Commit 5882bfef authored by Stefano Stabellini's avatar Stefano Stabellini Committed by David Vrabel
Browse files

arm,arm64/xen: move Xen initialization earlier 



Currently, Xen is initialized/discovered in an initcall. This doesn't
allow us to support earlyprintk or choosing the preferred console when
running on Xen.

The current function xen_guest_init is now split in 2 parts:
    - xen_early_init: Check if there is a Xen node in the device tree
    and setup domain type
    - xen_guest_init: Retrieve the information from the device node and
    initialize Xen (grant table, shared page...)

The former is called in setup_arch, while the latter is an initcall.

Signed-off-by: default avatarStefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: default avatarJulien Grall <julien.grall@linaro.org>
Acked-by: default avatarIan Campbell <ian.campbell@citrix.com>
Acked-by: default avatarWill Deacon <will.deacon@arm.com>
parent 81e863c3

arch/arm/include/asm/xen/hypervisor.h

+8 −0
Original line number Diff line number Diff line 
#ifndef _ASM_ARM_XEN_HYPERVISOR_H

#define _ASM_ARM_XEN_HYPERVISOR_H



#include <linux/init.h>



extern struct shared_info *HYPERVISOR_shared_info;

extern struct start_info *xen_start_info;
@@ -18,4 +20,10 @@ static inline enum paravirt_lazy_mode paravirt_get_lazy_mode(void) 


extern struct dma_map_ops *xen_dma_ops;



#ifdef CONFIG_XEN

void __init xen_early_init(void);

#else

static inline void xen_early_init(void) { return; }

#endif



#endif /* _ASM_ARM_XEN_HYPERVISOR_H */

arch/arm/kernel/setup.c

+2 −0
Original line number Diff line number Diff line
@@ -46,6 +46,7 @@ 
#include <asm/cacheflush.h>

#include <asm/cachetype.h>

#include <asm/tlbflush.h>

#include <asm/xen/hypervisor.h>



#include <asm/prom.h>

#include <asm/mach/arch.h>
@@ -951,6 +952,7 @@ void __init setup_arch(char **cmdline_p) 


	arm_dt_init_cpu_maps();

	psci_init();

	xen_early_init();

#ifdef CONFIG_SMP

	if (is_smp()) {

		if (!mdesc->smp_init || !mdesc->smp_init()) {

arch/arm/xen/enlighten.c

+34 −24
Original line number Diff line number Diff line
@@ -53,6 +53,8 @@ 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,
@@ -150,42 +152,28 @@ static irqreturn_t xen_arm_callback(int irq, void *arg) 
 * documentation of the Xen Device Tree format.

 */

#define GRANT_TABLE_PHYSADDR 0

static int __init xen_guest_init(void)

void __init xen_early_init(void)

{

	struct xen_add_to_physmap xatp;

	static struct shared_info *shared_info_page = 0;

	struct device_node *node;

	int len;

	const char *s = NULL;

	const char *version = NULL;

	const char *xen_prefix = "xen,xen-";

	struct resource res;

	phys_addr_t grant_frames;



	node = of_find_compatible_node(NULL, NULL, "xen,xen");

	if (!node) {

	xen_node = of_find_compatible_node(NULL, NULL, "xen,xen");

	if (!xen_node) {

		pr_debug("No Xen support\n");

		return 0;

		return;

	}

	s = of_get_property(node, "compatible", &len);

	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 0;

	}

	if (of_address_to_resource(node, GRANT_TABLE_PHYSADDR, &res))

		return 0;

	grant_frames = res.start;

	xen_events_irq = irq_of_parse_and_map(node, 0);

	if (!xen_events_irq) {

		pr_debug("Xen event channel interrupt not found\n");

		return -ENODEV;

		return;

	}



	pr_info("Xen %s support found, events_irq=%d gnttab_frame=%pa\n",

			version, xen_events_irq, &grant_frames);

	pr_info("Xen %s support found\n", version);



	xen_domain_type = XEN_HVM_DOMAIN;
@@ -195,10 +183,32 @@ static int __init xen_guest_init(void) 
		xen_start_info->flags |= SIF_INITDOMAIN|SIF_PRIVILEGED;

	else

		xen_start_info->flags &= ~(SIF_INITDOMAIN|SIF_PRIVILEGED);

}



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)

		shared_info_page = (struct shared_info *)

			get_zeroed_page(GFP_KERNEL);

	if (!shared_info_page) {

		pr_err("not enough memory\n");

		return -ENOMEM;

arch/arm64/kernel/setup.c

+2 −0
Original line number Diff line number Diff line
@@ -64,6 +64,7 @@ 
#include <asm/psci.h>

#include <asm/efi.h>

#include <asm/virt.h>

#include <asm/xen/hypervisor.h>



unsigned long elf_hwcap __read_mostly;

EXPORT_SYMBOL_GPL(elf_hwcap);
@@ -416,6 +417,7 @@ void __init setup_arch(char **cmdline_p) 
		psci_acpi_init();

		acpi_init_cpus();

	}

	xen_early_init();



#ifdef CONFIG_SMP

	smp_build_mpidr_hash();

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