From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lina Iyer Subject: Re: [PATCH v2 3/8] PM / Domains: Allow domain power states to be read from DT Date: Mon, 10 Oct 2016 09:03:01 -0600 Message-ID: <20161010150301.GA44885@linaro.org> References: <1475879821-8035-1-git-send-email-lina.iyer@linaro.org> <1475879821-8035-4-git-send-email-lina.iyer@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Return-path: Received: from mail-pa0-f47.google.com ([209.85.220.47]:35522 "EHLO mail-pa0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753099AbcJJPDF (ORCPT ); Mon, 10 Oct 2016 11:03:05 -0400 Received: by mail-pa0-f47.google.com with SMTP id qn10so52047301pac.2 for ; Mon, 10 Oct 2016 08:03:05 -0700 (PDT) Content-Disposition: inline In-Reply-To: Sender: linux-arm-msm-owner@vger.kernel.org List-Id: linux-arm-msm@vger.kernel.org To: Ulf Hansson Cc: Kevin Hilman , "Rafael J. Wysocki" , "linux-pm@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , Andy Gross , Stephen Boyd , "linux-arm-msm@vger.kernel.org" , Brendan Jackman , Lorenzo Pieralisi , Sudeep Holla , Juri Lelli , Marc Titinger On Mon, Oct 10 2016 at 04:01 -0600, Ulf Hansson wrote: >On 8 October 2016 at 00:36, Lina Iyer wrote: >> This patch allows domains to define idle states in the DT. SoC's can >> define domain idle states in DT using the "domain-idle-states" property >> of the domain provider. Add API to read the idle states from DT that can >> be set in the genpd object. >> >> This patch is based on the original patch by Marc Titinger. >> >> Signed-off-by: Marc Titinger >> Signed-off-by: Ulf Hansson >> Signed-off-by: Lina Iyer >> --- >> drivers/base/power/domain.c | 95 +++++++++++++++++++++++++++++++++++++++++++++ >> include/linux/pm_domain.h | 8 ++++ >> 2 files changed, 103 insertions(+) >> >> diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c >> index 4e87170..4208b67 100644 >> --- a/drivers/base/power/domain.c >> +++ b/drivers/base/power/domain.c >> @@ -1917,6 +1917,101 @@ out: >> return ret ? -EPROBE_DEFER : 0; >> } >> EXPORT_SYMBOL_GPL(genpd_dev_pm_attach); >> + >> +static const struct of_device_id idle_state_match[] = { >> + { .compatible = "arm,idle-state", }, >> + { } >> +}; >> + >> +static int genpd_parse_state(struct genpd_power_state *genpd_state, >> + struct device_node *state_node) >> +{ >> + int err; >> + u32 residency; >> + u32 entry_latency, exit_latency; >> + const struct of_device_id *match_id; >> + >> + match_id = of_match_node(idle_state_match, state_node); >> + if (!match_id) >> + return -EINVAL; >> + >> + err = of_property_read_u32(state_node, "entry-latency-us", >> + &entry_latency); >> + if (err) { >> + pr_debug(" * %s missing entry-latency-us property\n", >> + state_node->full_name); >> + return -EINVAL; >> + } >> + >> + err = of_property_read_u32(state_node, "exit-latency-us", >> + &exit_latency); >> + if (err) { >> + pr_debug(" * %s missing exit-latency-us property\n", >> + state_node->full_name); >> + return -EINVAL; >> + } >> + >> + err = of_property_read_u32(state_node, "min-residency-us", &residency); >> + if (!err) >> + genpd_state->residency_ns = 1000 * residency; >> + >> + genpd_state->power_on_latency_ns = 1000 * exit_latency; >> + genpd_state->power_off_latency_ns = 1000 * entry_latency; >> + >> + return 0; >> +} >> + >> +/** >> + * of_genpd_parse_idle_states: Return array of idle states for the genpd. >> + * >> + * @dn: The genpd device node >> + * @states: The pointer to which the state array will be saved. >> + * @n: The count of elements in the array returned from this function. >> + * >> + * Returns the device states parsed from the OF node. The memory for the states >> + * is allocated by this function and is the responsibility of the caller to >> + * free the memory after use. >> + */ >> +int of_genpd_parse_idle_states(struct device_node *dn, >> + struct genpd_power_state **states, int *n) > >Instead of taking **states as a parameter, let's instead return it as >a pointer for the allocated struct. In case of failures, let's return >ERR_PTR(). > Hmm.. I thought about it. There are 2 return values from this function. If we return a pointer to the allocated memory, we still have to return the size of it as an argument. I wasn't happy splitting the return values in 2 different places. >> +{ >> + struct genpd_power_state *st; >> + struct device_node *np; >> + int i = 0; >> + int err, ret; >> + int count; >> + struct of_phandle_iterator it; >> + >> + count = of_count_phandle_with_args(dn, "domain-idle-states", NULL); > >If count is zero or an error, we should return an error code (ERR_PTR()). Right? > OK >> + >> + st = kcalloc(count, sizeof(*st), GFP_KERNEL); >> + if (!st) >> + return -ENOMEM; >> + >> + /* Loop over the phandles until all the requested entry is found */ >> + of_for_each_phandle(&it, err, dn, "domain-idle-states", NULL, 0) { >> + np = of_node_get(it.node); > >I don't think you need to increment the usage count for the device >node as that is already managed by of_for_each_phandle(). > >It's only in the error case below, when it's needed. > Hmm.. Didn't realize that.. will fix. >> + ret = genpd_parse_state(&st[i++], np); >> + if (ret) { >> + pr_err >> + ("Parsing idle state node %s failed with err %d\n", >> + np->full_name, ret); >> + of_node_put(np); >> + goto fail; > >The goto seems unnecessary. Why not deal with all error handling here >and return the error code? > >> + } >> + of_node_put(np); > >According the comment above, you should be able to remove this. > >> + } >> + >> + *n = count; >> + *states = st; >> + >> + return 0; >> +fail: >> + kfree(st); >> + return ret; >> +} >> +EXPORT_SYMBOL(of_genpd_parse_idle_states); > >Please use EXPORT_SYMBOL_GPL() instead. > Hmm.. OK Thanks, Lina >> + >> #endif /* CONFIG_PM_GENERIC_DOMAINS_OF */ >> >> >> diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h >> index f4492eb..b489496 100644 >> --- a/include/linux/pm_domain.h >> +++ b/include/linux/pm_domain.h >> @@ -205,6 +205,8 @@ extern int of_genpd_add_device(struct of_phandle_args *args, >> extern int of_genpd_add_subdomain(struct of_phandle_args *parent, >> struct of_phandle_args *new_subdomain); >> extern struct generic_pm_domain *of_genpd_remove_last(struct device_node *np); >> +extern int of_genpd_parse_idle_states(struct device_node *dn, >> + struct genpd_power_state **states, int *n); >> >> int genpd_dev_pm_attach(struct device *dev); >> #else /* !CONFIG_PM_GENERIC_DOMAINS_OF */ >> @@ -234,6 +236,12 @@ static inline int of_genpd_add_subdomain(struct of_phandle_args *parent, >> return -ENODEV; >> } >> >> +static inline int of_genpd_parse_idle_states(struct device_node *dn, >> + struct genpd_power_state **states, int *n) >> +{ >> + return -ENODEV; >> +} >> + >> static inline int genpd_dev_pm_attach(struct device *dev) >> { >> return -ENODEV; >> -- >> 2.7.4 >> > >Kind regards >Uffe From mboxrd@z Thu Jan 1 00:00:00 1970 From: lina.iyer@linaro.org (Lina Iyer) Date: Mon, 10 Oct 2016 09:03:01 -0600 Subject: [PATCH v2 3/8] PM / Domains: Allow domain power states to be read from DT In-Reply-To: References: <1475879821-8035-1-git-send-email-lina.iyer@linaro.org> <1475879821-8035-4-git-send-email-lina.iyer@linaro.org> Message-ID: <20161010150301.GA44885@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Mon, Oct 10 2016 at 04:01 -0600, Ulf Hansson wrote: >On 8 October 2016 at 00:36, Lina Iyer wrote: >> This patch allows domains to define idle states in the DT. SoC's can >> define domain idle states in DT using the "domain-idle-states" property >> of the domain provider. Add API to read the idle states from DT that can >> be set in the genpd object. >> >> This patch is based on the original patch by Marc Titinger. >> >> Signed-off-by: Marc Titinger >> Signed-off-by: Ulf Hansson >> Signed-off-by: Lina Iyer >> --- >> drivers/base/power/domain.c | 95 +++++++++++++++++++++++++++++++++++++++++++++ >> include/linux/pm_domain.h | 8 ++++ >> 2 files changed, 103 insertions(+) >> >> diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c >> index 4e87170..4208b67 100644 >> --- a/drivers/base/power/domain.c >> +++ b/drivers/base/power/domain.c >> @@ -1917,6 +1917,101 @@ out: >> return ret ? -EPROBE_DEFER : 0; >> } >> EXPORT_SYMBOL_GPL(genpd_dev_pm_attach); >> + >> +static const struct of_device_id idle_state_match[] = { >> + { .compatible = "arm,idle-state", }, >> + { } >> +}; >> + >> +static int genpd_parse_state(struct genpd_power_state *genpd_state, >> + struct device_node *state_node) >> +{ >> + int err; >> + u32 residency; >> + u32 entry_latency, exit_latency; >> + const struct of_device_id *match_id; >> + >> + match_id = of_match_node(idle_state_match, state_node); >> + if (!match_id) >> + return -EINVAL; >> + >> + err = of_property_read_u32(state_node, "entry-latency-us", >> + &entry_latency); >> + if (err) { >> + pr_debug(" * %s missing entry-latency-us property\n", >> + state_node->full_name); >> + return -EINVAL; >> + } >> + >> + err = of_property_read_u32(state_node, "exit-latency-us", >> + &exit_latency); >> + if (err) { >> + pr_debug(" * %s missing exit-latency-us property\n", >> + state_node->full_name); >> + return -EINVAL; >> + } >> + >> + err = of_property_read_u32(state_node, "min-residency-us", &residency); >> + if (!err) >> + genpd_state->residency_ns = 1000 * residency; >> + >> + genpd_state->power_on_latency_ns = 1000 * exit_latency; >> + genpd_state->power_off_latency_ns = 1000 * entry_latency; >> + >> + return 0; >> +} >> + >> +/** >> + * of_genpd_parse_idle_states: Return array of idle states for the genpd. >> + * >> + * @dn: The genpd device node >> + * @states: The pointer to which the state array will be saved. >> + * @n: The count of elements in the array returned from this function. >> + * >> + * Returns the device states parsed from the OF node. The memory for the states >> + * is allocated by this function and is the responsibility of the caller to >> + * free the memory after use. >> + */ >> +int of_genpd_parse_idle_states(struct device_node *dn, >> + struct genpd_power_state **states, int *n) > >Instead of taking **states as a parameter, let's instead return it as >a pointer for the allocated struct. In case of failures, let's return >ERR_PTR(). > Hmm.. I thought about it. There are 2 return values from this function. If we return a pointer to the allocated memory, we still have to return the size of it as an argument. I wasn't happy splitting the return values in 2 different places. >> +{ >> + struct genpd_power_state *st; >> + struct device_node *np; >> + int i = 0; >> + int err, ret; >> + int count; >> + struct of_phandle_iterator it; >> + >> + count = of_count_phandle_with_args(dn, "domain-idle-states", NULL); > >If count is zero or an error, we should return an error code (ERR_PTR()). Right? > OK >> + >> + st = kcalloc(count, sizeof(*st), GFP_KERNEL); >> + if (!st) >> + return -ENOMEM; >> + >> + /* Loop over the phandles until all the requested entry is found */ >> + of_for_each_phandle(&it, err, dn, "domain-idle-states", NULL, 0) { >> + np = of_node_get(it.node); > >I don't think you need to increment the usage count for the device >node as that is already managed by of_for_each_phandle(). > >It's only in the error case below, when it's needed. > Hmm.. Didn't realize that.. will fix. >> + ret = genpd_parse_state(&st[i++], np); >> + if (ret) { >> + pr_err >> + ("Parsing idle state node %s failed with err %d\n", >> + np->full_name, ret); >> + of_node_put(np); >> + goto fail; > >The goto seems unnecessary. Why not deal with all error handling here >and return the error code? > >> + } >> + of_node_put(np); > >According the comment above, you should be able to remove this. > >> + } >> + >> + *n = count; >> + *states = st; >> + >> + return 0; >> +fail: >> + kfree(st); >> + return ret; >> +} >> +EXPORT_SYMBOL(of_genpd_parse_idle_states); > >Please use EXPORT_SYMBOL_GPL() instead. > Hmm.. OK Thanks, Lina >> + >> #endif /* CONFIG_PM_GENERIC_DOMAINS_OF */ >> >> >> diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h >> index f4492eb..b489496 100644 >> --- a/include/linux/pm_domain.h >> +++ b/include/linux/pm_domain.h >> @@ -205,6 +205,8 @@ extern int of_genpd_add_device(struct of_phandle_args *args, >> extern int of_genpd_add_subdomain(struct of_phandle_args *parent, >> struct of_phandle_args *new_subdomain); >> extern struct generic_pm_domain *of_genpd_remove_last(struct device_node *np); >> +extern int of_genpd_parse_idle_states(struct device_node *dn, >> + struct genpd_power_state **states, int *n); >> >> int genpd_dev_pm_attach(struct device *dev); >> #else /* !CONFIG_PM_GENERIC_DOMAINS_OF */ >> @@ -234,6 +236,12 @@ static inline int of_genpd_add_subdomain(struct of_phandle_args *parent, >> return -ENODEV; >> } >> >> +static inline int of_genpd_parse_idle_states(struct device_node *dn, >> + struct genpd_power_state **states, int *n) >> +{ >> + return -ENODEV; >> +} >> + >> static inline int genpd_dev_pm_attach(struct device *dev) >> { >> return -ENODEV; >> -- >> 2.7.4 >> > >Kind regards >Uffe