On Wed, Apr 26, 2023 at 04:34:35PM -0400, Frank Li wrote: > Reused flags as capability register in pci_endpoint_test struct to > support older driver versions. Save capability flags to 'cap' field > of struct pci_endpoint_test to prevent reading non-existent address. > This won't work, please see below. > Add three registers: PCIE_ENDPOINT_TEST_DB_BAR, PCIE_ENDPOINT_TEST_DB_ADDR, > PCIE_ENDPOINT_TEST_DB_DATA. > > Write data from PCI_ENDPOINT_TEST_DB_DATA to address from > PCI_ENDPOINT_TEST_DB_ADDR to trigger doorbell and wait for remote > endpoint feedback. "wait for endpoint response" > > Signed-off-by: Frank Li <Frank.Li@xxxxxxx> > --- > drivers/misc/pci_endpoint_test.c | 41 ++++++++++++++++++++++++++++++++ > include/uapi/linux/pcitest.h | 1 + > 2 files changed, 42 insertions(+) > > diff --git a/drivers/misc/pci_endpoint_test.c b/drivers/misc/pci_endpoint_test.c > index ed4d0ef5e5c3..3320a3334594 100644 > --- a/drivers/misc/pci_endpoint_test.c > +++ b/drivers/misc/pci_endpoint_test.c > @@ -52,6 +52,7 @@ > #define STATUS_IRQ_RAISED BIT(6) > #define STATUS_SRC_ADDR_INVALID BIT(7) > #define STATUS_DST_ADDR_INVALID BIT(8) > +#define STATUS_DOORBELL_SUCCESS BIT(9) > > #define PCI_ENDPOINT_TEST_LOWER_SRC_ADDR 0x0c > #define PCI_ENDPOINT_TEST_UPPER_SRC_ADDR 0x10 > @@ -66,7 +67,12 @@ > #define PCI_ENDPOINT_TEST_IRQ_NUMBER 0x28 > > #define PCI_ENDPOINT_TEST_FLAGS 0x2c > +#define PCI_ENDPOINT_TEST_DB_BAR 0x30 > +#define PCI_ENDPOINT_TEST_DB_ADDR 0x34 > +#define PCI_ENDPOINT_TEST_DB_DATA 0x38 > + > #define FLAG_USE_DMA BIT(0) > +#define FLAG_SUPPORT_DOORBELL BIT(1) > > #define PCI_DEVICE_ID_TI_AM654 0xb00c > #define PCI_DEVICE_ID_TI_J7200 0xb00f > @@ -102,6 +108,7 @@ enum pci_barno { > BAR_3, > BAR_4, > BAR_5, > + NO_BAR = -1, > }; > > struct pci_endpoint_test { > @@ -118,6 +125,7 @@ struct pci_endpoint_test { > enum pci_barno test_reg_bar; > size_t alignment; > const char *name; > + u32 cap; > }; > > struct pci_endpoint_test_data { > @@ -713,6 +721,35 @@ static bool pci_endpoint_test_set_irq(struct pci_endpoint_test *test, > return false; > } > > +static bool pci_endpoint_test_doorbell(struct pci_endpoint_test *test) > +{ > + enum pci_barno bar; > + u32 data; > + u32 addr; > + > + if (!(test->cap & FLAG_SUPPORT_DOORBELL)) > + return false; > + > + bar = pci_endpoint_test_readl(test, PCI_ENDPOINT_TEST_DB_BAR); > + if (bar == NO_BAR) > + return false; Is this possible? > + > + data = pci_endpoint_test_readl(test, PCI_ENDPOINT_TEST_DB_DATA); > + addr = pci_endpoint_test_readl(test, PCI_ENDPOINT_TEST_DB_ADDR); > + bar = pci_endpoint_test_readl(test, PCI_ENDPOINT_TEST_DB_BAR); > + > + pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_STATUS, 0); > + pci_endpoint_test_bar_writel(test, bar, addr, data); >From patch 1, I understood that EP supports multiple doorbell. But you are not making use of it here? > + > + wait_for_completion(&test->irq_raised); > + No timeout? > + data = pci_endpoint_test_readl(test, PCI_ENDPOINT_TEST_STATUS); > + if (data & STATUS_DOORBELL_SUCCESS) Please use a separate variable. > + return true; > + > + return false; > +} > + > static long pci_endpoint_test_ioctl(struct file *file, unsigned int cmd, > unsigned long arg) > { > @@ -760,6 +797,9 @@ static long pci_endpoint_test_ioctl(struct file *file, unsigned int cmd, > case PCITEST_CLEAR_IRQ: > ret = pci_endpoint_test_clear_irq(test); > break; > + case PCITEST_DOORBELL: > + ret = pci_endpoint_test_doorbell(test); > + break; > } > > ret: > @@ -887,6 +927,7 @@ static int pci_endpoint_test_probe(struct pci_dev *pdev, > misc_device->parent = &pdev->dev; > misc_device->fops = &pci_endpoint_test_fops; > > + test->cap = pci_endpoint_test_readl(test, PCI_ENDPOINT_TEST_FLAGS); This register will be overwritten by this driver during (copy,read,write) tests. So this logic will not work. - Mani > err = misc_register(misc_device); > if (err) { > dev_err(dev, "Failed to register device\n"); > diff --git a/include/uapi/linux/pcitest.h b/include/uapi/linux/pcitest.h > index f9c1af8d141b..479ca1aa3ae0 100644 > --- a/include/uapi/linux/pcitest.h > +++ b/include/uapi/linux/pcitest.h > @@ -20,6 +20,7 @@ > #define PCITEST_SET_IRQTYPE _IOW('P', 0x8, int) > #define PCITEST_GET_IRQTYPE _IO('P', 0x9) > #define PCITEST_CLEAR_IRQ _IO('P', 0x10) > +#define PCITEST_DOORBELL _IO('P', 0x11) > > #define PCITEST_FLAGS_USE_DMA 0x00000001 > > -- > 2.34.1 > -- மணிவண்ணன் சதாசிவம்