xref: /openbmc/linux/drivers/xen/dbgp.c (revision 22d55f02)
1 // SPDX-License-Identifier: GPL-2.0-only
2 #include <linux/pci.h>
3 #include <linux/usb.h>
4 #include <linux/usb/ehci_def.h>
5 #include <linux/usb/hcd.h>
6 #include <asm/xen/hypercall.h>
7 #include <xen/interface/physdev.h>
8 #include <xen/xen.h>
9 
10 static int xen_dbgp_op(struct usb_hcd *hcd, int op)
11 {
12 #ifdef CONFIG_PCI
13 	const struct device *ctrlr = hcd_to_bus(hcd)->controller;
14 #endif
15 	struct physdev_dbgp_op dbgp;
16 
17 	if (!xen_initial_domain())
18 		return 0;
19 
20 	dbgp.op = op;
21 
22 #ifdef CONFIG_PCI
23 	if (dev_is_pci(ctrlr)) {
24 		const struct pci_dev *pdev = to_pci_dev(ctrlr);
25 
26 		dbgp.u.pci.seg = pci_domain_nr(pdev->bus);
27 		dbgp.u.pci.bus = pdev->bus->number;
28 		dbgp.u.pci.devfn = pdev->devfn;
29 		dbgp.bus = PHYSDEVOP_DBGP_BUS_PCI;
30 	} else
31 #endif
32 		dbgp.bus = PHYSDEVOP_DBGP_BUS_UNKNOWN;
33 
34 	return HYPERVISOR_physdev_op(PHYSDEVOP_dbgp_op, &dbgp);
35 }
36 
37 int xen_dbgp_reset_prep(struct usb_hcd *hcd)
38 {
39 	return xen_dbgp_op(hcd, PHYSDEVOP_DBGP_RESET_PREPARE);
40 }
41 
42 int xen_dbgp_external_startup(struct usb_hcd *hcd)
43 {
44 	return xen_dbgp_op(hcd, PHYSDEVOP_DBGP_RESET_DONE);
45 }
46 
47 #ifndef CONFIG_EARLY_PRINTK_DBGP
48 #include <linux/export.h>
49 EXPORT_SYMBOL_GPL(xen_dbgp_reset_prep);
50 EXPORT_SYMBOL_GPL(xen_dbgp_external_startup);
51 #endif
52