* [PATCH -next v3 2/2] iommu/arm-smmu-v3: Add suspend and resume support
2021-08-28 6:39 [PATCH -next v3 1/2] platform-msi: Save the msg context to desc in platform_msi_write_msg() Bixuan Cui
@ 2021-08-28 6:39 ` Bixuan Cui
2021-09-14 9:08 ` [PATCH -next v3 1/2] platform-msi: Save the msg context to desc in platform_msi_write_msg() Greg KH
1 sibling, 0 replies; 3+ messages in thread
From: Bixuan Cui @ 2021-08-28 6:39 UTC (permalink / raw)
To: iommu, linux-kernel
Cc: will, gregkh, rafael, robin.murphy, joro, jean-philippe,
Jonathan.Cameron, thunder.leizhen, maz, linux-arm-kernel
Add suspend and resume support for arm-smmu-v3 by low-power mode.
When the smmu is suspended, it is powered off and the registers are
cleared. So saves the msi_msg context during msi interrupt initialization
of smmu. When resume happens it calls arm_smmu_device_reset() to restore
the registers.
Signed-off-by: Bixuan Cui <cuibixuan@huawei.com>
---
Changes in v3:
* Move the code of save msg context into msi platform (A new patch: "platform-msi: Save the msg context to desc in platform_msi_write_msg()").
* Add bypass member to the struct arm_smmu_device for per-SMMU bypass control(used by resume mode).
* Separate interrupt requests and register operations in arm_smmu_device_reset(). The arm_smmu_setup_irqs() is added to request interrupts and is called before arm_smmu_device_reset(). The arm_smmu_device_reset() resets irq registers (can also be called in resume mode).
Changes in v2:
* Using get_cached_msi_msg() instead of the descriptor to resume msi_msg
in arm_smmu_resume_msis();
* Move arm_smmu_resume_msis() from arm_smmu_setup_unique_irqs() into
arm_smmu_setup_irqs() and rename it to arm_smmu_resume_unique_irqs();
Call arm_smmu_setup_unique_irqs() to configure the IRQ during probe and
call arm_smmu_resume_unique_irqs() in resume mode to restore the IRQ
registers to make the code more reasonable.
* Call arm_smmu_device_disable() to disable smmu and clear CR0_SMMUEN on
suspend. Then the warning about CR0_SMMUEN being enabled can be cleared
on resume.
* Using SET_SYSTEM_SLEEP_PM_OPS();
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 99 +++++++++++++++++++--
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 1 +
2 files changed, 93 insertions(+), 7 deletions(-)
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index a388e318f86e..95a1c2689685 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -3282,6 +3282,61 @@ static int arm_smmu_setup_irqs(struct arm_smmu_device *smmu)
return 0;
}
+static void arm_smmu_reset_unique_irqs(struct arm_smmu_device *smmu)
+{
+ struct msi_desc *desc;
+ struct msi_msg msg;
+
+ desc = irq_get_msi_desc(smmu->evtq.q.irq);
+ if (desc) {
+ get_cached_msi_msg(smmu->evtq.q.irq, &msg);
+ arm_smmu_write_msi_msg(desc, &msg);
+ }
+
+ desc = irq_get_msi_desc(smmu->gerr_irq);
+ if (desc) {
+ get_cached_msi_msg(smmu->gerr_irq, &msg);
+ arm_smmu_write_msi_msg(desc, &msg);
+ }
+
+ if (smmu->features & ARM_SMMU_FEAT_PRI) {
+ desc = irq_get_msi_desc(smmu->priq.q.irq);
+ if (desc) {
+ get_cached_msi_msg(smmu->priq.q.irq, &msg);
+ arm_smmu_write_msi_msg(desc, &msg);
+ }
+ }
+}
+
+static int arm_smmu_reset_irqs(struct arm_smmu_device *smmu)
+{
+ int ret, irq;
+ u32 irqen_flags = IRQ_CTRL_EVTQ_IRQEN | IRQ_CTRL_GERROR_IRQEN;
+
+ /* Disable IRQs first */
+ ret = arm_smmu_write_reg_sync(smmu, 0, ARM_SMMU_IRQ_CTRL,
+ ARM_SMMU_IRQ_CTRLACK);
+ if (ret) {
+ dev_err(smmu->dev, "failed to disable irqs\n");
+ return ret;
+ }
+
+ irq = smmu->combined_irq;
+ if (!irq)
+ arm_smmu_reset_unique_irqs(smmu);
+
+ if (smmu->features & ARM_SMMU_FEAT_PRI)
+ irqen_flags |= IRQ_CTRL_PRIQ_IRQEN;
+
+ /* Enable interrupt generation on the SMMU */
+ ret = arm_smmu_write_reg_sync(smmu, irqen_flags,
+ ARM_SMMU_IRQ_CTRL, ARM_SMMU_IRQ_CTRLACK);
+ if (ret)
+ dev_warn(smmu->dev, "failed to reset irqs\n");
+
+ return 0;
+}
+
static int arm_smmu_device_disable(struct arm_smmu_device *smmu)
{
int ret;
@@ -3293,7 +3348,7 @@ static int arm_smmu_device_disable(struct arm_smmu_device *smmu)
return ret;
}
-static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass)
+static int arm_smmu_device_reset(struct arm_smmu_device *smmu)
{
int ret;
u32 reg, enables;
@@ -3401,9 +3456,9 @@ static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass)
}
}
- ret = arm_smmu_setup_irqs(smmu);
+ ret = arm_smmu_reset_irqs(smmu);
if (ret) {
- dev_err(smmu->dev, "failed to setup irqs\n");
+ dev_err(smmu->dev, "failed to reset irqs\n");
return ret;
}
@@ -3411,7 +3466,7 @@ static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass)
enables &= ~(CR0_EVTQEN | CR0_PRIQEN);
/* Enable the SMMU interface, or ensure bypass */
- if (!bypass || disable_bypass) {
+ if (!smmu->bypass || disable_bypass) {
enables |= CR0_SMMUEN;
} else {
ret = arm_smmu_update_gbpa(smmu, 0, GBPA_ABORT);
@@ -3758,6 +3813,25 @@ static void __iomem *arm_smmu_ioremap(struct device *dev, resource_size_t start,
return devm_ioremap_resource(dev, &res);
}
+static int __maybe_unused arm_smmu_suspend(struct device *dev)
+{
+ struct arm_smmu_device *smmu = dev_get_drvdata(dev);
+
+ /* disable smmu to clear CR0 */
+ arm_smmu_device_disable(smmu);
+
+ return 0;
+}
+
+static int __maybe_unused arm_smmu_resume(struct device *dev)
+{
+ struct arm_smmu_device *smmu = dev_get_drvdata(dev);
+
+ arm_smmu_device_reset(smmu);
+
+ return 0;
+}
+
static int arm_smmu_device_probe(struct platform_device *pdev)
{
int irq, ret;
@@ -3765,7 +3839,6 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
resource_size_t ioaddr;
struct arm_smmu_device *smmu;
struct device *dev = &pdev->dev;
- bool bypass;
smmu = devm_kzalloc(dev, sizeof(*smmu), GFP_KERNEL);
if (!smmu)
@@ -3781,7 +3854,7 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
}
/* Set bypass mode according to firmware probing result */
- bypass = !!ret;
+ smmu->bypass = !!ret;
/* Base address */
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -3839,8 +3912,15 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
/* Record our private device structure */
platform_set_drvdata(pdev, smmu);
+ /* Setup irqs */
+ ret = arm_smmu_setup_irqs(smmu);
+ if (ret) {
+ dev_err(smmu->dev, "failed to setup irqs\n");
+ return ret;
+ }
+
/* Reset the device */
- ret = arm_smmu_device_reset(smmu, bypass);
+ ret = arm_smmu_device_reset(smmu);
if (ret)
return ret;
@@ -3893,6 +3973,10 @@ static const struct of_device_id arm_smmu_of_match[] = {
};
MODULE_DEVICE_TABLE(of, arm_smmu_of_match);
+static const struct dev_pm_ops arm_smmu_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(arm_smmu_suspend, arm_smmu_resume)
+};
+
static void arm_smmu_driver_unregister(struct platform_driver *drv)
{
arm_smmu_sva_notifier_synchronize();
@@ -3904,6 +3988,7 @@ static struct platform_driver arm_smmu_driver = {
.name = "arm-smmu-v3",
.of_match_table = arm_smmu_of_match,
.suppress_bind_attrs = true,
+ .pm = &arm_smmu_pm_ops,
},
.probe = arm_smmu_device_probe,
.remove = arm_smmu_device_remove,
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
index 4cb136f07914..7777a7445bc2 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -675,6 +675,7 @@ struct arm_smmu_device {
struct rb_root streams;
struct mutex streams_mutex;
+ bool bypass;
};
struct arm_smmu_stream {
--
2.17.1
^ permalink raw reply related [flat|nested] 3+ messages in thread* Re: [PATCH -next v3 1/2] platform-msi: Save the msg context to desc in platform_msi_write_msg()
2021-08-28 6:39 [PATCH -next v3 1/2] platform-msi: Save the msg context to desc in platform_msi_write_msg() Bixuan Cui
2021-08-28 6:39 ` [PATCH -next v3 2/2] iommu/arm-smmu-v3: Add suspend and resume support Bixuan Cui
@ 2021-09-14 9:08 ` Greg KH
1 sibling, 0 replies; 3+ messages in thread
From: Greg KH @ 2021-09-14 9:08 UTC (permalink / raw)
To: Bixuan Cui
Cc: iommu, linux-kernel, will, rafael, robin.murphy, joro,
jean-philippe, Jonathan.Cameron, thunder.leizhen, maz,
linux-arm-kernel
On Sat, Aug 28, 2021 at 02:39:14PM +0800, Bixuan Cui wrote:
> Save the msg context to desc when the msi interrupt is requested.
> The drivers can use it in special scenarios(such as resume).
>
> Signed-off-by: Bixuan Cui <cuibixuan@huawei.com>
> ---
> drivers/base/platform-msi.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/base/platform-msi.c b/drivers/base/platform-msi.c
> index 3d6c8f9caf43..60962a224fcc 100644
> --- a/drivers/base/platform-msi.c
> +++ b/drivers/base/platform-msi.c
> @@ -90,6 +90,9 @@ static void platform_msi_write_msg(struct irq_data *data, struct msi_msg *msg)
>
> priv_data = desc->platform.msi_priv_data;
>
> + desc->msg.address_lo = msg->address_lo;
> + desc->msg.address_hi = msg->address_hi;
> + desc->msg.data = msg->data;
> priv_data->write_msg(desc, msg);
> }
>
> --
> 2.17.1
>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
^ permalink raw reply [flat|nested] 3+ messages in thread