Re: [PATCH v9 09/12] pci-epf-test/pci_endpoint_test: Add MSI-X support

From: Kishon Vijay Abraham I
Date: Fri Jul 13 2018 - 04:09:19 EST




On Monday 09 July 2018 11:12 PM, Gustavo Pimentel wrote:
> Add MSI-X support and update driver documentation accordingly.
>
> Signed-off-by: Gustavo Pimentel <gustavo.pimentel@xxxxxxxxxxxx>

Acked-by: Kishon Vijay Abraham I <kishon@xxxxxx>
> ---
> Change v2->v3:
> - New patch file created base on the previous patch
> "misc: pci_endpoint_test: Add MSI-X support" patch file following
> Kishon's suggestion.
> Change v3->v4:
> - Rebased to Lorenzo's master branch v4.18-rc1.
> Change v4->v5:
> - Nothing changed, just to follow the patch set version.
> Change v5->v6:
> - Moved PCITEST_MSIX ioctl entry from patch #10 to here.
> - Documented ioctl parameter type associated to
> drivers/misc/pci_endpoint_test.c driver.
> Change v6->v7:
> - Updated documentation.
> - Added flag that enables or not the MSI-X on the EP features.
> Change v7->v8:
> - Re-sending the patch series.
> Change v8->v9:
> - Moving the EPC_FEATURE_MSIX_AVAILABLE feature set from the
> dw_pcie_ep_init() to dw_plat_pcie_ep_init().
>
> Documentation/PCI/endpoint/pci-test-function.txt | 2 +-
> Documentation/ioctl/ioctl-number.txt | 1 +
> Documentation/misc-devices/pci-endpoint-test.txt | 3 +++
> drivers/misc/pci_endpoint_test.c | 29 ++++++++++++++++-------
> drivers/pci/controller/dwc/pcie-designware-plat.c | 1 +
> drivers/pci/endpoint/functions/pci-epf-test.c | 29 +++++++++++++++++++++--
> include/linux/pci-epc.h | 1 +
> include/uapi/linux/pcitest.h | 1 +
> 8 files changed, 56 insertions(+), 11 deletions(-)
>
> diff --git a/Documentation/PCI/endpoint/pci-test-function.txt b/Documentation/PCI/endpoint/pci-test-function.txt
> index 7ee2361..b1cbff3 100644
> --- a/Documentation/PCI/endpoint/pci-test-function.txt
> +++ b/Documentation/PCI/endpoint/pci-test-function.txt
> @@ -34,7 +34,7 @@ that the endpoint device must perform.
> Bitfield Description:
> Bit 0 : raise legacy IRQ
> Bit 1 : raise MSI IRQ
> - Bit 2 : raise MSI-X IRQ (reserved for future implementation)
> + Bit 2 : raise MSI-X IRQ
> Bit 3 : read command (read data from RC buffer)
> Bit 4 : write command (write data to RC buffer)
> Bit 5 : copy command (copy data from one RC buffer to another
> diff --git a/Documentation/ioctl/ioctl-number.txt b/Documentation/ioctl/ioctl-number.txt
> index 480c860..65259d4 100644
> --- a/Documentation/ioctl/ioctl-number.txt
> +++ b/Documentation/ioctl/ioctl-number.txt
> @@ -166,6 +166,7 @@ Code Seq#(hex) Include File Comments
> 'P' all linux/soundcard.h conflict!
> 'P' 60-6F sound/sscape_ioctl.h conflict!
> 'P' 00-0F drivers/usb/class/usblp.c conflict!
> +'P' 01-07 drivers/misc/pci_endpoint_test.c conflict!
> 'Q' all linux/soundcard.h
> 'R' 00-1F linux/random.h conflict!
> 'R' 01 linux/rfkill.h conflict!
> diff --git a/Documentation/misc-devices/pci-endpoint-test.txt b/Documentation/misc-devices/pci-endpoint-test.txt
> index 4ebc359..fdfa0f6 100644
> --- a/Documentation/misc-devices/pci-endpoint-test.txt
> +++ b/Documentation/misc-devices/pci-endpoint-test.txt
> @@ -10,6 +10,7 @@ The PCI driver for the test device performs the following tests
> *) verifying addresses programmed in BAR
> *) raise legacy IRQ
> *) raise MSI IRQ
> + *) raise MSI-X IRQ
> *) read data
> *) write data
> *) copy data
> @@ -25,6 +26,8 @@ ioctl
> PCITEST_LEGACY_IRQ: Tests legacy IRQ
> PCITEST_MSI: Tests message signalled interrupts. The MSI number
> to be tested should be passed as argument.
> + PCITEST_MSIX: Tests message signalled interrupts. The MSI-X number
> + to be tested should be passed as argument.
> PCITEST_WRITE: Perform write tests. The size of the buffer should be passed
> as argument.
> PCITEST_READ: Perform read tests. The size of the buffer should be passed
> diff --git a/drivers/misc/pci_endpoint_test.c b/drivers/misc/pci_endpoint_test.c
> index 349794c..f4fef10 100644
> --- a/drivers/misc/pci_endpoint_test.c
> +++ b/drivers/misc/pci_endpoint_test.c
> @@ -39,13 +39,14 @@
>
> #define IRQ_TYPE_LEGACY 0
> #define IRQ_TYPE_MSI 1
> +#define IRQ_TYPE_MSIX 2
>
> #define PCI_ENDPOINT_TEST_MAGIC 0x0
>
> #define PCI_ENDPOINT_TEST_COMMAND 0x4
> #define COMMAND_RAISE_LEGACY_IRQ BIT(0)
> #define COMMAND_RAISE_MSI_IRQ BIT(1)
> -/* BIT(2) is reserved for raising MSI-X IRQ command */
> +#define COMMAND_RAISE_MSIX_IRQ BIT(2)
> #define COMMAND_READ BIT(3)
> #define COMMAND_WRITE BIT(4)
> #define COMMAND_COPY BIT(5)
> @@ -84,7 +85,7 @@ MODULE_PARM_DESC(no_msi, "Disable MSI interrupt in pci_endpoint_test");
>
> static int irq_type = IRQ_TYPE_MSI;
> module_param(irq_type, int, 0444);
> -MODULE_PARM_DESC(irq_type, "IRQ mode selection in pci_endpoint_test (0 - Legacy, 1 - MSI)");
> +MODULE_PARM_DESC(irq_type, "IRQ mode selection in pci_endpoint_test (0 - Legacy, 1 - MSI, 2 - MSI-X)");
>
> enum pci_barno {
> BAR_0,
> @@ -202,16 +203,18 @@ static bool pci_endpoint_test_legacy_irq(struct pci_endpoint_test *test)
> }
>
> static bool pci_endpoint_test_msi_irq(struct pci_endpoint_test *test,
> - u8 msi_num)
> + u16 msi_num, bool msix)
> {
> u32 val;
> struct pci_dev *pdev = test->pdev;
>
> pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_IRQ_TYPE,
> - IRQ_TYPE_MSI);
> + msix == false ? IRQ_TYPE_MSI :
> + IRQ_TYPE_MSIX);
> pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_IRQ_NUMBER, msi_num);
> pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_COMMAND,
> - COMMAND_RAISE_MSI_IRQ);
> + msix == false ? COMMAND_RAISE_MSI_IRQ :
> + COMMAND_RAISE_MSIX_IRQ);
> val = wait_for_completion_timeout(&test->irq_raised,
> msecs_to_jiffies(1000));
> if (!val)
> @@ -456,7 +459,8 @@ static long pci_endpoint_test_ioctl(struct file *file, unsigned int cmd,
> ret = pci_endpoint_test_legacy_irq(test);
> break;
> case PCITEST_MSI:
> - ret = pci_endpoint_test_msi_irq(test, arg);
> + case PCITEST_MSIX:
> + ret = pci_endpoint_test_msi_irq(test, arg, cmd == PCITEST_MSIX);
> break;
> case PCITEST_WRITE:
> ret = pci_endpoint_test_write(test, arg);
> @@ -542,6 +546,12 @@ static int pci_endpoint_test_probe(struct pci_dev *pdev,
> dev_err(dev, "Failed to get MSI interrupts\n");
> test->num_irqs = irq;
> break;
> + case IRQ_TYPE_MSIX:
> + irq = pci_alloc_irq_vectors(pdev, 1, 2048, PCI_IRQ_MSIX);
> + if (irq < 0)
> + dev_err(dev, "Failed to get MSI-X interrupts\n");
> + test->num_irqs = irq;
> + break;
> default:
> dev_err(dev, "Invalid IRQ type selected\n");
> }
> @@ -558,8 +568,9 @@ static int pci_endpoint_test_probe(struct pci_dev *pdev,
> pci_endpoint_test_irqhandler,
> IRQF_SHARED, DRV_MODULE_NAME, test);
> if (err)
> - dev_err(dev, "failed to request IRQ %d for MSI %d\n",
> - pci_irq_vector(pdev, i), i + 1);
> + dev_err(dev, "Failed to request IRQ %d for MSI%s %d\n",
> + pci_irq_vector(pdev, i),
> + irq_type == IRQ_TYPE_MSIX ? "-X" : "", i + 1);
> }
>
> for (bar = BAR_0; bar <= BAR_5; bar++) {
> @@ -625,6 +636,7 @@ static int pci_endpoint_test_probe(struct pci_dev *pdev,
>
> err_disable_msi:
> pci_disable_msi(pdev);
> + pci_disable_msix(pdev);
> pci_release_regions(pdev);
>
> err_disable_pdev:
> @@ -656,6 +668,7 @@ static void pci_endpoint_test_remove(struct pci_dev *pdev)
> for (i = 0; i < test->num_irqs; i++)
> devm_free_irq(&pdev->dev, pci_irq_vector(pdev, i), test);
> pci_disable_msi(pdev);
> + pci_disable_msix(pdev);
> pci_release_regions(pdev);
> pci_disable_device(pdev);
> }
> diff --git a/drivers/pci/controller/dwc/pcie-designware-plat.c b/drivers/pci/controller/dwc/pcie-designware-plat.c
> index 160714d..d2dd0c7 100644
> --- a/drivers/pci/controller/dwc/pcie-designware-plat.c
> +++ b/drivers/pci/controller/dwc/pcie-designware-plat.c
> @@ -77,6 +77,7 @@ static void dw_plat_pcie_ep_init(struct dw_pcie_ep *ep)
> dw_pcie_ep_reset_bar(pci, bar);
>
> epc->features |= EPC_FEATURE_NO_LINKUP_NOTIFIER;
> + epc->features |= EPC_FEATURE_MSIX_AVAILABLE;
> }
>
> static int dw_plat_pcie_ep_raise_irq(struct dw_pcie_ep *ep, u8 func_no,
> diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c
> index eb9cd00..123f58c 100644
> --- a/drivers/pci/endpoint/functions/pci-epf-test.c
> +++ b/drivers/pci/endpoint/functions/pci-epf-test.c
> @@ -20,10 +20,11 @@
>
> #define IRQ_TYPE_LEGACY 0
> #define IRQ_TYPE_MSI 1
> +#define IRQ_TYPE_MSIX 2
>
> #define COMMAND_RAISE_LEGACY_IRQ BIT(0)
> #define COMMAND_RAISE_MSI_IRQ BIT(1)
> -/* BIT(2) is reserved for raising MSI-X IRQ command */
> +#define COMMAND_RAISE_MSIX_IRQ BIT(2)
> #define COMMAND_READ BIT(3)
> #define COMMAND_WRITE BIT(4)
> #define COMMAND_COPY BIT(5)
> @@ -47,6 +48,7 @@ struct pci_epf_test {
> struct pci_epf *epf;
> enum pci_barno test_reg_bar;
> bool linkup_notifier;
> + bool msix_available;
> struct delayed_work cmd_handler;
> };
>
> @@ -266,6 +268,9 @@ static void pci_epf_test_raise_irq(struct pci_epf_test *epf_test, u8 irq_type,
> case IRQ_TYPE_MSI:
> pci_epc_raise_irq(epc, epf->func_no, PCI_EPC_IRQ_MSI, irq);
> break;
> + case IRQ_TYPE_MSIX:
> + pci_epc_raise_irq(epc, epf->func_no, PCI_EPC_IRQ_MSIX, irq);
> + break;
> default:
> dev_err(dev, "Failed to raise IRQ, unknown type\n");
> break;
> @@ -292,7 +297,7 @@ static void pci_epf_test_cmd_handler(struct work_struct *work)
> reg->command = 0;
> reg->status = 0;
>
> - if (reg->irq_type > IRQ_TYPE_MSI) {
> + if (reg->irq_type > IRQ_TYPE_MSIX) {
> dev_err(dev, "Failed to detect IRQ type\n");
> goto reset_handler;
> }
> @@ -346,6 +351,16 @@ static void pci_epf_test_cmd_handler(struct work_struct *work)
> goto reset_handler;
> }
>
> + if (command & COMMAND_RAISE_MSIX_IRQ) {
> + count = pci_epc_get_msix(epc, epf->func_no);
> + if (reg->irq_number > count || count <= 0)
> + goto reset_handler;
> + reg->status = STATUS_IRQ_RAISED;
> + pci_epc_raise_irq(epc, epf->func_no, PCI_EPC_IRQ_MSIX,
> + reg->irq_number);
> + goto reset_handler;
> + }
> +
> reset_handler:
> queue_delayed_work(kpcitest_workqueue, &epf_test->cmd_handler,
> msecs_to_jiffies(1));
> @@ -459,6 +474,8 @@ static int pci_epf_test_bind(struct pci_epf *epf)
> else
> epf_test->linkup_notifier = true;
>
> + epf_test->msix_available = epc->features & EPC_FEATURE_MSIX_AVAILABLE;
> +
> epf_test->test_reg_bar = EPC_FEATURE_GET_BAR(epc->features);
>
> ret = pci_epc_write_header(epc, epf->func_no, header);
> @@ -481,6 +498,14 @@ static int pci_epf_test_bind(struct pci_epf *epf)
> return ret;
> }
>
> + if (epf_test->msix_available) {
> + ret = pci_epc_set_msix(epc, epf->func_no, epf->msix_interrupts);
> + if (ret) {
> + dev_err(dev, "MSI-X configuration failed\n");
> + return ret;
> + }
> + }
> +
> if (!epf_test->linkup_notifier)
> queue_work(kpcitest_workqueue, &epf_test->cmd_handler.work);
>
> diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h
> index bb2395b..37dab81 100644
> --- a/include/linux/pci-epc.h
> +++ b/include/linux/pci-epc.h
> @@ -102,6 +102,7 @@ struct pci_epc {
>
> #define EPC_FEATURE_NO_LINKUP_NOTIFIER BIT(0)
> #define EPC_FEATURE_BAR_MASK (BIT(1) | BIT(2) | BIT(3))
> +#define EPC_FEATURE_MSIX_AVAILABLE BIT(4)
> #define EPC_FEATURE_SET_BAR(features, bar) \
> (features |= (EPC_FEATURE_BAR_MASK & (bar << 1)))
> #define EPC_FEATURE_GET_BAR(features) \
> diff --git a/include/uapi/linux/pcitest.h b/include/uapi/linux/pcitest.h
> index 953cf03..d746fb1 100644
> --- a/include/uapi/linux/pcitest.h
> +++ b/include/uapi/linux/pcitest.h
> @@ -16,5 +16,6 @@
> #define PCITEST_WRITE _IOW('P', 0x4, unsigned long)
> #define PCITEST_READ _IOW('P', 0x5, unsigned long)
> #define PCITEST_COPY _IOW('P', 0x6, unsigned long)
> +#define PCITEST_MSIX _IOW('P', 0x7, int)
>
> #endif /* __UAPI_LINUX_PCITEST_H */
>