kernel-ark/arch/arm/mach-omap2/prm2xxx.c
Paul Walmsley 2bb2a5d30a ARM: OMAP2+: PRM: create PRM reset source API for the watchdog timer driver
The OMAP watchdog timer driver needs to determine what caused the SoC
to reset for its GETBOOTSTATUS ioctl.  So, define a set of standard
reset sources across OMAP SoCs.  For OMAP2xxx, 3xxx, and 4xxx SoCs,
define mappings from the SoC-specific reset source register bits to
the standardized reset source IDs.  Create SoC-specific PRM functions
that read the appropriate per-SoC register and use the mapping to
return the standardized reset bits.  Register the SoC-specific PRM
functions with the common PRM code via prm_register().  Create a
function in the common PRM code, prm_read_reset_sources(), that
calls the SoC-specific function, registered during boot.

This patch does not yet handle some SoCs, such as AM33xx.  Those SoCs
were not handled by the code this will replace.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
2012-10-21 01:01:13 -06:00

127 lines
3.3 KiB
C

/*
* OMAP2xxx PRM module functions
*
* Copyright (C) 2010-2012 Texas Instruments, Inc.
* Copyright (C) 2010 Nokia Corporation
* Benoît Cousson
* Paul Walmsley
* Rajendra Nayak <rnayak@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/kernel.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/irq.h>
#include "common.h"
#include <plat/cpu.h>
#include <plat/prcm.h>
#include "vp.h"
#include "powerdomain.h"
#include "clockdomain.h"
#include "prm2xxx.h"
#include "cm2xxx_3xxx.h"
#include "prm-regbits-24xx.h"
/*
* omap2xxx_prm_reset_src_map - map from bits in the PRM_RSTST_WKUP
* hardware register (which are specific to the OMAP2xxx SoCs) to
* reset source ID bit shifts (which is an OMAP SoC-independent
* enumeration)
*/
static struct prm_reset_src_map omap2xxx_prm_reset_src_map[] = {
{ OMAP_GLOBALCOLD_RST_SHIFT, OMAP_GLOBAL_COLD_RST_SRC_ID_SHIFT },
{ OMAP_GLOBALWARM_RST_SHIFT, OMAP_GLOBAL_WARM_RST_SRC_ID_SHIFT },
{ OMAP24XX_SECU_VIOL_RST_SHIFT, OMAP_SECU_VIOL_RST_SRC_ID_SHIFT },
{ OMAP24XX_MPU_WD_RST_SHIFT, OMAP_MPU_WD_RST_SRC_ID_SHIFT },
{ OMAP24XX_SECU_WD_RST_SHIFT, OMAP_SECU_WD_RST_SRC_ID_SHIFT },
{ OMAP24XX_EXTWMPU_RST_SHIFT, OMAP_EXTWARM_RST_SRC_ID_SHIFT },
{ -1, -1 },
};
/**
* omap2xxx_prm_read_reset_sources - return the last SoC reset source
*
* Return a u32 representing the last reset sources of the SoC. The
* returned reset source bits are standardized across OMAP SoCs.
*/
static u32 omap2xxx_prm_read_reset_sources(void)
{
struct prm_reset_src_map *p;
u32 r = 0;
u32 v;
v = omap2_prm_read_mod_reg(WKUP_MOD, OMAP2_RM_RSTST);
p = omap2xxx_prm_reset_src_map;
while (p->reg_shift >= 0 && p->std_shift >= 0) {
if (v & (1 << p->reg_shift))
r |= 1 << p->std_shift;
p++;
}
return r;
}
int omap2xxx_clkdm_sleep(struct clockdomain *clkdm)
{
omap2_prm_set_mod_reg_bits(OMAP24XX_FORCESTATE_MASK,
clkdm->pwrdm.ptr->prcm_offs,
OMAP2_PM_PWSTCTRL);
return 0;
}
int omap2xxx_clkdm_wakeup(struct clockdomain *clkdm)
{
omap2_prm_clear_mod_reg_bits(OMAP24XX_FORCESTATE_MASK,
clkdm->pwrdm.ptr->prcm_offs,
OMAP2_PM_PWSTCTRL);
return 0;
}
struct pwrdm_ops omap2_pwrdm_operations = {
.pwrdm_set_next_pwrst = omap2_pwrdm_set_next_pwrst,
.pwrdm_read_next_pwrst = omap2_pwrdm_read_next_pwrst,
.pwrdm_read_pwrst = omap2_pwrdm_read_pwrst,
.pwrdm_set_logic_retst = omap2_pwrdm_set_logic_retst,
.pwrdm_set_mem_onst = omap2_pwrdm_set_mem_onst,
.pwrdm_set_mem_retst = omap2_pwrdm_set_mem_retst,
.pwrdm_read_mem_pwrst = omap2_pwrdm_read_mem_pwrst,
.pwrdm_read_mem_retst = omap2_pwrdm_read_mem_retst,
.pwrdm_wait_transition = omap2_pwrdm_wait_transition,
};
/*
*
*/
static struct prm_ll_data omap2xxx_prm_ll_data = {
.read_reset_sources = &omap2xxx_prm_read_reset_sources,
};
static int __init omap2xxx_prm_init(void)
{
if (!cpu_is_omap24xx())
return 0;
return prm_register(&omap2xxx_prm_ll_data);
}
subsys_initcall(omap2xxx_prm_init);
static void __exit omap2xxx_prm_exit(void)
{
if (!cpu_is_omap24xx())
return;
/* Should never happen */
WARN(prm_unregister(&omap2xxx_prm_ll_data),
"%s: prm_ll_data function pointer mismatch\n", __func__);
}
__exitcall(omap2xxx_prm_exit);