x86: Add multi-processor init

Most modern x86 CPUs include more than one CPU core. The OS normally requires
that these 'Application Processors' (APs) be brought up by the boot loader.
Add the required support to U-Boot to init additional APs.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

1 files changed, 86 insertions, 0 deletions

diff --git a/arch/x86/include/asm/sipi.h b/arch/x86/include/asm/sipi.h
new file mode 100644
index 0000000..25d7d31
--- /dev/null
+++ b/arch/x86/include/asm/sipi.h
@@ -0,0 +1,86 @@
+/*
+ * Copyright (c) 2015 Gooogle, Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef _ASM_SIPI_H
+#define _ASM_SIPI_H
+
+#define AP_DEFAULT_BASE 0x30000
+#define AP_DEFAULT_SIZE 0x10000
+
+#ifndef __ASSEMBLER__
+
+/**
+ * struct sipi_params_16bit - 16-bit SIPI entry-point parameters
+ *
+ * These are set up in the same space as the SIPI 16-bit code so that each AP
+ * can access the parameters when it boots.
+ *
+ * Each of these must be set up for the AP to boot, except @segment which is
+ * set in the assembly code.
+ *
+ * @ap_start:		32-bit SIPI entry point for U-Boot
+ * @segment:		Code segment for U-Boot
+ * @pad:		Padding (not used)
+ * @gdt_limit:		U-Boot GDT limit (X86_GDT_SIZE - 1)
+ * @gdt:		U-Boot GDT (gd->arch.gdt)
+ * @unused:		Not used
+ */
+struct __packed sipi_params_16bit {
+	u32 ap_start;
+	u16 segment;
+	u16 pad;
+	u16 gdt_limit;
+	u32 gdt;
+	u16 unused;
+};
+
+/**
+ * struct sipi_params - 32-bit SIP entry-point parameters
+ *
+ * These are used by the AP init code and must be set up before the APs start.
+ *
+ * The stack area extends down from @stack_top, with @stack_size allocated
+ * for each AP.
+ *
+ * @idt_ptr:		Interrupt descriptor table pointer
+ * @stack_top:		Top of the AP stack area
+ * @stack_size:		Size of each AP's stack
+ * @microcode_lock:	Used to ensure only one AP loads microcode at once
+ *			0xffffffff enables parallel loading.
+ * @microcode_ptr:	Pointer to microcode, or 0 if none
+ * @msr_table_ptr:	Pointer to saved MSRs, a list of struct saved_msr
+ * @msr_count:		Number of saved MSRs
+ * @c_handler:		C function to call once early init is complete
+ * @ap_count:		Shared atomic value to allocate CPU indexes
+ */
+struct sipi_params {
+	u32 idt_ptr;
+	u32 stack_top;
+	u32 stack_size;
+	u32 microcode_lock;
+	u32 microcode_ptr;
+	u32 msr_table_ptr;
+	u32 msr_count;
+	u32 c_handler;
+	atomic_t ap_count;
+};
+
+/* 16-bit AP entry point */
+void ap_start16(void);
+
+/* end of 16-bit code/data, marks the region to be copied to SIP vector */
+void ap_start16_code_end(void);
+
+/* 32-bit AP entry point */
+void ap_start(void);
+
+extern char sipi_params_16bit[];
+extern char sipi_params[];
+
+#endif /* __ASSEMBLER__ */
+
+#endif