diff options
Diffstat (limited to 'drivers/dma/ptdma/ptdma-pci.c')
| -rw-r--r-- | drivers/dma/ptdma/ptdma-pci.c | 243 |
1 files changed, 243 insertions, 0 deletions
diff --git a/drivers/dma/ptdma/ptdma-pci.c b/drivers/dma/ptdma/ptdma-pci.c new file mode 100644 index 000000000..22739ff0c --- /dev/null +++ b/drivers/dma/ptdma/ptdma-pci.c @@ -0,0 +1,243 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * AMD Passthru DMA device driver + * -- Based on the CCP driver + * + * Copyright (C) 2016,2021 Advanced Micro Devices, Inc. + * + * Author: Sanjay R Mehta <sanju.mehta@amd.com> + * Author: Tom Lendacky <thomas.lendacky@amd.com> + * Author: Gary R Hook <gary.hook@amd.com> + */ + +#include <linux/device.h> +#include <linux/dma-mapping.h> +#include <linux/delay.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/kthread.h> +#include <linux/module.h> +#include <linux/pci_ids.h> +#include <linux/pci.h> +#include <linux/spinlock.h> + +#include "ptdma.h" + +struct pt_msix { + int msix_count; + struct msix_entry msix_entry; +}; + +/* + * pt_alloc_struct - allocate and initialize the pt_device struct + * + * @dev: device struct of the PTDMA + */ +static struct pt_device *pt_alloc_struct(struct device *dev) +{ + struct pt_device *pt; + + pt = devm_kzalloc(dev, sizeof(*pt), GFP_KERNEL); + + if (!pt) + return NULL; + pt->dev = dev; + + INIT_LIST_HEAD(&pt->cmd); + + return pt; +} + +static int pt_get_msix_irqs(struct pt_device *pt) +{ + struct pt_msix *pt_msix = pt->pt_msix; + struct device *dev = pt->dev; + struct pci_dev *pdev = to_pci_dev(dev); + int ret; + + pt_msix->msix_entry.entry = 0; + + ret = pci_enable_msix_range(pdev, &pt_msix->msix_entry, 1, 1); + if (ret < 0) + return ret; + + pt_msix->msix_count = ret; + + pt->pt_irq = pt_msix->msix_entry.vector; + + return 0; +} + +static int pt_get_msi_irq(struct pt_device *pt) +{ + struct device *dev = pt->dev; + struct pci_dev *pdev = to_pci_dev(dev); + int ret; + + ret = pci_enable_msi(pdev); + if (ret) + return ret; + + pt->pt_irq = pdev->irq; + + return 0; +} + +static int pt_get_irqs(struct pt_device *pt) +{ + struct device *dev = pt->dev; + int ret; + + ret = pt_get_msix_irqs(pt); + if (!ret) + return 0; + + /* Couldn't get MSI-X vectors, try MSI */ + dev_err(dev, "could not enable MSI-X (%d), trying MSI\n", ret); + ret = pt_get_msi_irq(pt); + if (!ret) + return 0; + + /* Couldn't get MSI interrupt */ + dev_err(dev, "could not enable MSI (%d)\n", ret); + + return ret; +} + +static void pt_free_irqs(struct pt_device *pt) +{ + struct pt_msix *pt_msix = pt->pt_msix; + struct device *dev = pt->dev; + struct pci_dev *pdev = to_pci_dev(dev); + + if (pt_msix->msix_count) + pci_disable_msix(pdev); + else if (pt->pt_irq) + pci_disable_msi(pdev); + + pt->pt_irq = 0; +} + +static int pt_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) +{ + struct pt_device *pt; + struct pt_msix *pt_msix; + struct device *dev = &pdev->dev; + void __iomem * const *iomap_table; + int bar_mask; + int ret = -ENOMEM; + + pt = pt_alloc_struct(dev); + if (!pt) + goto e_err; + + pt_msix = devm_kzalloc(dev, sizeof(*pt_msix), GFP_KERNEL); + if (!pt_msix) + goto e_err; + + pt->pt_msix = pt_msix; + pt->dev_vdata = (struct pt_dev_vdata *)id->driver_data; + if (!pt->dev_vdata) { + ret = -ENODEV; + dev_err(dev, "missing driver data\n"); + goto e_err; + } + + ret = pcim_enable_device(pdev); + if (ret) { + dev_err(dev, "pcim_enable_device failed (%d)\n", ret); + goto e_err; + } + + bar_mask = pci_select_bars(pdev, IORESOURCE_MEM); + ret = pcim_iomap_regions(pdev, bar_mask, "ptdma"); + if (ret) { + dev_err(dev, "pcim_iomap_regions failed (%d)\n", ret); + goto e_err; + } + + iomap_table = pcim_iomap_table(pdev); + if (!iomap_table) { + dev_err(dev, "pcim_iomap_table failed\n"); + ret = -ENOMEM; + goto e_err; + } + + pt->io_regs = iomap_table[pt->dev_vdata->bar]; + if (!pt->io_regs) { + dev_err(dev, "ioremap failed\n"); + ret = -ENOMEM; + goto e_err; + } + + ret = pt_get_irqs(pt); + if (ret) + goto e_err; + + pci_set_master(pdev); + + ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(48)); + if (ret) { + ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32)); + if (ret) { + dev_err(dev, "dma_set_mask_and_coherent failed (%d)\n", + ret); + goto e_err; + } + } + + dev_set_drvdata(dev, pt); + + if (pt->dev_vdata) + ret = pt_core_init(pt); + + if (ret) + goto e_err; + + return 0; + +e_err: + dev_err(dev, "initialization failed ret = %d\n", ret); + + return ret; +} + +static void pt_pci_remove(struct pci_dev *pdev) +{ + struct device *dev = &pdev->dev; + struct pt_device *pt = dev_get_drvdata(dev); + + if (!pt) + return; + + if (pt->dev_vdata) + pt_core_destroy(pt); + + pt_free_irqs(pt); +} + +static const struct pt_dev_vdata dev_vdata[] = { + { + .bar = 2, + }, +}; + +static const struct pci_device_id pt_pci_table[] = { + { PCI_VDEVICE(AMD, 0x1498), (kernel_ulong_t)&dev_vdata[0] }, + /* Last entry must be zero */ + { 0, } +}; +MODULE_DEVICE_TABLE(pci, pt_pci_table); + +static struct pci_driver pt_pci_driver = { + .name = "ptdma", + .id_table = pt_pci_table, + .probe = pt_pci_probe, + .remove = pt_pci_remove, +}; + +module_pci_driver(pt_pci_driver); + +MODULE_AUTHOR("Sanjay R Mehta <sanju.mehta@amd.com>"); +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("AMD PassThru DMA driver"); |