1 files changed, 169 insertions, 0 deletions
diff --git a/common/iotrace.c b/common/iotrace.c
new file mode 100644
index 0000000..ced426e
--- /dev/null
+++ b/common/iotrace.c
@@ -0,0 +1,169 @@
+/*
+ * Copyright (c) 2014 Google, Inc.
+ *
+ * SPDX-License-Identifier:     GPL-2.0+
+ */
+
+#define IOTRACE_IMPL
+
+#include <common.h>
+#include <asm/io.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/* Support up to the machine word length for now */
+typedef ulong iovalue_t;
+
+enum iotrace_flags {
+	IOT_8 = 0,
+	IOT_16,
+	IOT_32,
+
+	IOT_READ = 0 << 3,
+	IOT_WRITE = 1 << 3,
+};
+
+/**
+ * struct iotrace_record - Holds a single I/O trace record
+ *
+ * @flags: I/O access type
+ * @addr: Address of access
+ * @value: Value written or read
+ */
+struct iotrace_record {
+	enum iotrace_flags flags;
+	phys_addr_t addr;
+	iovalue_t value;
+};
+
+/**
+ * struct iotrace - current trace status and checksum
+ *
+ * @start:	Start address of iotrace buffer
+ * @size:	Size of iotrace buffer in bytes
+ * @offset:	Current write offset into iotrace buffer
+ * @crc32:	Current value of CRC chceksum of trace records
+ * @enabled:	true if enabled, false if disabled
+ */
+static struct iotrace {
+	ulong start;
+	ulong size;
+	ulong offset;
+	u32 crc32;
+	bool enabled;
+} iotrace;
+
+static void add_record(int flags, const void *ptr, ulong value)
+{
+	struct iotrace_record srec, *rec = &srec;
+
+	/*
+	 * We don't support iotrace before relocation. Since the trace buffer
+	 * is set up by a command, it can't be enabled at present. To change
+	 * this we would need to set the iotrace buffer at build-time. See
+	 * lib/trace.c for how this might be done if you are interested.
+	 */
+	if (!(gd->flags & GD_FLG_RELOC) || !iotrace.enabled)
+		return;
+
+	/* Store it if there is room */
+	if (iotrace.offset + sizeof(*rec) < iotrace.size) {
+		rec = (struct iotrace_record *)map_sysmem(
+					iotrace.start + iotrace.offset,
+					sizeof(value));
+	}
+
+	rec->flags = flags;
+	rec->addr = map_to_sysmem(ptr);
+	rec->value = value;
+
+	/* Update our checksum */
+	iotrace.crc32 = crc32(iotrace.crc32, (unsigned char *)rec,
+			      sizeof(*rec));
+
+	iotrace.offset += sizeof(struct iotrace_record);
+}
+
+u32 iotrace_readl(const void *ptr)
+{
+	u32 v;
+
+	v = readl(ptr);
+	add_record(IOT_32 | IOT_READ, ptr, v);
+
+	return v;
+}
+
+void iotrace_writel(ulong value, const void *ptr)
+{
+	add_record(IOT_32 | IOT_WRITE, ptr, value);
+	writel(value, ptr);
+}
+
+u16 iotrace_readw(const void *ptr)
+{
+	u32 v;
+
+	v = readw(ptr);
+	add_record(IOT_16 | IOT_READ, ptr, v);
+
+	return v;
+}
+
+void iotrace_writew(ulong value, const void *ptr)
+{
+	add_record(IOT_16 | IOT_WRITE, ptr, value);
+	writew(value, ptr);
+}
+
+u8 iotrace_readb(const void *ptr)
+{
+	u32 v;
+
+	v = readb(ptr);
+	add_record(IOT_8 | IOT_READ, ptr, v);
+
+	return v;
+}
+
+void iotrace_writeb(ulong value, const void *ptr)
+{
+	add_record(IOT_8 | IOT_WRITE, ptr, value);
+	writeb(value, ptr);
+}
+
+void iotrace_reset_checksum(void)
+{
+	iotrace.crc32 = 0;
+}
+
+u32 iotrace_get_checksum(void)
+{
+	return iotrace.crc32;
+}
+
+void iotrace_set_enabled(int enable)
+{
+	iotrace.enabled = enable;
+}
+
+int iotrace_get_enabled(void)
+{
+	return iotrace.enabled;
+}
+
+void iotrace_set_buffer(ulong start, ulong size)
+{
+	iotrace.start = start;
+	iotrace.size = size;
+	iotrace.offset = 0;
+	iotrace.crc32 = 0;
+}
+
+void iotrace_get_buffer(ulong *start, ulong *size, ulong *offset, ulong *count)
+{
+	*start = iotrace.start;
+	*size = iotrace.size;
+	*offset = iotrace.offset;
+	*count = iotrace.offset / sizeof(struct iotrace_record);
+}