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10:06:46
froggey
fitzsim: oh well, thanks for trying
14:34:41
fitzsim
I'm trying to dump the HPET configuration from the GRUB prompt
14:34:50
fitzsim
I found the ACPI HPET table entry
14:35:09
fitzsim
(this is in QEMU q35 for now, then I'll try on real hardware)
14:35:42
fitzsim
General Capabilities and ID Register: 01 00 00 00 80 00 00 00
14:35:51
fitzsim
does that look reasonable?
14:36:19
fitzsim
I'm trying to orient myself in these big structures
14:43:13
fitzsim
struct hpet : public description_table_header
14:43:39
fitzsim
that should mean that hardware_rev_id follows directly after creator_revision in memory?
14:45:02
fitzsim
pci_vendor_id: 0x86 0x80
14:45:09
fitzsim
I think that means Intel so makes sense...
14:46:24
fitzsim
hmm, address_structure address is where it stops making sense
14:48:06
fitzsim
00 00 00 00 00 00 d0 fe 00 00 00 00
14:48:25
fitzsim
that would make register_bit_width 00 which doesn't seem right
14:50:14
froggey
that's probably fine as it's pointing to a device, not a specific register in it
14:50:40
froggey
it should be at 0xfed00000, based on that
14:50:45
froggey
which seems pretty reasonable
14:51:31
fitzsim
dumping 8 bytes there gives: 01 00 00 00 80 00 00 00
14:54:57
fitzsim
many subsequent bytes are 00
14:56:12
froggey
ah, it might be because you're doing byte reads
14:56:30
froggey
you need to do 32-bit reads on these registers
14:59:46
fitzsim
seems that legacy replacement mapping is disabled
15:00:33
fitzsim
I'll do the same check on the hardware later
15:03:11
froggey
what's the value of configuration register for timers 0 & 1? offsets 0x100 and 0x120