[PATCH v6 2/2] x86/devicetree: Use CPU description from Device Tree

From: Ivan Gorinov <ivan.gorinov@intel.com>
To: Thomas Gleixner <tglx@linutronix.de>,
	Frank Rowand <frowand.list@gmail.com>,
	Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Ingo Molnar <mingo@redhat.com>, Rob Herring <robh+dt@kernel.org>,
	Mark Rutland <mark.rutland@arm.com>
Subject: [PATCH v6 2/2] x86/devicetree: Use CPU description from Device Tree
Date: Tue, 13 Mar 2018 15:05:35 -0700	[thread overview]
Message-ID: <80e8f3018e54b9ceb84615cb543c109f9f6d0985.1520974793.git.ivan.gorinov@intel.com> (raw)
In-Reply-To: <cover.1520974793.git.ivan.gorinov@intel.com>

Current x86 Device Tree implementation does not support multiprocessing.
Use new DT bindings to describe the processors.

Signed-off-by: Ivan Gorinov <ivan.gorinov@intel.com>
---
 arch/x86/kernel/devicetree.c | 39 ++++++++++++++++++++++++++++-----------
 1 file changed, 28 insertions(+), 11 deletions(-)

diff --git a/arch/x86/kernel/devicetree.c b/arch/x86/kernel/devicetree.c
index 5cd387f..a601f08 100644
--- a/arch/x86/kernel/devicetree.c
+++ b/arch/x86/kernel/devicetree.c
@@ -131,31 +131,46 @@ static void __init dtb_setup_hpet(void)
 #endif
 }
 
+static void __init dtb_cpu_setup(void)
+{
+	struct device_node *dn;
+	u32 apic_id, version;
+	int ret;
+
+	version = GET_APIC_VERSION(apic_read(APIC_LVR));
+	for_each_node_by_type(dn, "cpu") {
+		ret = of_property_read_u32(dn, "reg", &apic_id);
+		if (ret < 0) {
+			pr_warn("%pOF: missing local APIC ID\n", dn);
+			continue;
+		}
+		generic_processor_info(apic_id, version);
+	}
+}
+
 static void __init dtb_lapic_setup(void)
 {
 #ifdef CONFIG_X86_LOCAL_APIC
 	struct device_node *dn;
 	struct resource r;
+	unsigned long lapic_addr = APIC_DEFAULT_PHYS_BASE;
 	int ret;
 
 	dn = of_find_compatible_node(NULL, NULL, "intel,ce4100-lapic");
-	if (!dn)
-		return;
-
-	ret = of_address_to_resource(dn, 0, &r);
-	if (WARN_ON(ret))
-		return;
+	if (dn) {
+		ret = of_address_to_resource(dn, 0, &r);
+		if (WARN_ON(ret))
+			return;
+		lapic_addr = r.start;
+	}
 
 	/* Did the boot loader setup the local APIC ? */
 	if (!boot_cpu_has(X86_FEATURE_APIC)) {
-		if (apic_force_enable(r.start))
+		if (apic_force_enable(lapic_addr))
 			return;
 	}
-	smp_found_config = 1;
 	pic_mode = 1;
-	register_lapic_address(r.start);
-	generic_processor_info(boot_cpu_physical_apicid,
-			       GET_APIC_VERSION(apic_read(APIC_LVR)));
+	register_lapic_address(lapic_addr);
 #endif
 }
 
@@ -260,6 +275,7 @@ static void __init dtb_ioapic_setup(void) {}
 static void __init dtb_apic_setup(void)
 {
 	dtb_lapic_setup();
+	dtb_cpu_setup();
 	dtb_ioapic_setup();
 }
 
@@ -297,6 +313,7 @@ void __init x86_dtb_init(void)
 	if (!of_have_populated_dt())
 		return;
 
+	smp_found_config = 1;
 	dtb_setup_hpet();
 	dtb_apic_setup();
 }
-- 
2.7.4
