Re: [PATCH 3/6] pci:host: Add Altera PCIe host controller driver

From: Lorenzo Pieralisi
Date: Wed Jul 29 2015 - 09:19:03 EST


On Tue, Jul 28, 2015 at 11:45:42AM +0100, Ley Foon Tan wrote:

[...]

> +static int altera_pcie_parse_request_of_pci_ranges(struct altera_pcie *pcie)
> +{
> + int err, res_valid = 0;
> + struct device *dev = &pcie->pdev->dev;
> + struct device_node *np = dev->of_node;
> + resource_size_t iobase;
> + struct resource_entry *win;
> + int offset = 0;
> +
> + err = of_pci_get_host_bridge_resources(np, 0, 0xff, &pcie->resources,
> + &iobase);
> + if (err)
> + return err;

On top of Rob's comments on ARM bios32 dependency removal (ie rewrite
the driver so that it does not use pci_common_init_dev()), if you need IO
access you have to map iobase, see pci_remap_iospace() in pci-host-generic.c

Lorenzo

> +
> + resource_list_for_each_entry(win, &pcie->resources) {
> + struct resource *parent, *res = win->res;
> +
> + switch (resource_type(res)) {
> + case IORESOURCE_MEM:
> + parent = &iomem_resource;
> + res_valid |= !(res->flags & IORESOURCE_PREFETCH);
> + cra_writel(pcie, res->start,
> + A2P_ADDR_MAP_LO0 + offset);
> + cra_writel(pcie, 0,
> + A2P_ADDR_MAP_HI0 + offset);
> + offset += ATT_ENTRY_SIZE;
> + break;
> + default:
> + continue;
> + }
> +
> + err = devm_request_resource(dev, parent, res);
> + if (err)
> + goto out_release_res;
> + }
> +
> + if (!res_valid) {
> + dev_err(dev, "non-prefetchable memory resource required\n");
> + err = -EINVAL;
> + goto out_release_res;
> + }
> +
> + return 0;
> +
> +out_release_res:
> + altera_pcie_release_of_pci_ranges(pcie);
> + return err;
> +}
> +
> +static void altera_pcie_free_irq_domain(struct altera_pcie *pcie)
> +{
> + int i;
> + u32 irq;
> +
> + for (i = 0; i < INTX_NUM; i++) {
> + irq = irq_find_mapping(pcie->irq_domain, i);
> + if (irq > 0)
> + irq_dispose_mapping(irq);
> + }
> +
> + irq_domain_remove(pcie->irq_domain);
> +}
> +
> +static int altera_pcie_init_irq_domain(struct altera_pcie *pcie)
> +{
> + struct device *dev = &pcie->pdev->dev;
> + struct device_node *node = dev->of_node;
> +
> + /* Setup INTx */
> + pcie->irq_domain = irq_domain_add_linear(node, INTX_NUM,
> + &intx_domain_ops, pcie);
> + if (!pcie->irq_domain) {
> + dev_err(dev, "Failed to get a INTx IRQ domain\n");
> + return PTR_ERR(pcie->irq_domain);
> + }
> +
> + return 0;
> +}
> +
> +static int altera_pcie_parse_dt(struct altera_pcie *pcie)
> +{
> + struct resource *cra;
> + int ret;
> + struct platform_device *pdev = pcie->pdev;
> +
> + cra = platform_get_resource_byname(pdev, IORESOURCE_MEM, "Cra");
> + pcie->cra_base = devm_ioremap_resource(&pdev->dev, cra);
> + if (IS_ERR(pcie->cra_base)) {
> + dev_err(&pdev->dev, "get Cra resource failed\n");
> + return PTR_ERR(pcie->cra_base);
> + }
> +
> + /* setup IRQ */
> + pcie->hwirq = platform_get_irq(pdev, 0);
> + if (pcie->hwirq <= 0) {
> + dev_err(&pdev->dev, "failed to get IRQ: %d\n", pcie->hwirq);
> + return -EINVAL;
> + }
> + ret = devm_request_irq(&pdev->dev, pcie->hwirq, altera_pcie_isr,
> + IRQF_SHARED, pdev->name, pcie);
> +
> + if (ret) {
> + dev_err(&pdev->dev, "failed to request irq %d\n", pcie->hwirq);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int altera_pcie_probe(struct platform_device *pdev)
> +{
> + struct altera_pcie *pcie;
> + int ret;
> +
> + pcie = devm_kzalloc(&pdev->dev, sizeof(*pcie), GFP_KERNEL);
> + if (!pcie)
> + return -ENOMEM;
> +
> + pcie->pdev = pdev;
> +
> + ret = altera_pcie_parse_dt(pcie);
> + if (ret) {
> + dev_err(&pdev->dev, "Parsing DT failed\n");
> + return ret;
> + }
> +
> + INIT_LIST_HEAD(&pcie->resources);
> +
> + ret = altera_pcie_parse_request_of_pci_ranges(pcie);
> + if (ret) {
> + dev_err(&pdev->dev, "Failed add resources\n");
> + return ret;
> + }
> +
> + ret = altera_pcie_init_irq_domain(pcie);
> + if (ret) {
> + dev_err(&pdev->dev, "Failed creating IRQ Domain\n");
> + return ret;
> + }
> +
> + pcie->root_bus_nr = -1;
> +
> + /* clear all interrupts */
> + cra_writel(pcie, P2A_INT_STS_ALL, P2A_INT_STATUS);
> + /* enable all interrupts */
> + cra_writel(pcie, P2A_INT_ENA_ALL, P2A_INT_ENABLE);
> +
> + altera_pcie_hw.private_data = (void **)&pcie;
> +
> + pci_common_init_dev(&pdev->dev, &altera_pcie_hw);
> +
> + platform_set_drvdata(pdev, pcie);
> + return ret;
> +}
> +
> +static int __exit altera_pcie_remove(struct platform_device *pdev)
> +{
> + struct altera_pcie *pcie = platform_get_drvdata(pdev);
> +
> + altera_pcie_free_irq_domain(pcie);
> + platform_set_drvdata(pdev, NULL);
> + return 0;
> +}
> +
> +static const struct of_device_id altera_pcie_of_match[] = {
> + { .compatible = "altr,pcie-root-port-1.0", },
> + {},
> +};
> +MODULE_DEVICE_TABLE(of, altera_pcie_of_match);
> +
> +static struct platform_driver altera_pcie_driver = {
> + .probe = altera_pcie_probe,
> + .remove = altera_pcie_remove,
> + .driver = {
> + .name = "altera-pcie",
> + .owner = THIS_MODULE,
> + .of_match_table = altera_pcie_of_match,
> + },
> +};
> +
> +module_platform_driver(altera_pcie_driver);
> +
> +MODULE_AUTHOR("Ley Foon Tan <lftan@xxxxxxxxxx>");
> +MODULE_DESCRIPTION("Altera PCIe host controller driver");
> +MODULE_LICENSE("GPL v2");
> --
> 1.8.2.1
>
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