[PATCH v5 18/24] misc: Add host side pci driver for pci test function device

Kishon Vijay Abraham I
2017-03-27T09:45:14Z

Add PCI endpoint test driver that can verify base address
register, legacy interrupt/MSI interrupt and read/write/copy
buffers between host and device. The corresponding pci-epf-test
function driver should be used on the EP side.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
---
drivers/misc/Kconfig | 7 +
drivers/misc/Makefile | 1 +
drivers/misc/pci_endpoint_test.c | 534 +++++++++++++++++++++++++++++++++++++++
include/uapi/linux/Kbuild | 1 +
include/uapi/linux/pcitest.h | 19 ++
5 files changed, 562 insertions(+)
create mode 100644 drivers/misc/pci_endpoint_test.c
create mode 100644 include/uapi/linux/pcitest.h

diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index c290990d73ed..15ac29d7a840 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -771,6 +771,13 @@ config PANEL_BOOT_MESSAGE

endif # PANEL

+config PCI_ENDPOINT_TEST
+ depends on PCI || COMPILE_TEST
+ tristate "PCI Endpoint Test driver"
+ ---help---
+ Enable this configuration option to enable the host side test driver
+ for PCI Endpoint.
+
source "drivers/misc/c2port/Kconfig"
source "drivers/misc/eeprom/Kconfig"
source "drivers/misc/cb710/Kconfig"
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 7a3ea89339b4..6e139cd70421 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -54,6 +54,7 @@ obj-$(CONFIG_ECHO) += echo/
obj-$(CONFIG_VEXPRESS_SYSCFG) += vexpress-syscfg.o
obj-$(CONFIG_CXL_BASE) += cxl/
obj-$(CONFIG_PANEL) += panel.o
+obj-$(CONFIG_PCI_ENDPOINT_TEST) += pci_endpoint_test.o

lkdtm-$(CONFIG_LKDTM) += lkdtm_core.o
lkdtm-$(CONFIG_LKDTM) += lkdtm_bugs.o
diff --git a/drivers/misc/pci_endpoint_test.c b/drivers/misc/pci_endpoint_test.c
new file mode 100644
index 000000000000..5f4f8f8ff1c2
--- /dev/null
+++ b/drivers/misc/pci_endpoint_test.c
@@ -0,0 +1,534 @@
+/**
+ * Host side test driver to test endpoint functionality
+ *
+ * Copyright (C) 2017 Texas Instruments
+ * Author: Kishon Vijay Abraham I <kishon@ti.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 of
+ * the License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/crc32.h>
+#include <linux/delay.h>
+#include <linux/fs.h>
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/random.h>
+#include <linux/slab.h>
+#include <linux/pci.h>
+#include <linux/pci_ids.h>
+
+#include <linux/pci_regs.h>
+
+#include <uapi/linux/pcitest.h>
+
+#define DRV_MODULE_NAME "pci-endpoint-test"
+
+#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)
+#define MSI_NUMBER_SHIFT 2
+/* 6 bits for MSI number */
+#define COMMAND_READ BIT(8)
+#define COMMAND_WRITE BIT(9)
+#define COMMAND_COPY BIT(10)
+
+#define PCI_ENDPOINT_TEST_STATUS 0x8
+#define STATUS_READ_SUCCESS BIT(0)
+#define STATUS_READ_FAIL BIT(1)
+#define STATUS_WRITE_SUCCESS BIT(2)
+#define STATUS_WRITE_FAIL BIT(3)
+#define STATUS_COPY_SUCCESS BIT(4)
+#define STATUS_COPY_FAIL BIT(5)
+#define STATUS_IRQ_RAISED BIT(6)
+#define STATUS_SRC_ADDR_INVALID BIT(7)
+#define STATUS_DST_ADDR_INVALID BIT(8)
+
+#define PCI_ENDPOINT_TEST_LOWER_SRC_ADDR 0xc
+#define PCI_ENDPOINT_TEST_UPPER_SRC_ADDR 0x10
+
+#define PCI_ENDPOINT_TEST_LOWER_DST_ADDR 0x14
+#define PCI_ENDPOINT_TEST_UPPER_DST_ADDR 0x18
+
+#define PCI_ENDPOINT_TEST_SIZE 0x1c
+#define PCI_ENDPOINT_TEST_CHECKSUM 0x20
+
+static DEFINE_IDA(pci_endpoint_test_ida);
+
+#define to_endpoint_test(priv) container_of((priv), struct pci_endpoint_test, \
+ miscdev)
+enum pci_barno {
+ BAR_0,
+ BAR_1,
+ BAR_2,
+ BAR_3,
+ BAR_4,
+ BAR_5,
+};
+
+struct pci_endpoint_test {
+ struct pci_dev *pdev;
+ void __iomem *base;
+ void __iomem *bar[6];
+ struct completion irq_raised;
+ int last_irq;
+ /* mutex to protect the ioctls */
+ struct mutex mutex;
+ struct miscdevice miscdev;
+};
+
+static int bar_size[] = { 4, 512, 1024, 16384, 131072, 1048576 };
+
+static inline u32 pci_endpoint_test_readl(struct pci_endpoint_test *test,
+ u32 offset)
+{
+ return readl(test->base + offset);
+}
+
+static inline void pci_endpoint_test_writel(struct pci_endpoint_test *test,
+ u32 offset, u32 value)
+{
+ writel(value, test->base + offset);
+}
+
+static inline u32 pci_endpoint_test_bar_readl(struct pci_endpoint_test *test,
+ int bar, int offset)
+{
+ return readl(test->bar[bar] + offset);
+}
+
+static inline void pci_endpoint_test_bar_writel(struct pci_endpoint_test *test,
+ int bar, u32 offset, u32 value)
+{
+ writel(value, test->bar[bar] + offset);
+}
+
+static irqreturn_t pci_endpoint_test_irqhandler(int irq, void *dev_id)
+{
+ struct pci_endpoint_test *test = dev_id;
+ u32 reg;
+
+ reg = pci_endpoint_test_readl(test, PCI_ENDPOINT_TEST_STATUS);
+ if (reg & STATUS_IRQ_RAISED) {
+ test->last_irq = irq;
+ complete(&test->irq_raised);
+ reg &= ~STATUS_IRQ_RAISED;
+ }
+ pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_STATUS,
+ reg);
+
+ return IRQ_HANDLED;
+}
+
+static bool pci_endpoint_test_bar(struct pci_endpoint_test *test,
+ enum pci_barno barno)
+{
+ int j;
+ u32 val;
+ int size;
+
+ if (!test->bar[barno])
+ return false;
+
+ size = bar_size[barno];
+
+ for (j = 0; j < size; j += 4)
+ pci_endpoint_test_bar_writel(test, barno, j, 0xA0A0A0A0);
+
+ for (j = 0; j < size; j += 4) {
+ val = pci_endpoint_test_bar_readl(test, barno, j);
+ if (val != 0xA0A0A0A0)
+ return false;
+ }
+
+ return true;
+}
+
+static bool pci_endpoint_test_legacy_irq(struct pci_endpoint_test *test)
+{
+ u32 val;
+
+ pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_COMMAND,
+ COMMAND_RAISE_LEGACY_IRQ);
+ val = wait_for_completion_timeout(&test->irq_raised,
+ msecs_to_jiffies(1000));
+ if (!val)
+ return false;
+
+ return true;
+}
+
+static bool pci_endpoint_test_msi_irq(struct pci_endpoint_test *test,
+ u8 msi_num)
+{
+ u32 val;
+ struct pci_dev *pdev = test->pdev;
+
+ pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_COMMAND,
+ msi_num << MSI_NUMBER_SHIFT |
+ COMMAND_RAISE_MSI_IRQ);
+ val = wait_for_completion_timeout(&test->irq_raised,
+ msecs_to_jiffies(1000));
+ if (!val)
+ return false;
+
+ if (test->last_irq - pdev->irq == msi_num - 1)
+ return true;
+
+ return false;
+}
+
+static bool pci_endpoint_test_copy(struct pci_endpoint_test *test, size_t size)
+{
+ bool ret = false;
+ void *src_addr;
+ void *dst_addr;
+ dma_addr_t src_phys_addr;
+ dma_addr_t dst_phys_addr;
+ struct pci_dev *pdev = test->pdev;
+ struct device *dev = &pdev->dev;
+ u32 src_crc32;
+ u32 dst_crc32;
+
+ src_addr = dma_alloc_coherent(dev, size, &src_phys_addr, GFP_KERNEL);
+ if (!src_addr) {
+ dev_err(dev, "failed to allocate source buffer\n");
+ ret = false;
+ goto err;
+ }
+
+ pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_LOWER_SRC_ADDR,
+ lower_32_bits(src_phys_addr));
+
+ pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_UPPER_SRC_ADDR,
+ upper_32_bits(src_phys_addr));
+
+ get_random_bytes(src_addr, size);
+ src_crc32 = crc32_le(~0, src_addr, size);
+
+ dst_addr = dma_alloc_coherent(dev, size, &dst_phys_addr, GFP_KERNEL);
+ if (!dst_addr) {
+ dev_err(dev, "failed to allocate destination address\n");
+ ret = false;
+ goto err_src_addr;
+ }
+
+ pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_LOWER_DST_ADDR,
+ lower_32_bits(dst_phys_addr));
+ pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_UPPER_DST_ADDR,
+ upper_32_bits(dst_phys_addr));
+
+ pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_SIZE,
+ size);
+
+ pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_COMMAND,
+ 1 << MSI_NUMBER_SHIFT | COMMAND_COPY);
+
+ wait_for_completion(&test->irq_raised);
+
+ dst_crc32 = crc32_le(~0, dst_addr, size);
+ if (dst_crc32 == src_crc32)
+ ret = true;
+
+ dma_free_coherent(dev, size, dst_addr, dst_phys_addr);
+
+err_src_addr:
+ dma_free_coherent(dev, size, src_addr, src_phys_addr);
+
+err:
+ return ret;
+}
+
+static bool pci_endpoint_test_write(struct pci_endpoint_test *test, size_t size)
+{
+ bool ret = false;
+ u32 reg;
+ void *addr;
+ dma_addr_t phys_addr;
+ struct pci_dev *pdev = test->pdev;
+ struct device *dev = &pdev->dev;
+ u32 crc32;
+
+ addr = dma_alloc_coherent(dev, size, &phys_addr, GFP_KERNEL);
+ if (!addr) {
+ dev_err(dev, "failed to allocate address\n");
+ ret = false;
+ goto err;
+ }
+
+ get_random_bytes(addr, size);
+
+ crc32 = crc32_le(~0, addr, size);
+ pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_CHECKSUM,
+ crc32);
+
+ pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_LOWER_SRC_ADDR,
+ lower_32_bits(phys_addr));
+ pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_UPPER_SRC_ADDR,
+ upper_32_bits(phys_addr));
+
+ pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_SIZE, size);
+
+ pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_COMMAND,
+ 1 << MSI_NUMBER_SHIFT | COMMAND_READ);
+
+ wait_for_completion(&test->irq_raised);
+
+ reg = pci_endpoint_test_readl(test, PCI_ENDPOINT_TEST_STATUS);
+ if (reg & STATUS_READ_SUCCESS)
+ ret = true;
+
+ dma_free_coherent(dev, size, addr, phys_addr);
+
+err:
+ return ret;
+}
+
+static bool pci_endpoint_test_read(struct pci_endpoint_test *test, size_t size)
+{
+ bool ret = false;
+ void *addr;
+ dma_addr_t phys_addr;
+ struct pci_dev *pdev = test->pdev;
+ struct device *dev = &pdev->dev;
+ u32 crc32;
+
+ addr = dma_alloc_coherent(dev, size, &phys_addr, GFP_KERNEL);
+ if (!addr) {
+ dev_err(dev, "failed to allocate destination address\n");
+ ret = false;
+ goto err;
+ }
+
+ pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_LOWER_DST_ADDR,
+ lower_32_bits(phys_addr));
+ pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_UPPER_DST_ADDR,
+ upper_32_bits(phys_addr));
+
+ pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_SIZE, size);
+
+ pci_endpoint_test_writel(test, PCI_ENDPOINT_TEST_COMMAND,
+ 1 << MSI_NUMBER_SHIFT | COMMAND_WRITE);
+
+ wait_for_completion(&test->irq_raised);
+
+ crc32 = crc32_le(~0, addr, size);
+ if (crc32 == pci_endpoint_test_readl(test, PCI_ENDPOINT_TEST_CHECKSUM))
+ ret = true;
+
+ dma_free_coherent(dev, size, addr, phys_addr);
+err:
+ return ret;
+}
+
+static long pci_endpoint_test_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ int ret = -EINVAL;
+ enum pci_barno bar;
+ struct pci_endpoint_test *test = to_endpoint_test(file->private_data);
+
+ mutex_lock(&test->mutex);
+ switch (cmd) {
+ case PCITEST_BAR:
+ bar = arg;
+ if (bar < 0 || bar > 5)
+ goto ret;
+ ret = pci_endpoint_test_bar(test, bar);
+ break;
+ case PCITEST_LEGACY_IRQ:
+ ret = pci_endpoint_test_legacy_irq(test);
+ break;
+ case PCITEST_MSI:
+ ret = pci_endpoint_test_msi_irq(test, arg);
+ break;
+ case PCITEST_WRITE:
+ ret = pci_endpoint_test_write(test, arg);
+ break;
+ case PCITEST_READ:
+ ret = pci_endpoint_test_read(test, arg);
+ break;
+ case PCITEST_COPY:
+ ret = pci_endpoint_test_copy(test, arg);
+ break;
+ }
+
+ret:
+ mutex_unlock(&test->mutex);
+ return ret;
+}
+
+static const struct file_operations pci_endpoint_test_fops = {
+ .owner = THIS_MODULE,
+ .unlocked_ioctl = pci_endpoint_test_ioctl,
+};
+
+static int pci_endpoint_test_probe(struct pci_dev *pdev,
+ const struct pci_device_id *ent)
+{
+ int i;
+ int err;
+ int irq;
+ int id;
+ char name[20];
+ enum pci_barno bar;
+ void __iomem *base;
+ struct device *dev = &pdev->dev;
+ struct pci_endpoint_test *test;
+ struct miscdevice *misc_device;
+
+ if (pci_is_bridge(pdev))
+ return -ENODEV;
+
+ test = devm_kzalloc(dev, sizeof(*test), GFP_KERNEL);
+ if (!test)
+ return -ENOMEM;
+
+ test->pdev = pdev;
+ init_completion(&test->irq_raised);
+ mutex_init(&test->mutex);
+
+ err = pci_enable_device(pdev);
+ if (err) {
+ dev_err(dev, "Cannot enable PCI device\n");
+ return err;
+ }
+
+ err = pci_request_regions(pdev, DRV_MODULE_NAME);
+ if (err) {
+ dev_err(dev, "Cannot obtain PCI resources\n");
+ goto err_disable_pdev;
+ }
+
+ pci_set_master(pdev);
+
+ irq = pci_alloc_irq_vectors(pdev, 1, 32, PCI_IRQ_MSI);
+ if (irq < 0)
+ dev_err(dev, "failed to get MSI interrupts\n");
+
+ err = devm_request_irq(dev, pdev->irq, pci_endpoint_test_irqhandler,
+ IRQF_SHARED, DRV_MODULE_NAME, test);
+ if (err) {
+ dev_err(dev, "failed to request irq\n");
+ goto err_disable_msi;
+ }
+
+ for (i = 1; i < irq; i++) {
+ err = devm_request_irq(dev, pdev->irq + i,
+ pci_endpoint_test_irqhandler,
+ IRQF_SHARED, DRV_MODULE_NAME, test);
+ if (err)
+ dev_err(dev, "failed to request irq for MSI %d\n",
+ i + 1);
+ }
+
+ for (bar = BAR_0; bar <= BAR_5; bar++) {
+ base = pci_ioremap_bar(pdev, bar);
+ if (!base) {
+ dev_err(dev, "failed to read BAR%d\n", bar);
+ WARN_ON(bar == BAR_0);
+ }
+ test->bar[bar] = base;
+ }
+
+ test->base = test->bar[0];
+ if (!test->base) {
+ dev_err(dev, "Cannot perform PCI test without BAR0\n");
+ goto err_iounmap;
+ }
+
+ pci_set_drvdata(pdev, test);
+
+ id = ida_simple_get(&pci_endpoint_test_ida, 0, 0, GFP_KERNEL);
+ if (id < 0) {
+ dev_err(dev, "unable to get id\n");
+ goto err_iounmap;
+ }
+
+ snprintf(name, sizeof(name), DRV_MODULE_NAME ".%d", id);
+ misc_device = &test->miscdev;
+ misc_device->minor = MISC_DYNAMIC_MINOR;
+ misc_device->name = name;
+ misc_device->fops = &pci_endpoint_test_fops,
+
+ err = misc_register(misc_device);
+ if (err) {
+ dev_err(dev, "failed to register device\n");
+ goto err_ida_remove;
+ }
+
+ return 0;
+
+err_ida_remove:
+ ida_simple_remove(&pci_endpoint_test_ida, id);
+
+err_iounmap:
+ for (bar = BAR_0; bar <= BAR_5; bar++) {
+ if (test->bar[bar])
+ pci_iounmap(pdev, test->bar[bar]);
+ }
+
+err_disable_msi:
+ pci_disable_msi(pdev);
+ pci_release_regions(pdev);
+
+err_disable_pdev:
+ pci_disable_device(pdev);
+
+ return err;
+}
+
+static void pci_endpoint_test_remove(struct pci_dev *pdev)
+{
+ int id;
+ enum pci_barno bar;
+ struct pci_endpoint_test *test = pci_get_drvdata(pdev);
+ struct miscdevice *misc_device = &test->miscdev;
+
+ if (sscanf(misc_device->name, DRV_MODULE_NAME ".%d", &id) != 1)
+ return;
+
+ misc_deregister(&test->miscdev);
+ ida_simple_remove(&pci_endpoint_test_ida, id);
+ for (bar = BAR_0; bar <= BAR_5; bar++) {
+ if (test->bar[bar])
+ pci_iounmap(pdev, test->bar[bar]);
+ }
+ pci_disable_msi(pdev);
+ pci_release_regions(pdev);
+ pci_disable_device(pdev);
+}
+
+static const struct pci_device_id pci_endpoint_test_tbl[] = {
+ { PCI_DEVICE(PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_DRA74x) },
+ { PCI_DEVICE(PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_DRA72x) },
+ { }
+};
+MODULE_DEVICE_TABLE(pci, pci_endpoint_test_tbl);
+
+static struct pci_driver pci_endpoint_test_driver = {
+ .name = DRV_MODULE_NAME,
+ .id_table = pci_endpoint_test_tbl,
+ .probe = pci_endpoint_test_probe,
+ .remove = pci_endpoint_test_remove,
+};
+module_pci_driver(pci_endpoint_test_driver);
+
+MODULE_DESCRIPTION("PCI ENDPOINT TEST HOST DRIVER");
+MODULE_AUTHOR("Kishon Vijay Abraham I <kishon@ti.com>");
+MODULE_LICENSE("GPL v2");
diff --git a/include/uapi/linux/Kbuild b/include/uapi/linux/Kbuild
index dd9820b1c779..baee6db08287 100644
--- a/include/uapi/linux/Kbuild
+++ b/include/uapi/linux/Kbuild
@@ -333,6 +333,7 @@ header-y += parport.h
header-y += patchkey.h
header-y += pci.h
header-y += pci_regs.h
+header-y += pcitest.h
header-y += perf_event.h
header-y += personality.h
header-y += pfkeyv2.h
diff --git a/include/uapi/linux/pcitest.h b/include/uapi/linux/pcitest.h
new file mode 100644
index 000000000000..a6aa10c45ad1
--- /dev/null
+++ b/include/uapi/linux/pcitest.h
@@ -0,0 +1,19 @@
+/**
+ * pcitest.h - PCI test uapi defines
+ *
+ * Copyright (C) 2017 Texas Instruments
+ * Author: Kishon Vijay Abraham I <kishon@ti.com>
+ *
+ */
+
+#ifndef __UAPI_LINUX_PCITEST_H
+#define __UAPI_LINUX_PCITEST_H
+
+#define PCITEST_BAR _IO('P', 0x1)
+#define PCITEST_LEGACY_IRQ _IO('P', 0x2)
+#define PCITEST_MSI _IOW('P', 0x3, int)
+#define PCITEST_WRITE _IOW('P', 0x4, unsigned long)
+#define PCITEST_READ _IOW('P', 0x5, unsigned long)
+#define PCITEST_COPY _IOW('P', 0x6, unsigned long)
+
+#endif /* __UAPI_LINUX_PCITEST_H */
--
2.11.0