linux/drivers/xen/platform-pci.c
Juergen Gross 37510dd566 xen: simplify evtchn_do_upcall() call maze
There are several functions involved for performing the functionality
of evtchn_do_upcall():

- __xen_evtchn_do_upcall() doing the real work
- xen_hvm_evtchn_do_upcall() just being a wrapper for
  __xen_evtchn_do_upcall(), exposed for external callers
- xen_evtchn_do_upcall() calling __xen_evtchn_do_upcall(), too, but
  without any user

Simplify this maze by:

- removing the unused xen_evtchn_do_upcall()
- removing xen_hvm_evtchn_do_upcall() as the only left caller of
  __xen_evtchn_do_upcall(), while renaming __xen_evtchn_do_upcall() to
  xen_evtchn_do_upcall()

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Juergen Gross <jgross@suse.com>
2023-09-19 07:04:49 +02:00

194 lines
4.2 KiB
C

// 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);