Initial import

1 files changed, 191 insertions, 0 deletions

diff --git a/arch/arm/boot/compressed/atags_to_fdt.c b/arch/arm/boot/compressed/atags_to_fdt.c
new file mode 100644
index 000000000..9448aa0c6
--- /dev/null
+++ b/arch/arm/boot/compressed/atags_to_fdt.c
@@ -0,0 +1,191 @@
+#include <asm/setup.h>
+#include <libfdt.h>
+
+#if defined(CONFIG_ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND)
+#define do_extend_cmdline 1
+#else
+#define do_extend_cmdline 0
+#endif
+
+#define NR_BANKS 16
+
+static int node_offset(void *fdt, const char *node_path)
+{
+	int offset = fdt_path_offset(fdt, node_path);
+	if (offset == -FDT_ERR_NOTFOUND)
+		offset = fdt_add_subnode(fdt, 0, node_path);
+	return offset;
+}
+
+static int setprop(void *fdt, const char *node_path, const char *property,
+		   uint32_t *val_array, int size)
+{
+	int offset = node_offset(fdt, node_path);
+	if (offset < 0)
+		return offset;
+	return fdt_setprop(fdt, offset, property, val_array, size);
+}
+
+static int setprop_string(void *fdt, const char *node_path,
+			  const char *property, const char *string)
+{
+	int offset = node_offset(fdt, node_path);
+	if (offset < 0)
+		return offset;
+	return fdt_setprop_string(fdt, offset, property, string);
+}
+
+static int setprop_cell(void *fdt, const char *node_path,
+			const char *property, uint32_t val)
+{
+	int offset = node_offset(fdt, node_path);
+	if (offset < 0)
+		return offset;
+	return fdt_setprop_cell(fdt, offset, property, val);
+}
+
+static const void *getprop(const void *fdt, const char *node_path,
+			   const char *property, int *len)
+{
+	int offset = fdt_path_offset(fdt, node_path);
+
+	if (offset == -FDT_ERR_NOTFOUND)
+		return NULL;
+
+	return fdt_getprop(fdt, offset, property, len);
+}
+
+static uint32_t get_cell_size(const void *fdt)
+{
+	int len;
+	uint32_t cell_size = 1;
+	const uint32_t *size_len =  getprop(fdt, "/", "#size-cells", &len);
+
+	if (size_len)
+		cell_size = fdt32_to_cpu(*size_len);
+	return cell_size;
+}
+
+static void merge_fdt_bootargs(void *fdt, const char *fdt_cmdline)
+{
+	char cmdline[COMMAND_LINE_SIZE];
+	const char *fdt_bootargs;
+	char *ptr = cmdline;
+	int len = 0;
+
+	/* copy the fdt command line into the buffer */
+	fdt_bootargs = getprop(fdt, "/chosen", "bootargs", &len);
+	if (fdt_bootargs)
+		if (len < COMMAND_LINE_SIZE) {
+			memcpy(ptr, fdt_bootargs, len);
+			/* len is the length of the string
+			 * including the NULL terminator */
+			ptr += len - 1;
+		}
+
+	/* and append the ATAG_CMDLINE */
+	if (fdt_cmdline) {
+		len = strlen(fdt_cmdline);
+		if (ptr - cmdline + len + 2 < COMMAND_LINE_SIZE) {
+			*ptr++ = ' ';
+			memcpy(ptr, fdt_cmdline, len);
+			ptr += len;
+		}
+	}
+	*ptr = '\0';
+
+	setprop_string(fdt, "/chosen", "bootargs", cmdline);
+}
+
+/*
+ * Convert and fold provided ATAGs into the provided FDT.
+ *
+ * REturn values:
+ *    = 0 -> pretend success
+ *    = 1 -> bad ATAG (may retry with another possible ATAG pointer)
+ *    < 0 -> error from libfdt
+ */
+int atags_to_fdt(void *atag_list, void *fdt, int total_space)
+{
+	struct tag *atag = atag_list;
+	/* In the case of 64 bits memory size, need to reserve 2 cells for
+	 * address and size for each bank */
+	uint32_t mem_reg_property[2 * 2 * NR_BANKS];
+	int memcount = 0;
+	int ret, memsize;
+
+	/* make sure we've got an aligned pointer */
+	if ((u32)atag_list & 0x3)
+		return 1;
+
+	/* if we get a DTB here we're done already */
+	if (*(u32 *)atag_list == fdt32_to_cpu(FDT_MAGIC))
+	       return 0;
+
+	/* validate the ATAG */
+	if (atag->hdr.tag != ATAG_CORE ||
+	    (atag->hdr.size != tag_size(tag_core) &&
+	     atag->hdr.size != 2))
+		return 1;
+
+	/* let's give it all the room it could need */
+	ret = fdt_open_into(fdt, fdt, total_space);
+	if (ret < 0)
+		return ret;
+
+	for_each_tag(atag, atag_list) {
+		if (atag->hdr.tag == ATAG_CMDLINE) {
+			/* Append the ATAGS command line to the device tree
+			 * command line.
+			 * NB: This means that if the same parameter is set in
+			 * the device tree and in the tags, the one from the
+			 * tags will be chosen.
+			 */
+			if (do_extend_cmdline)
+				merge_fdt_bootargs(fdt,
+						   atag->u.cmdline.cmdline);
+			else
+				setprop_string(fdt, "/chosen", "bootargs",
+					       atag->u.cmdline.cmdline);
+		} else if (atag->hdr.tag == ATAG_MEM) {
+			if (memcount >= sizeof(mem_reg_property)/4)
+				continue;
+			if (!atag->u.mem.size)
+				continue;
+			memsize = get_cell_size(fdt);
+
+			if (memsize == 2) {
+				/* if memsize is 2, that means that
+				 * each data needs 2 cells of 32 bits,
+				 * so the data are 64 bits */
+				uint64_t *mem_reg_prop64 =
+					(uint64_t *)mem_reg_property;
+				mem_reg_prop64[memcount++] =
+					cpu_to_fdt64(atag->u.mem.start);
+				mem_reg_prop64[memcount++] =
+					cpu_to_fdt64(atag->u.mem.size);
+			} else {
+				mem_reg_property[memcount++] =
+					cpu_to_fdt32(atag->u.mem.start);
+				mem_reg_property[memcount++] =
+					cpu_to_fdt32(atag->u.mem.size);
+			}
+
+		} else if (atag->hdr.tag == ATAG_INITRD2) {
+			uint32_t initrd_start, initrd_size;
+			initrd_start = atag->u.initrd.start;
+			initrd_size = atag->u.initrd.size;
+			setprop_cell(fdt, "/chosen", "linux,initrd-start",
+					initrd_start);
+			setprop_cell(fdt, "/chosen", "linux,initrd-end",
+					initrd_start + initrd_size);
+		}
+	}
+
+	if (memcount) {
+		setprop(fdt, "/memory", "reg", mem_reg_property,
+			4 * memcount * memsize);
+	}
+
+	return fdt_pack(fdt);
+}