GK SDK 源码库: XMIPCLinuxV100R005C00SPC030 (kernel/tools/open_source excluded)

source/bootloader/u-boot-2020.01/arch/x86/cpu/baytrail/valleyview.c

@@ -0,0 +1,57 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2014, Bin Meng <bmeng.cn@gmail.com>
+ */
+
+#include <common.h>
+#include <mmc.h>
+#include <pci_ids.h>
+#include <asm/irq.h>
+#include <asm/mrccache.h>
+#include <asm/post.h>
+#include <asm/arch/iomap.h>
+
+/* GPIO SUS */
+#define GPIO_SUS_PAD_BASE	(IO_BASE_ADDRESS + IO_BASE_OFFSET_GPSSUS)
+#define GPIO_SUS_DFX5_CONF0	0x150
+#define BYT_TRIG_LVL		BIT(24)
+#define BYT_TRIG_POS		BIT(25)
+
+int arch_cpu_init(void)
+{
+	post_code(POST_CPU_INIT);
+
+	return x86_cpu_init_f();
+}
+
+int arch_misc_init(void)
+{
+	if (!ll_boot_init())
+		return 0;
+
+#ifdef CONFIG_ENABLE_MRC_CACHE
+	/*
+	 * We intend not to check any return value here, as even MRC cache
+	 * is not saved successfully, it is not a severe error that will
+	 * prevent system from continuing to boot.
+	 */
+	mrccache_save();
+#endif
+
+	/*
+	 * For some unknown reason, FSP (gold4) for BayTrail configures
+	 * the GPIO DFX5 PAD to enable level interrupt (bit 24 and 25).
+	 * This does not cause any issue when Linux kernel runs w/ or w/o
+	 * the pinctrl driver for BayTrail. However this causes unstable
+	 * S3 resume if the pinctrl driver is included in the kernel build.
+	 * As this pin keeps generating interrupts during an S3 resume,
+	 * and there is no IRQ requester in the kernel to handle it, the
+	 * kernel seems to hang and does not continue resuming.
+	 *
+	 * Clear the mysterious interrupt bits for this pin.
+	 */
+	clrbits_le32(GPIO_SUS_PAD_BASE + GPIO_SUS_DFX5_CONF0,
+		     BYT_TRIG_LVL | BYT_TRIG_POS);
+
+	return 0;
+}