RE: [PATCH v7 15/18] NTB: Add support for EPF PCI-Express Non-Transparent Bridge

Sherry Sun
2020-11-09T09:37:07Z

Hi Kishon,

> Subject: [PATCH v7 15/18] NTB: Add support for EPF PCI-Express Non-
> Transparent Bridge
>
> From: Kishon Vijay Abraham I <kishon@ti.com>
>
> Add support for EPF PCI-Express Non-Transparent Bridge (NTB) device.
> This driver is platform independent and could be used by any platform which
> have multiple PCIe endpoint instances configured using the pci-epf-ntb driver.
> The driver connnects to the standard NTB sub-system interface. The EPF NTB
> device has configurable number of memory windows (Max 4), configurable
> number of doorbell (Max 32), and configurable number of scratch-pad
> registers.
>
> Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
> ---
> drivers/ntb/hw/Kconfig | 1 +
> drivers/ntb/hw/Makefile | 1 +
> drivers/ntb/hw/epf/Kconfig | 6 +
> drivers/ntb/hw/epf/Makefile | 1 +
> drivers/ntb/hw/epf/ntb_hw_epf.c | 755
> ++++++++++++++++++++++++++++++++
> 5 files changed, 764 insertions(+)
> create mode 100644 drivers/ntb/hw/epf/Kconfig create mode 100644
> drivers/ntb/hw/epf/Makefile create mode 100644
> drivers/ntb/hw/epf/ntb_hw_epf.c
>
> diff --git a/drivers/ntb/hw/Kconfig b/drivers/ntb/hw/Kconfig index
> e77c587060ff..c325be526b80 100644
> --- a/drivers/ntb/hw/Kconfig
> +++ b/drivers/ntb/hw/Kconfig
> @@ -2,4 +2,5 @@
> source "drivers/ntb/hw/amd/Kconfig"
> source "drivers/ntb/hw/idt/Kconfig"
> source "drivers/ntb/hw/intel/Kconfig"
> +source "drivers/ntb/hw/epf/Kconfig"
> source "drivers/ntb/hw/mscc/Kconfig"
> diff --git a/drivers/ntb/hw/Makefile b/drivers/ntb/hw/Makefile index
> 4714d6238845..223ca592b5f9 100644
> --- a/drivers/ntb/hw/Makefile
> +++ b/drivers/ntb/hw/Makefile
> @@ -2,4 +2,5 @@
> obj-$(CONFIG_NTB_AMD) += amd/
> obj-$(CONFIG_NTB_IDT) += idt/
> obj-$(CONFIG_NTB_INTEL) += intel/
> +obj-$(CONFIG_NTB_EPF) += epf/
> obj-$(CONFIG_NTB_SWITCHTEC) += mscc/
> diff --git a/drivers/ntb/hw/epf/Kconfig b/drivers/ntb/hw/epf/Kconfig new
> file mode 100644 index 000000000000..6197d1aab344
> --- /dev/null
> +++ b/drivers/ntb/hw/epf/Kconfig
> @@ -0,0 +1,6 @@
> +config NTB_EPF
> + tristate "Generic EPF Non-Transparent Bridge support"
> + depends on m
> + help
> + This driver supports EPF NTB on configurable endpoint.
> + If unsure, say N.
> diff --git a/drivers/ntb/hw/epf/Makefile b/drivers/ntb/hw/epf/Makefile new
> file mode 100644 index 000000000000..2f560a422bc6
> --- /dev/null
> +++ b/drivers/ntb/hw/epf/Makefile
> @@ -0,0 +1 @@
> +obj-$(CONFIG_NTB_EPF) += ntb_hw_epf.o
> diff --git a/drivers/ntb/hw/epf/ntb_hw_epf.c
> b/drivers/ntb/hw/epf/ntb_hw_epf.c new file mode 100644 index
> 000000000000..0a144987851a
> --- /dev/null
> +++ b/drivers/ntb/hw/epf/ntb_hw_epf.c
> @@ -0,0 +1,755 @@
......
> +static int ntb_epf_init_pci(struct ntb_epf_dev *ndev,
> + struct pci_dev *pdev)
> +{
> + struct device *dev = ndev->dev;
> + int ret;
> +
> + pci_set_drvdata(pdev, ndev);
> +
> + ret = pci_enable_device(pdev);
> + if (ret) {
> + dev_err(dev, "Cannot enable PCI device\n");
> + goto err_pci_enable;
> + }
> +
> + ret = pci_request_regions(pdev, "ntb");
> + if (ret) {
> + dev_err(dev, "Cannot obtain PCI resources\n");
> + goto err_pci_regions;
> + }
> +
> + pci_set_master(pdev);
> +
> + ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(64));
> + if (ret) {
> + ret = dma_set_mask_and_coherent(dev,
> DMA_BIT_MASK(32));
> + if (ret) {
> + dev_err(dev, "Cannot set DMA mask\n");
> + goto err_dma_mask;
> + }
> + dev_warn(&pdev->dev, "Cannot DMA highmem\n");
> + }
> +
> + ndev->ctrl_reg = pci_iomap(pdev, 0, 0);

The second parameter of pci_iomap should be ndev->ctrl_reg_bar instead of the hardcode value 0, right?

> + if (!ndev->ctrl_reg) {
> + ret = -EIO;
> + goto err_dma_mask;
> + }
> +
> + ndev->peer_spad_reg = pci_iomap(pdev, 1, 0);

pci_iomap(pdev, ndev->peer_spad_reg_bar, 0);

> + if (!ndev->peer_spad_reg) {
> + ret = -EIO;
> + goto err_dma_mask;
> + }
> +
> + ndev->db_reg = pci_iomap(pdev, 2, 0);

pci_iomap(pdev, ndev->db_reg_bar, 0);

Best Regards
Sherry