linux/arch/arm/xen/enlighten.c
Ard Biesheuvel f1dddd118c xen/arm: allow console=hvc0 to be omitted for guests
From: Ard Biesheuvel <ard.biesheuvel@linaro.org>

This patch registers hvc0 as the preferred console if no console
has been specified explicitly on the kernel command line.

The purpose is to allow platform agnostic kernels and boot images
(such as distro installers) to boot in a Xen/ARM domU without the
need to modify the command line by hand.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Julien Grall <julien.grall@linaro.org>
2015-05-28 12:23:11 +01:00

307 lines
7.8 KiB
C

#include <xen/xen.h>
#include <xen/events.h>
#include <xen/grant_table.h>
#include <xen/hvm.h>
#include <xen/interface/vcpu.h>
#include <xen/interface/xen.h>
#include <xen/interface/memory.h>
#include <xen/interface/hvm/params.h>
#include <xen/features.h>
#include <xen/platform_pci.h>
#include <xen/xenbus.h>
#include <xen/page.h>
#include <xen/interface/sched.h>
#include <xen/xen-ops.h>
#include <asm/xen/hypervisor.h>
#include <asm/xen/hypercall.h>
#include <asm/system_misc.h>
#include <linux/interrupt.h>
#include <linux/irqreturn.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/of_address.h>
#include <linux/cpuidle.h>
#include <linux/cpufreq.h>
#include <linux/cpu.h>
#include <linux/console.h>
#include <linux/mm.h>
struct start_info _xen_start_info;
struct start_info *xen_start_info = &_xen_start_info;
EXPORT_SYMBOL(xen_start_info);
enum xen_domain_type xen_domain_type = XEN_NATIVE;
EXPORT_SYMBOL(xen_domain_type);
struct shared_info xen_dummy_shared_info;
struct shared_info *HYPERVISOR_shared_info = (void *)&xen_dummy_shared_info;
DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu);
static struct vcpu_info __percpu *xen_vcpu_info;
/* These are unused until we support booting "pre-ballooned" */
unsigned long xen_released_pages;
struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata;
/* TODO: to be removed */
__read_mostly int xen_have_vector_callback;
EXPORT_SYMBOL_GPL(xen_have_vector_callback);
int xen_platform_pci_unplug = XEN_UNPLUG_ALL;
EXPORT_SYMBOL_GPL(xen_platform_pci_unplug);
static __read_mostly unsigned int xen_events_irq;
static __initdata struct device_node *xen_node;
int xen_remap_domain_mfn_array(struct vm_area_struct *vma,
unsigned long addr,
xen_pfn_t *mfn, int nr,
int *err_ptr, pgprot_t prot,
unsigned domid,
struct page **pages)
{
return xen_xlate_remap_gfn_array(vma, addr, mfn, nr, err_ptr,
prot, domid, pages);
}
EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_array);
/* Not used by XENFEAT_auto_translated guests. */
int xen_remap_domain_mfn_range(struct vm_area_struct *vma,
unsigned long addr,
xen_pfn_t mfn, int nr,
pgprot_t prot, unsigned domid,
struct page **pages)
{
return -ENOSYS;
}
EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_range);
int xen_unmap_domain_mfn_range(struct vm_area_struct *vma,
int nr, struct page **pages)
{
return xen_xlate_unmap_gfn_range(vma, nr, pages);
}
EXPORT_SYMBOL_GPL(xen_unmap_domain_mfn_range);
static void xen_percpu_init(void)
{
struct vcpu_register_vcpu_info info;
struct vcpu_info *vcpup;
int err;
int cpu = get_cpu();
pr_info("Xen: initializing cpu%d\n", cpu);
vcpup = per_cpu_ptr(xen_vcpu_info, cpu);
info.mfn = __pa(vcpup) >> PAGE_SHIFT;
info.offset = offset_in_page(vcpup);
err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, &info);
BUG_ON(err);
per_cpu(xen_vcpu, cpu) = vcpup;
enable_percpu_irq(xen_events_irq, 0);
put_cpu();
}
static void xen_restart(enum reboot_mode reboot_mode, const char *cmd)
{
struct sched_shutdown r = { .reason = SHUTDOWN_reboot };
int rc;
rc = HYPERVISOR_sched_op(SCHEDOP_shutdown, &r);
BUG_ON(rc);
}
static void xen_power_off(void)
{
struct sched_shutdown r = { .reason = SHUTDOWN_poweroff };
int rc;
rc = HYPERVISOR_sched_op(SCHEDOP_shutdown, &r);
BUG_ON(rc);
}
static int xen_cpu_notification(struct notifier_block *self,
unsigned long action,
void *hcpu)
{
switch (action) {
case CPU_STARTING:
xen_percpu_init();
break;
default:
break;
}
return NOTIFY_OK;
}
static struct notifier_block xen_cpu_notifier = {
.notifier_call = xen_cpu_notification,
};
static irqreturn_t xen_arm_callback(int irq, void *arg)
{
xen_hvm_evtchn_do_upcall();
return IRQ_HANDLED;
}
/*
* see Documentation/devicetree/bindings/arm/xen.txt for the
* documentation of the Xen Device Tree format.
*/
#define GRANT_TABLE_PHYSADDR 0
void __init xen_early_init(void)
{
int len;
const char *s = NULL;
const char *version = NULL;
const char *xen_prefix = "xen,xen-";
xen_node = of_find_compatible_node(NULL, NULL, "xen,xen");
if (!xen_node) {
pr_debug("No Xen support\n");
return;
}
s = of_get_property(xen_node, "compatible", &len);
if (strlen(xen_prefix) + 3 < len &&
!strncmp(xen_prefix, s, strlen(xen_prefix)))
version = s + strlen(xen_prefix);
if (version == NULL) {
pr_debug("Xen version not found\n");
return;
}
pr_info("Xen %s support found\n", version);
xen_domain_type = XEN_HVM_DOMAIN;
xen_setup_features();
if (xen_feature(XENFEAT_dom0))
xen_start_info->flags |= SIF_INITDOMAIN|SIF_PRIVILEGED;
else
xen_start_info->flags &= ~(SIF_INITDOMAIN|SIF_PRIVILEGED);
if (!console_set_on_cmdline && !xen_initial_domain())
add_preferred_console("hvc", 0, NULL);
}
static int __init xen_guest_init(void)
{
struct xen_add_to_physmap xatp;
struct shared_info *shared_info_page = NULL;
struct resource res;
phys_addr_t grant_frames;
if (!xen_domain())
return 0;
if (of_address_to_resource(xen_node, GRANT_TABLE_PHYSADDR, &res)) {
pr_err("Xen grant table base address not found\n");
return -ENODEV;
}
grant_frames = res.start;
xen_events_irq = irq_of_parse_and_map(xen_node, 0);
if (!xen_events_irq) {
pr_err("Xen event channel interrupt not found\n");
return -ENODEV;
}
shared_info_page = (struct shared_info *)get_zeroed_page(GFP_KERNEL);
if (!shared_info_page) {
pr_err("not enough memory\n");
return -ENOMEM;
}
xatp.domid = DOMID_SELF;
xatp.idx = 0;
xatp.space = XENMAPSPACE_shared_info;
xatp.gpfn = __pa(shared_info_page) >> PAGE_SHIFT;
if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
BUG();
HYPERVISOR_shared_info = (struct shared_info *)shared_info_page;
/* xen_vcpu is a pointer to the vcpu_info struct in the shared_info
* page, we use it in the event channel upcall and in some pvclock
* related functions.
* The shared info contains exactly 1 CPU (the boot CPU). The guest
* is required to use VCPUOP_register_vcpu_info to place vcpu info
* for secondary CPUs as they are brought up.
* For uniformity we use VCPUOP_register_vcpu_info even on cpu0.
*/
xen_vcpu_info = __alloc_percpu(sizeof(struct vcpu_info),
sizeof(struct vcpu_info));
if (xen_vcpu_info == NULL)
return -ENOMEM;
if (gnttab_setup_auto_xlat_frames(grant_frames)) {
free_percpu(xen_vcpu_info);
return -ENOMEM;
}
gnttab_init();
if (!xen_initial_domain())
xenbus_probe(NULL);
/*
* Making sure board specific code will not set up ops for
* cpu idle and cpu freq.
*/
disable_cpuidle();
disable_cpufreq();
xen_init_IRQ();
if (request_percpu_irq(xen_events_irq, xen_arm_callback,
"events", &xen_vcpu)) {
pr_err("Error request IRQ %d\n", xen_events_irq);
return -EINVAL;
}
xen_percpu_init();
register_cpu_notifier(&xen_cpu_notifier);
return 0;
}
early_initcall(xen_guest_init);
static int __init xen_pm_init(void)
{
if (!xen_domain())
return -ENODEV;
pm_power_off = xen_power_off;
arm_pm_restart = xen_restart;
return 0;
}
late_initcall(xen_pm_init);
/* empty stubs */
void xen_arch_pre_suspend(void) { }
void xen_arch_post_suspend(int suspend_cancelled) { }
void xen_timer_resume(void) { }
void xen_arch_resume(void) { }
void xen_arch_suspend(void) { }
/* In the hypervisor.S file. */
EXPORT_SYMBOL_GPL(HYPERVISOR_event_channel_op);
EXPORT_SYMBOL_GPL(HYPERVISOR_grant_table_op);
EXPORT_SYMBOL_GPL(HYPERVISOR_xen_version);
EXPORT_SYMBOL_GPL(HYPERVISOR_console_io);
EXPORT_SYMBOL_GPL(HYPERVISOR_sched_op);
EXPORT_SYMBOL_GPL(HYPERVISOR_hvm_op);
EXPORT_SYMBOL_GPL(HYPERVISOR_memory_op);
EXPORT_SYMBOL_GPL(HYPERVISOR_physdev_op);
EXPORT_SYMBOL_GPL(HYPERVISOR_vcpu_op);
EXPORT_SYMBOL_GPL(HYPERVISOR_tmem_op);
EXPORT_SYMBOL_GPL(HYPERVISOR_multicall);
EXPORT_SYMBOL_GPL(privcmd_call);