diff mbox

[U-Boot,v3,2/8] x86: qemu: add a cpu uclass driver for qemu target

Message ID 1451385354-55472-3-git-send-email-yanmiaobest@gmail.com
State Superseded
Delegated to: Bin Meng
Headers show

Commit Message

Miao Yan Dec. 29, 2015, 10:35 a.m. UTC 
Add a cpu uclass driver for qemu. Previously, the qemu
target gets cpu number from board dts files, which are
manually created at compile time. This does not scale
when more cpus are assigned to guest as the dts files
must be modified as well.

This patch adds a cpu uclass driver for qemu targets
to directly read online cpu number from firmware.

Signed-off-by: <yanmiaobest@gmail.com>
---
Changes in v2:
  - return int from qemu_fwcfg_online_cpus()

 arch/x86/cpu/qemu/Makefile       |  2 +-
 arch/x86/cpu/qemu/cpu.c          | 57 ++++++++++++++++++++++++++++++++++++++++
 arch/x86/dts/qemu-x86_i440fx.dts |  4 +--
 arch/x86/dts/qemu-x86_q35.dts    |  4 +--
 4 files changed, 62 insertions(+), 5 deletions(-)
 create mode 100644 arch/x86/cpu/qemu/cpu.c

Comments

Bin Meng Dec. 30, 2015, 4:04 a.m. UTC | #1 
On Tue, Dec 29, 2015 at 6:35 PM, Miao Yan <yanmiaobest@gmail.com> wrote:
> Add a cpu uclass driver for qemu. Previously, the qemu
> target gets cpu number from board dts files, which are
> manually created at compile time. This does not scale
> when more cpus are assigned to guest as the dts files
> must be modified as well.
>
> This patch adds a cpu uclass driver for qemu targets
> to directly read online cpu number from firmware.
>
> Signed-off-by: <yanmiaobest@gmail.com>
> ---
> Changes in v2:
>   - return int from qemu_fwcfg_online_cpus()
>

Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff mbox

Patch

diff --git a/arch/x86/cpu/qemu/Makefile b/arch/x86/cpu/qemu/Makefile
index ad424ec..027a12f 100644
--- a/arch/x86/cpu/qemu/Makefile
+++ b/arch/x86/cpu/qemu/Makefile
@@ -7,5 +7,5 @@ 
 ifndef CONFIG_EFI_STUB
 obj-y += car.o dram.o
 endif
-obj-y += qemu.o fw_cfg.o
+obj-y += qemu.o fw_cfg.o cpu.o
 obj-$(CONFIG_GENERATE_ACPI_TABLE) += acpi.o dsdt.o
diff --git a/arch/x86/cpu/qemu/cpu.c b/arch/x86/cpu/qemu/cpu.c
new file mode 100644
index 0000000..9bf9a7c
--- /dev/null
+++ b/arch/x86/cpu/qemu/cpu.c
@@ -0,0 +1,57 @@ 
+/*
+ * Copyright (C) 2015, Miao Yan <yanmiaobest@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <cpu.h>
+#include <dm.h>
+#include <errno.h>
+#include <asm/cpu.h>
+#include "fw_cfg.h"
+
+DECLARE_GLOBAL_DATA_PTR;
+
+int cpu_qemu_bind(struct udevice *dev)
+{
+	struct cpu_platdata *plat = dev_get_parent_platdata(dev);
+
+	plat->cpu_id = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
+				      "intel,apic-id", -1);
+
+	return 0;
+}
+
+int cpu_qemu_get_desc(struct udevice *dev, char *buf, int size)
+{
+	if (size < CPU_MAX_NAME_LEN)
+		return -ENOSPC;
+
+	cpu_get_name(buf);
+
+	return 0;
+}
+
+static int cpu_qemu_get_count(struct udevice *dev)
+{
+	return qemu_fwcfg_online_cpus();
+}
+
+static const struct cpu_ops cpu_qemu_ops = {
+	.get_desc	= cpu_qemu_get_desc,
+	.get_count	= cpu_qemu_get_count,
+};
+
+static const struct udevice_id cpu_qemu_ids[] = {
+	{ .compatible = "cpu-qemu" },
+	{ }
+};
+
+U_BOOT_DRIVER(cpu_qemu_drv) = {
+	.name		= "cpu_qemu",
+	.id		= UCLASS_CPU,
+	.of_match	= cpu_qemu_ids,
+	.bind		= cpu_qemu_bind,
+	.ops		= &cpu_qemu_ops,
+};
diff --git a/arch/x86/dts/qemu-x86_i440fx.dts b/arch/x86/dts/qemu-x86_i440fx.dts
index 8a06229..4332204 100644
--- a/arch/x86/dts/qemu-x86_i440fx.dts
+++ b/arch/x86/dts/qemu-x86_i440fx.dts
@@ -32,14 +32,14 @@ 
 
 		cpu@0 {
 			device_type = "cpu";
-			compatible = "cpu-x86";
+			compatible = "cpu-qemu";
 			reg = <0>;
 			intel,apic-id = <0>;
 		};
 
 		cpu@1 {
 			device_type = "cpu";
-			compatible = "cpu-x86";
+			compatible = "cpu-qemu";
 			reg = <1>;
 			intel,apic-id = <1>;
 		};
diff --git a/arch/x86/dts/qemu-x86_q35.dts b/arch/x86/dts/qemu-x86_q35.dts
index 0b685c8..3e2cfac 100644
--- a/arch/x86/dts/qemu-x86_q35.dts
+++ b/arch/x86/dts/qemu-x86_q35.dts
@@ -43,14 +43,14 @@ 
 
 		cpu@0 {
 			device_type = "cpu";
-			compatible = "cpu-x86";
+			compatible = "cpu-qemu";
 			reg = <0>;
 			intel,apic-id = <0>;
 		};
 
 		cpu@1 {
 			device_type = "cpu";
-			compatible = "cpu-x86";
+			compatible = "cpu-qemu";
 			reg = <1>;
 			intel,apic-id = <1>;
 		};