x86: Support QEMU x86 targets

This commit introduces the initial U-Boot support for QEMU x86 targets.
U-Boot can boot from coreboot as a payload, or directly without coreboot.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org>
Merged in patch 'x86: qemu: Add CMD_NET to qemu-x86_defconfig
   https://patchwork.ozlabs.org/patch/479745/

arch/x86/Kconfig

@@ -17,6 +17,9 @@ choice
 config VENDOR_COREBOOT
 	bool "coreboot"
 
+config VENDOR_EMULATION
+	bool "emulation"
+
 config VENDOR_GOOGLE
 	bool "Google"
 
@@ -27,6 +30,7 @@ endchoice
 
 # board-specific options below
 source "board/coreboot/Kconfig"
+source "board/emulation/Kconfig"
 source "board/google/Kconfig"
 source "board/intel/Kconfig"
 
@@ -34,6 +38,7 @@ source "board/intel/Kconfig"
 source "arch/x86/cpu/baytrail/Kconfig"
 source "arch/x86/cpu/coreboot/Kconfig"
 source "arch/x86/cpu/ivybridge/Kconfig"
+source "arch/x86/cpu/qemu/Kconfig"
 source "arch/x86/cpu/quark/Kconfig"
 source "arch/x86/cpu/queensbay/Kconfig"
 

arch/x86/cpu/Makefile

@@ -14,6 +14,7 @@ obj-y	+= interrupts.o cpu.o call64.o
 
 obj-$(CONFIG_INTEL_BAYTRAIL) += baytrail/
 obj-$(CONFIG_SYS_COREBOOT) += coreboot/
+obj-$(CONFIG_QEMU) += qemu/
 obj-$(CONFIG_NORTHBRIDGE_INTEL_SANDYBRIDGE) += ivybridge/
 obj-$(CONFIG_NORTHBRIDGE_INTEL_IVYBRIDGE) += ivybridge/
 obj-$(CONFIG_INTEL_QUARK) += quark/

arch/x86/cpu/qemu/Kconfig

@@ -0,0 +1,21 @@
+#
+# Copyright (C) 2015, Bin Meng <bmeng.cn@gmail.com>
+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+config QEMU
+	bool
+	select TSC_CALIBRATION_BYPASS
+
+if QEMU
+
+config SYS_CAR_ADDR
+	hex
+	default 0xd0000
+
+config SYS_CAR_SIZE
+	hex
+	default 0x10000
+
+endif

arch/x86/cpu/qemu/Makefile

@@ -0,0 +1,8 @@
+#
+# Copyright (C) 2015, Bin Meng <bmeng.cn@gmail.com>
+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+obj-y += car.o dram.o qemu.o
+obj-$(CONFIG_PCI) += pci.o

arch/x86/cpu/qemu/car.S

@@ -0,0 +1,26 @@
+/*
+ * Copyright (C) 2015, Bin Meng <bmeng.cn@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <config.h>
+#include <asm/post.h>
+
+.globl car_init
+car_init:
+	/* Save the BIST result */
+	movl	%eax, %ebp
+
+	post_code(POST_CAR_START)
+
+	/*
+	 * Since we know we are running inside emulator,
+	 * we can do nothing here for CAR initialization.
+	 */
+
+	/* Restore the BIST result */
+	movl	%ebp, %eax
+
+	post_code(POST_CAR_CPU_CACHE)
+	jmp	car_init_ret

arch/x86/cpu/qemu/dram.c

@@ -0,0 +1,46 @@
+/*
+ * Copyright (C) 2015, Bin Meng <bmeng.cn@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/post.h>
+#include <asm/arch/qemu.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+int dram_init(void)
+{
+	u32 ram;
+
+	outb(HIGH_RAM_ADDR, CMOS_ADDR_PORT);
+	ram = ((u32)inb(CMOS_DATA_PORT)) << 14;
+	outb(LOW_RAM_ADDR, CMOS_ADDR_PORT);
+	ram |= ((u32)inb(CMOS_DATA_PORT)) << 6;
+	ram += 16 * 1024;
+
+	gd->ram_size = ram * 1024;
+	post_code(POST_DRAM);
+
+	return 0;
+}
+
+void dram_init_banksize(void)
+{
+	gd->bd->bi_dram[0].start = 0;
+	gd->bd->bi_dram[0].size = gd->ram_size;
+}
+
+/*
+ * This function looks for the highest region of memory lower than 4GB which
+ * has enough space for U-Boot where U-Boot is aligned on a page boundary.
+ * It overrides the default implementation found elsewhere which simply
+ * picks the end of ram, wherever that may be. The location of the stack,
+ * the relocation address, and how far U-Boot is moved by relocation are
+ * set in the global data structure.
+ */
+ulong board_get_usable_ram_top(ulong total_size)
+{
+	return gd->ram_size;
+}

arch/x86/cpu/qemu/pci.c

@@ -0,0 +1,49 @@
+/*
+ * Copyright (C) 2015, Bin Meng <bmeng.cn@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <pci.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+void board_pci_setup_hose(struct pci_controller *hose)
+{
+	hose->first_busno = 0;
+	hose->last_busno = 0;
+
+	/* PCI memory space */
+	pci_set_region(hose->regions + 0,
+		       CONFIG_PCI_MEM_BUS,
+		       CONFIG_PCI_MEM_PHYS,
+		       CONFIG_PCI_MEM_SIZE,
+		       PCI_REGION_MEM);
+
+	/* PCI IO space */
+	pci_set_region(hose->regions + 1,
+		       CONFIG_PCI_IO_BUS,
+		       CONFIG_PCI_IO_PHYS,
+		       CONFIG_PCI_IO_SIZE,
+		       PCI_REGION_IO);
+
+	pci_set_region(hose->regions + 2,
+		       CONFIG_PCI_PREF_BUS,
+		       CONFIG_PCI_PREF_PHYS,
+		       CONFIG_PCI_PREF_SIZE,
+		       PCI_REGION_PREFETCH);
+
+	pci_set_region(hose->regions + 3,
+		       0,
+		       0,
+		       gd->ram_size,
+		       PCI_REGION_MEM | PCI_REGION_SYS_MEMORY);
+
+	hose->region_count = 4;
+}
+
+int board_pci_post_scan(struct pci_controller *hose)
+{
+	return 0;
+}

arch/x86/cpu/qemu/qemu.c

@@ -0,0 +1,37 @@
+/*
+ * Copyright (C) 2015, Bin Meng <bmeng.cn@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/post.h>
+#include <asm/processor.h>
+
+int arch_cpu_init(void)
+{
+	int ret;
+
+	post_code(POST_CPU_INIT);
+#ifdef CONFIG_SYS_X86_TSC_TIMER
+	timer_set_base(rdtsc());
+#endif
+
+	ret = x86_cpu_init_f();
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+int print_cpuinfo(void)
+{
+	post_code(POST_CPU_INFO);
+	return default_print_cpuinfo();
+}
+
+void reset_cpu(ulong addr)
+{
+	/* cold reset */
+	x86_full_reset();
+}

arch/x86/dts/Makefile

@@ -2,7 +2,8 @@ dtb-y += chromebook_link.dtb \
 	chromebox_panther.dtb \
 	crownbay.dtb \
 	galileo.dtb \
-	minnowmax.dtb
+	minnowmax.dtb \
+	qemu-x86.dtb
 
 targets += $(dtb-y)
 

arch/x86/dts/qemu-x86.dts

@@ -0,0 +1,34 @@
+/*
+ * Copyright (C) 2015, Bin Meng <bmeng.cn@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+/dts-v1/;
+
+/include/ "skeleton.dtsi"
+/include/ "serial.dtsi"
+
+/ {
+	model = "QEMU x86";
+	compatible = "qemu,x86";
+
+	config {
+		silent_console = <0>;
+	};
+
+	chosen {
+		stdout-path = "/serial";
+	};
+
+	pci {
+		compatible = "pci-x86";
+		#address-cells = <3>;
+		#size-cells = <2>;
+		u-boot,dm-pre-reloc;
+		ranges = <0x02000000 0x0 0xc0000000 0xc0000000 0 0x10000000
+			0x42000000 0x0 0xd0000000 0xd0000000 0 0x10000000
+			0x01000000 0x0 0x2000 0x2000 0 0xe000>;
+	};
+
+};

arch/x86/include/asm/arch-qemu/gpio.h

@@ -0,0 +1,13 @@
+/*
+ * Copyright (C) 2015, Bin Meng <bmeng.cn@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef _X86_ARCH_GPIO_H_
+#define _X86_ARCH_GPIO_H_
+
+/* Where in config space is the register that points to the GPIO registers? */
+#define PCI_CFG_GPIOBASE 0x44
+
+#endif /* _X86_ARCH_GPIO_H_ */

arch/x86/include/asm/arch-qemu/qemu.h

@@ -0,0 +1,17 @@
+/*
+ * Copyright (C) 2015, Bin Meng <bmeng.cn@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef _ARCH_QEMU_H_
+#define _ARCH_QEMU_H_
+
+/* I/O Ports */
+#define CMOS_ADDR_PORT		0x70
+#define CMOS_DATA_PORT		0x71
+
+#define LOW_RAM_ADDR		0x34
+#define HIGH_RAM_ADDR		0x35
+
+#endif /* _ARCH_QEMU_H_ */