| Message ID | 1338375646-15064-7-git-send-email-agraf@suse.de |
|---|---|
| State | New |
| Headers | show |
On Wed, May 30, 2012 at 01:00:27PM +0200, Alexander Graf wrote: > We want to get rid of the concept of loading an external device tree and instead > generate our own. However, to do this we need to also create a device tree > template programatically. > > This patch adds a helper to create an empty device tree in memory. Hm, this make-an-empty-template thing is common enough that I'll make a helper for it in libfdt.
On 31.05.2012, at 12:55, David Gibson wrote: > On Wed, May 30, 2012 at 01:00:27PM +0200, Alexander Graf wrote: >> We want to get rid of the concept of loading an external device tree and instead >> generate our own. However, to do this we need to also create a device tree >> template programatically. >> >> This patch adds a helper to create an empty device tree in memory. > > Hm, this make-an-empty-template thing is common enough that I'll make > a helper for it in libfdt. Very cool :). That would still mean that we need the in-QEMU helper for a while though, until we can reasonably expect people to have newer versions of libfdt on their systems, right? :) Alex
On Tue, Jun 05, 2012 at 04:07:23PM +0200, Alexander Graf wrote: > > On 31.05.2012, at 12:55, David Gibson wrote: > > > On Wed, May 30, 2012 at 01:00:27PM +0200, Alexander Graf wrote: > >> We want to get rid of the concept of loading an external device tree and instead > >> generate our own. However, to do this we need to also create a device tree > >> template programatically. > >> > >> This patch adds a helper to create an empty device tree in memory. > > > > Hm, this make-an-empty-template thing is common enough that I'll make > > a helper for it in libfdt. > > Very cool :). That would still mean that we need the in-QEMU helper > for a while though, until we can reasonably expect people to have > newer versions of libfdt on their systems, right? :) True. The helper is in upstream libfdt git now, btw.
diff --git a/device_tree.c b/device_tree.c index 6745d17..d4f1f0a 100644 --- a/device_tree.c +++ b/device_tree.c @@ -25,6 +25,43 @@ #include <libfdt.h> +#define FDT_MAX_SIZE 0x10000 + +void *create_device_tree(int *sizep) +{ + void *fdt; + int ret; + + *sizep = FDT_MAX_SIZE; + fdt = g_malloc0(FDT_MAX_SIZE); + ret = fdt_create(fdt, FDT_MAX_SIZE); + if (ret < 0) { + goto fail; + } + ret = fdt_begin_node(fdt, ""); + if (ret < 0) { + goto fail; + } + ret = fdt_end_node(fdt); + if (ret < 0) { + goto fail; + } + ret = fdt_finish(fdt); + if (ret < 0) { + goto fail; + } + ret = fdt_open_into(fdt, fdt, *sizep); + if (ret) { + fprintf(stderr, "Unable to copy device tree in memory\n"); + exit(1); + } + + return fdt; +fail: + fprintf(stderr, "%s Couldn't create dt: %s\n", __func__, fdt_strerror(ret)); + exit(1); +} + void *load_device_tree(const char *filename_path, int *sizep) { int dt_size; diff --git a/device_tree.h b/device_tree.h index 376287a..5464dc7 100644 --- a/device_tree.h +++ b/device_tree.h @@ -14,6 +14,7 @@ #ifndef __DEVICE_TREE_H__ #define __DEVICE_TREE_H__ +void *create_device_tree(int *sizep); void *load_device_tree(const char *filename_path, int *sizep); int qemu_devtree_setprop(void *fdt, const char *node_path,
We want to get rid of the concept of loading an external device tree and instead generate our own. However, to do this we need to also create a device tree template programatically. This patch adds a helper to create an empty device tree in memory. Signed-off-by: Alexander Graf <agraf@suse.de> --- device_tree.c | 37 +++++++++++++++++++++++++++++++++++++ device_tree.h | 1 + 2 files changed, 38 insertions(+), 0 deletions(-)