0093-iommu-arm-smmu-v3-Add-suspend-and-resume-support.patch

From 44e13387d11e4e0b525067294d36e6e3775137a4 Mon Sep 17 00:00:00 2001
From: Bixuan Cui <cuibixuan@huawei.com>
Date: Mon, 17 Jun 2024 19:33:08 +0800
Subject: [PATCH 093/150] iommu/arm-smmu-v3: Add suspend and resume support

Add suspend and resume support for smmuv3. The smmu is stopped when
suspending and started when resuming.

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.

Closes: https://gitee.com/openeuler/kernel/issues/I4DZ7Q

Signed-off-by: Bixuan Cui <cuibixuan@huawei.com>
Signed-off-by: Zhou Guanghui <zhouguanghui1@huawei.com>
Reviewed-by: Hanjun Guo <guohanjun@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Wang Xu <wangxu@phytium.com.cn>
Signed-off-by: Li Mingzhe <limingzhe1839@phytium.com.cn>
Signed-off-by: Chen Baozi <chenbaozi@phytium.com.cn>
Change-Id: I8e86de9ced49fff1206519739f730cc20d2c4d66
Signed-off-by: Andrew Powers-Holmes <aholmes@omnom.net>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 97 ++++++++++++++++++---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h |  1 +
 2 files changed, 88 insertions(+), 10 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 68b81f9c2f4b..8ef0e1a766b1 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -3154,6 +3154,13 @@ static void arm_smmu_write_msi_msg(struct msi_desc *desc, struct msi_msg *msg)
 	doorbell = (((u64)msg->address_hi) << 32) | msg->address_lo;
 	doorbell &= MSI_CFG0_ADDR_MASK;
 
+#ifdef CONFIG_PM_SLEEP
+	/* Saves the msg (base addr of msi irq) and restores it during resume */
+	desc->msg.address_lo = msg->address_lo;
+	desc->msg.address_hi = msg->address_hi;
+	desc->msg.data = msg->data;
+#endif
+
 	writeq_relaxed(doorbell, smmu->base + cfg[0]);
 	writel_relaxed(msg->data, smmu->base + cfg[1]);
 	writel_relaxed(ARM_SMMU_MEMATTR_DEVICE_nGnRE, smmu->base + cfg[2]);
@@ -3196,11 +3203,53 @@ static void arm_smmu_setup_msis(struct arm_smmu_device *smmu)
 	devm_add_action_or_reset(dev, arm_smmu_free_msis, dev);
 }
 
-static void arm_smmu_setup_unique_irqs(struct arm_smmu_device *smmu)
+#ifdef CONFIG_PM_SLEEP
+static void arm_smmu_resume_msis(struct arm_smmu_device *smmu)
+{
+	struct msi_desc *desc;
+	struct device *dev = smmu->dev;
+
+	if (!dev->msi.domain)
+		return;
+
+	msi_for_each_desc(desc, dev, MSI_DESC_ASSOCIATED) {
+		switch (desc->msi_index) {
+		case EVTQ_MSI_INDEX:
+		case GERROR_MSI_INDEX:
+		case PRIQ_MSI_INDEX: {
+			phys_addr_t *cfg = arm_smmu_msi_cfg[desc->msi_index];
+			struct msi_msg *msg = &desc->msg;
+			phys_addr_t doorbell = (((u64)msg->address_hi) << 32) | msg->address_lo;
+
+			doorbell &= MSI_CFG0_ADDR_MASK;
+			writeq_relaxed(doorbell, smmu->base + cfg[0]);
+			writel_relaxed(msg->data, smmu->base + cfg[1]);
+			writel_relaxed(ARM_SMMU_MEMATTR_DEVICE_nGnRE,
+							smmu->base + cfg[2]);
+			break;
+		}
+		default:
+				break;
+		}
+	}
+}
+#else
+static void arm_smmu_resume_msis(struct arm_smmu_device *smmu)
+{
+}
+#endif
+
+static void arm_smmu_setup_unique_irqs(struct arm_smmu_device *smmu, bool resume)
 {
 	int irq, ret;
 
-	arm_smmu_setup_msis(smmu);
+	if (!resume)
+		arm_smmu_setup_msis(smmu);
+	else {
+		/* The irq doesn't need to be re-requested during resume */
+		arm_smmu_resume_msis(smmu);
+		return;
+	}
 
 	/* Request interrupt lines */
 	irq = smmu->evtq.q.irq;
@@ -3242,7 +3291,7 @@ static void arm_smmu_setup_unique_irqs(struct arm_smmu_device *smmu)
 	}
 }
 
-static int arm_smmu_setup_irqs(struct arm_smmu_device *smmu)
+static int arm_smmu_setup_irqs(struct arm_smmu_device *smmu, bool resume)
 {
 	int ret, irq;
 	u32 irqen_flags = IRQ_CTRL_EVTQ_IRQEN | IRQ_CTRL_GERROR_IRQEN;
@@ -3269,7 +3318,7 @@ static int arm_smmu_setup_irqs(struct arm_smmu_device *smmu)
 		if (ret < 0)
 			dev_warn(smmu->dev, "failed to enable combined irq\n");
 	} else
-		arm_smmu_setup_unique_irqs(smmu);
+		arm_smmu_setup_unique_irqs(smmu, resume);
 
 	if (smmu->features & ARM_SMMU_FEAT_PRI)
 		irqen_flags |= IRQ_CTRL_PRIQ_IRQEN;
@@ -3294,7 +3343,7 @@ 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, bool resume)
 {
 	int ret;
 	u32 reg, enables;
@@ -3402,7 +3451,7 @@ static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass)
 		}
 	}
 
-	ret = arm_smmu_setup_irqs(smmu);
+	ret = arm_smmu_setup_irqs(smmu, resume);
 	if (ret) {
 		dev_err(smmu->dev, "failed to setup irqs\n");
 		return ret;
@@ -3412,7 +3461,7 @@ 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);
@@ -3797,6 +3846,24 @@ static void arm_smmu_rmr_install_bypass_ste(struct arm_smmu_device *smmu)
 	iort_put_rmr_sids(dev_fwnode(smmu->dev), &rmr_list);
 }
 
+#ifdef CONFIG_PM_SLEEP
+static int arm_smmu_suspend(struct device *dev)
+{
+	/*
+	 * The smmu is powered off and related registers are automatically
+	 * cleared when suspend. No need to do anything.
+	 */
+	return 0;
+}
+static int arm_smmu_resume(struct device *dev)
+{
+	struct arm_smmu_device *smmu = dev_get_drvdata(dev);
+
+	arm_smmu_device_reset(smmu, true);
+	return 0;
+}
+#endif
+
 static int arm_smmu_device_probe(struct platform_device *pdev)
 {
 	int irq, ret;
@@ -3804,7 +3871,6 @@ 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)
@@ -3820,7 +3886,7 @@ 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);
@@ -3884,7 +3950,7 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
 	arm_smmu_rmr_install_bypass_ste(smmu);
 
 	/* Reset the device */
-	ret = arm_smmu_device_reset(smmu, bypass);
+	ret = arm_smmu_device_reset(smmu, false);
 	if (ret)
 		return ret;
 
@@ -3934,10 +4000,21 @@ static void arm_smmu_driver_unregister(struct platform_driver *drv)
 	platform_driver_unregister(drv);
 }
 
+#ifdef CONFIG_PM_SLEEP
+static const struct dev_pm_ops arm_smmu_pm_ops = {
+	.suspend = arm_smmu_suspend,
+	.resume = arm_smmu_resume,
+};
+#define ARM_SMMU_PM_OPS                (&arm_smmu_pm_ops)
+#else
+#define ARM_SMMU_PM_OPS                NULL
+#endif
+
 static struct platform_driver arm_smmu_driver = {
 	.driver	= {
 		.name			= "arm-smmu-v3",
 		.of_match_table		= arm_smmu_of_match,
+		.pm			= ARM_SMMU_PM_OPS,
 		.suppress_bind_attrs	= true,
 	},
 	.probe	= arm_smmu_device_probe,
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 9915850dd4db..9cb3864b1114 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -682,6 +682,7 @@ struct arm_smmu_device {
 
 	struct rb_root			streams;
 	struct mutex			streams_mutex;
+	bool				bypass;
 };
 
 struct arm_smmu_stream {
-- 
2.47.0