linux/arch/arm/mach-omap2/prcm.c

137 lines
3.6 KiB
C
Raw Normal View History

/*
* linux/arch/arm/mach-omap2/prcm.c
*
* OMAP 24xx Power Reset and Clock Management (PRCM) functions
*
* Copyright (C) 2005 Nokia Corporation
*
* Written by Tony Lindgren <tony.lindgren@nokia.com>
*
* Copyright (C) 2007 Texas Instruments, Inc.
* Rajendra Nayak <rnayak@ti.com>
*
* Some pieces of code Copyright (C) 2005 Texas Instruments, Inc.
* Upgraded with OMAP4 support by Abhijit Pagare <abhijitpagare@ti.com>
*
* 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/module.h>
#include <linux/init.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/delay.h>
#include <plat/common.h>
#include <plat/prcm.h>
#include <plat/irqs.h>
#include "clock.h"
#include "clock2xxx.h"
#include "cm2xxx_3xxx.h"
#include "cm44xx.h"
#include "prm2xxx_3xxx.h"
#include "prm44xx.h"
OMAP4: PRCM: add OMAP4-specific accessor/mutator functions In some ways, the OMAP4 PRCM register layout is quite different than the OMAP2/3 PRCM register layout. For example, on OMAP2/3, from a register layout point of view, all CM instances were located in the CM subsystem, and all PRM instances were located in the PRM subsystem. OMAP4 changes this. Now, for example, some CM instances, such as WKUP_CM and EMU_CM, are located in the system PRM subsystem. And a "local PRCM" exists for the MPU - this PRCM combines registers that would normally appear in both CM and PRM instances, but uses its own register layout which matches neither the OMAP2/3 PRCM layout nor the OMAP4 PRCM layout. To try to deal with this, introduce some new functions, omap4_cminst* and omap4_prminst*. The former is to be used when writing to a CM instance register (no matter what subsystem or hardware module it exists in), and the latter, similarly, with PRM instance registers. To determine which "PRCM partition" to write to, the functions take a PRCM instance ID argument. Subsequent patches add these partition IDs to the OMAP4 powerdomain and clockdomain definitions. As far as I can see, there's really no good way to handle these types of register access inconsistencies. This patch seemed like the least bad approach. Moving forward, the long-term goal is to remove all direct PRCM register access from the PM code. PRCM register access should go through layers such as the powerdomain and clockdomain code that can hide the details of how to interact with the specific hardware variant. While here, rename cm4xxx.c to cm44xx.c to match the naming convention of the other OMAP4 PRCM files. Thanks to Santosh Shilimkar <santosh.shilimkar@ti.com>, Rajendra Nayak <rnayak@ti.com>, and Benoît Cousson <b-cousson@ti.com> for some comments. Signed-off-by: Paul Walmsley <paul@pwsan.com> Cc: Benoît Cousson <b-cousson@ti.com> Cc: Rajendra Nayak <rnayak@ti.com> Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
2010-12-22 04:05:14 +00:00
#include "prcm44xx.h"
#include "prm-regbits-24xx.h"
#include "prm-regbits-44xx.h"
#include "control.h"
void __iomem *prm_base;
void __iomem *cm_base;
void __iomem *cm2_base;
#define MAX_MODULE_ENABLE_WAIT 100000
u32 omap_prcm_get_reset_sources(void)
{
/* XXX This presumably needs modification for 34XX */
if (cpu_is_omap24xx() || cpu_is_omap34xx())
return prm_read_mod_reg(WKUP_MOD, OMAP2_RM_RSTST) & 0x7f;
if (cpu_is_omap44xx())
return prm_read_mod_reg(WKUP_MOD, OMAP4_RM_RSTST) & 0x7f;
return 0;
}
EXPORT_SYMBOL(omap_prcm_get_reset_sources);
/* Resets clock rates and reboots the system. Only called from system.h */
void omap_prcm_arch_reset(char mode, const char *cmd)
{
s16 prcm_offs = 0;
if (cpu_is_omap24xx()) {
omap2xxx_clk_prepare_for_reboot();
prcm_offs = WKUP_MOD;
} else if (cpu_is_omap34xx()) {
prcm_offs = OMAP3430_GR_MOD;
omap3_ctrl_write_boot_mode((cmd ? (u8)*cmd : 0));
} else if (cpu_is_omap44xx()) {
omap4_prm_global_warm_sw_reset(); /* never returns */
} else {
WARN_ON(1);
}
/* XXX should be moved to some OMAP2/3 specific code */
prm_set_mod_reg_bits(OMAP_RST_DPLL3_MASK, prcm_offs,
OMAP2_RM_RSTCTRL);
prm_read_mod_reg(prcm_offs, OMAP2_RM_RSTCTRL); /* OCP barrier */
}
/**
* omap2_cm_wait_idlest - wait for IDLEST bit to indicate module readiness
* @reg: physical address of module IDLEST register
* @mask: value to mask against to determine if the module is active
* @idlest: idle state indicator (0 or 1) for the clock
* @name: name of the clock (for printk)
*
* Returns 1 if the module indicated readiness in time, or 0 if it
* failed to enable in roughly MAX_MODULE_ENABLE_WAIT microseconds.
*
* XXX This function is deprecated. It should be removed once the
* hwmod conversion is complete.
*/
int omap2_cm_wait_idlest(void __iomem *reg, u32 mask, u8 idlest,
const char *name)
{
int i = 0;
int ena = 0;
if (idlest)
ena = 0;
else
ena = mask;
/* Wait for lock */
omap_test_timeout(((__raw_readl(reg) & mask) == ena),
MAX_MODULE_ENABLE_WAIT, i);
if (i < MAX_MODULE_ENABLE_WAIT)
pr_debug("cm: Module associated with clock %s ready after %d "
"loops\n", name, i);
else
pr_err("cm: Module associated with clock %s didn't enable in "
"%d tries\n", name, MAX_MODULE_ENABLE_WAIT);
return (i < MAX_MODULE_ENABLE_WAIT) ? 1 : 0;
};
void __init omap2_set_globals_prcm(struct omap_globals *omap2_globals)
{
/* Static mapping, never released */
if (omap2_globals->prm) {
prm_base = ioremap(omap2_globals->prm, SZ_8K);
WARN_ON(!prm_base);
}
if (omap2_globals->cm) {
cm_base = ioremap(omap2_globals->cm, SZ_8K);
WARN_ON(!cm_base);
}
if (omap2_globals->cm2) {
cm2_base = ioremap(omap2_globals->cm2, SZ_8K);
WARN_ON(!cm2_base);
}
}