Commit 3879a6f3 authored by Sebastian Andrzej Siewior's avatar Sebastian Andrzej Siewior Committed by Thomas Gleixner
Browse files

x86: dtb: Add early parsing of IO_APIC 



APIC and IO_APIC have to be added to the system early because
native_init_IRQ() requires it.

In order to obtain the address of the ioapic the device tree has to be
unflattened so of_address_to_resource() works.

The device tree is relocated to ensure it is always covered by the
kernel mapping. That way the boot loader does not have to make
any assumptions about kernel's memory layout.

Signed-off-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: default avatarGrant Likely <grant.likely@secretlab.ca>
Cc: sodaville@linutronix.de
Cc: devicetree-discuss@lists.ozlabs.org
Cc: Dirk Brandewie <dirk.brandewie@gmail.com>
LKML-Reference: <1298405266-1624-6-git-send-email-bigeasy@linutronix.de>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
parent 19c4f5f7

arch/x86/include/asm/prom.h

+7 −0
Original line number Diff line number Diff line
@@ -23,10 +23,17 @@ 
#include <asm/irq_controller.h>



#ifdef CONFIG_OF

extern int of_ioapic;

extern u64 initial_dtb;

extern void add_dtb(u64 data);

void x86_dtb_find_config(void);

void x86_dtb_get_config(unsigned int unused);

void add_interrupt_host(struct irq_domain *ih);

#else

static inline void add_dtb(u64 data) { }

#define x86_dtb_find_config x86_init_noop

#define x86_dtb_get_config x86_init_uint_noop

#define of_ioapic 0

#endif



extern char cmd_line[COMMAND_LINE_SIZE];

arch/x86/kernel/devicetree.c

+108 −2
Original line number Diff line number Diff line
@@ -7,15 +7,20 @@ 
#include <linux/list.h>

#include <linux/of.h>

#include <linux/of_fdt.h>

#include <linux/of_address.h>

#include <linux/of_platform.h>

#include <linux/slab.h>



#include <asm/irq_controller.h>

#include <asm/apic.h>



__initdata u64 initial_dtb;

char __initdata cmd_line[COMMAND_LINE_SIZE];

static LIST_HEAD(irq_domains);

static DEFINE_RAW_SPINLOCK(big_irq_lock);



int __initdata of_ioapic;



void add_interrupt_host(struct irq_domain *ih)

{

	unsigned long flags;
@@ -90,6 +95,107 @@ void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align) 


void __init add_dtb(u64 data)

{

	initial_boot_params = phys_to_virt((u64) (u32) data +

				offsetof(struct setup_data, data));

	initial_dtb = data + offsetof(struct setup_data, data);

}



static void __init dtb_lapic_setup(void)

{

#ifdef CONFIG_X86_LOCAL_APIC

	if (apic_force_enable())

		return;



	smp_found_config = 1;

	pic_mode = 1;

	/* Required for ioapic registration */

	set_fixmap_nocache(FIX_APIC_BASE, mp_lapic_addr);

	if (boot_cpu_physical_apicid == -1U)

		boot_cpu_physical_apicid = read_apic_id();



	generic_processor_info(boot_cpu_physical_apicid,

			GET_APIC_VERSION(apic_read(APIC_LVR)));

#endif

}



#ifdef CONFIG_X86_IO_APIC

static unsigned int ioapic_id;



static void __init dtb_add_ioapic(struct device_node *dn)

{

	struct resource r;

	int ret;



	ret = of_address_to_resource(dn, 0, &r);

	if (ret) {

		printk(KERN_ERR "Can't obtain address from node %s.\n",

				dn->full_name);

		return;

	}

	mp_register_ioapic(++ioapic_id, r.start, gsi_top);

}



static void __init dtb_ioapic_setup(void)

{

	struct device_node *dn;



	if (!smp_found_config)

		return;



	for_each_compatible_node(dn, NULL, "intel,ce4100-ioapic")

		dtb_add_ioapic(dn);



	if (nr_ioapics) {

		of_ioapic = 1;

		return;

	}

	printk(KERN_ERR "Error: No information about IO-APIC in OF.\n");

	smp_found_config = 0;

}

#else

static void __init dtb_ioapic_setup(void) {}

#endif



static void __init dtb_apic_setup(void)

{

	dtb_lapic_setup();

	dtb_ioapic_setup();

}



void __init x86_dtb_find_config(void)

{

	if (initial_dtb)

		smp_found_config = 1;

	else

		printk(KERN_ERR "Missing device tree!.\n");

}



void __init x86_dtb_get_config(unsigned int unused)

{

	u32 size, map_len;

	void *new_dtb;



	if (!initial_dtb)

		return;



	map_len = max(PAGE_SIZE - (initial_dtb & ~PAGE_MASK),

			(u64)sizeof(struct boot_param_header));



	initial_boot_params = early_memremap(initial_dtb, map_len);

	size = be32_to_cpu(initial_boot_params->totalsize);

	if (map_len < size) {

		early_iounmap(initial_boot_params, map_len);

		initial_boot_params = early_memremap(initial_dtb, size);

		map_len = size;

	}



	new_dtb = alloc_bootmem(size);

	memcpy(new_dtb, initial_boot_params, size);

	early_iounmap(initial_boot_params, map_len);



	initial_boot_params = new_dtb;



	/* root level address cells */

	of_scan_flat_dt(early_init_dt_scan_root, NULL);



	unflatten_device_tree();

	dtb_apic_setup();

}

arch/x86/kernel/irqinit.c

+2 −1
Original line number Diff line number Diff line
@@ -25,6 +25,7 @@ 
#include <asm/setup.h>

#include <asm/i8259.h>

#include <asm/traps.h>

#include <asm/prom.h>



/*

 * ISA PIC or low IO-APIC triggered (INTA-cycle or APIC) interrupts:
@@ -243,7 +244,7 @@ void __init native_init_IRQ(void) 
			set_intr_gate(i, interrupt[i-FIRST_EXTERNAL_VECTOR]);

	}



	if (!acpi_ioapic)

	if (!acpi_ioapic && !of_ioapic)

		setup_irq(2, &irq2);



#ifdef CONFIG_X86_32

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