[U-Boot] [PATCH v2 24/27] spl: Add an option to load a FIT containing U-Boot

Simon Glass
2016-02-23T05:55:56Z

This provides a way to load a FIT containing U-Boot and a selection of device
tree files. The board can select the correct device tree by probing the
hardware. Then U-Boot is started with the selected device tree.

Signed-off-by: Simon Glass <sjg@chromium.org>
---

Changes in v2:
- Add a few missing header files

Kconfig | 11 +++
common/spl/Makefile | 1 +
common/spl/spl_fit.c | 194 +++++++++++++++++++++++++++++++++++++++++++++++++++
include/image.h | 2 +-
include/spl.h | 18 +++++
5 files changed, 225 insertions(+), 1 deletion(-)
create mode 100644 common/spl/spl_fit.c

diff --git a/Kconfig b/Kconfig
index a9a4938..e7002ed 100644
--- a/Kconfig
+++ b/Kconfig
@@ -273,6 +273,17 @@ config SYS_TEXT_BASE
help
TODO: Move CONFIG_SYS_TEXT_BASE for all the architecture

+config SPL_LOAD_FIT
+ bool "Enable SPL loading U-Boot as a FIT"
+ depends on FIT
+ help
+ Normally with the SPL framework a legacy image is generated as part
+ of the build. This contains U-Boot along with information as to
+ where it should be loaded. This option instead enables generation
+ of a FIT (Flat Image Tree) which provides more flexibility. In
+ particular it can handle selecting from multiple device tree
+ and passing the correct one to U-Boot.
+
config SYS_CLK_FREQ
depends on ARC || ARCH_SUNXI
int "CPU clock frequency"
diff --git a/common/spl/Makefile b/common/spl/Makefile
index 10a4589..2e0f695 100644
--- a/common/spl/Makefile
+++ b/common/spl/Makefile
@@ -10,6 +10,7 @@

ifdef CONFIG_SPL_BUILD
obj-$(CONFIG_SPL_FRAMEWORK) += spl.o
+obj-$(CONFIG_SPL_LOAD_FIT) += spl_fit.o
obj-$(CONFIG_SPL_NOR_SUPPORT) += spl_nor.o
obj-$(CONFIG_SPL_YMODEM_SUPPORT) += spl_ymodem.o
obj-$(CONFIG_SPL_NAND_SUPPORT) += spl_nand.o
diff --git a/common/spl/spl_fit.c b/common/spl/spl_fit.c
new file mode 100644
index 0000000..1a5c027
--- /dev/null
+++ b/common/spl/spl_fit.c
@@ -0,0 +1,194 @@
+/*
+ * Copyright (C) 2016 Google, Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <errno.h>
+#include <image.h>
+#include <libfdt.h>
+#include <spl.h>
+
+static ulong fdt_getprop_u32(const void *fdt, int node, const char *prop)
+{
+ const u32 *cell;
+ int len;
+
+ cell = fdt_getprop(fdt, node, prop, &len);
+ if (len != sizeof(*cell))
+ return -1U;
+ return fdt32_to_cpu(*cell);
+}
+
+static int spl_fit_select_fdt(const void *fdt, int images, int *fdt_offsetp)
+{
+ const char *name, *fdt_name;
+ int conf, node, fdt_node;
+ int len;
+
+ *fdt_offsetp = 0;
+ conf = fdt_path_offset(fdt, FIT_CONFS_PATH);
+ if (conf < 0) {
+ debug("%s: Cannot find /configurations node: %d\n", __func__,
+ conf);
+ return -EINVAL;
+ }
+ for (node = fdt_first_subnode(fdt, conf);
+ node >= 0;
+ node = fdt_next_subnode(fdt, node)) {
+ name = fdt_getprop(fdt, node, "description", &len);
+ if (!name)
+ return -EINVAL;
+ if (board_fit_config_name_match(name))
+ continue;
+
+ debug("Selecting config '%s'", name);
+ fdt_name = fdt_getprop(fdt, node, FIT_FDT_PROP, &len);
+ if (!fdt_name) {
+ debug("%s: Cannot find fdt name property: %d\n",
+ __func__, len);
+ return -EINVAL;
+ }
+
+ debug(", fdt '%s'\n", fdt_name);
+ fdt_node = fdt_subnode_offset(fdt, images, fdt_name);
+ if (fdt_node < 0) {
+ debug("%s: Cannot find fdt node '%s': %d\n",
+ __func__, fdt_name, fdt_node);
+ return -EINVAL;
+ }
+
+ *fdt_offsetp = fdt_getprop_u32(fdt, fdt_node, "data-offset");
+ len = fdt_getprop_u32(fdt, fdt_node, "data-size");
+#ifdef CONFIG_SPL_LIBCOMMON_SUPPORT
+ printf("FIT: Selected '%s'\n", name);
+#endif
+
+ return len;
+ }
+
+#ifdef CONFIG_SPL_LIBCOMMON_SUPPORT
+ printf("No matching DT out of these options:\n");
+ for (node = fdt_first_subnode(fdt, conf);
+ node >= 0;
+ node = fdt_next_subnode(fdt, node)) {
+ name = fdt_getprop(fdt, node, "name", &len);
+ printf(" %s\n", name);
+ }
+#endif
+
+ return -ENOENT;
+}
+
+int spl_load_simple_fit(struct spl_load_info *info, ulong sector, void *fit)
+{
+ int sectors;
+ ulong size, load;
+ unsigned long count;
+ int node, images;
+ void *load_ptr;
+ int fdt_offset, fdt_len;
+ int data_offset, data_size;
+ int base_offset;
+ int src_sector;
+ void *dst;
+
+ /*
+ * Figure out where the external images start. This is the base for the
+ * data-offset properties in each image.
+ */
+ size = fdt_totalsize(fit);
+ size = (size + 3) & ~3;
+ base_offset = (size + 3) & ~3;
+
+ /*
+ * So far we only have one block of data from the FIT. Read the entire
+ * thing, including that first block, placing it so it finishes before
+ * where we will load the image.
+ *
+ * Note that we will load the image such that its first byte will be
+ * at the load address. Since that byte may be part-way through a
+ * block, we may load the image up to one block before the load
+ * address. So take account of that here by subtracting an addition
+ * block length from the FIT start position.
+ *
+ * In fact the FIT has its own load address, but we assume it cannot
+ * be before CONFIG_SYS_TEXT_BASE.
+ */
+ fit = (void *)(CONFIG_SYS_TEXT_BASE - size - info->bl_len);
+ sectors = (size + info->bl_len - 1) / info->bl_len;
+ count = info->read(info, sector, sectors, fit);
+ debug("fit read sector %lx, sectors=%d, dst=%p, count=%lu\n",
+ sector, sectors, fit, count);
+ if (count == 0)
+ return -EIO;
+
+ /* find the firmware image to load */
+ images = fdt_path_offset(fit, FIT_IMAGES_PATH);
+ if (images < 0) {
+ debug("%s: Cannot find /images node: %d\n", __func__, images);
+ return -1;
+ }
+ node = fdt_first_subnode(fit, images);
+ if (node < 0) {
+ debug("%s: Cannot find first image node: %d\n", __func__, node);
+ return -1;
+ }
+
+ /* Get its information and set up the spl_image structure */
+ data_offset = fdt_getprop_u32(fit, node, "data-offset");
+ data_size = fdt_getprop_u32(fit, node, "data-size");
+ load = fdt_getprop_u32(fit, node, "load");
+ debug("data_offset=%x, data_size=%x\n", data_offset, data_size);
+ spl_image.load_addr = load;
+ spl_image.entry_point = load;
+ spl_image.os = IH_OS_U_BOOT;
+
+ /*
+ * Work out where to place the image. We read it so that the first
+ * byte will be@'load'. This may mean we need to load it starting
+ * before then, since we can only read whole blocks.
+ */
+ sectors = (data_size + info->bl_len - 1) / info->bl_len;
+ data_offset += base_offset;
+ load_ptr = (void *)load;
+ debug("U-Boot size %x, data %p\n", data_size, load_ptr);
+ dst = load_ptr - (data_offset % info->bl_len);
+
+ /* Read the image */
+ src_sector = sector + data_offset / info->bl_len;
+ debug("image: data_offset=%x, dst=%p, src_sector=%x, sectors=%x\n",
+ data_offset, dst, src_sector, sectors);
+ count = info->read(info, src_sector, sectors, dst);
+ if (count != sectors)
+ return -EIO;
+
+ /* Figure out which device tree the board wants to use */
+ fdt_len = spl_fit_select_fdt(fit, images, &fdt_offset);
+ if (fdt_len < 0)
+ return fdt_len;
+
+ /*
+ * Read the device tree and place it after the image. There may be
+ * some extra data before it since we can only read entire blocks.
+ */
+ dst = load_ptr + data_size;
+ fdt_offset += base_offset;
+ count = info->read(info, sector + fdt_offset / info->bl_len, sectors,
+ dst);
+ debug("fit read %x sectors to %x, dst %p, data_offset %x\n",
+ sectors, spl_image.load_addr, dst, fdt_offset);
+ if (count != sectors)
+ return -EIO;
+
+ /*
+ * Copy the device tree so that it starts immediately after the image.
+ * After this we will have the U-Boot image and its device tree ready
+ * for us to start.
+ */
+ memcpy(dst, dst + fdt_offset % info->bl_len, fdt_len);
+
+ return 0;
+}
diff --git a/include/image.h b/include/image.h
index 8af2e9b..05c0bd4 100644
--- a/include/image.h
+++ b/include/image.h
@@ -780,7 +780,6 @@ int bootz_setup(ulong image, ulong *start, ulong *end);
/*******************************************************************/
/* New uImage format specific code (prefixed with fit_) */
/*******************************************************************/
-#if IMAGE_ENABLE_FIT

#define FIT_IMAGES_PATH "/images"
#define FIT_CONFS_PATH "/configurations"
@@ -813,6 +812,7 @@ int bootz_setup(ulong image, ulong *start, ulong *end);

#define FIT_MAX_HASH_LEN HASH_MAX_DIGEST_SIZE

+#if IMAGE_ENABLE_FIT
/* cmdline argument format parsing */
int fit_parse_conf(const char *spec, ulong addr_curr,
ulong *addr, const char **conf_name);
diff --git a/include/spl.h b/include/spl.h
index 92cdc04..16f2f6a 100644
--- a/include/spl.h
+++ b/include/spl.h
@@ -29,6 +29,24 @@ struct spl_image_info {
u32 flags;
};

+/*
+ * Information required to load data from a device
+ *
+ * @dev: Pointer to the device, e.g. struct mmc *
+ * @priv: Private data for the device
+ * @bl_len: Block length for reading in bytes
+ * @read: Function to call to read from the device
+ */
+struct spl_load_info {
+ void *dev;
+ void *priv;
+ int bl_len;
+ ulong (*read)(struct spl_load_info *load, ulong sector, ulong count,
+ void *buf);
+};
+
+int spl_load_simple_fit(struct spl_load_info *info, ulong sector, void *fdt);
+
#define SPL_COPY_PAYLOAD_ONLY 1

extern struct spl_image_info spl_image;
--
2.7.0.rc3.207.g0ac5344