/*
* 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 <linux/bug.h>
#include "cm2xxx.h"
#include "cm3xxx.h"
#include "cm44xx.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);
}
/**
* omap_cm_wait_module_ready - wait for a module to leave idle or standby
* @part: PRCM partition
* @prcm_mod: PRCM module offset
* @idlest_reg: CM_IDLESTx register
* @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 omap_cm_wait_module_ready(u8 part, s16 prcm_mod, u16 idlest_reg,
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(part, prcm_mod, idlest_reg,
idlest_shift);
}
/**
* omap_cm_wait_module_idle - wait for a module to enter idle or standby
* @part: PRCM partition
* @prcm_mod: PRCM module offset
* @idlest_reg: CM_IDLESTx register
* @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 no longer clocked. Return
* 0 upon success, -EBUSY if the module doesn't enable in time, or
* -EINVAL if no per-SoC wait_module_idle() function pointer has been
* registered or if the idlest register is unknown on the SoC.
*/
int omap_cm_wait_module_idle(u8 part, s16 prcm_mod, u16 idlest_reg,
u8 idlest_shift)
{
if (!cm_ll_data->wait_module_idle) {
WARN_ONCE(1, "cm: %s: no low-level function defined\n",
__func__);
return -EINVAL;
}
return cm_ll_data->wait_module_idle(part, prcm_mod, idlest_reg,
idlest_shift);
}
/**
* omap_cm_module_enable - enable a module
* @mode: target mode for the module
* @part: PRCM partition
* @inst: PRCM instance
* @clkctrl_offs: CM_CLKCTRL register offset for the module
*
* Enables clocks for a module identified by (@part, @inst, @clkctrl_offs)
* making its IO space accessible. Return 0 upon success, -EINVAL if no
* per-SoC module_enable() function pointer has been registered.
*/
int omap_cm_module_enable(u8 mode, u8 part, u16 inst, u16 clkctrl_offs)
{
if (!cm_ll_data->module_enable) {
WARN_ONCE(1, "cm: %s: no low-level function defined\n",
__func__);
return -EINVAL;
}
cm_ll_data->module_enable(mode, part, inst, clkctrl_offs);
return 0;
}
/**
* omap_cm_module_disable - disable a module
* @part: PRCM partition
* @inst: PRCM instance
* @clkctrl_offs: CM_CLKCTRL register offset for the module
*
* Disables clocks for a module identified by (@part, @inst, @clkctrl_offs)
* makings its IO space inaccessible. Return 0 upon success, -EINVAL if
* no per-SoC module_disable() function pointer has been registered.
*/
int omap_cm_module_disable(u8 part, u16 inst, u16 clkctrl_offs)
{
if (!cm_ll_data->module_disable) {
WARN_ONCE(1, "cm: %s: no low-level function defined\n",
__func__);
return -EINVAL;
}
cm_ll_data->module_disable(part, inst, clkctrl_offs);
return 0;
}
/**
* 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;
}
