On Sat, Nov 16, 2024 at 04:20:45AM +0100, Niklas Cassel wrote:
> Add a more advanced BAR test that writes all BARs in one go, and then reads
> them back and verifies that the value matches the BAR number bitwise OR:ed
> with offset, this allows us to verify:
> -The BAR number was what we intended to read.
> -The offset was what we intended to read.
>
> This allows us to detect potential address translation issues on the EP.
>
> Reading back the BAR directly after writing will not allow us to detect the
> case where inbound address translation on the endpoint incorrectly causes
> multiple BARs to be redirected to the same memory region (within the EP).
>
> Signed-off-by: Niklas Cassel <cassel@xxxxxxxxxx>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
- Mani
> ---
> drivers/misc/pci_endpoint_test.c | 88 ++++++++++++++++++++++++++++++++
> include/uapi/linux/pcitest.h | 1 +
> tools/pci/pcitest.c | 16 +++++-
> tools/pci/pcitest.sh | 1 +
> 4 files changed, 105 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/misc/pci_endpoint_test.c b/drivers/misc/pci_endpoint_test.c
> index 3aaaf47fa4ee2..34cb54aef3d8b 100644
> --- a/drivers/misc/pci_endpoint_test.c
> +++ b/drivers/misc/pci_endpoint_test.c
> @@ -322,6 +322,91 @@ static bool pci_endpoint_test_bar(struct pci_endpoint_test *test,
> return true;
> }
>
> +static u32 bar_test_pattern_with_offset(enum pci_barno barno, int offset)
> +{
> + u32 val;
> +
> + /* Keep the BAR pattern in the top byte. */
> + val = bar_test_pattern[barno] & 0xff000000;
> + /* Store the (partial) offset in the remaining bytes. */
> + val |= offset & 0x00ffffff;
> +
> + return val;
> +}
> +
> +static bool pci_endpoint_test_bars_write_bar(struct pci_endpoint_test *test,
> + enum pci_barno barno)
> +{
> + struct pci_dev *pdev = test->pdev;
> + int j, size;
> +
> + size = pci_resource_len(pdev, barno);
> +
> + if (barno == test->test_reg_bar)
> + size = 0x4;
> +
> + for (j = 0; j < size; j += 4)
> + writel_relaxed(bar_test_pattern_with_offset(barno, j),
> + test->bar[barno] + j);
> +
> + return true;
> +}
> +
> +static bool pci_endpoint_test_bars_read_bar(struct pci_endpoint_test *test,
> + enum pci_barno barno)
> +{
> + struct pci_dev *pdev = test->pdev;
> + struct device *dev = &pdev->dev;
> + int j, size;
> + u32 val;
> +
> + size = pci_resource_len(pdev, barno);
> +
> + if (barno == test->test_reg_bar)
> + size = 0x4;
> +
> + for (j = 0; j < size; j += 4) {
> + u32 expected = bar_test_pattern_with_offset(barno, j);
> +
> + val = readl_relaxed(test->bar[barno] + j);
> + if (val != expected) {
> + dev_err(dev,
> + "BAR%d incorrect data at offset: %#x, got: %#x expected: %#x\n",
> + barno, j, val, expected);
> + return false;
> + }
> + }
> +
> + return true;
> +}
> +
> +static bool pci_endpoint_test_bars(struct pci_endpoint_test *test)
> +{
> + enum pci_barno bar;
> + bool ret;
> +
> + /* Write all BARs in order (without reading). */
> + for (bar = 0; bar < PCI_STD_NUM_BARS; bar++)
> + if (test->bar[bar])
> + pci_endpoint_test_bars_write_bar(test, bar);
> +
> + /*
> + * Read all BARs in order (without writing).
> + * If there is an address translation issue on the EP, writing one BAR
> + * might have overwritten another BAR. Ensure that this is not the case.
> + * (Reading back the BAR directly after writing can not detect this.)
> + */
> + for (bar = 0; bar < PCI_STD_NUM_BARS; bar++) {
> + if (test->bar[bar]) {
> + ret = pci_endpoint_test_bars_read_bar(test, bar);
> + if (!ret)
> + return ret;
> + }
> + }
> +
> + return true;
> +}
> +
> static bool pci_endpoint_test_intx_irq(struct pci_endpoint_test *test)
> {
> u32 val;
> @@ -768,6 +853,9 @@ static long pci_endpoint_test_ioctl(struct file *file, unsigned int cmd,
> goto ret;
> ret = pci_endpoint_test_bar(test, bar);
> break;
> + case PCITEST_BARS:
> + ret = pci_endpoint_test_bars(test);
> + break;
> case PCITEST_INTX_IRQ:
> ret = pci_endpoint_test_intx_irq(test);
> break;
> diff --git a/include/uapi/linux/pcitest.h b/include/uapi/linux/pcitest.h
> index 94b46b043b536..acd261f498666 100644
> --- a/include/uapi/linux/pcitest.h
> +++ b/include/uapi/linux/pcitest.h
> @@ -20,6 +20,7 @@
> #define PCITEST_MSIX _IOW('P', 0x7, int)
> #define PCITEST_SET_IRQTYPE _IOW('P', 0x8, int)
> #define PCITEST_GET_IRQTYPE _IO('P', 0x9)
> +#define PCITEST_BARS _IO('P', 0xa)
> #define PCITEST_CLEAR_IRQ _IO('P', 0x10)
>
> #define PCITEST_FLAGS_USE_DMA 0x00000001
> diff --git a/tools/pci/pcitest.c b/tools/pci/pcitest.c
> index 470258009ddc2..2ce56ea56202c 100644
> --- a/tools/pci/pcitest.c
> +++ b/tools/pci/pcitest.c
> @@ -22,6 +22,7 @@ static char *irq[] = { "LEGACY", "MSI", "MSI-X" };
> struct pci_test {
> char *device;
> char barnum;
> + bool consecutive_bar_test;
> bool legacyirq;
> unsigned int msinum;
> unsigned int msixnum;
> @@ -57,6 +58,15 @@ static int run_test(struct pci_test *test)
> fprintf(stdout, "%s\n", result[ret]);
> }
>
> + if (test->consecutive_bar_test) {
> + ret = ioctl(fd, PCITEST_BARS);
> + fprintf(stdout, "Consecutive BAR test:\t\t");
> + if (ret < 0)
> + fprintf(stdout, "TEST FAILED\n");
> + else
> + fprintf(stdout, "%s\n", result[ret]);
> + }
> +
> if (test->set_irqtype) {
> ret = ioctl(fd, PCITEST_SET_IRQTYPE, test->irqtype);
> fprintf(stdout, "SET IRQ TYPE TO %s:\t\t", irq[test->irqtype]);
> @@ -172,7 +182,7 @@ int main(int argc, char **argv)
> /* set default endpoint device */
> test->device = "/dev/pci-endpoint-test.0";
>
> - while ((c = getopt(argc, argv, "D:b:m:x:i:deIlhrwcs:")) != EOF)
> + while ((c = getopt(argc, argv, "D:b:Cm:x:i:deIlhrwcs:")) != EOF)
> switch (c) {
> case 'D':
> test->device = optarg;
> @@ -182,6 +192,9 @@ int main(int argc, char **argv)
> if (test->barnum < 0 || test->barnum > 5)
> goto usage;
> continue;
> + case 'C':
> + test->consecutive_bar_test = true;
> + continue;
> case 'l':
> test->legacyirq = true;
> continue;
> @@ -230,6 +243,7 @@ int main(int argc, char **argv)
> "Options:\n"
> "\t-D <dev> PCI endpoint test device {default: /dev/pci-endpoint-test.0}\n"
> "\t-b <bar num> BAR test (bar number between 0..5)\n"
> + "\t-C Consecutive BAR test\n"
> "\t-m <msi num> MSI test (msi number between 1..32)\n"
> "\t-x <msix num> \tMSI-X test (msix number between 1..2048)\n"
> "\t-i <irq type> \tSet IRQ type (0 - Legacy, 1 - MSI, 2 - MSI-X)\n"
> diff --git a/tools/pci/pcitest.sh b/tools/pci/pcitest.sh
> index 75ed48ff29900..770f4d6df34b6 100644
> --- a/tools/pci/pcitest.sh
> +++ b/tools/pci/pcitest.sh
> @@ -11,6 +11,7 @@ do
> pcitest -b $bar
> bar=`expr $bar + 1`
> done
> +pcitest -C
> echo
>
> echo "Interrupt tests"
> --
> 2.47.0
>
--
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