diff options
| author | Kartik K. Agaram <vc@akkartik.com> | 2021-02-11 00:12:08 -0800 |
|---|---|---|
| committer | Kartik K. Agaram <vc@akkartik.com> | 2021-02-11 00:12:08 -0800 |
| commit | 64a1c141981fbf50167621e3605f0d3344d69ca5 (patch) | |
| tree | 816f07b5c975a1a8b741505a33cbc64434251e83 /baremetal/boot.hex | |
| parent | 4d08e78ed4821037cd1c95b2a978f5c5b03f64fa (diff) | |
| download | mu-64a1c141981fbf50167621e3605f0d3344d69ca5.tar.gz | |
7717 - baremetal: enable FPU (I think)
Diffstat (limited to 'baremetal/boot.hex')
| -rw-r--r-- | baremetal/boot.hex | 19 |
1 files changed, 14 insertions, 5 deletions
diff --git a/baremetal/boot.hex b/baremetal/boot.hex index 4e4222b0..7b29e49f 100644 --- a/baremetal/boot.hex +++ b/baremetal/boot.hex @@ -257,13 +257,22 @@ e9 fd ff # loop forever e6 21 # port 0x21 <- al # 11e: - # initialization is done; enable interrupts - fb - e9 dc 16 00 00 # jump to 0x9400 [label] + fb # enable interrupts + db e3 # initialize FPU + # eax <- cr4 + 0f 20 # copy cr4 to rm32 + e0 # 11/mod/direct 100/r32/CR4 000/rm32/eax + # eax <- or bit 9 + 0f ba + e8 # 11/mod/direct 101/subop/bit-test-and-set 000/rm32/eax + 09 # imm8 + # cr4 <- eax + 0f 22 # copy rm32 to cr4 + e0 # 11/mod/direct 100/r32/CR4 000/rm32/eax + e9 d0 16 00 00 # jump to 0x9400 [label] # padding -# 124: - 00 00 00 00 00 00 00 00 00 00 00 00 +# 130: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |