linux/arch/arm/mach-imx/gpc.c
Anson Huang 05136f0897 ARM: imx: support arm power off in cpuidle for i.mx6sx
This patch introduces an independent cpuidle driver for
i.MX6SX, and supports arm power off in idle, totally
3 levels of cpuidle are supported as below:

1. ARM WFI;
2. SOC in WAIT mode;
3. SOC in WAIT mode + ARM power off.

ARM power off can save at least 5mW power.

This patch also replaces imx6q_enable_rbc with imx6_enable_rbc.

Signed-off-by: Anson Huang <b20788@freescale.com>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
2015-01-05 21:34:29 +08:00

173 lines
3.8 KiB
C

/*
* Copyright 2011-2013 Freescale Semiconductor, Inc.
* Copyright 2011 Linaro Ltd.
*
* The code contained herein is licensed under the GNU General Public
* License. You may obtain a copy of the GNU General Public License
* Version 2 or later at the following locations:
*
* http://www.opensource.org/licenses/gpl-license.html
* http://www.gnu.org/copyleft/gpl.html
*/
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/irqchip/arm-gic.h>
#include "common.h"
#define GPC_IMR1 0x008
#define GPC_PGC_CPU_PDN 0x2a0
#define GPC_PGC_CPU_PUPSCR 0x2a4
#define GPC_PGC_CPU_PDNSCR 0x2a8
#define GPC_PGC_SW2ISO_SHIFT 0x8
#define GPC_PGC_SW_SHIFT 0x0
#define IMR_NUM 4
static void __iomem *gpc_base;
static u32 gpc_wake_irqs[IMR_NUM];
static u32 gpc_saved_imrs[IMR_NUM];
void imx_gpc_set_arm_power_up_timing(u32 sw2iso, u32 sw)
{
writel_relaxed((sw2iso << GPC_PGC_SW2ISO_SHIFT) |
(sw << GPC_PGC_SW_SHIFT), gpc_base + GPC_PGC_CPU_PUPSCR);
}
void imx_gpc_set_arm_power_down_timing(u32 sw2iso, u32 sw)
{
writel_relaxed((sw2iso << GPC_PGC_SW2ISO_SHIFT) |
(sw << GPC_PGC_SW_SHIFT), gpc_base + GPC_PGC_CPU_PDNSCR);
}
void imx_gpc_set_arm_power_in_lpm(bool power_off)
{
writel_relaxed(power_off, gpc_base + GPC_PGC_CPU_PDN);
}
void imx_gpc_pre_suspend(bool arm_power_off)
{
void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
int i;
/* Tell GPC to power off ARM core when suspend */
if (arm_power_off)
imx_gpc_set_arm_power_in_lpm(arm_power_off);
for (i = 0; i < IMR_NUM; i++) {
gpc_saved_imrs[i] = readl_relaxed(reg_imr1 + i * 4);
writel_relaxed(~gpc_wake_irqs[i], reg_imr1 + i * 4);
}
}
void imx_gpc_post_resume(void)
{
void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
int i;
/* Keep ARM core powered on for other low-power modes */
imx_gpc_set_arm_power_in_lpm(false);
for (i = 0; i < IMR_NUM; i++)
writel_relaxed(gpc_saved_imrs[i], reg_imr1 + i * 4);
}
static int imx_gpc_irq_set_wake(struct irq_data *d, unsigned int on)
{
unsigned int idx = d->hwirq / 32 - 1;
u32 mask;
/* Sanity check for SPI irq */
if (d->hwirq < 32)
return -EINVAL;
mask = 1 << d->hwirq % 32;
gpc_wake_irqs[idx] = on ? gpc_wake_irqs[idx] | mask :
gpc_wake_irqs[idx] & ~mask;
return 0;
}
void imx_gpc_mask_all(void)
{
void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
int i;
for (i = 0; i < IMR_NUM; i++) {
gpc_saved_imrs[i] = readl_relaxed(reg_imr1 + i * 4);
writel_relaxed(~0, reg_imr1 + i * 4);
}
}
void imx_gpc_restore_all(void)
{
void __iomem *reg_imr1 = gpc_base + GPC_IMR1;
int i;
for (i = 0; i < IMR_NUM; i++)
writel_relaxed(gpc_saved_imrs[i], reg_imr1 + i * 4);
}
void imx_gpc_hwirq_unmask(unsigned int hwirq)
{
void __iomem *reg;
u32 val;
reg = gpc_base + GPC_IMR1 + (hwirq / 32 - 1) * 4;
val = readl_relaxed(reg);
val &= ~(1 << hwirq % 32);
writel_relaxed(val, reg);
}
void imx_gpc_hwirq_mask(unsigned int hwirq)
{
void __iomem *reg;
u32 val;
reg = gpc_base + GPC_IMR1 + (hwirq / 32 - 1) * 4;
val = readl_relaxed(reg);
val |= 1 << (hwirq % 32);
writel_relaxed(val, reg);
}
static void imx_gpc_irq_unmask(struct irq_data *d)
{
/* Sanity check for SPI irq */
if (d->hwirq < 32)
return;
imx_gpc_hwirq_unmask(d->hwirq);
}
static void imx_gpc_irq_mask(struct irq_data *d)
{
/* Sanity check for SPI irq */
if (d->hwirq < 32)
return;
imx_gpc_hwirq_mask(d->hwirq);
}
void __init imx_gpc_init(void)
{
struct device_node *np;
int i;
np = of_find_compatible_node(NULL, NULL, "fsl,imx6q-gpc");
gpc_base = of_iomap(np, 0);
WARN_ON(!gpc_base);
/* Initially mask all interrupts */
for (i = 0; i < IMR_NUM; i++)
writel_relaxed(~0, gpc_base + GPC_IMR1 + i * 4);
/* Register GPC as the secondary interrupt controller behind GIC */
gic_arch_extn.irq_mask = imx_gpc_irq_mask;
gic_arch_extn.irq_unmask = imx_gpc_irq_unmask;
gic_arch_extn.irq_set_wake = imx_gpc_irq_set_wake;
}