[PATCH v11 2/3] power-domain: rockchip: add power doamin driver

Caesar Wang caesar.wang at rock-chips.com
Sun Nov 16 19:53:37 PST 2014


在 2014年11月14日 03:35, Daniel Kurtz 写道:
> On Thu, Nov 13, 2014 at 6:01 AM, Caesar Wang <caesar.wang at rock-chips.com> wrote:
>> In order to meet high performance and low power requirements, a power
>> management unit is designed or saving power when RK3288 in low power mode.
>> The RK3288 PMU is dedicated for managing the power ot the whole chip.
>>
>> Signed-off-by: Jack Dai <jack.dai at rock-chips.com>
>> Signed-off-by: jinkun.hong <jinkun.hong at rock-chips.com>
>> Signed-off-by: Caesar Wang <caesar.wang at rock-chips.com>
>>
>> ---
>>
>> Changes in v11:
>>      - fix pm_genpd_init(&pd->genpd, NULL, false);
>>
>> Changes in v10:
>>      - this switches over domain infos to use masks instead of recomputing
>>        them each time and also gets rid of custom domain translator and
>>        uses standard onecell on.
>>
>> Changes in v9:
>>      - fix v8 changes as follows:
>>      - This reconciles the v2 and v7 code so that we power domain have
>>        lists of clocks they toggle on and off during power transitions and
>>        independently from power domains clocks we attach clocks to devices
>>        comprising power domain and prepare them so they are turn on and off
>>        by runtime PM.
>>      - add rockchip_pm_add_one_domain() to control domains.
>>      - add pd_start/pd_stop interface to control clocks
>>
>> Changes in v8:
>>      - This reconciles the v2 and v7 code so that we power domain have
>>        lists of clocks they toggle on and off during power transitions and
>>        independently from power domains clocks we attach clocks to devices
>>        comprising power domain and prepare them so they are turn on and off
>>        by runtime PM.
>>
>> Changes in v7:
>>      - Delete unused variables
>>
>> Changes in v6:
>>      - delete pmu_lock
>>      - modify dev_lock using mutex
>>      - pm_clk_resume(pd->dev) change to pm_clk_resume(ed->dev)
>>      - pm_clk_suspend(pd->dev) change to pm_clk_suspend(ed->dev)
>>      - add devm_kfree(pd->dev, de) in rockchip_pm_domain_detach_dev
>>
>> 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       | 471 ++++++++++++++++++++++++++++++
>>   include/dt-bindings/power-domain/rk3288.h |  11 +
>>   4 files changed, 484 insertions(+)
>>   create mode 100644 arch/arm/mach-rockchip/pm_domains.c
>>   create mode 100644 include/dt-bindings/power-domain/rk3288.h
>>
>> diff --git a/arch/arm/mach-rockchip/Kconfig b/arch/arm/mach-rockchip/Kconfig
>> index ac5803c..d033993 100644
>> --- a/arch/arm/mach-rockchip/Kconfig
>> +++ b/arch/arm/mach-rockchip/Kconfig
>> @@ -13,6 +13,7 @@ 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..17ea082 100644
>> --- a/arch/arm/mach-rockchip/Makefile
>> +++ b/arch/arm/mach-rockchip/Makefile
>> @@ -1,4 +1,5 @@
>>   CFLAGS_platsmp.o := -march=armv7-a
>>
>>   obj-$(CONFIG_ARCH_ROCKCHIP) += rockchip.o
>> +obj-$(CONFIG_PM_GENERIC_DOMAINS) += pm_domains.o
>>   obj-$(CONFIG_SMP) += headsmp.o platsmp.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..00730eb
>> --- /dev/null
>> +++ b/arch/arm/mach-rockchip/pm_domains.c
>> @@ -0,0 +1,471 @@
>> +/*
>> + * Rockchip Generic power domain support.
>> + *
>> + * Copyright (c) 2014 ROCKCHIP, Co. Ltd.
>> + *
>> + * 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/pm_clock.h>
>> +#include <linux/pm_domain.h>
>> +#include <linux/of_address.h>
>> +#include <linux/of_platform.h>
>> +#include <linux/clk.h>
>> +#include <linux/clk-provider.h>
>> +#include <linux/regmap.h>
>> +#include <linux/mfd/syscon.h>
>> +#include <dt-bindings/power-domain/rk3288.h>
>> +
>> +struct rockchip_domain_info {
>> +       int pwr_mask;
>> +       int status_mask;
>> +       int req_mask;
>> +       int idle_mask;
>> +       int ack_mask;
>> +};
>> +
>> +struct rockchip_pmu_info {
>> +       u32 pwr_offset;
>> +       u32 status_offset;
>> +       u32 req_offset;
>> +       u32 idle_offset;
>> +       u32 ack_offset;
>> +
>> +       int num_domains;
>> +       const struct rockchip_domain_info *domain_info;
>> +};
>> +
>> +struct rockchip_pm_domain {
>> +       struct generic_pm_domain genpd;
>> +       const struct rockchip_domain_info *info;
>> +       struct rockchip_pmu *pmu;
>> +       int num_clks;
>> +       struct clk *clks[];
>> +};
>> +
>> +struct rockchip_pmu {
>> +       struct device *dev;
>> +       struct regmap *regmap;
>> +       const struct rockchip_pmu_info *info;
>> +       struct mutex mutex; /* mutex lock for pmu */
>> +       struct genpd_onecell_data genpd_data;
>> +       struct generic_pm_domain *domains[];
>> +};
>> +
>> +#define to_rockchip_pd(gpd) container_of(gpd, struct rockchip_pm_domain, genpd)
>> +
>> +#define DOMAIN(pwr, status, req, idle, ack)    \
>> +{                                              \
>> +       .pwr_mask = BIT(pwr),                   \
>> +       .status_mask = BIT(status),             \
>> +       .req_mask = BIT(req),                   \
>> +       .idle_mask = BIT(idle),                 \
>> +       .ack_mask = BIT(ack),                   \
>> +}
>> +
>> +#define DOMAIN_RK3288(pwr, status, req)                \
>> +       DOMAIN(pwr, status, req, req, (req) + 16)
>> +
>> +static bool rockchip_pmu_domain_is_idle(struct rockchip_pm_domain *pd)
>> +{
>> +       struct rockchip_pmu *pmu = pd->pmu;
>> +       const struct rockchip_domain_info *pd_info = pd->info;
>> +       unsigned int val;
>> +
>> +       regmap_read(pmu->regmap, pmu->info->idle_offset, &val);
>> +       return (val & pd_info->idle_mask) == pd_info->idle_mask;
>> +}
>> +
>> +static int rockchip_pmu_set_idle_request(struct rockchip_pm_domain *pd,
>> +                                        bool idle)
>> +{
>> +       const struct rockchip_domain_info *pd_info = pd->info;
>> +       struct rockchip_pmu *pmu = pd->pmu;
>> +       unsigned int val;
>> +
>> +       regmap_update_bits(pmu->regmap, pmu->info->req_offset,
>> +                          pd_info->req_mask, idle ? -1U : 0);
>> +
>> +       dsb();
>> +
>> +       do {
>> +               regmap_read(pmu->regmap, pmu->info->ack_offset, &val);
>> +       } while ((val & pd_info->ack_mask) != (idle ? pd_info->ack_mask : 0));
> Hi Caesar,
>
>
> just a nit:
> it would be slightly cleaner if you created a function for this like
> you did for rockchip_pmu_domain_is_idle():
>
> static bool rockchip_pmu_domain_is_ack(struct rockchip_pm_domain *pd)
> {
>         struct rockchip_pmu *pmu = pd->pmu;
>         const struct rockchip_domain_info *pd_info = pd->info;
>         unsigned int val;
>
>         regmap_read(pmu->regmap, pmu->info->ack_offset, &val);
>         return (val & pd_info->ack_mask) == pd_info->ack_mask;
> }
>
> ...
>
>    while (rockchip_pmu_domain_is_ack(pd) != idle)
>      cpu_relax();

Fixed.


>> +
>> +       while (rockchip_pmu_domain_is_idle(pd) != idle)
>> +               cpu_relax();
>> +
>> +       return 0;
>> +}
>> +
>> +static bool rockchip_pmu_domain_is_on(struct rockchip_pm_domain *pd)
>> +{
>> +       struct rockchip_pmu *pmu = pd->pmu;
>> +       unsigned int val;
>> +
>> +       regmap_read(pmu->regmap, pmu->info->status_offset, &val);
>> +
>> +       /* 1'b0: power on, 1'b1: power off */
>> +       return !(val & pd->info->status_mask);
>> +}
>> +
>> +static void rockchip_do_pmu_set_power_domain(struct rockchip_pm_domain *pd,
>> +                                            bool on)
>> +{
>> +       struct rockchip_pmu *pmu = pd->pmu;
>> +
>> +       regmap_update_bits(pmu->regmap, pmu->info->pwr_offset,
>> +                          pd->info->pwr_mask, on ? 0 : -1U);
>> +
>> +       dsb();
>> +
>> +       while (rockchip_pmu_domain_is_on(pd) != on)
>> +               cpu_relax();
>> +}
>> +
>> +static int rockchip_pd_power(struct rockchip_pm_domain *pd, bool power_on)
>> +{
>> +       int i;
>> +
>> +       mutex_lock(&pd->pmu->mutex);
>> +
>> +       if (rockchip_pmu_domain_is_on(pd) != power_on) {
>> +               for (i = 0; i < pd->num_clks; i++)
>> +                       clk_enable(pd->clks[i]);
>> +
>> +               if (!power_on) {
>> +                       /* FIXME: add code to save AXI_QOS */
>> +
>> +                       /* if powering down, idle request to NIU first */
>> +                       rockchip_pmu_set_idle_request(pd, true);
>> +               }
>> +
>> +               rockchip_do_pmu_set_power_domain(pd, power_on);
>> +
>> +               if (power_on) {
>> +                       /* if powering up, leave idle mode */
>> +                       rockchip_pmu_set_idle_request(pd, false);
>> +
>> +                       /* FIXME: add code to restore AXI_QOS */
>> +               }
>> +
>> +               for (i = pd->num_clks - 1; i >= 0; i--)
>> +                       clk_disable(pd->clks[i]);
>> +       }
>> +
>> +       mutex_unlock(&pd->pmu->mutex);
>> +       return 0;
>> +}
>> +
>> +static int rockchip_pd_power_on(struct generic_pm_domain *domain)
>> +{
>> +       struct rockchip_pm_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_pm_domain *pd = to_rockchip_pd(domain);
>> +
>> +       return rockchip_pd_power(pd, false);
>> +}
>> +
>> +static void rockchip_pd_attach_dev(struct device *dev)
>> +{
>> +       struct generic_pm_domain *genpd = pd_to_genpd(dev->pm_domain);
>> +       struct clk *clk;
>> +       int i;
>> +       int error;
>> +
>> +       dev_dbg(dev, "attaching to power domain '%s'\n", genpd->name);
>> +
>> +       error = pm_clk_create(dev);
>> +       if (error) {
>> +               dev_err(dev, "pm_clk_create failed %d\n", error);
>> +               return;
>> +       }
>> +
>> +       while ((clk = of_clk_get(dev->of_node, i++)) && !IS_ERR(clk)) {
>> +               error = pm_clk_add_clk(dev, clk);
>> +               clk_put(clk);
>> +               if (error) {
>> +                       dev_err(dev, "pm_clk_add_clk failed %d\n", error);
>> +                       pm_clk_destroy(dev);
>> +                       return;
>> +               }
>> +               dev_dbg(dev, "added clock '%s' to list of PM clocks\n",
>> +                       __clk_get_name(clk));
>> +       }
>> +}
>> +
>> +static void rockchip_pd_detach_dev(struct device *dev)
>> +{
>> +       struct generic_pm_domain *genpd = pd_to_genpd(dev->pm_domain);
>> +
>> +       dev_dbg(dev, "detaching from power domain %s\n", genpd->name);
>> +
>> +       pm_clk_destroy(dev);
>> +}
>> +
>> +static int rockchip_pd_start_dev(struct device *dev)
>> +{
>> +       struct generic_pm_domain *genpd = pd_to_genpd(dev->pm_domain);
>> +
>> +       dev_dbg(dev, "starting device in power domain '%s'\n", genpd->name);
>> +
>> +       return pm_clk_resume(dev);
>> +}
>> +
>> +static int rockchip_pd_stop_dev(struct device *dev)
>> +{
>> +       struct generic_pm_domain *genpd = pd_to_genpd(dev->pm_domain);
>> +
>> +       dev_dbg(dev, "stopping device in power domain '%s'\n", genpd->name);
>> +
>> +       return pm_clk_suspend(dev);
>> +}
>> +
>> +static int rockchip_pm_add_one_domain(struct rockchip_pmu *pmu,
>> +                                     struct device_node *node)
>> +{
>> +       const struct rockchip_domain_info *pd_info;
>> +       struct rockchip_pm_domain *pd;
>> +       struct clk *clk;
>> +       int clk_cnt;
>> +       int i;
>> +       u32 id;
>> +       bool is_on;
>> +       int error;
>> +
>> +       error = of_property_read_u32(node, "reg", &id);
>> +       if (error) {
>> +               dev_err(pmu->dev,
>> +                       "%s: failed to retrieve domain id (reg): %d\n",
>> +                       node->name, error);
>> +               return -EINVAL;
>> +       }
>> +
>> +       if (id >= pmu->info->num_domains) {
>> +               dev_err(pmu->dev, "%s: invalid domain id %d\n",
>> +                       node->name, id);
>> +               return -EINVAL;
>> +       }
>> +
>> +       pd_info = &pmu->info->domain_info[id];
>> +       if (!pd_info) {
>> +               dev_err(pmu->dev, "%s: undefined domain id %d\n",
>> +                       node->name, id);
>> +               return -EINVAL;
>> +       }
>> +
>> +       clk_cnt = of_count_phandle_with_args(node, "clocks", "#clock-cells");
>> +       pd = devm_kzalloc(pmu->dev,
>> +                         sizeof(*pd) + clk_cnt * sizeof(pd->clks[0]),
>> +                         GFP_KERNEL);
>> +       if (!pd)
>> +               return -ENOMEM;
>> +
>> +       pd->genpd.name = node->name;
>> +       pd->genpd.power_off = rockchip_pd_power_off;
>> +       pd->genpd.power_on = rockchip_pd_power_on;
>> +       pd->genpd.attach_dev = rockchip_pd_attach_dev;
>> +       pd->genpd.detach_dev = rockchip_pd_detach_dev;
>> +       pd->genpd.dev_ops.start = rockchip_pd_start_dev;
>> +       pd->genpd.dev_ops.stop = rockchip_pd_stop_dev;
>> +
>> +       pd->info = pd_info;
>> +       pd->pmu = pmu;
>> +       pd->num_clks = clk_cnt;
>> +
>> +       is_on = rockchip_pmu_domain_is_on(pd);
>> +       pm_genpd_init(&pd->genpd, NULL, !is_on);
>> +
>> +       for (i = 0; i < clk_cnt; i++) {
>> +               clk = of_clk_get(node, i);
>> +               if (IS_ERR(clk)) {
>> +                       error = PTR_ERR(clk);
>> +                       dev_err(pmu->dev,
>> +                               "%s: failed to get clk %s (index %d): %d\n",
>> +                               node->name, __clk_get_name(clk), i, error);
>> +                       goto err_out;
>> +               }
>> +
>> +               error = clk_prepare(clk);
>> +               if (error) {
>> +                       dev_err(pmu->dev,
>> +                               "%s: failed to prepare clk %s (index %d): %d\n",
>> +                               node->name, __clk_get_name(clk), i, error);
>> +                       clk_put(clk);
>> +                       goto err_out;
>> +               }
>> +
>> +               pd->clks[i] = clk;
>> +
>> +               dev_dbg(pmu->dev, "added clock '%s' to domain '%s'\n",
>> +                       __clk_get_name(clk), node->name);
>> +       }
>> +
>> +       pmu->genpd_data.domains[id] = &pd->genpd;
>> +       return 0;
>> +
>> +err_out:
>> +       while (--i >= 0) {
>> +               clk_unprepare(pd->clks[i]);
>> +               clk_put(pd->clks[i]);
>> +       }
>> +       return error;
>> +}
>> +
>> +static void rockchip_pm_remove_one_domain(struct rockchip_pm_domain *pd)
>> +{
>> +       int i;
>> +
>> +       for (i = 0; i < pd->num_clks; i++) {
>> +               clk_unprepare(pd->clks[i]);
>> +               clk_put(pd->clks[i]);
>> +       }
>> +
>> +       /* devm will free our memory */
>> +}
>> +
>> +static void rockchip_pm_domain_cleanup(struct rockchip_pmu *pmu)
>> +{
>> +       struct generic_pm_domain *genpd;
>> +       struct rockchip_pm_domain *pd;
>> +       int i;
>> +
>> +       for (i = 0; i < pmu->genpd_data.num_domains; i++) {
>> +               genpd = pmu->genpd_data.domains[i];
>> +               if (genpd) {
>> +                       pd = to_rockchip_pd(genpd);
>> +                       rockchip_pm_remove_one_domain(pd);
>> +               }
>> +       }
>> +
>> +       /* devm will free our memory */
>> +}
>> +
>> +static int rockchip_pm_domain_probe(struct platform_device *pdev)
>> +{
>> +       struct device *dev = &pdev->dev;
>> +       struct device_node *np = dev->of_node;
>> +       struct device_node *node;
>> +       struct rockchip_pmu *pmu;
>> +       const struct of_device_id *match;
>> +       const struct rockchip_pmu_info *pmu_info;
>> +       int error;
>> +
>> +       if (!np) {
>> +               dev_err(dev, "device tree node not found\n");
>> +               return -ENXIO;
>> +       }
>> +
>> +       match = of_match_device(dev->driver->of_match_table, dev);
>> +       if (!match || !match->data) {
>> +               dev_err(dev, "missing pmu data\n");
>> +               return -EINVAL;
>> +       }
>> +
>> +       pmu_info = match->data;
>> +
>> +       pmu = devm_kzalloc(dev,
>> +                          sizeof(*pmu) +
>> +                               pmu_info->num_domains * sizeof(pmu->domains[0]),
>> +                          GFP_KERNEL);
>> +       if (!pmu)
>> +               return -ENOMEM;
>> +
>> +       pmu->dev = &pdev->dev;
>> +       mutex_init(&pmu->mutex);
>> +
>> +       pmu->info = pmu_info;
>> +
>> +       pmu->genpd_data.domains = pmu->domains;
>> +       pmu->genpd_data.num_domains = pmu_info->num_domains;
>> +
>> +       node = of_parse_phandle(np, "rockchip,pmu", 0);
>> +       pmu->regmap = syscon_node_to_regmap(node);
>> +       of_node_put(node);
>> +       if (IS_ERR(pmu->regmap)) {
>> +               error = PTR_ERR(pmu->regmap);
>> +               dev_err(dev, "failed to get PMU regmap: %d\n", error);
>> +               return error;
>> +       }
>> +
>> +       error = -ENXIO;
>> +
>> +       for_each_available_child_of_node(np, node) {
>> +               error = rockchip_pm_add_one_domain(pmu, node);
>> +               if (error) {
>> +                       dev_err(dev, "failed to handle node %s: %d\n",
>> +                               node->name, error);
>> +                       goto err_out;
>> +               }
>> +       }
>> +
>> +       if (error) {
>> +               dev_dbg(dev, "no power domains defined\n");
> Perhaps dev_err() or dev_warn(), to ensure this message is seen.
> But, not have defined power domains doesn't seem like a fatal error.
> Perhaps just return 0?
>
> -Daniel
>

Fixed.


Thanks!
>> +               goto err_out;
>> +       }
>> +
>> +       of_genpd_add_provider_onecell(np, &pmu->genpd_data);
>> +
>> +       return 0;
>> +
>> +err_out:
>> +       rockchip_pm_domain_cleanup(pmu);
>> +       return error;
>> +}
>> +
>> +static const struct rockchip_domain_info rk3288_pm_domains[] = {
>> +       [RK3288_PD_GPU]         = DOMAIN_RK3288(9, 9, 2),
>> +       [RK3288_PD_VIO]         = DOMAIN_RK3288(7, 7, 4),
>> +       [RK3288_PD_VIDEO]       = DOMAIN_RK3288(8, 8, 3),
>> +       [RK3288_PD_HEVC]        = DOMAIN_RK3288(14, 10, 9),
>> +};
>> +
>> +static const struct rockchip_pmu_info rk3288_pmu = {
>> +       .pwr_offset = 0x08,
>> +       .status_offset = 0x0c,
>> +       .req_offset = 0x10,
>> +       .idle_offset = 0x14,
>> +       .ack_offset = 0x14,
>> +       .num_domains = ARRAY_SIZE(rk3288_pm_domains),
>> +       .domain_info = rk3288_pm_domains,
>> +};
>> +
>> +static const struct of_device_id rockchip_pm_domain_dt_match[] = {
>> +       {
>> +               .compatible = "rockchip,rk3288-power-controller",
>> +               .data = (void *)&rk3288_pmu,
>> +       },
>> +       { /* sentinel */ },
>> +};
>> +MODULE_DEVICE_TABLE(of, rockchip_pm_domain_dt_match);
>> +
>> +static struct platform_driver rockchip_pm_domain_driver = {
>> +       .probe = rockchip_pm_domain_probe,
>> +       .driver = {
>> +               .name   = "rockchip-pm-domain",
>> +               .owner  = THIS_MODULE,
>> +               .of_match_table = rockchip_pm_domain_dt_match,
>> +               /*
>> +                * We can't forcibly eject devices form power domain,
>> +                * so we can't really remove power domains once they
>> +                * were added.
>> +                */
>> +               .suppress_bind_attrs = true,
>> +       },
>> +};
>> +
>> +static int __init rockchip_pm_domain_drv_register(void)
>> +{
>> +       return platform_driver_register(&rockchip_pm_domain_driver);
>> +}
>> +postcore_initcall(rockchip_pm_domain_drv_register);
>> diff --git a/include/dt-bindings/power-domain/rk3288.h b/include/dt-bindings/power-domain/rk3288.h
>> new file mode 100644
>> index 0000000..ca68c11
>> --- /dev/null
>> +++ b/include/dt-bindings/power-domain/rk3288.h
>> @@ -0,0 +1,11 @@
>> +#ifndef __DT_BINDINGS_POWER_DOMAIN_RK3288_H__
>> +#define __DT_BINDINGS_POWER_DOMAIN_RK3288_H__
>> +
>> +/* RK3288 power domain index */
>> +#define RK3288_PD_GPU          0
>> +#define RK3288_PD_VIO          1
>> +#define RK3288_PD_VIDEO        2
>> +#define RK3288_PD_HEVC         3
>> +#define RK3288_PD_PERI         4
>> +
>> +#endif
>> --
>> 1.9.1
>>
>>
>>
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>> Linux-rockchip at lists.infradead.org
>> http://lists.infradead.org/mailman/listinfo/linux-rockchip
>
>

-- 
Best regards,
Caesar





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