kernel-ark/arch/arm/mach-imx/gpc.c
Lucas Stach d438462c20 ARM: imx6: gpc: always enable PU domain if CONFIG_PM is not set
If CONFIG_PM is not set the PU power domain needs to be enabled always,
otherwise there are two failure scenarios which will hang the system if
one of the devices in the PU domain is accessed.

1. New DTs (4.1+) drop the "always-on" property from the PU regulator, so
if it isn't properly enabled by the GPC code it will be disabled at the
end of boot.

2. If the bootloader already disabled the PU domain the GPC explicitly
needs to enable it again, even if the kernel doesn't do any power
management. This is a bit hypothetical, as it requires to boot a
mainline kernel on a downstream bootloader, as no mainline bootloader
disables the PM domains.

Cc: <stable@vger.kernel.org> # 4.1
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
2015-07-08 22:52:08 +08:00

472 lines
11 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/clk.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/platform_device.h>
#include <linux/pm_domain.h>
#include <linux/regulator/consumer.h>
#include <linux/irqchip/arm-gic.h>
#include "common.h"
#include "hardware.h"
#define GPC_CNTR 0x000
#define GPC_IMR1 0x008
#define GPC_PGC_GPU_PDN 0x260
#define GPC_PGC_GPU_PUPSCR 0x264
#define GPC_PGC_GPU_PDNSCR 0x268
#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
#define GPC_MAX_IRQS (IMR_NUM * 32)
#define GPU_VPU_PUP_REQ BIT(1)
#define GPU_VPU_PDN_REQ BIT(0)
#define GPC_CLK_MAX 6
struct pu_domain {
struct generic_pm_domain base;
struct regulator *reg;
struct clk *clk[GPC_CLK_MAX];
int num_clks;
};
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;
u32 mask;
mask = 1 << d->hwirq % 32;
gpc_wake_irqs[idx] = on ? gpc_wake_irqs[idx] | mask :
gpc_wake_irqs[idx] & ~mask;
/*
* Do *not* call into the parent, as the GIC doesn't have any
* wake-up facility...
*/
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 * 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 * 4;
val = readl_relaxed(reg);
val |= 1 << (hwirq % 32);
writel_relaxed(val, reg);
}
static void imx_gpc_irq_unmask(struct irq_data *d)
{
imx_gpc_hwirq_unmask(d->hwirq);
irq_chip_unmask_parent(d);
}
static void imx_gpc_irq_mask(struct irq_data *d)
{
imx_gpc_hwirq_mask(d->hwirq);
irq_chip_mask_parent(d);
}
static struct irq_chip imx_gpc_chip = {
.name = "GPC",
.irq_eoi = irq_chip_eoi_parent,
.irq_mask = imx_gpc_irq_mask,
.irq_unmask = imx_gpc_irq_unmask,
.irq_retrigger = irq_chip_retrigger_hierarchy,
.irq_set_wake = imx_gpc_irq_set_wake,
#ifdef CONFIG_SMP
.irq_set_affinity = irq_chip_set_affinity_parent,
#endif
};
static int imx_gpc_domain_xlate(struct irq_domain *domain,
struct device_node *controller,
const u32 *intspec,
unsigned int intsize,
unsigned long *out_hwirq,
unsigned int *out_type)
{
if (domain->of_node != controller)
return -EINVAL; /* Shouldn't happen, really... */
if (intsize != 3)
return -EINVAL; /* Not GIC compliant */
if (intspec[0] != 0)
return -EINVAL; /* No PPI should point to this domain */
*out_hwirq = intspec[1];
*out_type = intspec[2];
return 0;
}
static int imx_gpc_domain_alloc(struct irq_domain *domain,
unsigned int irq,
unsigned int nr_irqs, void *data)
{
struct of_phandle_args *args = data;
struct of_phandle_args parent_args;
irq_hw_number_t hwirq;
int i;
if (args->args_count != 3)
return -EINVAL; /* Not GIC compliant */
if (args->args[0] != 0)
return -EINVAL; /* No PPI should point to this domain */
hwirq = args->args[1];
if (hwirq >= GPC_MAX_IRQS)
return -EINVAL; /* Can't deal with this */
for (i = 0; i < nr_irqs; i++)
irq_domain_set_hwirq_and_chip(domain, irq + i, hwirq + i,
&imx_gpc_chip, NULL);
parent_args = *args;
parent_args.np = domain->parent->of_node;
return irq_domain_alloc_irqs_parent(domain, irq, nr_irqs, &parent_args);
}
static const struct irq_domain_ops imx_gpc_domain_ops = {
.xlate = imx_gpc_domain_xlate,
.alloc = imx_gpc_domain_alloc,
.free = irq_domain_free_irqs_common,
};
static int __init imx_gpc_init(struct device_node *node,
struct device_node *parent)
{
struct irq_domain *parent_domain, *domain;
int i;
if (!parent) {
pr_err("%s: no parent, giving up\n", node->full_name);
return -ENODEV;
}
parent_domain = irq_find_host(parent);
if (!parent_domain) {
pr_err("%s: unable to obtain parent domain\n", node->full_name);
return -ENXIO;
}
gpc_base = of_iomap(node, 0);
if (WARN_ON(!gpc_base))
return -ENOMEM;
domain = irq_domain_add_hierarchy(parent_domain, 0, GPC_MAX_IRQS,
node, &imx_gpc_domain_ops,
NULL);
if (!domain) {
iounmap(gpc_base);
return -ENOMEM;
}
/* Initially mask all interrupts */
for (i = 0; i < IMR_NUM; i++)
writel_relaxed(~0, gpc_base + GPC_IMR1 + i * 4);
return 0;
}
/*
* We cannot use the IRQCHIP_DECLARE macro that lives in
* drivers/irqchip, so we're forced to roll our own. Not very nice.
*/
OF_DECLARE_2(irqchip, imx_gpc, "fsl,imx6q-gpc", imx_gpc_init);
void __init imx_gpc_check_dt(void)
{
struct device_node *np;
np = of_find_compatible_node(NULL, NULL, "fsl,imx6q-gpc");
if (WARN_ON(!np))
return;
if (WARN_ON(!of_find_property(np, "interrupt-controller", NULL))) {
pr_warn("Outdated DT detected, suspend/resume will NOT work\n");
/* map GPC, so that at least CPUidle and WARs keep working */
gpc_base = of_iomap(np, 0);
}
}
static void _imx6q_pm_pu_power_off(struct generic_pm_domain *genpd)
{
int iso, iso2sw;
u32 val;
/* Read ISO and ISO2SW power down delays */
val = readl_relaxed(gpc_base + GPC_PGC_GPU_PDNSCR);
iso = val & 0x3f;
iso2sw = (val >> 8) & 0x3f;
/* Gate off PU domain when GPU/VPU when powered down */
writel_relaxed(0x1, gpc_base + GPC_PGC_GPU_PDN);
/* Request GPC to power down GPU/VPU */
val = readl_relaxed(gpc_base + GPC_CNTR);
val |= GPU_VPU_PDN_REQ;
writel_relaxed(val, gpc_base + GPC_CNTR);
/* Wait ISO + ISO2SW IPG clock cycles */
ndelay((iso + iso2sw) * 1000 / 66);
}
static int imx6q_pm_pu_power_off(struct generic_pm_domain *genpd)
{
struct pu_domain *pu = container_of(genpd, struct pu_domain, base);
_imx6q_pm_pu_power_off(genpd);
if (pu->reg)
regulator_disable(pu->reg);
return 0;
}
static int imx6q_pm_pu_power_on(struct generic_pm_domain *genpd)
{
struct pu_domain *pu = container_of(genpd, struct pu_domain, base);
int i, ret, sw, sw2iso;
u32 val;
if (pu->reg)
ret = regulator_enable(pu->reg);
if (pu->reg && ret) {
pr_err("%s: failed to enable regulator: %d\n", __func__, ret);
return ret;
}
/* Enable reset clocks for all devices in the PU domain */
for (i = 0; i < pu->num_clks; i++)
clk_prepare_enable(pu->clk[i]);
/* Gate off PU domain when GPU/VPU when powered down */
writel_relaxed(0x1, gpc_base + GPC_PGC_GPU_PDN);
/* Read ISO and ISO2SW power down delays */
val = readl_relaxed(gpc_base + GPC_PGC_GPU_PUPSCR);
sw = val & 0x3f;
sw2iso = (val >> 8) & 0x3f;
/* Request GPC to power up GPU/VPU */
val = readl_relaxed(gpc_base + GPC_CNTR);
val |= GPU_VPU_PUP_REQ;
writel_relaxed(val, gpc_base + GPC_CNTR);
/* Wait ISO + ISO2SW IPG clock cycles */
ndelay((sw + sw2iso) * 1000 / 66);
/* Disable reset clocks for all devices in the PU domain */
for (i = 0; i < pu->num_clks; i++)
clk_disable_unprepare(pu->clk[i]);
return 0;
}
static struct generic_pm_domain imx6q_arm_domain = {
.name = "ARM",
};
static struct pu_domain imx6q_pu_domain = {
.base = {
.name = "PU",
.power_off = imx6q_pm_pu_power_off,
.power_on = imx6q_pm_pu_power_on,
.power_off_latency_ns = 25000,
.power_on_latency_ns = 2000000,
},
};
static struct generic_pm_domain imx6sl_display_domain = {
.name = "DISPLAY",
};
static struct generic_pm_domain *imx_gpc_domains[] = {
&imx6q_arm_domain,
&imx6q_pu_domain.base,
&imx6sl_display_domain,
};
static struct genpd_onecell_data imx_gpc_onecell_data = {
.domains = imx_gpc_domains,
.num_domains = ARRAY_SIZE(imx_gpc_domains),
};
static int imx_gpc_genpd_init(struct device *dev, struct regulator *pu_reg)
{
struct clk *clk;
int i;
imx6q_pu_domain.reg = pu_reg;
for (i = 0; ; i++) {
clk = of_clk_get(dev->of_node, i);
if (IS_ERR(clk))
break;
if (i >= GPC_CLK_MAX) {
dev_err(dev, "more than %d clocks\n", GPC_CLK_MAX);
goto clk_err;
}
imx6q_pu_domain.clk[i] = clk;
}
imx6q_pu_domain.num_clks = i;
/* Enable power always in case bootloader disabled it. */
imx6q_pm_pu_power_on(&imx6q_pu_domain.base);
if (!IS_ENABLED(CONFIG_PM_GENERIC_DOMAINS))
return 0;
pm_genpd_init(&imx6q_pu_domain.base, NULL, false);
return of_genpd_add_provider_onecell(dev->of_node,
&imx_gpc_onecell_data);
clk_err:
while (i--)
clk_put(imx6q_pu_domain.clk[i]);
return -EINVAL;
}
static int imx_gpc_probe(struct platform_device *pdev)
{
struct regulator *pu_reg;
int ret;
/* bail out if DT too old and doesn't provide the necessary info */
if (!of_property_read_bool(pdev->dev.of_node, "#power-domain-cells"))
return 0;
pu_reg = devm_regulator_get_optional(&pdev->dev, "pu");
if (PTR_ERR(pu_reg) == -ENODEV)
pu_reg = NULL;
if (IS_ERR(pu_reg)) {
ret = PTR_ERR(pu_reg);
dev_err(&pdev->dev, "failed to get pu regulator: %d\n", ret);
return ret;
}
return imx_gpc_genpd_init(&pdev->dev, pu_reg);
}
static const struct of_device_id imx_gpc_dt_ids[] = {
{ .compatible = "fsl,imx6q-gpc" },
{ .compatible = "fsl,imx6sl-gpc" },
{ }
};
static struct platform_driver imx_gpc_driver = {
.driver = {
.name = "imx-gpc",
.of_match_table = imx_gpc_dt_ids,
},
.probe = imx_gpc_probe,
};
static int __init imx_pgc_init(void)
{
return platform_driver_register(&imx_gpc_driver);
}
subsys_initcall(imx_pgc_init);