x86: Add a simple TPL implementation

Add the required CPU code so that TPL builds correctly. Also update the
SPL code to deal with being booted from TPL.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/arch/x86/include/asm/spl.h b/arch/x86/include/asm/spl.h
index 8cf59d1..27432b2 100644
--- a/arch/x86/include/asm/spl.h
+++ b/arch/x86/include/asm/spl.h
@@ -2,6 +2,19 @@
 /*
  * Copyright (C) 2017 Google, Inc
  * Written by Simon Glass <sjg@chromium.org>
- *
- * This file is required for SPL to build, but is empty.
  */
+
+#ifndef __asm_spl_h
+#define __asm_spl_h
+
+#define CONFIG_SPL_BOARD_LOAD_IMAGE
+
+enum {
+	BOOT_DEVICE_SPI		= 10,
+	BOOT_DEVICE_BOARD,
+	BOOT_DEVICE_CROS_VBOOT,
+};
+
+void jump_to_spl(ulong entry);
+
+#endif
diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile
index 56fd680..436252d 100644
--- a/arch/x86/lib/Makefile
+++ b/arch/x86/lib/Makefile
@@ -43,7 +43,14 @@
 obj-$(CONFIG_CMD_ZBOOT)	+= zimage.o
 endif
 obj-$(CONFIG_HAVE_FSP) += fsp/
-obj-$(CONFIG_SPL_BUILD) += spl.o
+
+ifdef CONFIG_SPL_BUILD
+ifdef CONFIG_TPL_BUILD
+obj-y += tpl.o
+else
+obj-y += spl.o
+endif
+endif
 
 lib-$(CONFIG_USE_PRIVATE_LIBGCC) += div64.o
 
diff --git a/arch/x86/lib/spl.c b/arch/x86/lib/spl.c
index 7d29074..5d5d1a9 100644
--- a/arch/x86/lib/spl.c
+++ b/arch/x86/lib/spl.c
@@ -5,8 +5,10 @@
 
 #include <common.h>
 #include <debug_uart.h>
+#include <malloc.h>
 #include <spl.h>
 #include <asm/cpu.h>
+#include <asm/mrccache.h>
 #include <asm/mtrr.h>
 #include <asm/processor.h>
 #include <asm-generic/sections.h>
@@ -20,6 +22,7 @@
 
 static int x86_spl_init(void)
 {
+#ifndef CONFIG_TPL
 	/*
 	 * TODO(sjg@chromium.org): We use this area of RAM for the stack
 	 * and global_data in SPL. Once U-Boot starts up and releocates it
@@ -27,6 +30,7 @@
 	 * place it immediately below CONFIG_SYS_TEXT_BASE.
 	 */
 	char *ptr = (char *)0x110000;
+#endif
 	int ret;
 
 	debug("%s starting\n", __func__);
@@ -35,27 +39,44 @@
 		debug("%s: spl_init() failed\n", __func__);
 		return ret;
 	}
+#ifdef CONFIG_TPL
+	/* Do a mini-init if TPL has already done the full init */
+	ret = x86_cpu_reinit_f();
+#else
 	ret = arch_cpu_init();
+#endif
 	if (ret) {
 		debug("%s: arch_cpu_init() failed\n", __func__);
 		return ret;
 	}
+#ifndef CONFIG_TPL
 	ret = arch_cpu_init_dm();
 	if (ret) {
 		debug("%s: arch_cpu_init_dm() failed\n", __func__);
 		return ret;
 	}
+#endif
 	preloader_console_init();
+#ifndef CONFIG_TPL
 	ret = print_cpuinfo();
 	if (ret) {
 		debug("%s: print_cpuinfo() failed\n", __func__);
 		return ret;
 	}
+#endif
 	ret = dram_init();
 	if (ret) {
 		debug("%s: dram_init() failed\n", __func__);
 		return ret;
 	}
+	if (IS_ENABLED(CONFIG_ENABLE_MRC_CACHE)) {
+		ret = mrccache_spl_save();
+		if (ret)
+			debug("%s: Failed to write to mrccache (err=%d)\n",
+			      __func__, ret);
+	}
+
+#ifndef CONFIG_TPL
 	memset(&__bss_start, 0, (ulong)&__bss_end - (ulong)&__bss_start);
 
 	/* TODO(sjg@chromium.org): Consider calling cpu_init_r() here */
@@ -80,9 +101,11 @@
 			       (1ULL << 32) - CONFIG_XIP_ROM_SIZE,
 			       CONFIG_XIP_ROM_SIZE);
 	if (ret) {
-		debug("%s: SPI cache setup failed\n", __func__);
+		debug("%s: SPI cache setup failed (err=%d)\n", __func__, ret);
 		return ret;
 	}
+	mtrr_commit(true);
+#endif
 
 	return 0;
 }
@@ -96,9 +119,17 @@
 		debug("Error %d\n", ret);
 		hang();
 	}
-
+#ifdef CONFIG_TPL
+	gd->bd = malloc(sizeof(*gd->bd));
+	if (!gd->bd) {
+		printf("Out of memory for bd_info size %x\n", sizeof(*gd->bd));
+		hang();
+	}
+	board_init_r(gd, 0);
+#else
 	/* Uninit CAR and jump to board_init_f_r() */
 	board_init_f_r_trampoline(gd->start_addr_sp);
+#endif
 }
 
 void board_init_f_r(void)
@@ -144,6 +175,7 @@
 	return -EPERM;
 }
 
+#ifdef CONFIG_X86_RUN_64BIT
 void __noreturn jump_to_image_no_args(struct spl_image_info *spl_image)
 {
 	int ret;
@@ -154,3 +186,11 @@
 	while (1)
 		;
 }
+#endif
+
+void spl_board_init(void)
+{
+#ifndef CONFIG_TPL
+	preloader_console_init();
+#endif
+}
diff --git a/arch/x86/lib/tpl.c b/arch/x86/lib/tpl.c
new file mode 100644
index 0000000..492a2d6
--- /dev/null
+++ b/arch/x86/lib/tpl.c
@@ -0,0 +1,118 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2018 Google, Inc
+ */
+
+#include <common.h>
+#include <debug_uart.h>
+#include <spl.h>
+#include <asm/cpu.h>
+#include <asm/mtrr.h>
+#include <asm/processor.h>
+#include <asm-generic/sections.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+__weak int arch_cpu_init_dm(void)
+{
+	return 0;
+}
+
+static int x86_tpl_init(void)
+{
+	int ret;
+
+	debug("%s starting\n", __func__);
+	ret = spl_init();
+	if (ret) {
+		debug("%s: spl_init() failed\n", __func__);
+		return ret;
+	}
+	ret = arch_cpu_init();
+	if (ret) {
+		debug("%s: arch_cpu_init() failed\n", __func__);
+		return ret;
+	}
+	ret = arch_cpu_init_dm();
+	if (ret) {
+		debug("%s: arch_cpu_init_dm() failed\n", __func__);
+		return ret;
+	}
+	preloader_console_init();
+	ret = print_cpuinfo();
+	if (ret) {
+		debug("%s: print_cpuinfo() failed\n", __func__);
+		return ret;
+	}
+
+	return 0;
+}
+
+void board_init_f(ulong flags)
+{
+	int ret;
+
+	ret = x86_tpl_init();
+	if (ret) {
+		debug("Error %d\n", ret);
+		hang();
+	}
+
+	/* Uninit CAR and jump to board_init_f_r() */
+	board_init_r(gd, 0);
+}
+
+void board_init_f_r(void)
+{
+	/* Not used since we never call board_init_f_r_trampoline() */
+	while (1);
+}
+
+u32 spl_boot_device(void)
+{
+	return IS_ENABLED(CONFIG_CHROMEOS) ? BOOT_DEVICE_CROS_VBOOT :
+		BOOT_DEVICE_BOARD;
+}
+
+int spl_start_uboot(void)
+{
+	return 0;
+}
+
+void spl_board_announce_boot_device(void)
+{
+	printf("SPI flash");
+}
+
+static int spl_board_load_image(struct spl_image_info *spl_image,
+				struct spl_boot_device *bootdev)
+{
+	spl_image->size = CONFIG_SYS_MONITOR_LEN;  /* We don't know SPL size */
+	spl_image->entry_point = CONFIG_SPL_TEXT_BASE;
+	spl_image->load_addr = CONFIG_SPL_TEXT_BASE;
+	spl_image->os = IH_OS_U_BOOT;
+	spl_image->name = "U-Boot";
+
+	debug("Loading to %lx\n", spl_image->load_addr);
+
+	return 0;
+}
+SPL_LOAD_IMAGE_METHOD("SPI", 0, BOOT_DEVICE_BOARD, spl_board_load_image);
+
+int spl_spi_load_image(void)
+{
+	return -EPERM;
+}
+
+void __noreturn jump_to_image_no_args(struct spl_image_info *spl_image)
+{
+	printf("Jumping to U-Boot SPL at %lx\n", (ulong)spl_image->entry_point);
+	jump_to_spl(spl_image->entry_point);
+	while (1)
+		;
+}
+
+void spl_board_init(void)
+{
+	preloader_console_init();
+}