linux/arch/arm/mach-omap2/pm34xx.c
Dave Gerlach 1560d15861 ARM: OMAP3: Fix external abort on 36xx waking from off mode idle
Depending on timing during the resume path from off mode on 36xx, we may
see external aborts. These seem to be caused by the following:

- OMAP3 Advisory 1.62 "MPU Cannot Exit from Standby" says we need to
  disable intc autoidle before WFI

- DM3730 Advisory 1.106 "MPU Leaves MSTANDBY State Before IDLEREQ of
  Interrupt Controller is Released" says we need to wait before
  accessing intc

omap3_intc_resume_idle restores the intc autoidle for all resume paths,
however in the resume path from off mode only it is also being restored
by omap_intc_restore_context before this call to omap3_intc_resume_idle
happens. The second restore of the intc autoidle in this path is what
appears to be causing the external abort so for the off mode resume path
let's rely on omap_intc_restore_context to restore intc autoidle, and
for all other paths let omap3_intc_resume_idle handle it as it is now.

Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
2016-04-14 08:27:30 -07:00

584 lines
15 KiB
C

/*
* OMAP3 Power Management Routines
*
* Copyright (C) 2006-2008 Nokia Corporation
* Tony Lindgren <tony@atomide.com>
* Jouni Hogander
*
* Copyright (C) 2007 Texas Instruments, Inc.
* Rajendra Nayak <rnayak@ti.com>
*
* Copyright (C) 2005 Texas Instruments, Inc.
* Richard Woodruff <r-woodruff2@ti.com>
*
* Based on pm.c for omap1
*
* 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/pm.h>
#include <linux/suspend.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/list.h>
#include <linux/err.h>
#include <linux/gpio.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/omap-dma.h>
#include <linux/omap-gpmc.h>
#include <linux/platform_data/gpio-omap.h>
#include <trace/events/power.h>
#include <asm/fncpy.h>
#include <asm/suspend.h>
#include <asm/system_misc.h>
#include "clockdomain.h"
#include "powerdomain.h"
#include "soc.h"
#include "common.h"
#include "cm3xxx.h"
#include "cm-regbits-34xx.h"
#include "prm-regbits-34xx.h"
#include "prm3xxx.h"
#include "pm.h"
#include "sdrc.h"
#include "sram.h"
#include "control.h"
#include "vc.h"
/* pm34xx errata defined in pm.h */
u16 pm34xx_errata;
struct power_state {
struct powerdomain *pwrdm;
u32 next_state;
#ifdef CONFIG_SUSPEND
u32 saved_state;
#endif
struct list_head node;
};
static LIST_HEAD(pwrst_list);
static int (*_omap_save_secure_sram)(u32 *addr);
void (*omap3_do_wfi_sram)(void);
static struct powerdomain *mpu_pwrdm, *neon_pwrdm;
static struct powerdomain *core_pwrdm, *per_pwrdm;
static void omap3_core_save_context(void)
{
omap3_ctrl_save_padconf();
/*
* Force write last pad into memory, as this can fail in some
* cases according to errata 1.157, 1.185
*/
omap_ctrl_writel(omap_ctrl_readl(OMAP343X_PADCONF_ETK_D14),
OMAP343X_CONTROL_MEM_WKUP + 0x2a0);
/* Save the Interrupt controller context */
omap_intc_save_context();
/* Save the GPMC context */
omap3_gpmc_save_context();
/* Save the system control module context, padconf already save above*/
omap3_control_save_context();
omap_dma_global_context_save();
}
static void omap3_core_restore_context(void)
{
/* Restore the control module context, padconf restored by h/w */
omap3_control_restore_context();
/* Restore the GPMC context */
omap3_gpmc_restore_context();
/* Restore the interrupt controller context */
omap_intc_restore_context();
omap_dma_global_context_restore();
}
/*
* FIXME: This function should be called before entering off-mode after
* OMAP3 secure services have been accessed. Currently it is only called
* once during boot sequence, but this works as we are not using secure
* services.
*/
static void omap3_save_secure_ram_context(void)
{
u32 ret;
int mpu_next_state = pwrdm_read_next_pwrst(mpu_pwrdm);
if (omap_type() != OMAP2_DEVICE_TYPE_GP) {
/*
* MPU next state must be set to POWER_ON temporarily,
* otherwise the WFI executed inside the ROM code
* will hang the system.
*/
pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
ret = _omap_save_secure_sram((u32 *)(unsigned long)
__pa(omap3_secure_ram_storage));
pwrdm_set_next_pwrst(mpu_pwrdm, mpu_next_state);
/* Following is for error tracking, it should not happen */
if (ret) {
pr_err("save_secure_sram() returns %08x\n", ret);
while (1)
;
}
}
}
static irqreturn_t _prcm_int_handle_io(int irq, void *unused)
{
int c;
c = omap_prm_clear_mod_irqs(WKUP_MOD, 1, OMAP3430_ST_IO_MASK |
OMAP3430_ST_IO_CHAIN_MASK);
return c ? IRQ_HANDLED : IRQ_NONE;
}
static irqreturn_t _prcm_int_handle_wakeup(int irq, void *unused)
{
int c;
/*
* Clear all except ST_IO and ST_IO_CHAIN for wkup module,
* these are handled in a separate handler to avoid acking
* IO events before parsing in mux code
*/
c = omap_prm_clear_mod_irqs(WKUP_MOD, 1, ~(OMAP3430_ST_IO_MASK |
OMAP3430_ST_IO_CHAIN_MASK));
c += omap_prm_clear_mod_irqs(CORE_MOD, 1, ~0);
c += omap_prm_clear_mod_irqs(OMAP3430_PER_MOD, 1, ~0);
if (omap_rev() > OMAP3430_REV_ES1_0) {
c += omap_prm_clear_mod_irqs(CORE_MOD, 3, ~0);
c += omap_prm_clear_mod_irqs(OMAP3430ES2_USBHOST_MOD, 1, ~0);
}
return c ? IRQ_HANDLED : IRQ_NONE;
}
static void omap34xx_save_context(u32 *save)
{
u32 val;
/* Read Auxiliary Control Register */
asm("mrc p15, 0, %0, c1, c0, 1" : "=r" (val));
*save++ = 1;
*save++ = val;
/* Read L2 AUX ctrl register */
asm("mrc p15, 1, %0, c9, c0, 2" : "=r" (val));
*save++ = 1;
*save++ = val;
}
static int omap34xx_do_sram_idle(unsigned long save_state)
{
omap34xx_cpu_suspend(save_state);
return 0;
}
void omap_sram_idle(void)
{
/* Variable to tell what needs to be saved and restored
* in omap_sram_idle*/
/* save_state = 0 => Nothing to save and restored */
/* save_state = 1 => Only L1 and logic lost */
/* save_state = 2 => Only L2 lost */
/* save_state = 3 => L1, L2 and logic lost */
int save_state = 0;
int mpu_next_state = PWRDM_POWER_ON;
int per_next_state = PWRDM_POWER_ON;
int core_next_state = PWRDM_POWER_ON;
int per_going_off;
u32 sdrc_pwr = 0;
mpu_next_state = pwrdm_read_next_pwrst(mpu_pwrdm);
switch (mpu_next_state) {
case PWRDM_POWER_ON:
case PWRDM_POWER_RET:
/* No need to save context */
save_state = 0;
break;
case PWRDM_POWER_OFF:
save_state = 3;
break;
default:
/* Invalid state */
pr_err("Invalid mpu state in sram_idle\n");
return;
}
/* NEON control */
if (pwrdm_read_pwrst(neon_pwrdm) == PWRDM_POWER_ON)
pwrdm_set_next_pwrst(neon_pwrdm, mpu_next_state);
/* Enable IO-PAD and IO-CHAIN wakeups */
per_next_state = pwrdm_read_next_pwrst(per_pwrdm);
core_next_state = pwrdm_read_next_pwrst(core_pwrdm);
pwrdm_pre_transition(NULL);
/* PER */
if (per_next_state < PWRDM_POWER_ON) {
per_going_off = (per_next_state == PWRDM_POWER_OFF) ? 1 : 0;
omap2_gpio_prepare_for_idle(per_going_off);
}
/* CORE */
if (core_next_state < PWRDM_POWER_ON) {
if (core_next_state == PWRDM_POWER_OFF) {
omap3_core_save_context();
omap3_cm_save_context();
}
}
/* Configure PMIC signaling for I2C4 or sys_off_mode */
omap3_vc_set_pmic_signaling(core_next_state);
omap3_intc_prepare_idle();
/*
* On EMU/HS devices ROM code restores a SRDC value
* from scratchpad which has automatic self refresh on timeout
* of AUTO_CNT = 1 enabled. This takes care of erratum ID i443.
* Hence store/restore the SDRC_POWER register here.
*/
if (cpu_is_omap3430() && omap_rev() >= OMAP3430_REV_ES3_0 &&
(omap_type() == OMAP2_DEVICE_TYPE_EMU ||
omap_type() == OMAP2_DEVICE_TYPE_SEC) &&
core_next_state == PWRDM_POWER_OFF)
sdrc_pwr = sdrc_read_reg(SDRC_POWER);
/*
* omap3_arm_context is the location where some ARM context
* get saved. The rest is placed on the stack, and restored
* from there before resuming.
*/
if (save_state)
omap34xx_save_context(omap3_arm_context);
if (save_state == 1 || save_state == 3)
cpu_suspend(save_state, omap34xx_do_sram_idle);
else
omap34xx_do_sram_idle(save_state);
/* Restore normal SDRC POWER settings */
if (cpu_is_omap3430() && omap_rev() >= OMAP3430_REV_ES3_0 &&
(omap_type() == OMAP2_DEVICE_TYPE_EMU ||
omap_type() == OMAP2_DEVICE_TYPE_SEC) &&
core_next_state == PWRDM_POWER_OFF)
sdrc_write_reg(sdrc_pwr, SDRC_POWER);
/* CORE */
if (core_next_state < PWRDM_POWER_ON &&
pwrdm_read_prev_pwrst(core_pwrdm) == PWRDM_POWER_OFF) {
omap3_core_restore_context();
omap3_cm_restore_context();
omap3_sram_restore_context();
omap2_sms_restore_context();
} else {
/*
* In off-mode resume path above, omap3_core_restore_context
* also handles the INTC autoidle restore done here so limit
* this to non-off mode resume paths so we don't do it twice.
*/
omap3_intc_resume_idle();
}
pwrdm_post_transition(NULL);
/* PER */
if (per_next_state < PWRDM_POWER_ON)
omap2_gpio_resume_after_idle();
}
static void omap3_pm_idle(void)
{
if (omap_irq_pending())
return;
trace_cpu_idle_rcuidle(1, smp_processor_id());
omap_sram_idle();
trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, smp_processor_id());
}
#ifdef CONFIG_SUSPEND
static int omap3_pm_suspend(void)
{
struct power_state *pwrst;
int state, ret = 0;
/* Read current next_pwrsts */
list_for_each_entry(pwrst, &pwrst_list, node)
pwrst->saved_state = pwrdm_read_next_pwrst(pwrst->pwrdm);
/* Set ones wanted by suspend */
list_for_each_entry(pwrst, &pwrst_list, node) {
if (omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state))
goto restore;
if (pwrdm_clear_all_prev_pwrst(pwrst->pwrdm))
goto restore;
}
omap3_intc_suspend();
omap_sram_idle();
restore:
/* Restore next_pwrsts */
list_for_each_entry(pwrst, &pwrst_list, node) {
state = pwrdm_read_prev_pwrst(pwrst->pwrdm);
if (state > pwrst->next_state) {
pr_info("Powerdomain (%s) didn't enter target state %d\n",
pwrst->pwrdm->name, pwrst->next_state);
ret = -1;
}
omap_set_pwrdm_state(pwrst->pwrdm, pwrst->saved_state);
}
if (ret)
pr_err("Could not enter target state in pm_suspend\n");
else
pr_info("Successfully put all powerdomains to target state\n");
return ret;
}
#else
#define omap3_pm_suspend NULL
#endif /* CONFIG_SUSPEND */
static void __init prcm_setup_regs(void)
{
omap3_ctrl_init();
omap3_prm_init_pm(cpu_is_omap3630(), omap3_has_iva());
}
void omap3_pm_off_mode_enable(int enable)
{
struct power_state *pwrst;
u32 state;
if (enable)
state = PWRDM_POWER_OFF;
else
state = PWRDM_POWER_RET;
list_for_each_entry(pwrst, &pwrst_list, node) {
if (IS_PM34XX_ERRATUM(PM_SDRC_WAKEUP_ERRATUM_i583) &&
pwrst->pwrdm == core_pwrdm &&
state == PWRDM_POWER_OFF) {
pwrst->next_state = PWRDM_POWER_RET;
pr_warn("%s: Core OFF disabled due to errata i583\n",
__func__);
} else {
pwrst->next_state = state;
}
omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state);
}
}
int omap3_pm_get_suspend_state(struct powerdomain *pwrdm)
{
struct power_state *pwrst;
list_for_each_entry(pwrst, &pwrst_list, node) {
if (pwrst->pwrdm == pwrdm)
return pwrst->next_state;
}
return -EINVAL;
}
int omap3_pm_set_suspend_state(struct powerdomain *pwrdm, int state)
{
struct power_state *pwrst;
list_for_each_entry(pwrst, &pwrst_list, node) {
if (pwrst->pwrdm == pwrdm) {
pwrst->next_state = state;
return 0;
}
}
return -EINVAL;
}
static int __init pwrdms_setup(struct powerdomain *pwrdm, void *unused)
{
struct power_state *pwrst;
if (!pwrdm->pwrsts)
return 0;
pwrst = kmalloc(sizeof(struct power_state), GFP_ATOMIC);
if (!pwrst)
return -ENOMEM;
pwrst->pwrdm = pwrdm;
pwrst->next_state = PWRDM_POWER_RET;
list_add(&pwrst->node, &pwrst_list);
if (pwrdm_has_hdwr_sar(pwrdm))
pwrdm_enable_hdwr_sar(pwrdm);
return omap_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state);
}
/*
* Push functions to SRAM
*
* The minimum set of functions is pushed to SRAM for execution:
* - omap3_do_wfi for erratum i581 WA,
* - save_secure_ram_context for security extensions.
*/
void omap_push_sram_idle(void)
{
omap3_do_wfi_sram = omap_sram_push(omap3_do_wfi, omap3_do_wfi_sz);
if (omap_type() != OMAP2_DEVICE_TYPE_GP)
_omap_save_secure_sram = omap_sram_push(save_secure_ram_context,
save_secure_ram_context_sz);
}
static void __init pm_errata_configure(void)
{
if (cpu_is_omap3630()) {
pm34xx_errata |= PM_RTA_ERRATUM_i608;
/* Enable the l2 cache toggling in sleep logic */
enable_omap3630_toggle_l2_on_restore();
if (omap_rev() < OMAP3630_REV_ES1_2)
pm34xx_errata |= (PM_SDRC_WAKEUP_ERRATUM_i583 |
PM_PER_MEMORIES_ERRATUM_i582);
} else if (cpu_is_omap34xx()) {
pm34xx_errata |= PM_PER_MEMORIES_ERRATUM_i582;
}
}
int __init omap3_pm_init(void)
{
struct power_state *pwrst, *tmp;
struct clockdomain *neon_clkdm, *mpu_clkdm, *per_clkdm, *wkup_clkdm;
int ret;
if (!omap3_has_io_chain_ctrl())
pr_warn("PM: no software I/O chain control; some wakeups may be lost\n");
pm_errata_configure();
/* XXX prcm_setup_regs needs to be before enabling hw
* supervised mode for powerdomains */
prcm_setup_regs();
ret = request_irq(omap_prcm_event_to_irq("wkup"),
_prcm_int_handle_wakeup, IRQF_NO_SUSPEND, "pm_wkup", NULL);
if (ret) {
pr_err("pm: Failed to request pm_wkup irq\n");
goto err1;
}
/* IO interrupt is shared with mux code */
ret = request_irq(omap_prcm_event_to_irq("io"),
_prcm_int_handle_io, IRQF_SHARED | IRQF_NO_SUSPEND, "pm_io",
omap3_pm_init);
enable_irq(omap_prcm_event_to_irq("io"));
if (ret) {
pr_err("pm: Failed to request pm_io irq\n");
goto err2;
}
ret = pwrdm_for_each(pwrdms_setup, NULL);
if (ret) {
pr_err("Failed to setup powerdomains\n");
goto err3;
}
(void) clkdm_for_each(omap_pm_clkdms_setup, NULL);
mpu_pwrdm = pwrdm_lookup("mpu_pwrdm");
if (mpu_pwrdm == NULL) {
pr_err("Failed to get mpu_pwrdm\n");
ret = -EINVAL;
goto err3;
}
neon_pwrdm = pwrdm_lookup("neon_pwrdm");
per_pwrdm = pwrdm_lookup("per_pwrdm");
core_pwrdm = pwrdm_lookup("core_pwrdm");
neon_clkdm = clkdm_lookup("neon_clkdm");
mpu_clkdm = clkdm_lookup("mpu_clkdm");
per_clkdm = clkdm_lookup("per_clkdm");
wkup_clkdm = clkdm_lookup("wkup_clkdm");
omap_common_suspend_init(omap3_pm_suspend);
arm_pm_idle = omap3_pm_idle;
omap3_idle_init();
/*
* RTA is disabled during initialization as per erratum i608
* it is safer to disable RTA by the bootloader, but we would like
* to be doubly sure here and prevent any mishaps.
*/
if (IS_PM34XX_ERRATUM(PM_RTA_ERRATUM_i608))
omap3630_ctrl_disable_rta();
/*
* The UART3/4 FIFO and the sidetone memory in McBSP2/3 are
* not correctly reset when the PER powerdomain comes back
* from OFF or OSWR when the CORE powerdomain is kept active.
* See OMAP36xx Erratum i582 "PER Domain reset issue after
* Domain-OFF/OSWR Wakeup". This wakeup dependency is not a
* complete workaround. The kernel must also prevent the PER
* powerdomain from going to OSWR/OFF while the CORE
* powerdomain is not going to OSWR/OFF. And if PER last
* power state was off while CORE last power state was ON, the
* UART3/4 and McBSP2/3 SIDETONE devices need to run a
* self-test using their loopback tests; if that fails, those
* devices are unusable until the PER/CORE can complete a transition
* from ON to OSWR/OFF and then back to ON.
*
* XXX Technically this workaround is only needed if off-mode
* or OSWR is enabled.
*/
if (IS_PM34XX_ERRATUM(PM_PER_MEMORIES_ERRATUM_i582))
clkdm_add_wkdep(per_clkdm, wkup_clkdm);
clkdm_add_wkdep(neon_clkdm, mpu_clkdm);
if (omap_type() != OMAP2_DEVICE_TYPE_GP) {
omap3_secure_ram_storage =
kmalloc(0x803F, GFP_KERNEL);
if (!omap3_secure_ram_storage)
pr_err("Memory allocation failed when allocating for secure sram context\n");
local_irq_disable();
omap_dma_global_context_save();
omap3_save_secure_ram_context();
omap_dma_global_context_restore();
local_irq_enable();
}
omap3_save_scratchpad_contents();
return ret;
err3:
list_for_each_entry_safe(pwrst, tmp, &pwrst_list, node) {
list_del(&pwrst->node);
kfree(pwrst);
}
free_irq(omap_prcm_event_to_irq("io"), omap3_pm_init);
err2:
free_irq(omap_prcm_event_to_irq("wkup"), NULL);
err1:
return ret;
}