failed to initialize Intel 9560 wifi driver

[Wen-Chun KUO]

lwhsu and I are trying to add intel 9560 to iwm(4), the preliminary patch
adds 9000 series firmware module and skeleton is here:

See the raw diff file : https://gist.github.com/lwhsu/
d741b6d5aad582375b1c469753d28c14#file-iwm-9560-diff

But, the driver seems not working.


The first error message we saw is:


`api flags index 1 larger than supported by driver`


We thought that is just a version problem so we bumped the version to avoid
to hit the case.

Still, there are other error messages:


```

iwm0: <Intel(R) Dual Band Wireless AC 9560> mem 0x604c110000-0x604c113fff
at device 20.3 on pci0

iwm0: timeout waiting for clock stabilization

iwm0: apm init error 60

iwm0: could not initialize hardware

```


Tracing the code, it means the driver doesn's receive interrupts to set
"wait_entry->triggered = 1", so the driver fails due to time out.

We checked IRQ and found the IRQ information does not display "iwm0"



Intel 9560:

% vmstat -i

interrupt                          total       rate

irq9: acpi0                            1          0

cpu0:timer                       3314518         12

cpu1:timer                       1617788          6

cpu2:timer                       1560000          6

cpu3:timer                       1539914          6

cpu4:timer                       1560190          6

cpu5:timer                       1548846          6

cpu6:timer                       1602733          6

cpu7:timer                       1693147          6

irq128: xhci0                      91387          0

irq129: ahci0                     306623          1

irq133: hdac0                         36          0

irq134: em0:irq0                  557434          2

Total                           15392617         5


Comparing to Intel 8265 (good example):


 > vmstat -i

interrupt total rate

irq1: atkbd0 49983 2

irq9: acpi0 50686 2

irq12: psm0 227864 11

irq16: vgapci0 743067 36

cpu0:timer 2052123 101

cpu1:timer 1431203 70

cpu2:timer 1482806 73

cpu3:timer 1450326 71

cpu4:timer 1493074 73

cpu5:timer 1451673 71

cpu6:timer 1548006 76

cpu7:timer 1439006 71

irq128: xhci0 37743 2

irq129: iwm0 451303 22  <---- successfully registered

irq130: nvme0 44 0

irq131: nvme0 130357 6

irq132: nvme0 125464 6

irq133: nvme0 128783 6

irq134: nvme0 124244 6

irq135: nvme0 129532 6

irq136: nvme0 126176 6

irq137: nvme0 130928 6

irq138: nvme0 127506 6

irq143: hdac0 17308 1

irq144: em0:irq0 49017 2

Total 14998222 735


Some items we want to clear first


1. We suspect the problem is related to the IRQ that not properly shared
between PCI driver and Intel wireless driver

However, it works in Intel wireless 8265 with similar code. This idea is
still questionable.


2. The Intel wireless contains 2 kernel modules: "iwm9000fw" and "iwm".
"iwm9000fw" is a binary release from Intel and "iwm" is an interface
driver, which registers the IRQ. We are not sure how they co-work. Maybe
the binary iwm9080fw is not correctly installed so the interrupt handler is
not triggered? (The weird thing is the IRQ registering doesn't complain,
but the IRQ information doesn't show the driver)


Another question is, if 2 drivers share an IRQ, what would "vmstat -i" look
like? These drivers would use the same IRQ value?


3. We are looking at the difference between 8000 and 9000 firmware
initialization in Linux. We also curious about the precedence in "irq
register" and "firmware"