Re: [RESEND PATCH v3 1/5] misc: Add Synopsys DesignWare xData IP driver

+static ssize_t sysfs_write_show(struct kobject *kobj,
+				struct kobj_attribute *attr, char *buf)
+{
+	struct device *dev = kobj2device(kobj);
+	struct pci_dev *pdev = device2pci_dev(dev);
+	struct dw_xdata *dw = pci_get_drvdata(pdev);
+	u64 rate;
+
+	dw_xdata_perf(dw, &rate, true);
+	return sprintf(buf, "%llu MB/s\n", rate);

+}
+
+static ssize_t sysfs_write_store(struct kobject *kobj,
+				 struct kobj_attribute *attr, const char *buf,
+				 size_t count)
+{
+	struct device *dev = kobj2device(kobj);
+	struct pci_dev *pdev = device2pci_dev(dev);
+	struct dw_xdata *dw = pci_get_drvdata(pdev);
+
+	pci_dbg(pdev, "xData: requested write transfer\n");
+	dw_xdata_start(dw, true);
+
+	return count;
+}
+
+struct kobj_attribute sysfs_write_attr = __ATTR(write, 0644,
+						sysfs_write_show,
+						sysfs_write_store);

+
+static ssize_t sysfs_read_show(struct kobject *kobj,
+			       struct kobj_attribute *attr, char *buf)
+{
+	struct device *dev = kobj2device(kobj);
+	struct pci_dev *pdev = device2pci_dev(dev);
+	struct dw_xdata *dw = pci_get_drvdata(pdev);
+	u64 rate;
+
+	dw_xdata_perf(dw, &rate, false);
+	return sprintf(buf, "%llu MB/s\n", rate);

+}
+
+static ssize_t sysfs_read_store(struct kobject *kobj,
+				struct kobj_attribute *attr, const char *buf,
+				size_t count)
+{
+	struct device *dev = kobj2device(kobj);
+	struct pci_dev *pdev = device2pci_dev(dev);
+	struct dw_xdata *dw = pci_get_drvdata(pdev);
+
+	pci_dbg(pdev, "xData: requested read transfer\n");
+	dw_xdata_start(dw, false);
+
+	return count;
+}
+
+struct kobj_attribute sysfs_read_attr = __ATTR(read, 0644,
+					       sysfs_read_show,
+					       sysfs_read_store);

+
+static ssize_t sysfs_stop_store(struct kobject *kobj,
+				struct kobj_attribute *attr, const char *buf,
+				size_t count)
+{
+	struct device *dev = kobj2device(kobj);

+	struct pci_dev *pdev = device2pci_dev(dev);
+	struct dw_xdata *dw = pci_get_drvdata(pdev);
+
+	pci_dbg(pdev, "xData: requested stop any transfer\n");
+	dw_xdata_stop(dw);
+
+	return count;
+}
+
+struct kobj_attribute sysfs_stop_attr = __ATTR(stop, 0644,
+					       NULL,
+					       sysfs_stop_store);
+
+static int dw_xdata_pcie_probe(struct pci_dev *pdev,
+			       const struct pci_device_id *pid)
+{
+	const struct dw_xdata_pcie_data *pdata = (void *)pid->driver_data;
+	struct device *dev = &pdev->dev;
+	struct dw_xdata *dw;
+	u64 addr;
+	int err;
+
+	/* Enable PCI device */
+	err = pcim_enable_device(pdev);
+	if (err) {
+		pci_err(pdev, "enabling device failed\n");
+		return err;
+	}
+
+	/* Mapping PCI BAR regions */
+	err = pcim_iomap_regions(pdev, BIT(pdata->rg_bar), pci_name(pdev));
+	if (err) {
+		pci_err(pdev, "xData BAR I/O remapping failed\n");
+		return err;
+	}
+
+	pci_set_master(pdev);
+
+	/* Allocate memory */
+	dw = devm_kzalloc(&pdev->dev, sizeof(*dw), GFP_KERNEL);
+	if (!dw)
+		return -ENOMEM;
+
+	/* Data structure initialization */
+	dw->rg_region.vaddr = pcim_iomap_table(pdev)[pdata->rg_bar];
+	if (!dw->rg_region.vaddr)
+		return -ENOMEM;
+
+	dw->rg_region.vaddr += pdata->rg_off;
+	dw->rg_region.paddr = pdev->resource[pdata->rg_bar].start;
+	dw->rg_region.paddr += pdata->rg_off;
+	dw->rg_region.sz = pdata->rg_sz;
+
+	dw->max_wr_len = pcie_get_mps(pdev);
+	dw->max_wr_len >>= 2;
+
+	dw->max_rd_len = pcie_get_readrq(pdev);
+	dw->max_rd_len >>= 2;
+
+	dw->pdev = pdev;
+
+	writel(0x0, &(__dw_regs(dw)->RAM_addr));
+	writel(0x0, &(__dw_regs(dw)->RAM_port));
+
+	addr = dw->rg_region.paddr + DW_XDATA_EP_MEM_OFFSET;
+	writel(lower_32_bits(addr), &(__dw_regs(dw)->addr_lsb));
+	writel(upper_32_bits(addr), &(__dw_regs(dw)->addr_msb));
+	pci_dbg(pdev, "xData: target address = 0x%.16llx\n", addr);
+
+	pci_dbg(pdev, "xData: wr_len=%zu, rd_len=%zu\n",
+		dw->max_wr_len * 4, dw->max_rd_len * 4);
+
+	err = sysfs_create_file(&dev->kobj, &sysfs_write_attr.attr);
+	if (err)
+		return err;
+
+	err = sysfs_create_file(&dev->kobj, &sysfs_read_attr.attr);
+	if (err)
+		return err;
+
+	err = sysfs_create_file(&dev->kobj, &sysfs_stop_attr.attr);
+	if (err)
+		return err;