leandrof/u-boot
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Add uboot "fdt_high" enviroment variable

Browse Source 
Add a new "fdt_high" enviroment variable. This can be used to control (or prevent) the
relocation of the flattened device tree on boot. It can be used to prevent relocation
of the fdt into highmem.  The variable behaves similarly to the existing "initrd_high"
variable.

Signed-off-by: David A. Long <dave.long@linaro.org>
This commit is contained in:
David A. Long 2011-07-09 16:40:19 -04:00 committed by Gerald Van Baren
parent a8d2a75d72
commit a28afca57d
2 changed files with 58 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
README
View File

@ -3305,6 +3305,15 @@ List of environment variables (most likely not complete):
This can be used to load and uncompress arbitrary
data.
fdt_high - if set this restricts the maximum address that the
flattened device tree will be copied into upon boot.
If this is set to the special value 0xFFFFFFFF then
the fdt will not be copied at all on boot. For this
to work it must reside in writable memory, have
sufficient padding on the end of it for u-boot to
add the information it needs into it, and the memory
must be accessible by the kernel.
i2cfast - (PPC405GP|PPC405EP only)
if set to 'y' configures Linux I2C driver for fast
mode (400kHZ). This environment variable is used in

60
common/image.c
View File

@ -1234,8 +1234,10 @@ int boot_relocate_fdt (struct lmb *lmb, char **of_flat_tree, ulong *of_size)
{
void *fdt_blob = *of_flat_tree;
void *of_start = 0;
char *fdt_high;
ulong of_len = 0;
int err;
int disable_relocation = 0;
/* nothing to do */
if (*of_size == 0)
@ -1249,26 +1251,62 @@ int boot_relocate_fdt (struct lmb *lmb, char **of_flat_tree, ulong *of_size)
/* position on a 4K boundary before the alloc_current */
/* Pad the FDT by a specified amount */
of_len = *of_size + CONFIG_SYS_FDT_PAD;
of_start = (void *)(unsigned long)lmb_alloc_base(lmb, of_len, 0x1000,
getenv_bootm_mapsize() + getenv_bootm_low());
/* If fdt_high is set use it to select the relocation address */
fdt_high = getenv("fdt_high");
if (fdt_high) {
void *desired_addr = (void *)simple_strtoul(fdt_high, NULL, 16);
if (((ulong) desired_addr) == ~0UL) {
/* All ones means use fdt in place */
desired_addr = fdt_blob;
disable_relocation = 1;
}
if (desired_addr) {
of_start =
(void *)(ulong) lmb_alloc_base(lmb, of_len, 0x1000,
((ulong)
desired_addr)
+ of_len);
if (desired_addr && of_start != desired_addr) {
puts("Failed using fdt_high value for Device Tree");
goto error;
}
} else {
of_start =
(void *)(ulong) mb_alloc(lmb, of_len, 0x1000);
}
} else {
of_start =
(void *)(ulong) lmb_alloc_base(lmb, of_len, 0x1000,
getenv_bootm_mapsize()
+ getenv_bootm_low());
}
if (of_start == 0) {
puts("device tree - allocation error\n");
goto error;
}
debug ("## device tree at %p ... %p (len=%ld [0x%lX])\n",
fdt_blob, fdt_blob + *of_size - 1, of_len, of_len);
if (disable_relocation) {
/* We assume there is space after the existing fdt to use for padding */
fdt_set_totalsize(of_start, of_len);
printf(" Using Device Tree in place at %p, end %p\n",
of_start, of_start + of_len - 1);
} else {
debug ("## device tree at %p ... %p (len=%ld [0x%lX])\n",
fdt_blob, fdt_blob + *of_size - 1, of_len, of_len);
printf (" Loading Device Tree to %p, end %p ... ",
of_start, of_start + of_len - 1);
printf (" Loading Device Tree to %p, end %p ... ",
of_start, of_start + of_len - 1);
err = fdt_open_into (fdt_blob, of_start, of_len);
if (err != 0) {
fdt_error ("fdt move failed");
goto error;
err = fdt_open_into (fdt_blob, of_start, of_len);
if (err != 0) {
fdt_error ("fdt move failed");
goto error;
}
puts ("OK\n");
}
puts ("OK\n");
*of_flat_tree = of_start;
*of_size = of_len;