From fc9c1727b5b3483ce49c3cb668e8332fb001b8a7 Mon Sep 17 00:00:00 2001 From: Luigi 'Comio' Mantellini Date: Mon, 8 Sep 2008 02:46:13 +0200 Subject: Add support for LZMA uncompression algorithm. Signed-off-by: Luigi 'Comio' Mantellini Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD --- README | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) (limited to 'README') diff --git a/README b/README index 5135281ddc..a04038567d 100644 --- a/README +++ b/README @@ -1044,6 +1044,29 @@ The following options need to be configured: 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 -- cgit v1.2.3