diff options
author | Markus Armbruster <armbru@redhat.com> | 2012-08-15 13:12:20 +0200 |
---|---|---|
committer | Blue Swirl <blauwirbel@gmail.com> | 2012-08-18 16:54:23 +0000 |
commit | e89001f72edde37fb36fa7c964daa1bbeb2eca26 (patch) | |
tree | 16f7686100516d64117a63fe4926a147f8085e3c | |
parent | ff961015529437f4b83fca0a92069aebcf533c9c (diff) |
pc: Fix RTC CMOS info on RAM for ram_size < 1MiB
pc_cmos_init() always claims 640KiB base memory, and ram_size - 1MiB
extended memory. The latter can underflow to "lots of extended
memory". Fix both, and clean up some.
Note: SeaBIOS currently requires 1MiB of RAM, and doesn't check
whether it got enough.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
-rw-r--r-- | hw/pc.c | 31 |
1 files changed, 18 insertions, 13 deletions
@@ -338,32 +338,37 @@ void pc_cmos_init(ram_addr_t ram_size, ram_addr_t above_4g_mem_size, /* various important CMOS locations needed by PC/Bochs bios */ /* memory size */ - val = 640; /* base memory in K */ + /* base memory (first MiB) */ + val = MIN(ram_size / 1024, 640); rtc_set_memory(s, 0x15, val); rtc_set_memory(s, 0x16, val >> 8); - - val = (ram_size / 1024) - 1024; + /* extended memory (next 64MiB) */ + if (ram_size > 1024 * 1024) { + val = (ram_size - 1024 * 1024) / 1024; + } else { + val = 0; + } if (val > 65535) val = 65535; rtc_set_memory(s, 0x17, val); rtc_set_memory(s, 0x18, val >> 8); rtc_set_memory(s, 0x30, val); rtc_set_memory(s, 0x31, val >> 8); - - if (above_4g_mem_size) { - rtc_set_memory(s, 0x5b, (unsigned int)above_4g_mem_size >> 16); - rtc_set_memory(s, 0x5c, (unsigned int)above_4g_mem_size >> 24); - rtc_set_memory(s, 0x5d, (uint64_t)above_4g_mem_size >> 32); - } - - if (ram_size > (16 * 1024 * 1024)) - val = (ram_size / 65536) - ((16 * 1024 * 1024) / 65536); - else + /* memory between 16MiB and 4GiB */ + if (ram_size > 16 * 1024 * 1024) { + val = (ram_size - 16 * 1024 * 1024) / 65536; + } else { val = 0; + } if (val > 65535) val = 65535; rtc_set_memory(s, 0x34, val); rtc_set_memory(s, 0x35, val >> 8); + /* memory above 4GiB */ + val = above_4g_mem_size / 65536; + rtc_set_memory(s, 0x5b, val); + rtc_set_memory(s, 0x5c, val >> 8); + rtc_set_memory(s, 0x5d, val >> 16); /* set the number of CPU */ rtc_set_memory(s, 0x5f, smp_cpus - 1); |