diff options
Diffstat (limited to 'drivers/xen/platform-pci.c')
| -rw-r--r-- | drivers/xen/platform-pci.c | 193 |
1 files changed, 193 insertions, 0 deletions
diff --git a/drivers/xen/platform-pci.c b/drivers/xen/platform-pci.c new file mode 100644 index 000000000..544d3f901 --- /dev/null +++ b/drivers/xen/platform-pci.c @@ -0,0 +1,193 @@ +// SPDX-License-Identifier: GPL-2.0-only +/****************************************************************************** + * platform-pci.c + * + * Xen platform PCI device driver + * + * Authors: ssmith@xensource.com and stefano.stabellini@eu.citrix.com + * + * Copyright (c) 2005, Intel Corporation. + * Copyright (c) 2007, XenSource Inc. + * Copyright (c) 2010, Citrix + */ + + +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/init.h> +#include <linux/pci.h> + +#include <xen/platform_pci.h> +#include <xen/grant_table.h> +#include <xen/xenbus.h> +#include <xen/events.h> +#include <xen/hvm.h> +#include <xen/xen-ops.h> + +#define DRV_NAME "xen-platform-pci" + +static unsigned long platform_mmio; +static unsigned long platform_mmio_alloc; +static unsigned long platform_mmiolen; +static uint64_t callback_via; + +static unsigned long alloc_xen_mmio(unsigned long len) +{ + unsigned long addr; + + addr = platform_mmio + platform_mmio_alloc; + platform_mmio_alloc += len; + BUG_ON(platform_mmio_alloc > platform_mmiolen); + + return addr; +} + +static uint64_t get_callback_via(struct pci_dev *pdev) +{ + u8 pin; + int irq; + + irq = pdev->irq; + if (irq < 16) + return irq; /* ISA IRQ */ + + pin = pdev->pin; + + /* We don't know the GSI. Specify the PCI INTx line instead. */ + return ((uint64_t)HVM_PARAM_CALLBACK_TYPE_PCI_INTX << + HVM_CALLBACK_VIA_TYPE_SHIFT) | + ((uint64_t)pci_domain_nr(pdev->bus) << 32) | + ((uint64_t)pdev->bus->number << 16) | + ((uint64_t)(pdev->devfn & 0xff) << 8) | + ((uint64_t)(pin - 1) & 3); +} + +static irqreturn_t do_hvm_evtchn_intr(int irq, void *dev_id) +{ + return xen_evtchn_do_upcall(); +} + +static int xen_allocate_irq(struct pci_dev *pdev) +{ + return request_irq(pdev->irq, do_hvm_evtchn_intr, + IRQF_NOBALANCING | IRQF_SHARED, + "xen-platform-pci", pdev); +} + +static int platform_pci_resume(struct device *dev) +{ + int err; + + if (xen_have_vector_callback) + return 0; + + err = xen_set_callback_via(callback_via); + if (err) { + dev_err(dev, "platform_pci_resume failure!\n"); + return err; + } + return 0; +} + +static int platform_pci_probe(struct pci_dev *pdev, + const struct pci_device_id *ent) +{ + int i, ret; + long ioaddr; + long mmio_addr, mmio_len; + unsigned int max_nr_gframes; + unsigned long grant_frames; + + if (!xen_domain()) + return -ENODEV; + + i = pci_enable_device(pdev); + if (i) + return i; + + ioaddr = pci_resource_start(pdev, 0); + + mmio_addr = pci_resource_start(pdev, 1); + mmio_len = pci_resource_len(pdev, 1); + + if (mmio_addr == 0 || ioaddr == 0) { + dev_err(&pdev->dev, "no resources found\n"); + ret = -ENOENT; + goto pci_out; + } + + ret = pci_request_region(pdev, 1, DRV_NAME); + if (ret < 0) + goto pci_out; + + ret = pci_request_region(pdev, 0, DRV_NAME); + if (ret < 0) + goto mem_out; + + platform_mmio = mmio_addr; + platform_mmiolen = mmio_len; + if (!xen_have_vector_callback) { + ret = xen_allocate_irq(pdev); + if (ret) { + dev_warn(&pdev->dev, "request_irq failed err=%d\n", ret); + goto out; + } + /* + * It doesn't strictly *have* to run on CPU0 but it sure + * as hell better process the event channel ports delivered + * to CPU0. + */ + irq_set_affinity(pdev->irq, cpumask_of(0)); + + callback_via = get_callback_via(pdev); + ret = xen_set_callback_via(callback_via); + if (ret) { + dev_warn(&pdev->dev, "Unable to set the evtchn callback " + "err=%d\n", ret); + goto irq_out; + } + } + + max_nr_gframes = gnttab_max_grant_frames(); + grant_frames = alloc_xen_mmio(PAGE_SIZE * max_nr_gframes); + ret = gnttab_setup_auto_xlat_frames(grant_frames); + if (ret) + goto irq_out; + ret = gnttab_init(); + if (ret) + goto grant_out; + return 0; +grant_out: + gnttab_free_auto_xlat_frames(); +irq_out: + if (!xen_have_vector_callback) + free_irq(pdev->irq, pdev); +out: + pci_release_region(pdev, 0); +mem_out: + pci_release_region(pdev, 1); +pci_out: + pci_disable_device(pdev); + return ret; +} + +static const struct pci_device_id platform_pci_tbl[] = { + {PCI_VENDOR_ID_XEN, PCI_DEVICE_ID_XEN_PLATFORM, + PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0}, + {0,} +}; + +static const struct dev_pm_ops platform_pm_ops = { + .resume_noirq = platform_pci_resume, +}; + +static struct pci_driver platform_driver = { + .name = DRV_NAME, + .probe = platform_pci_probe, + .id_table = platform_pci_tbl, + .driver = { + .pm = &platform_pm_ops, + }, +}; + +builtin_pci_driver(platform_driver); |