linux/arch/arm/mach-omap2/omap-wakeupgen.c
Rajendra Nayak 6099dd37c6 ARM: OMAP5 / DRA7: Enable CPU RET on suspend
On OMAP5 / DRA7, prevent a CPU powerdomain OFF and resulting MPU OSWR
and instead attempt a CPU RET and side effect, MPU RET in suspend.

NOTE: the hardware was originally designed to be capable of achieving
deep power states such as OFF and OSWR, however due to various issues
and risks, deepest valid state was determined to be CSWR - hence we use
the errata framework to handle this case.

Signed-off-by: Rajendra Nayak <rnayak@ti.com>
[nm@ti.com: updates]
Signed-off-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Tested-by: Kevin Hilman <khilman@linaro.org>
2014-09-08 11:38:43 -05:00

477 lines
12 KiB
C

/*
* OMAP WakeupGen Source file
*
* OMAP WakeupGen is the interrupt controller extension used along
* with ARM GIC to wake the CPU out from low power states on
* external interrupts. It is responsible for generating wakeup
* event from the incoming interrupts and enable bits. It is
* implemented in MPU always ON power domain. During normal operation,
* WakeupGen delivers external interrupts directly to the GIC.
*
* Copyright (C) 2011 Texas Instruments, Inc.
* Santosh Shilimkar <santosh.shilimkar@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/init.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/platform_device.h>
#include <linux/cpu.h>
#include <linux/notifier.h>
#include <linux/cpu_pm.h>
#include <linux/irqchip/arm-gic.h>
#include "omap-wakeupgen.h"
#include "omap-secure.h"
#include "soc.h"
#include "omap4-sar-layout.h"
#include "common.h"
#include "pm.h"
#define AM43XX_NR_REG_BANKS 7
#define AM43XX_IRQS 224
#define MAX_NR_REG_BANKS AM43XX_NR_REG_BANKS
#define MAX_IRQS AM43XX_IRQS
#define DEFAULT_NR_REG_BANKS 5
#define DEFAULT_IRQS 160
#define WKG_MASK_ALL 0x00000000
#define WKG_UNMASK_ALL 0xffffffff
#define CPU_ENA_OFFSET 0x400
#define CPU0_ID 0x0
#define CPU1_ID 0x1
#define OMAP4_NR_BANKS 4
#define OMAP4_NR_IRQS 128
static void __iomem *wakeupgen_base;
static void __iomem *sar_base;
static DEFINE_RAW_SPINLOCK(wakeupgen_lock);
static unsigned int irq_target_cpu[MAX_IRQS];
static unsigned int irq_banks = DEFAULT_NR_REG_BANKS;
static unsigned int max_irqs = DEFAULT_IRQS;
static unsigned int omap_secure_apis;
/*
* Static helper functions.
*/
static inline u32 wakeupgen_readl(u8 idx, u32 cpu)
{
return readl_relaxed(wakeupgen_base + OMAP_WKG_ENB_A_0 +
(cpu * CPU_ENA_OFFSET) + (idx * 4));
}
static inline void wakeupgen_writel(u32 val, u8 idx, u32 cpu)
{
writel_relaxed(val, wakeupgen_base + OMAP_WKG_ENB_A_0 +
(cpu * CPU_ENA_OFFSET) + (idx * 4));
}
static inline void sar_writel(u32 val, u32 offset, u8 idx)
{
writel_relaxed(val, sar_base + offset + (idx * 4));
}
static inline int _wakeupgen_get_irq_info(u32 irq, u32 *bit_posn, u8 *reg_index)
{
unsigned int spi_irq;
/*
* PPIs and SGIs are not supported.
*/
if (irq < OMAP44XX_IRQ_GIC_START)
return -EINVAL;
/*
* Subtract the GIC offset.
*/
spi_irq = irq - OMAP44XX_IRQ_GIC_START;
if (spi_irq > MAX_IRQS) {
pr_err("omap wakeupGen: Invalid IRQ%d\n", irq);
return -EINVAL;
}
/*
* Each WakeupGen register controls 32 interrupt.
* i.e. 1 bit per SPI IRQ
*/
*reg_index = spi_irq >> 5;
*bit_posn = spi_irq %= 32;
return 0;
}
static void _wakeupgen_clear(unsigned int irq, unsigned int cpu)
{
u32 val, bit_number;
u8 i;
if (_wakeupgen_get_irq_info(irq, &bit_number, &i))
return;
val = wakeupgen_readl(i, cpu);
val &= ~BIT(bit_number);
wakeupgen_writel(val, i, cpu);
}
static void _wakeupgen_set(unsigned int irq, unsigned int cpu)
{
u32 val, bit_number;
u8 i;
if (_wakeupgen_get_irq_info(irq, &bit_number, &i))
return;
val = wakeupgen_readl(i, cpu);
val |= BIT(bit_number);
wakeupgen_writel(val, i, cpu);
}
/*
* Architecture specific Mask extension
*/
static void wakeupgen_mask(struct irq_data *d)
{
unsigned long flags;
raw_spin_lock_irqsave(&wakeupgen_lock, flags);
_wakeupgen_clear(d->hwirq, irq_target_cpu[d->hwirq]);
raw_spin_unlock_irqrestore(&wakeupgen_lock, flags);
}
/*
* Architecture specific Unmask extension
*/
static void wakeupgen_unmask(struct irq_data *d)
{
unsigned long flags;
raw_spin_lock_irqsave(&wakeupgen_lock, flags);
_wakeupgen_set(d->hwirq, irq_target_cpu[d->hwirq]);
raw_spin_unlock_irqrestore(&wakeupgen_lock, flags);
}
#ifdef CONFIG_HOTPLUG_CPU
static DEFINE_PER_CPU(u32 [MAX_NR_REG_BANKS], irqmasks);
static void _wakeupgen_save_masks(unsigned int cpu)
{
u8 i;
for (i = 0; i < irq_banks; i++)
per_cpu(irqmasks, cpu)[i] = wakeupgen_readl(i, cpu);
}
static void _wakeupgen_restore_masks(unsigned int cpu)
{
u8 i;
for (i = 0; i < irq_banks; i++)
wakeupgen_writel(per_cpu(irqmasks, cpu)[i], i, cpu);
}
static void _wakeupgen_set_all(unsigned int cpu, unsigned int reg)
{
u8 i;
for (i = 0; i < irq_banks; i++)
wakeupgen_writel(reg, i, cpu);
}
/*
* Mask or unmask all interrupts on given CPU.
* 0 = Mask all interrupts on the 'cpu'
* 1 = Unmask all interrupts on the 'cpu'
* Ensure that the initial mask is maintained. This is faster than
* iterating through GIC registers to arrive at the correct masks.
*/
static void wakeupgen_irqmask_all(unsigned int cpu, unsigned int set)
{
unsigned long flags;
raw_spin_lock_irqsave(&wakeupgen_lock, flags);
if (set) {
_wakeupgen_save_masks(cpu);
_wakeupgen_set_all(cpu, WKG_MASK_ALL);
} else {
_wakeupgen_set_all(cpu, WKG_UNMASK_ALL);
_wakeupgen_restore_masks(cpu);
}
raw_spin_unlock_irqrestore(&wakeupgen_lock, flags);
}
#endif
#ifdef CONFIG_CPU_PM
static inline void omap4_irq_save_context(void)
{
u32 i, val;
if (omap_rev() == OMAP4430_REV_ES1_0)
return;
for (i = 0; i < irq_banks; i++) {
/* Save the CPUx interrupt mask for IRQ 0 to 127 */
val = wakeupgen_readl(i, 0);
sar_writel(val, WAKEUPGENENB_OFFSET_CPU0, i);
val = wakeupgen_readl(i, 1);
sar_writel(val, WAKEUPGENENB_OFFSET_CPU1, i);
/*
* Disable the secure interrupts for CPUx. The restore
* code blindly restores secure and non-secure interrupt
* masks from SAR RAM. Secure interrupts are not suppose
* to be enabled from HLOS. So overwrite the SAR location
* so that the secure interrupt remains disabled.
*/
sar_writel(0x0, WAKEUPGENENB_SECURE_OFFSET_CPU0, i);
sar_writel(0x0, WAKEUPGENENB_SECURE_OFFSET_CPU1, i);
}
/* Save AuxBoot* registers */
val = readl_relaxed(wakeupgen_base + OMAP_AUX_CORE_BOOT_0);
writel_relaxed(val, sar_base + AUXCOREBOOT0_OFFSET);
val = readl_relaxed(wakeupgen_base + OMAP_AUX_CORE_BOOT_1);
writel_relaxed(val, sar_base + AUXCOREBOOT1_OFFSET);
/* Save SyncReq generation logic */
val = readl_relaxed(wakeupgen_base + OMAP_PTMSYNCREQ_MASK);
writel_relaxed(val, sar_base + PTMSYNCREQ_MASK_OFFSET);
val = readl_relaxed(wakeupgen_base + OMAP_PTMSYNCREQ_EN);
writel_relaxed(val, sar_base + PTMSYNCREQ_EN_OFFSET);
/* Set the Backup Bit Mask status */
val = readl_relaxed(sar_base + SAR_BACKUP_STATUS_OFFSET);
val |= SAR_BACKUP_STATUS_WAKEUPGEN;
writel_relaxed(val, sar_base + SAR_BACKUP_STATUS_OFFSET);
}
static inline void omap5_irq_save_context(void)
{
u32 i, val;
for (i = 0; i < irq_banks; i++) {
/* Save the CPUx interrupt mask for IRQ 0 to 159 */
val = wakeupgen_readl(i, 0);
sar_writel(val, OMAP5_WAKEUPGENENB_OFFSET_CPU0, i);
val = wakeupgen_readl(i, 1);
sar_writel(val, OMAP5_WAKEUPGENENB_OFFSET_CPU1, i);
sar_writel(0x0, OMAP5_WAKEUPGENENB_SECURE_OFFSET_CPU0, i);
sar_writel(0x0, OMAP5_WAKEUPGENENB_SECURE_OFFSET_CPU1, i);
}
/* Save AuxBoot* registers */
val = readl_relaxed(wakeupgen_base + OMAP_AUX_CORE_BOOT_0);
writel_relaxed(val, sar_base + OMAP5_AUXCOREBOOT0_OFFSET);
val = readl_relaxed(wakeupgen_base + OMAP_AUX_CORE_BOOT_0);
writel_relaxed(val, sar_base + OMAP5_AUXCOREBOOT1_OFFSET);
/* Set the Backup Bit Mask status */
val = readl_relaxed(sar_base + OMAP5_SAR_BACKUP_STATUS_OFFSET);
val |= SAR_BACKUP_STATUS_WAKEUPGEN;
writel_relaxed(val, sar_base + OMAP5_SAR_BACKUP_STATUS_OFFSET);
}
/*
* Save WakeupGen interrupt context in SAR BANK3. Restore is done by
* ROM code. WakeupGen IP is integrated along with GIC to manage the
* interrupt wakeups from CPU low power states. It manages
* masking/unmasking of Shared peripheral interrupts(SPI). So the
* interrupt enable/disable control should be in sync and consistent
* at WakeupGen and GIC so that interrupts are not lost.
*/
static void irq_save_context(void)
{
if (!sar_base)
sar_base = omap4_get_sar_ram_base();
if (soc_is_omap54xx())
omap5_irq_save_context();
else
omap4_irq_save_context();
}
/*
* Clear WakeupGen SAR backup status.
*/
static void irq_sar_clear(void)
{
u32 val;
u32 offset = SAR_BACKUP_STATUS_OFFSET;
if (soc_is_omap54xx())
offset = OMAP5_SAR_BACKUP_STATUS_OFFSET;
val = readl_relaxed(sar_base + offset);
val &= ~SAR_BACKUP_STATUS_WAKEUPGEN;
writel_relaxed(val, sar_base + offset);
}
/*
* Save GIC and Wakeupgen interrupt context using secure API
* for HS/EMU devices.
*/
static void irq_save_secure_context(void)
{
u32 ret;
ret = omap_secure_dispatcher(OMAP4_HAL_SAVEGIC_INDEX,
FLAG_START_CRITICAL,
0, 0, 0, 0, 0);
if (ret != API_HAL_RET_VALUE_OK)
pr_err("GIC and Wakeupgen context save failed\n");
}
#endif
#ifdef CONFIG_HOTPLUG_CPU
static int irq_cpu_hotplug_notify(struct notifier_block *self,
unsigned long action, void *hcpu)
{
unsigned int cpu = (unsigned int)hcpu;
switch (action) {
case CPU_ONLINE:
wakeupgen_irqmask_all(cpu, 0);
break;
case CPU_DEAD:
wakeupgen_irqmask_all(cpu, 1);
break;
}
return NOTIFY_OK;
}
static struct notifier_block __refdata irq_hotplug_notifier = {
.notifier_call = irq_cpu_hotplug_notify,
};
static void __init irq_hotplug_init(void)
{
register_hotcpu_notifier(&irq_hotplug_notifier);
}
#else
static void __init irq_hotplug_init(void)
{}
#endif
#ifdef CONFIG_CPU_PM
static int irq_notifier(struct notifier_block *self, unsigned long cmd, void *v)
{
switch (cmd) {
case CPU_CLUSTER_PM_ENTER:
if (omap_type() == OMAP2_DEVICE_TYPE_GP)
irq_save_context();
else
irq_save_secure_context();
break;
case CPU_CLUSTER_PM_EXIT:
if (omap_type() == OMAP2_DEVICE_TYPE_GP)
irq_sar_clear();
break;
}
return NOTIFY_OK;
}
static struct notifier_block irq_notifier_block = {
.notifier_call = irq_notifier,
};
static void __init irq_pm_init(void)
{
/* FIXME: Remove this when MPU OSWR support is added */
if (!IS_PM44XX_ERRATUM(PM_OMAP4_CPU_OSWR_DISABLE))
cpu_pm_register_notifier(&irq_notifier_block);
}
#else
static void __init irq_pm_init(void)
{}
#endif
void __iomem *omap_get_wakeupgen_base(void)
{
return wakeupgen_base;
}
int omap_secure_apis_support(void)
{
return omap_secure_apis;
}
/*
* Initialise the wakeupgen module.
*/
int __init omap_wakeupgen_init(void)
{
int i;
unsigned int boot_cpu = smp_processor_id();
u32 val;
/* Not supported on OMAP4 ES1.0 silicon */
if (omap_rev() == OMAP4430_REV_ES1_0) {
WARN(1, "WakeupGen: Not supported on OMAP4430 ES1.0\n");
return -EPERM;
}
/* Static mapping, never released */
wakeupgen_base = ioremap(OMAP_WKUPGEN_BASE, SZ_4K);
if (WARN_ON(!wakeupgen_base))
return -ENOMEM;
if (cpu_is_omap44xx()) {
irq_banks = OMAP4_NR_BANKS;
max_irqs = OMAP4_NR_IRQS;
omap_secure_apis = 1;
} else if (soc_is_am43xx()) {
irq_banks = AM43XX_NR_REG_BANKS;
max_irqs = AM43XX_IRQS;
}
/* Clear all IRQ bitmasks at wakeupGen level */
for (i = 0; i < irq_banks; i++) {
wakeupgen_writel(0, i, CPU0_ID);
if (!soc_is_am43xx())
wakeupgen_writel(0, i, CPU1_ID);
}
/*
* Override GIC architecture specific functions to add
* OMAP WakeupGen interrupt controller along with GIC
*/
gic_arch_extn.irq_mask = wakeupgen_mask;
gic_arch_extn.irq_unmask = wakeupgen_unmask;
gic_arch_extn.flags = IRQCHIP_MASK_ON_SUSPEND | IRQCHIP_SKIP_SET_WAKE;
/*
* FIXME: Add support to set_smp_affinity() once the core
* GIC code has necessary hooks in place.
*/
/* Associate all the IRQs to boot CPU like GIC init does. */
for (i = 0; i < max_irqs; i++)
irq_target_cpu[i] = boot_cpu;
/*
* Enables OMAP5 ES2 PM Mode using ES2_PM_MODE in AMBA_IF_MODE
* 0x0: ES1 behavior, CPU cores would enter and exit OFF mode together.
* 0x1: ES2 behavior, CPU cores are allowed to enter/exit OFF mode
* independently.
* This needs to be set one time thanks to always ON domain.
*
* We do not support ES1 behavior anymore. OMAP5 is assumed to be
* ES2.0, and the same is applicable for DRA7.
*/
if (soc_is_omap54xx() || soc_is_dra7xx()) {
val = __raw_readl(wakeupgen_base + OMAP_AMBA_IF_MODE);
val |= BIT(5);
omap_smc1(OMAP5_MON_AMBA_IF_INDEX, val);
}
irq_hotplug_init();
irq_pm_init();
return 0;
}