Re: [PATCH TIP 05/14] x86/dtb: add early parsing of APIC and IOAPIC
From: Grant Likely
Date: Wed Feb 16 2011 - 16:47:29 EST
On Mon, Jan 24, 2011 at 09:58:53AM +0530, Sebastian Andrzej Siewior wrote:
> The apic & ioapic have to be added to system early because
> native_init_IRQ() requires it. In order to obtain the address of the
> ioapic the device tree has to be unflattened because
> of_address_to_resource() has to work.
There is some work being done to provide a flattree version of of_address_to_resource, but that code isn't ready yet.
> The device tree is relocated to ensure it is always covered by the
> kernel and the boot loader does not have to make assumptions about
> kernel's memory layout.
>
> Cc: devicetree-discuss@xxxxxxxxxxxxxxxx
> Cc: Dirk Brandewie <dirk.brandewie@xxxxxxxxx>
> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
Looks okay to me
Acked-by: Grant Likely <grant.likely@xxxxxxxxxxxx>
> ---
> arch/x86/include/asm/prom.h | 7 +++
> arch/x86/kernel/irqinit.c | 2 +-
> arch/x86/kernel/prom.c | 112 +++++++++++++++++++++++++++++++++++++++++-
> 3 files changed, 117 insertions(+), 4 deletions(-)
>
> diff --git a/arch/x86/include/asm/prom.h b/arch/x86/include/asm/prom.h
> index ed7bb62..bd67ab2 100644
> --- a/arch/x86/include/asm/prom.h
> +++ b/arch/x86/include/asm/prom.h
> @@ -22,10 +22,17 @@
> #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];
> diff --git a/arch/x86/kernel/irqinit.c b/arch/x86/kernel/irqinit.c
> index 149c87f..4cadf86 100644
> --- a/arch/x86/kernel/irqinit.c
> +++ b/arch/x86/kernel/irqinit.c
> @@ -244,7 +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
> diff --git a/arch/x86/kernel/prom.c b/arch/x86/kernel/prom.c
> index 95f9551..e4d53bf 100644
> --- a/arch/x86/kernel/prom.c
> +++ b/arch/x86/kernel/prom.c
> @@ -6,15 +6,20 @@
> #include <linux/interrupt.h>
> #include <linux/list.h>
> #include <linux/of.h>
> +#include <linux/of_address.h>
> #include <linux/of_platform.h>
> #include <linux/slab.h>
>
> #include <asm/irq_controller.h>
> +#include <asm/io_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;
> @@ -90,7 +95,108 @@ void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
>
> void __init add_dtb(u64 data)
> {
> - initial_boot_params = (struct boot_param_header *)
> - 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,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;
> + u32 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();
> }
> --
> 1.7.3.2
>
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