Add support for LZMA uncompression algorithm.
Signed-off-by: Luigi 'Comio' Mantellini <luigi.mantellini@idf-hit.com>
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
diff --git a/README b/README
index 5135281..a040385 100644
--- a/README
+++ b/README
@@ -1044,6 +1044,29 @@
the malloc area (as defined by CFG_MALLOC_LEN) should
be at least 4MB.
+ CONFIG_LZMA
+
+ If this option is set, support for lzma compressed
+ images is included.
+
+ Note: The LZMA algorithm adds between 2 and 4KB of code and it
+ requires an amount of dynamic memory that is given by the
+ formula:
+
+ (1846 + 768 << (lc + lp)) * sizeof(uint16)
+
+ Where lc and lp stand for, respectively, Literal context bits
+ and Literal pos bits.
+
+ This value is upper-bounded by 14MB in the worst case. Anyway,
+ for a ~4MB large kernel image, we have lc=3 and lp=0 for a
+ total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
+ a very small buffer.
+
+ Use the lzmainfo tool to determinate the lc and lp values and
+ then calculate the amount of needed dynamic memory (ensuring
+ the appropriate CFG_MALLOC_LEN value).
+
- MII/PHY support:
CONFIG_PHY_ADDR