[PATCH v5 1/3] power-domain: add power domain drivers for Rockchip platform
Dmitry Torokhov
dmitry.torokhov at gmail.com
Tue Oct 21 12:58:54 PDT 2014
Hi Jinkun,
On Tue, Oct 21, 2014 at 02:13:26AM -0700, jinkun.hong wrote:
> From: "jinkun.hong" <jinkun.hong at rock-chips.com>
>
> Add power domain drivers based on generic power domain for Rockchip platform,
> and support RK3288.
>
> Signed-off-by: Jack Dai <jack.dai at rock-chips.com>
> Signed-off-by: jinkun.hong <jinkun.hong at rock-chips.com>
>
> ---
>
> Changes in v5:
> - delete idle_lock
> - add timeout in rockchip_pmu_set_idle_request()
>
> Changes in v4:
> - use list storage dev
>
> Changes in v3:
> - change use pm_clk_resume() and pm_clk_suspend()
>
> Changes in v2:
> - remove the "pd->pd.of_node = np"
>
> arch/arm/mach-rockchip/Kconfig | 1 +
> arch/arm/mach-rockchip/Makefile | 1 +
> arch/arm/mach-rockchip/pm_domains.c | 368 +++++++++++++++++++++++++++++++++++
> 3 files changed, 370 insertions(+)
> create mode 100644 arch/arm/mach-rockchip/pm_domains.c
>
> diff --git a/arch/arm/mach-rockchip/Kconfig b/arch/arm/mach-rockchip/Kconfig
> index d168669..4920a88 100644
> --- a/arch/arm/mach-rockchip/Kconfig
> +++ b/arch/arm/mach-rockchip/Kconfig
> @@ -12,6 +12,7 @@ config ARCH_ROCKCHIP
> select DW_APB_TIMER_OF
> select ARM_GLOBAL_TIMER
> select CLKSRC_ARM_GLOBAL_TIMER_SCHED_CLOCK
> + select PM_GENERIC_DOMAINS if PM
> help
> Support for Rockchip's Cortex-A9 Single-to-Quad-Core-SoCs
> containing the RK2928, RK30xx and RK31xx series.
> diff --git a/arch/arm/mach-rockchip/Makefile b/arch/arm/mach-rockchip/Makefile
> index b29d8ea..805268d 100644
> --- a/arch/arm/mach-rockchip/Makefile
> +++ b/arch/arm/mach-rockchip/Makefile
> @@ -2,3 +2,4 @@ CFLAGS_platsmp.o := -march=armv7-a
>
> obj-$(CONFIG_ARCH_ROCKCHIP) += rockchip.o
> obj-$(CONFIG_SMP) += headsmp.o platsmp.o
> +obj-$(CONFIG_PM_GENERIC_DOMAINS) += pm_domains.o
> diff --git a/arch/arm/mach-rockchip/pm_domains.c b/arch/arm/mach-rockchip/pm_domains.c
> new file mode 100644
> index 0000000..8f13445
> --- /dev/null
> +++ b/arch/arm/mach-rockchip/pm_domains.c
> @@ -0,0 +1,368 @@
> +/*
> + * Rockchip Generic power domain support.
> + *
> + * Copyright (c) 2014 ROCKCHIP, Co. Ltd.
> + * Author: Hong Jinkun <jinkun.hong at rock-chips.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/module.h>
> +#include <linux/io.h>
> +#include <linux/err.h>
> +#include <linux/slab.h>
> +#include <linux/pm_domain.h>
> +#include <linux/of_address.h>
> +#include <linux/of_platform.h>
> +#include <linux/sched.h>
> +#include <linux/clk.h>
> +#include <linux/regmap.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/spinlock.h>
> +#include <linux/pm_clock.h>
> +#include <linux/delay.h>
> +
> +#define PWR_OFFSET 0x08
> +#define STATUS_OFFSET 0x0c
> +#define REQ_OFFSET 0x10
> +#define IDLE_OFFSET 0x14
> +#define ACK_OFFSET 0x14
> +
> +struct rockchip_dev_entry {
> + struct list_head node;
> + struct device *dev;
> +};
> +
> +struct rockchip_domain {
> + struct generic_pm_domain base;
> + struct device *dev;
> + struct regmap *regmap_pmu;
> + struct list_head dev_list;
> + /* spin lock for read/write pmu reg */
> + spinlock_t pmu_lock;
> + /* spin lock for dev_list */
> + spinlock_t dev_lock;
> + u32 pwr_shift;
> + u32 status_shift;
> + u32 req_shift;
> + u32 idle_shift;
> + u32 ack_shift;
> +};
> +
> +#define to_rockchip_pd(_gpd) container_of(_gpd, struct rockchip_domain, base)
> +
> +static int rockchip_pmu_set_idle_request(struct rockchip_domain *pd,
> + bool idle)
> +{
> + u32 idle_mask = BIT(pd->idle_shift);
> + u32 idle_target = idle << (pd->idle_shift);
> + u32 ack_mask = BIT(pd->ack_shift);
> + u32 ack_target = idle << (pd->ack_shift);
> + unsigned int mask = BIT(pd->req_shift);
> + unsigned int val;
> + unsigned long flags;
> + int timeout = 0;
> +
> + val = (idle) ? mask : 0;
> + regmap_update_bits(pd->regmap_pmu, REQ_OFFSET, mask, val);
> + dsb();
> +
> + do {
> + regmap_read(pd->regmap_pmu, ACK_OFFSET, &val);
> + udelay(1);
> + if (timeout > 10) {
> + pr_err("%s wait pmu ack timeout!\n", __func__);
> + break;
> + }
> + timeout += 1;
> + } while ((val & ack_mask) != ack_target);
> +
> + timeout = 0;
> + do {
> + regmap_read(pd->regmap_pmu, IDLE_OFFSET, &val);
> + udelay(1);
> + if (timeout > 10) {
> + pr_err("%s wait pmu idle timeout!\n", __func__);
> + break;
> + }
> + timeout += 1;
> + } while ((val & idle_mask) != idle_target);
> + return 0;
> +}
> +
> +static bool rockchip_pmu_power_domain_is_on(struct rockchip_domain *pd)
> +{
> + unsigned int val;
> +
> + regmap_read(pd->regmap_pmu, STATUS_OFFSET, &val);
> +
> + /* 1'b0: power on, 1'b1: power off */
> + return !(val & BIT(pd->status_shift));
> +}
> +
> +static void rockchip_do_pmu_set_power_domain(
> + struct rockchip_domain *pd, bool on)
> +{
> + unsigned int mask = BIT(pd->pwr_shift);
> + unsigned int val;
> +
> + val = (on) ? 0 : mask;
> + regmap_update_bits(pd->regmap_pmu, PWR_OFFSET, mask, val);
> + dsb();
> +
> + do {
> + regmap_read(pd->regmap_pmu, STATUS_OFFSET, &val);
> + } while ((val & BIT(pd->status_shift)) == on);
> +}
> +
> +static int rockchip_pmu_set_power_domain(struct rockchip_domain *pd,
> + bool on)
> +{
> + unsigned long flags;
> +
> + spin_lock_irqsave(&pd->pmu_lock, flags);
You only call rockchip_pmu_set_power_domain() with pd->dev_lock held,
why do you need this spinlock?
> + if (rockchip_pmu_power_domain_is_on(pd) == on)
> + goto out;
> +
> + if (!on) {
> + /* FIXME: add code to save AXI_QOS */
> + /* if power down, idle request to NIU first */
> + rockchip_pmu_set_idle_request(pd, true);
> + }
> +
> + rockchip_do_pmu_set_power_domain(pd, on);
> +
> + if (on) {
> + /* if power up, idle request release to NIU */
> + rockchip_pmu_set_idle_request(pd, false);
> + /* FIXME: add code to restore AXI_QOS */
> + }
> +out:
> + spin_unlock_irqrestore(&pd->pmu_lock, flags);
> + return 0;
> +}
> +
> +static int rockchip_pd_power(struct rockchip_domain *pd, bool power_on)
> +{
> + int i = 0;
> + int ret = 0;
> + struct rockchip_dev_entry *de;
> +
> + spin_lock_irq(&pd->dev_lock);
Do you really need to run here with interrupts off? Maybe a mutex would
be better here?
> +
> + list_for_each_entry(de, &pd->dev_list, node) {
> + i += 1;
> + pm_clk_resume(pd->dev);
Do you really need to call pm_clk_resume() number of times that there
are devices in power domain? Did you want it to be
pm_clk_resume(de->dev);
by any chance?
> + }
> +
> + /* no clk, set power domain will fail */
> + if (i == 0) {
> + pr_err("%s: failed to on/off power domain!", __func__);
> + spin_unlock_irq(&pd->dev_lock);
> + return ret;
> + }
Instead of counting I'd do
if (list_empty(&pd->dev_list)) {
pr_waen("%s: no devices in power domain\n", __func__);
goto out;
}
in the beginning of the function.
> +
> + ret = rockchip_pmu_set_power_domain(pd, power_on);
> +
> + list_for_each_entry(de, &pd->dev_list, node) {
> + pm_clk_suspend(pd->dev);
Same here?
> + }
> +
> + spin_unlock_irq(&pd->dev_lock);
> +
> + return ret;
> +}
> +
> +static int rockchip_pd_power_on(struct generic_pm_domain *domain)
> +{
> + struct rockchip_domain *pd = to_rockchip_pd(domain);
> +
> + return rockchip_pd_power(pd, true);
> +}
> +
> +static int rockchip_pd_power_off(struct generic_pm_domain *domain)
> +{
> + struct rockchip_domain *pd = to_rockchip_pd(domain);
> +
> + return rockchip_pd_power(pd, false);
> +}
> +
> +void rockchip_pm_domain_attach_dev(struct device *dev)
> +{
> + int ret;
> + int i = 0;
> + struct clk *clk;
> + struct rockchip_domain *pd;
> + struct rockchip_dev_entry *de;
> +
> + pd = (struct rockchip_domain *)dev->pm_domain;
> + ret = pm_clk_create(dev);
> + if (ret) {
> + dev_err(dev, "pm_clk_create failed %d\n", ret);
> + return;
> + };
Stray semicolon.
> +
> + while ((clk = of_clk_get(dev->of_node, i++)) && !IS_ERR(clk)) {
> + ret = pm_clk_add_clk(dev, clk);
> + if (ret) {
> + dev_err(dev, "pm_clk_add_clk failed %d\n", ret);
> + goto clk_err;
> + };
> + }
> +
> + de = devm_kcalloc(pd->dev, 1,
> + sizeof(struct rockchip_dev_entry *), GFP_KERNEL);
Why devm_calloc for a single element and not devm_kzalloc? Also, I am a
bit concerned about using devm_* API here. They are better reserved fir
driver's ->probe() paths whereas we are called from
dev_pm_domain_attach() which is more general API (yes, currently it is
used by buses probing code, but that might change in the future).
Also, where is OOM error handling?
> + spin_lock_irq(&pd->dev_lock);
> + list_add_tail(&de->node, &pd->dev_list);
> + spin_unlock_irq(&pd->dev_lock);
> +
> + return;
> +clk_err:
> + pm_clk_destroy(dev);
> +}
> +
> +void rockchip_pm_domain_detach_dev(struct device *dev)
> +{
> + struct rockchip_domain *pd;
> + struct rockchip_dev_entry *de;
> +
> + pd = (struct rockchip_domain *)dev->pm_domain;
> + spin_lock_irq(&pd->dev_lock);
> +
> + list_for_each_entry(de, &pd->dev_list, node) {
> + if (de->dev == dev)
> + goto remove;
If you use mutex instead of spinlock I think you'll be able to do
list_del/pm_clk_destroy() right here. I'd free memory here as well.
Thanks.
--
Dmitry
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