diff mbox series

[2/2] iommu/riscv: support HPM and interrupt handling

Message ID 20250115030306.29735-3-zong.li@sifive.com (mailing list archive)
State New
Headers show
Series RISC-V IOMMU HPM support | expand

Checks

Context Check Description
conchuod/vmtest-for-next-PR fail PR summary
conchuod/patch-2-test-1 success .github/scripts/patches/tests/build_rv32_defconfig.sh took 104.17s
conchuod/patch-2-test-2 success .github/scripts/patches/tests/build_rv64_clang_allmodconfig.sh took 1048.56s
conchuod/patch-2-test-3 success .github/scripts/patches/tests/build_rv64_gcc_allmodconfig.sh took 1233.41s
conchuod/patch-2-test-4 success .github/scripts/patches/tests/build_rv64_nommu_k210_defconfig.sh took 16.09s
conchuod/patch-2-test-5 success .github/scripts/patches/tests/build_rv64_nommu_virt_defconfig.sh took 17.77s
conchuod/patch-2-test-6 success .github/scripts/patches/tests/checkpatch.sh took 0.44s
conchuod/patch-2-test-7 success .github/scripts/patches/tests/dtb_warn_rv64.sh took 36.44s
conchuod/patch-2-test-8 success .github/scripts/patches/tests/header_inline.sh took 0.00s
conchuod/patch-2-test-9 success .github/scripts/patches/tests/kdoc.sh took 0.49s
conchuod/patch-2-test-10 success .github/scripts/patches/tests/module_param.sh took 0.01s
conchuod/patch-2-test-11 success .github/scripts/patches/tests/verify_fixes.sh took 0.00s
conchuod/patch-2-test-12 success .github/scripts/patches/tests/verify_signedoff.sh took 0.02s

Commit Message

Zong Li Jan. 15, 2025, 3:03 a.m. UTC
Initialize the PMU and uninitialize it when driver is removed.
Interrupt handling is also implemented, and the handler needs
to be a primary handler instead of a threaded function because
pt_regs is empty when threading the IRQ. However, pt_regs is
required by perf_event_overflow.

Signed-off-by: Zong Li <zong.li@sifive.com>
Tested-by: Xu Lu <luxu.kernel@bytedance.com>
---
 drivers/iommu/riscv/iommu.c | 65 +++++++++++++++++++++++++++++++++++++
 1 file changed, 65 insertions(+)

Comments

Andrew Jones Jan. 15, 2025, 9:44 a.m. UTC | #1
On Wed, Jan 15, 2025 at 11:03:06AM +0800, Zong Li wrote:
> Initialize the PMU and uninitialize it when driver is removed.
> Interrupt handling is also implemented, and the handler needs
> to be a primary handler instead of a threaded function because
> pt_regs is empty when threading the IRQ. However, pt_regs is
> required by perf_event_overflow.
> 
> Signed-off-by: Zong Li <zong.li@sifive.com>
> Tested-by: Xu Lu <luxu.kernel@bytedance.com>
> ---
>  drivers/iommu/riscv/iommu.c | 65 +++++++++++++++++++++++++++++++++++++
>  1 file changed, 65 insertions(+)
> 
> diff --git a/drivers/iommu/riscv/iommu.c b/drivers/iommu/riscv/iommu.c
> index 8a05def774bd..20ae90471484 100644
> --- a/drivers/iommu/riscv/iommu.c
> +++ b/drivers/iommu/riscv/iommu.c
> @@ -552,6 +552,62 @@ static irqreturn_t riscv_iommu_fltq_process(int irq, void *data)
>  	return IRQ_HANDLED;
>  }
>  
> +/*
> + * IOMMU Hardware performance monitor
> + */
> +
> +/* HPM interrupt primary handler */
> +static irqreturn_t riscv_iommu_hpm_irq_handler(int irq, void *dev_id)
> +{
> +	struct riscv_iommu_device *iommu = (struct riscv_iommu_device *)dev_id;
> +
> +	/* Clear performance monitoring interrupt pending */
> +	riscv_iommu_writel(iommu, RISCV_IOMMU_REG_IPSR, RISCV_IOMMU_IPSR_PMIP);
> +
> +	/* Process pmu irq */
> +	riscv_iommu_pmu_handle_irq(&iommu->pmu);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +/* HPM initialization */
> +static int riscv_iommu_hpm_enable(struct riscv_iommu_device *iommu)
> +{
> +	int rc;
> +
> +	if (!(iommu->caps & RISCV_IOMMU_CAPABILITIES_HPM))
> +		return 0;
> +
> +	/*
> +	 * pt_regs is empty when threading the IRQ, but pt_regs is necessary
> +	 * by perf_event_overflow. Use primary handler instead of thread
> +	 * function for PM IRQ.
> +	 *
> +	 * Set the IRQF_ONESHOT flag because this IRQ might be shared with
> +	 * other threaded IRQs by other queues.
> +	 */
> +	rc = devm_request_irq(iommu->dev,
> +			      iommu->irqs[riscv_iommu_queue_vec(iommu, RISCV_IOMMU_IPSR_PMIP)],
> +			      riscv_iommu_hpm_irq_handler, IRQF_ONESHOT | IRQF_SHARED, NULL, iommu);
> +	if (rc)
> +		return rc;
> +
> +	return riscv_iommu_pmu_init(&iommu->pmu, iommu->reg, dev_name(iommu->dev));
> +}
> +
> +/* HPM uninitialization */
> +static void riscv_iommu_hpm_disable(struct riscv_iommu_device *iommu)
> +{
> +	if (!(iommu->caps & RISCV_IOMMU_CAPABILITIES_HPM))
> +		return;
> +
> +	devm_free_irq(iommu->dev,
> +		      iommu->irqs[riscv_iommu_queue_vec(iommu, RISCV_IOMMU_IPSR_PMIP)],
> +		      iommu);
> +
> +	riscv_iommu_pmu_uninit(&iommu->pmu);
> +}
> +
>  /* Lookup and initialize device context info structure. */
>  static struct riscv_iommu_dc *riscv_iommu_get_dc(struct riscv_iommu_device *iommu,
>  						 unsigned int devid)
> @@ -1596,6 +1652,9 @@ void riscv_iommu_remove(struct riscv_iommu_device *iommu)
>  	riscv_iommu_iodir_set_mode(iommu, RISCV_IOMMU_DDTP_IOMMU_MODE_OFF);
>  	riscv_iommu_queue_disable(&iommu->cmdq);
>  	riscv_iommu_queue_disable(&iommu->fltq);
> +
> +	if (iommu->caps & RISCV_IOMMU_CAPABILITIES_HPM)
> +		riscv_iommu_pmu_uninit(&iommu->pmu);

This should be

   riscv_iommu_hpm_disable(iommu);

as the cover letter said it would be.

>  }
>  
>  int riscv_iommu_init(struct riscv_iommu_device *iommu)
> @@ -1635,6 +1694,10 @@ int riscv_iommu_init(struct riscv_iommu_device *iommu)
>  	if (rc)
>  		goto err_queue_disable;
>  
> +	rc = riscv_iommu_hpm_enable(iommu);
> +	if (rc)
> +		goto err_hpm_disable;

This should be

  goto err_iodir_off;

And the next goto (under sysfs add) should be

  goto err_hpm_disable;

> +
>  	rc = iommu_device_sysfs_add(&iommu->iommu, NULL, NULL, "riscv-iommu@%s",
>  				    dev_name(iommu->dev));
>  	if (rc) {
> @@ -1653,6 +1716,8 @@ int riscv_iommu_init(struct riscv_iommu_device *iommu)
>  err_remove_sysfs:
>  	iommu_device_sysfs_remove(&iommu->iommu);
>  err_iodir_off:
> +	riscv_iommu_hpm_disable(iommu);
> +err_hpm_disable:
>  	riscv_iommu_iodir_set_mode(iommu, RISCV_IOMMU_DDTP_IOMMU_MODE_OFF);
>  err_queue_disable:
>  	riscv_iommu_queue_disable(&iommu->fltq);

This should be

 err_remove_sysfs:
   ...
 err_hpm_disable:
   ...
 err_iodir_off:
   ...
 err_queue_disable:
   ...


Thanks,
drew
diff mbox series

Patch

diff --git a/drivers/iommu/riscv/iommu.c b/drivers/iommu/riscv/iommu.c
index 8a05def774bd..20ae90471484 100644
--- a/drivers/iommu/riscv/iommu.c
+++ b/drivers/iommu/riscv/iommu.c
@@ -552,6 +552,62 @@  static irqreturn_t riscv_iommu_fltq_process(int irq, void *data)
 	return IRQ_HANDLED;
 }
 
+/*
+ * IOMMU Hardware performance monitor
+ */
+
+/* HPM interrupt primary handler */
+static irqreturn_t riscv_iommu_hpm_irq_handler(int irq, void *dev_id)
+{
+	struct riscv_iommu_device *iommu = (struct riscv_iommu_device *)dev_id;
+
+	/* Clear performance monitoring interrupt pending */
+	riscv_iommu_writel(iommu, RISCV_IOMMU_REG_IPSR, RISCV_IOMMU_IPSR_PMIP);
+
+	/* Process pmu irq */
+	riscv_iommu_pmu_handle_irq(&iommu->pmu);
+
+	return IRQ_HANDLED;
+}
+
+/* HPM initialization */
+static int riscv_iommu_hpm_enable(struct riscv_iommu_device *iommu)
+{
+	int rc;
+
+	if (!(iommu->caps & RISCV_IOMMU_CAPABILITIES_HPM))
+		return 0;
+
+	/*
+	 * pt_regs is empty when threading the IRQ, but pt_regs is necessary
+	 * by perf_event_overflow. Use primary handler instead of thread
+	 * function for PM IRQ.
+	 *
+	 * Set the IRQF_ONESHOT flag because this IRQ might be shared with
+	 * other threaded IRQs by other queues.
+	 */
+	rc = devm_request_irq(iommu->dev,
+			      iommu->irqs[riscv_iommu_queue_vec(iommu, RISCV_IOMMU_IPSR_PMIP)],
+			      riscv_iommu_hpm_irq_handler, IRQF_ONESHOT | IRQF_SHARED, NULL, iommu);
+	if (rc)
+		return rc;
+
+	return riscv_iommu_pmu_init(&iommu->pmu, iommu->reg, dev_name(iommu->dev));
+}
+
+/* HPM uninitialization */
+static void riscv_iommu_hpm_disable(struct riscv_iommu_device *iommu)
+{
+	if (!(iommu->caps & RISCV_IOMMU_CAPABILITIES_HPM))
+		return;
+
+	devm_free_irq(iommu->dev,
+		      iommu->irqs[riscv_iommu_queue_vec(iommu, RISCV_IOMMU_IPSR_PMIP)],
+		      iommu);
+
+	riscv_iommu_pmu_uninit(&iommu->pmu);
+}
+
 /* Lookup and initialize device context info structure. */
 static struct riscv_iommu_dc *riscv_iommu_get_dc(struct riscv_iommu_device *iommu,
 						 unsigned int devid)
@@ -1596,6 +1652,9 @@  void riscv_iommu_remove(struct riscv_iommu_device *iommu)
 	riscv_iommu_iodir_set_mode(iommu, RISCV_IOMMU_DDTP_IOMMU_MODE_OFF);
 	riscv_iommu_queue_disable(&iommu->cmdq);
 	riscv_iommu_queue_disable(&iommu->fltq);
+
+	if (iommu->caps & RISCV_IOMMU_CAPABILITIES_HPM)
+		riscv_iommu_pmu_uninit(&iommu->pmu);
 }
 
 int riscv_iommu_init(struct riscv_iommu_device *iommu)
@@ -1635,6 +1694,10 @@  int riscv_iommu_init(struct riscv_iommu_device *iommu)
 	if (rc)
 		goto err_queue_disable;
 
+	rc = riscv_iommu_hpm_enable(iommu);
+	if (rc)
+		goto err_hpm_disable;
+
 	rc = iommu_device_sysfs_add(&iommu->iommu, NULL, NULL, "riscv-iommu@%s",
 				    dev_name(iommu->dev));
 	if (rc) {
@@ -1653,6 +1716,8 @@  int riscv_iommu_init(struct riscv_iommu_device *iommu)
 err_remove_sysfs:
 	iommu_device_sysfs_remove(&iommu->iommu);
 err_iodir_off:
+	riscv_iommu_hpm_disable(iommu);
+err_hpm_disable:
 	riscv_iommu_iodir_set_mode(iommu, RISCV_IOMMU_DDTP_IOMMU_MODE_OFF);
 err_queue_disable:
 	riscv_iommu_queue_disable(&iommu->fltq);