer to a u8 to return the CM_IDLESTx register ID
+ *
+ * Given an absolute CM_IDLEST register address @idlest_reg, passes
+ * the PRCM instance offset and IDLEST register ID back to the caller
+ * via the @prcm_inst and @idlest_reg_id. Returns -EINVAL upon error,
+ * or 0 upon success. XXX This function is only needed until absolute
+ * register addresses are removed from the OMAP struct clk records.
+ */
+int cm_split_idlest_reg(void __iomem *idlest_reg, s16 *prcm_inst,
+ u8 *idlest_reg_id)
+{
+ if (!cm_ll_data->split_idlest_reg) {
+ WARN_ONCE(1, "cm: %s: no low-level function defined\n",
+ __func__);
+ return -EINVAL;
+ }
+
+ return cm_ll_data->split_idlest_reg(idlest_reg, prcm_inst,
+ idlest_reg_id);
+}
+
+/**
+ * cm_wait_module_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
+ *
+ * Wait for the PRCM to indicate that the module identified by
+ * (@prcm_mod, @idlest_id, @idlest_shift) is clocked. Return 0 upon
+ * success, -EBUSY if the module doesn't enable in time, or -EINVAL if
+ * no per-SoC wait_module_ready() function pointer has been registered
+ * or if the idlest register is unknown on the SoC.
+ */
+int cm_wait_module_ready(s16 prcm_mod, u8 idlest_id, u8 idlest_shift)
+{
+ if (!cm_ll_data->wait_module_ready) {
+ WARN_ONCE(1, "cm: %s: no low-level function defined\n",
+ __func__);
+ return -EINVAL;
+ }
+
+ return cm_ll_data->wait_module_ready(prcm_mod, idlest_id, idlest_shift);
+}
+
+/**
+ * cm_register - register per-SoC low-level data with the CM
+ * @cld: low-level per-SoC OMAP CM data & function pointers to register
+ *
+ * Register per-SoC low-level OMAP CM data and function pointers with
+ * the OMAP CM common interface. The caller must keep the data
+ * pointed to by @cld valid until it calls cm_unregister() and
+ * it returns successfully. Returns 0 upon success, -EINVAL if @cld
+ * is NULL, or -EEXIST if cm_register() has already been called
+ * without an intervening cm_unregister().
+ */
+int cm_register(struct cm_ll_data *cld)
+{
+ if (!cld)
+ return -EINVAL;
+
+ if (cm_ll_data != &null_cm_ll_data)
+ return -EEXIST;
+
+ cm_ll_data = cld;
+
+ return 0;
+}
+
+/**
+ * cm_unregister - unregister per-SoC low-level data & function pointers
+ * @cld: low-level per-SoC OMAP CM data & function pointers to unregister
+ *
+ * Unregister per-SoC low-level OMAP CM data and function pointers
+ * that were previously registered with cm_register(). The
+ * caller may not destroy any of the data pointed to by @cld until
+ * this function returns successfully. Returns 0 upon success, or
+ * -EINVAL if @cld is NULL or if @cld does not match the struct
+ * cm_ll_data * previously registered by cm_register().
+ */
+int cm_unregister(struct cm_ll_data *cld)
+{
+ if (!cld || cm_ll_data != cld)
+ return -EINVAL;
+
+ cm_ll_data = &null_cm_ll_data;
+
+ return 0;
+}