From: Vitor Soares vitor.soares@toradex.com
During the probe, the genpd power_dev is added to the dpm_list after blk_ctrl due to its parent/child relationship. Making the blk_ctrl suspend after and resume before the genpd power_dev.
As a consequence, the system hangs when resuming the VPU due to the power domain dependency.
To ensure the proper suspend/resume order, add a device link betweem blk_ctrl and genpd power_dev. It guarantees genpd power_dev is suspended after and resumed before blk-ctrl.
Cc: stable@vger.kernel.org Closes: https://lore.kernel.org/all/fccbb040330a706a4f7b34875db1d896a0bf81c8.camel@g... Link: https://lore.kernel.org/all/20240409085802.290439-1-ivitro@gmail.com/ Fixes: 2684ac05a8c4 ("soc: imx: add i.MX8M blk-ctrl driver") Suggested-by: Lucas Stach l.stach@pengutronix.de Signed-off-by: Vitor Soares vitor.soares@toradex.com ---
This is a new patch, but is a follow-up of: https://lore.kernel.org/all/20240409085802.290439-1-ivitro@gmail.com/
As suggested by Lucas, we are addressing this PM issue in the imx8m-blk-ctrl driver instead of in the imx8mm.dtsi.
drivers/pmdomain/imx/imx8m-blk-ctrl.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)
diff --git a/drivers/pmdomain/imx/imx8m-blk-ctrl.c b/drivers/pmdomain/imx/imx8m-blk-ctrl.c index ca942d7929c2..cd0d2296080d 100644 --- a/drivers/pmdomain/imx/imx8m-blk-ctrl.c +++ b/drivers/pmdomain/imx/imx8m-blk-ctrl.c @@ -283,6 +283,20 @@ static int imx8m_blk_ctrl_probe(struct platform_device *pdev) goto cleanup_pds; }
+ /* + * Enforce suspend/resume ordering by making genpd power_dev a + * provider of blk-ctrl. Genpd power_dev is suspended after and + * resumed before blk-ctrl. + */ + if (!device_link_add(dev, domain->power_dev, DL_FLAG_STATELESS)) { + ret = -EINVAL; + dev_err_probe(dev, ret, + "failed to link to %s\n", data->name); + pm_genpd_remove(&domain->genpd); + dev_pm_domain_detach(domain->power_dev, true); + goto cleanup_pds; + } + /* * We use runtime PM to trigger power on/off of the upstream GPC * domain, as a strict hierarchical parent/child power domain @@ -324,6 +338,7 @@ static int imx8m_blk_ctrl_probe(struct platform_device *pdev) of_genpd_del_provider(dev->of_node); cleanup_pds: for (i--; i >= 0; i--) { + device_link_remove(dev, bc->domains[i].power_dev); pm_genpd_remove(&bc->domains[i].genpd); dev_pm_domain_detach(bc->domains[i].power_dev, true); } @@ -343,6 +358,7 @@ static void imx8m_blk_ctrl_remove(struct platform_device *pdev) for (i = 0; bc->onecell_data.num_domains; i++) { struct imx8m_blk_ctrl_domain *domain = &bc->domains[i];
+ device_link_remove(&pdev->dev, domain->power_dev); pm_genpd_remove(&domain->genpd); dev_pm_domain_detach(domain->power_dev, true); }
Hi Markus,
On Thu, 2024-04-18 at 18:24 +0200, Markus Elfring wrote:
…, add a device link betweem blk_ctrl and genpd power_dev. …
I hope that a typo will be avoided in this change description for the final commit.
Thanks for you feedback. I will fix it next version.
Best regards, Vitor Soares
Regards, Markus
On Thu, Apr 18, 2024 at 04:51:51PM +0100, Vitor Soares wrote:
From: Vitor Soares vitor.soares@toradex.com
During the probe, the genpd power_dev is added to the dpm_list after blk_ctrl due to its parent/child relationship. Making the blk_ctrl suspend after and resume before the genpd power_dev.
As a consequence, the system hangs when resuming the VPU due to the power domain dependency.
To ensure the proper suspend/resume order, add a device link betweem blk_ctrl and genpd power_dev. It guarantees genpd power_dev is suspended after and resumed before blk-ctrl.
Cc: Adam Ford
Francesco
On Wed, May 8, 2024 at 12:40 PM Francesco Dolcini francesco@dolcini.it wrote:
On Thu, Apr 18, 2024 at 04:51:51PM +0100, Vitor Soares wrote:
From: Vitor Soares vitor.soares@toradex.com
During the probe, the genpd power_dev is added to the dpm_list after blk_ctrl due to its parent/child relationship. Making the blk_ctrl suspend after and resume before the genpd power_dev.
As a consequence, the system hangs when resuming the VPU due to the power domain dependency.
To ensure the proper suspend/resume order, add a device link betweem blk_ctrl and genpd power_dev. It guarantees genpd power_dev is suspended after and resumed before blk-ctrl.
Cc: Adam Ford
Thanks! This is what I was thinking from the other thread. I just didn't see this one.
adam
Francesco
Am Donnerstag, dem 18.04.2024 um 16:51 +0100 schrieb Vitor Soares:
From: Vitor Soares vitor.soares@toradex.com
During the probe, the genpd power_dev is added to the dpm_list after blk_ctrl due to its parent/child relationship. Making the blk_ctrl suspend after and resume before the genpd power_dev.
As a consequence, the system hangs when resuming the VPU due to the power domain dependency.
To ensure the proper suspend/resume order, add a device link betweem blk_ctrl and genpd power_dev. It guarantees genpd power_dev is suspended after and resumed before blk-ctrl.
Cc: stable@vger.kernel.org Closes: https://lore.kernel.org/all/fccbb040330a706a4f7b34875db1d896a0bf81c8.camel@g... Link: https://lore.kernel.org/all/20240409085802.290439-1-ivitro@gmail.com/ Fixes: 2684ac05a8c4 ("soc: imx: add i.MX8M blk-ctrl driver") Suggested-by: Lucas Stach l.stach@pengutronix.de Signed-off-by: Vitor Soares vitor.soares@toradex.com
Reviewed-by: Lucas Stach l.stach@pengutronix.de
This is a new patch, but is a follow-up of: https://lore.kernel.org/all/20240409085802.290439-1-ivitro@gmail.com/
As suggested by Lucas, we are addressing this PM issue in the imx8m-blk-ctrl driver instead of in the imx8mm.dtsi.
drivers/pmdomain/imx/imx8m-blk-ctrl.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)
diff --git a/drivers/pmdomain/imx/imx8m-blk-ctrl.c b/drivers/pmdomain/imx/imx8m-blk-ctrl.c index ca942d7929c2..cd0d2296080d 100644 --- a/drivers/pmdomain/imx/imx8m-blk-ctrl.c +++ b/drivers/pmdomain/imx/imx8m-blk-ctrl.c @@ -283,6 +283,20 @@ static int imx8m_blk_ctrl_probe(struct platform_device *pdev) goto cleanup_pds; }
/** Enforce suspend/resume ordering by making genpd power_dev a* provider of blk-ctrl. Genpd power_dev is suspended after and* resumed before blk-ctrl.*/if (!device_link_add(dev, domain->power_dev, DL_FLAG_STATELESS)) {ret = -EINVAL;dev_err_probe(dev, ret,"failed to link to %s\n", data->name);pm_genpd_remove(&domain->genpd);dev_pm_domain_detach(domain->power_dev, true);goto cleanup_pds;}- /*
- We use runtime PM to trigger power on/off of the upstream GPC
- domain, as a strict hierarchical parent/child power domain
@@ -324,6 +338,7 @@ static int imx8m_blk_ctrl_probe(struct platform_device *pdev) of_genpd_del_provider(dev->of_node); cleanup_pds: for (i--; i >= 0; i--) {
device_link_remove(dev, bc->domains[i].power_dev);@@ -343,6 +358,7 @@ static void imx8m_blk_ctrl_remove(struct platform_device *pdev) for (i = 0; bc->onecell_data.num_domains; i++) { struct imx8m_blk_ctrl_domain *domain = &bc->domains[i];
device_link_remove(&pdev->dev, domain->power_dev);
On Thu, 18 Apr 2024 at 17:52, Vitor Soares ivitro@gmail.com wrote:
From: Vitor Soares vitor.soares@toradex.com
During the probe, the genpd power_dev is added to the dpm_list after blk_ctrl due to its parent/child relationship. Making the blk_ctrl suspend after and resume before the genpd power_dev.
As a consequence, the system hangs when resuming the VPU due to the power domain dependency.
To ensure the proper suspend/resume order, add a device link betweem blk_ctrl and genpd power_dev. It guarantees genpd power_dev is suspended after and resumed before blk-ctrl.
Before discussing $subject patch, would you mind explaining to me why imx8m-blk-ctrl needs to use the ->suspend() callback at all?
Looking closer at that code (imx8m_blk_ctrl_suspend()), it calls pm_runtime_get_sync() for devices to power on "everything". Why isn't that managed by the consumer drivers (on a case by case basis) that are managing the devices that are attached to the genpds instead?
Kind regards Uffe
Cc: stable@vger.kernel.org Closes: https://lore.kernel.org/all/fccbb040330a706a4f7b34875db1d896a0bf81c8.camel@g... Link: https://lore.kernel.org/all/20240409085802.290439-1-ivitro@gmail.com/ Fixes: 2684ac05a8c4 ("soc: imx: add i.MX8M blk-ctrl driver") Suggested-by: Lucas Stach l.stach@pengutronix.de Signed-off-by: Vitor Soares vitor.soares@toradex.com
This is a new patch, but is a follow-up of: https://lore.kernel.org/all/20240409085802.290439-1-ivitro@gmail.com/
As suggested by Lucas, we are addressing this PM issue in the imx8m-blk-ctrl driver instead of in the imx8mm.dtsi.
drivers/pmdomain/imx/imx8m-blk-ctrl.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)
diff --git a/drivers/pmdomain/imx/imx8m-blk-ctrl.c b/drivers/pmdomain/imx/imx8m-blk-ctrl.c index ca942d7929c2..cd0d2296080d 100644 --- a/drivers/pmdomain/imx/imx8m-blk-ctrl.c +++ b/drivers/pmdomain/imx/imx8m-blk-ctrl.c @@ -283,6 +283,20 @@ static int imx8m_blk_ctrl_probe(struct platform_device *pdev) goto cleanup_pds; }
/** Enforce suspend/resume ordering by making genpd power_dev a* provider of blk-ctrl. Genpd power_dev is suspended after and* resumed before blk-ctrl.*/if (!device_link_add(dev, domain->power_dev, DL_FLAG_STATELESS)) {ret = -EINVAL;dev_err_probe(dev, ret,"failed to link to %s\n", data->name);pm_genpd_remove(&domain->genpd);dev_pm_domain_detach(domain->power_dev, true);goto cleanup_pds;}/* * We use runtime PM to trigger power on/off of the upstream GPC * domain, as a strict hierarchical parent/child power domain@@ -324,6 +338,7 @@ static int imx8m_blk_ctrl_probe(struct platform_device *pdev) of_genpd_del_provider(dev->of_node); cleanup_pds: for (i--; i >= 0; i--) {
device_link_remove(dev, bc->domains[i].power_dev); pm_genpd_remove(&bc->domains[i].genpd); dev_pm_domain_detach(bc->domains[i].power_dev, true); }@@ -343,6 +358,7 @@ static void imx8m_blk_ctrl_remove(struct platform_device *pdev) for (i = 0; bc->onecell_data.num_domains; i++) { struct imx8m_blk_ctrl_domain *domain = &bc->domains[i];
device_link_remove(&pdev->dev, domain->power_dev); pm_genpd_remove(&domain->genpd); dev_pm_domain_detach(domain->power_dev, true); }-- 2.34.1
On Fri, 2024-05-10 at 11:34 +0200, Ulf Hansson wrote:
On Thu, 18 Apr 2024 at 17:52, Vitor Soares ivitro@gmail.com wrote:
From: Vitor Soares vitor.soares@toradex.com
During the probe, the genpd power_dev is added to the dpm_list after blk_ctrl due to its parent/child relationship. Making the blk_ctrl suspend after and resume before the genpd power_dev.
As a consequence, the system hangs when resuming the VPU due to the power domain dependency.
To ensure the proper suspend/resume order, add a device link betweem blk_ctrl and genpd power_dev. It guarantees genpd power_dev is suspended after and resumed before blk-ctrl.
Before discussing $subject patch, would you mind explaining to me why imx8m-blk-ctrl needs to use the ->suspend() callback at all?
Looking closer at that code (imx8m_blk_ctrl_suspend()), it calls pm_runtime_get_sync() for devices to power on "everything". Why isn't that managed by the consumer drivers (on a case by case basis) that are managing the devices that are attached to the genpds instead?
Kind regards Uffe
Hi Lucas, you know the driver architecture better than I do. Would you mind addressing Ulf concerns?
In addition to that, I would say that given that this is a bug fix, it would be nice to have it merged. Having a buggy driver in the kernel is not solving this kind of architectural question.
Best regards, Vitor Soares
Cc: stable@vger.kernel.org Closes: https://lore.kernel.org/all/fccbb040330a706a4f7b34875db1d896a0bf81c8.camel@g... Link: https://lore.kernel.org/all/20240409085802.290439-1-ivitro@gmail.com/ Fixes: 2684ac05a8c4 ("soc: imx: add i.MX8M blk-ctrl driver") Suggested-by: Lucas Stach l.stach@pengutronix.de Signed-off-by: Vitor Soares vitor.soares@toradex.com
This is a new patch, but is a follow-up of: https://lore.kernel.org/all/20240409085802.290439-1-ivitro@gmail.com/
As suggested by Lucas, we are addressing this PM issue in the imx8m-blk-ctrl driver instead of in the imx8mm.dtsi.
drivers/pmdomain/imx/imx8m-blk-ctrl.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)
diff --git a/drivers/pmdomain/imx/imx8m-blk-ctrl.c b/drivers/pmdomain/imx/imx8m-blk-ctrl.c index ca942d7929c2..cd0d2296080d 100644 --- a/drivers/pmdomain/imx/imx8m-blk-ctrl.c +++ b/drivers/pmdomain/imx/imx8m-blk-ctrl.c @@ -283,6 +283,20 @@ static int imx8m_blk_ctrl_probe(struct platform_device *pdev) goto cleanup_pds; }
+ /* + * Enforce suspend/resume ordering by making genpd power_dev a + * provider of blk-ctrl. Genpd power_dev is suspended after and + * resumed before blk-ctrl. + */ + if (!device_link_add(dev, domain->power_dev, DL_FLAG_STATELESS)) { + ret = -EINVAL; + dev_err_probe(dev, ret, + "failed to link to %s\n", data->name); + pm_genpd_remove(&domain->genpd); + dev_pm_domain_detach(domain->power_dev, true); + goto cleanup_pds; + }
/* * We use runtime PM to trigger power on/off of the upstream GPC * domain, as a strict hierarchical parent/child power domain @@ -324,6 +338,7 @@ static int imx8m_blk_ctrl_probe(struct platform_device *pdev) of_genpd_del_provider(dev->of_node); cleanup_pds: for (i--; i >= 0; i--) { + device_link_remove(dev, bc->domains[i].power_dev); pm_genpd_remove(&bc->domains[i].genpd); dev_pm_domain_detach(bc->domains[i].power_dev, true); } @@ -343,6 +358,7 @@ static void imx8m_blk_ctrl_remove(struct platform_device *pdev) for (i = 0; bc->onecell_data.num_domains; i++) { struct imx8m_blk_ctrl_domain *domain = &bc->domains[i];
+ device_link_remove(&pdev->dev, domain->power_dev); pm_genpd_remove(&domain->genpd); dev_pm_domain_detach(domain->power_dev, true); } -- 2.34.1
linux-stable-mirror@lists.linaro.org
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Adam Ford -
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Markus Elfring -
Ulf Hansson -
Vitor Soares