So, I think I've confirmed your suspicion. I booted Linux Mint with a
4.10 kernel, and I see that the RTC took 0x70, and I don't see any
watchdog listed at all.
mint@mint ~ $ uname -a
Linux mint 4.10.0-38-generic #42~16.04.1-Ubuntu SMP Tue Oct 10 16:32:20
UTC 2017 x86_64 x86_64 x86_64 GNU/Linux
mint@mint ~ $ sudo cat /proc/ioports
0000-0cf7 : PCI Bus 0000:00
0000-001f : dma1
0020-0021 : pic1
0040-0043 : timer0
0050-0053 : timer1
0060-0060 : keyboard
0062-0062 : PNP0C09:00
0062-0062 : EC data
0064-0064 : keyboard
0066-0066 : PNP0C09:00
0066-0066 : EC cmd
0070-0077 : rtc0
0080-008f : dma page reg
00a0-00a1 : pic2
00c0-00df : dma2
00f0-00ff : fpu
0680-069f : pnp 00:00
0cf8-0cff : PCI conf1
0d00-ffff : PCI Bus 0000:00
164e-164f : pnp 00:00
1800-18fe : pnp 00:00
1800-1803 : ACPI PM1a_EVT_BLK
1804-1805 : ACPI PM1a_CNT_BLK
1808-180b : ACPI PM_TMR
1810-1815 : ACPI CPU throttle
1850-1850 : ACPI PM2_CNT_BLK
1854-1857 : pnp 00:02
1880-189f : ACPI GPE0_BLK
3000-3fff : PCI Bus 0000:01
3000-30ff : 0000:01:00.0
3000-30ff : r8169
4000-403f : 0000:00:02.0
4040-405f : 0000:00:1f.3
4060-407f : 0000:00:1f.2
4060-407f : ahci
4080-4087 : 0000:00:1f.2
4080-4087 : ahci
4088-408f : 0000:00:1f.2
4088-408f : ahci
4090-4093 : 0000:00:1f.2
4090-4093 : ahci
4094-4097 : 0000:00:1f.2
4094-4097 : ahci
ffff-ffff : pnp 00:00
ffff-ffff : pnp 00:00
ffff-ffff : pnp 00:00
mint@mint ~ $ sudo cat /proc/iomem
00000000-00000fff : reserved
00001000-0006efff : System RAM
0006f000-0006ffff : reserved
00070000-00087fff : System RAM
00088000-000bffff : reserved
000a0000-000bffff : PCI Bus 0000:00
000c0000-000c3fff : PCI Bus 0000:00
000c4000-000c7fff : PCI Bus 0000:00
000c8000-000cbfff : PCI Bus 0000:00
000cc000-000cffff : PCI Bus 0000:00
000d0000-000d3fff : PCI Bus 0000:00
000d4000-000d7fff : PCI Bus 0000:00
000d8000-000dbfff : PCI Bus 0000:00
000dc000-000dffff : PCI Bus 0000:00
000f0000-000fffff : System ROM
00100000-a56affff : System RAM
a56b0000-a5eaffff : reserved
a5eb0000-aa6befff : System RAM
aa6bf000-aa8befff : reserved
aa8bf000-aaebefff : reserved
aaebf000-aafbefff : ACPI Non-volatile Storage
aafbf000-aaffefff : ACPI Tables
aafff000-aaffffff : System RAM
ab000000-af9fffff : reserved
aba00000-af9fffff : Graphics Stolen Memory
afa00000-feafffff : PCI Bus 0000:00
afa10000-afa1ffff : pnp 00:05
afa20000-afa20fff : pnp 00:05
b0000000-bfffffff : 0000:00:02.0
c0000000-c03fffff : 0000:00:02.0
c0400000-c04fffff : PCI Bus 0000:02
c0400000-c0401fff : 0000:02:00.0
c0400000-c0401fff : iwlwifi
c0500000-c05fffff : PCI Bus 0000:01
c0500000-c0503fff : 0000:01:00.0
c0500000-c0503fff : r8169
c0504000-c0504fff : 0000:01:00.0
c0504000-c0504fff : r8169
c0600000-c060ffff : 0000:00:14.0
c0600000-c060ffff : xhci-hcd
c0610000-c0613fff : 0000:00:03.0
c0610000-c0613fff : ICH HD audio
c0614000-c0617fff : 0000:00:1b.0
c0614000-c0617fff : ICH HD audio
c0618000-c061801f : 0000:00:16.0
c0618000-c061801f : mei_me
c0619000-c06190ff : 0000:00:1f.3
c061b000-c061b7ff : 0000:00:1f.2
c061b000-c061b7ff : ahci
c061c000-c061c3ff : 0000:00:1d.0
c061c000-c061c3ff : ehci_hcd
e0000000-efffffff : PCI MMCONFIG 0000 [bus 00-ff]
e0000000-efffffff : reserved
e0000000-efffffff : pnp 00:05
fe101000-fe112fff : reserved
feb00000-feb0ffff : reserved
fec00000-fec00fff : reserved
fec00000-fec003ff : IOAPIC 0
fed00000-fee00fff : reserved
fed00000-fed003ff : HPET 0
fed00000-fed003ff : PNP0103:00
fed10000-fed17fff : pnp 00:05
fed18000-fed18fff : pnp 00:05
fed19000-fed19fff : pnp 00:05
fed1c000-fed1ffff : pnp 00:05
fed20000-fed3ffff : pnp 00:05
fed90000-fed93fff : pnp 00:05
fee00000-fee00fff : Local APIC
ff000000-ffffffff : INT0800:00
ffc00000-ffffffff : reserved
100000000-44f5fffff : System RAM
1b6400000-1b6cdb828 : Kernel code
1b6cdb829-1b73a0fbf : Kernel data
1b75d8000-1b7826fff : Kernel bss
44f600000-44fffffff : RAM buffer
On 02/13/2018 08:45 PM, Alexandre Belloni wrote:
On 13/02/2018 at 18:56:34 -0500, Peter Milley wrote:
Okay, I've booted the new kernel.
peter@haven:~$ uname -a
Linux haven 4.16.0-rc1+ #32 SMP Tue Feb 13 22:11:39 CET 2018 x86_64
x86_64 x86_64 GNU/Linux
peter@haven:~$ dmesg | grep -i rtc
[ 0.045403] RTC time: 23:46:52, date: 02/13/18
[ 1.368198] rtc_cmos 00:01: RTC can wake from S4
[ 1.368205] rtc_cmos: drivers/rtc/rtc-cmos.c +679 cmos_do_probe
[ 1.368235] rtc_cmos: drivers/rtc/rtc-cmos.c +684 cmos_do_probe
[ 1.368260] rtc_cmos: drivers/rtc/rtc-cmos.c +688 cmos_do_probe
[ 1.368285] rtc_cmos: 1: 70 8
[ 1.368302] rtc_cmos: probe of 00:01 failed with error -16
[ 1.408861] hctosys: unable to open rtc device (rtc0)
[...]
And /proc/ioports:
peter@haven:~$ sudo cat /proc/ioports
0000-0cf7 : PCI Bus 0000:00
0000-001f : dma1
0020-0021 : pic1
0040-0043 : timer0
0050-0053 : timer1
0060-0060 : keyboard
0062-0062 : PNP0C09:00
0062-0062 : EC data
0064-0064 : keyboard
0066-0066 : PNP0C09:00
0066-0066 : EC cmd
0070-0072 : wdat_wdt
So I can tell you what is happening but I can't tell you why. You have a
watchdog at 0x70 (size 2) and the RTC at 0x70 (size 8).
Because the watchdog driver is probed first and it requests the io
region, when the RTC driver is probed, it fails to request the same
region.
Maybe your 4.10 kernel didn't have CONFIG_WDAT_WDT (this appeared in
4.9).
I'm afraid, that is as far as I can help, you'd have to ask someone that
is more knowledgeable about x86 to go further (I've added the wdat_wdt
driver author in Cc).
