Re: [RFC PATCH] PCI: remove access to pci_[enable|disable]_msi() for drivers - take 2

[Roland Dreier <roland@topspin.com>]

    Andi> x86-64 will eventually too, I definitely plan for it at some
    Andi> point.  We need it for very big machines where 255 interrupt
    Andi> vectors are not enough. And as you say with MSI-X it becomes
    Andi> even more important.

MSI-X already works fine on x86-64.  For example, on the machine I'm
sending this from, an Athlon64 system with Nforce 4 (and yes I am
using IP-over-InfiniBand as the only network connection on my workstation):

    $ arch
    x86_64

    $ cat /proc/interrupts 
               CPU0       
      0: 1340159746    IO-APIC-edge  timer
      7:          2    IO-APIC-edge  parport0
      8:          0    IO-APIC-edge  rtc
      9:          0   IO-APIC-level  acpi
     15:   13333990    IO-APIC-edge  ide1
     50:          3       PCI-MSI-X  ib_mthca (async)
     58:     480844       PCI-MSI-X  ib_mthca (cmd)
    177:    7975072   IO-APIC-level  libata, NVidia CK804
    185:    2093654   IO-APIC-level  libata
    193:   14304257   IO-APIC-level  nvidia
    201:     769996   IO-APIC-level  ohci_hcd
    209:          2   IO-APIC-level  ehci_hcd
    217:          3   IO-APIC-level  ohci1394
    233:   37917879       PCI-MSI-X  ib_mthca (comp)
    NMI:     148617 
    LOC: 1340049308 
    ERR:          0
    MIS:          0

    $ lspci
    0000:00:00.0 Memory controller: nVidia Corporation CK804 Memory Controller (rev a3)
    0000:00:01.0 ISA bridge: nVidia Corporation: Unknown device 0050 (rev a3)
    0000:00:01.1 SMBus: nVidia Corporation CK804 SMBus (rev a2)
    0000:00:02.0 USB Controller: nVidia Corporation CK804 USB Controller (rev a2)
    0000:00:02.1 USB Controller: nVidia Corporation CK804 USB Controller (rev a3)
    0000:00:04.0 Multimedia audio controller: nVidia Corporation CK804 AC'97 Audio Controller (rev a2)
    0000:00:06.0 IDE interface: nVidia Corporation CK804 IDE (rev a2)
    0000:00:07.0 IDE interface: nVidia Corporation CK804 Serial ATA Controller (rev a3)
    0000:00:08.0 IDE interface: nVidia Corporation CK804 Serial ATA Controller (rev a3)
    0000:00:09.0 PCI bridge: nVidia Corporation CK804 PCI Bridge (rev a2)
    0000:00:0a.0 Bridge: nVidia Corporation CK804 Ethernet Controller (rev a3)
    0000:00:0b.0 PCI bridge: nVidia Corporation CK804 PCIE Bridge (rev a3)
    0000:00:0c.0 PCI bridge: nVidia Corporation CK804 PCIE Bridge (rev a3)
    0000:00:0d.0 PCI bridge: nVidia Corporation CK804 PCIE Bridge (rev a3)
    0000:00:0e.0 PCI bridge: nVidia Corporation CK804 PCIE Bridge (rev a3)
    0000:00:18.0 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] HyperTransport Technology Configuration
    0000:00:18.1 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] Address Map
    0000:00:18.2 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] DRAM Controller
    0000:00:18.3 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] Miscellaneous Control
    0000:01:00.0 VGA compatible controller: nVidia Corporation: Unknown device 0140 (rev a2)
    0000:03:00.0 InfiniBand: Mellanox Technologies MT25208 InfiniHost III Ex (rev a0)
    0000:05:0b.0 FireWire (IEEE 1394): Texas Instruments TSB43AB22/A IEEE-1394a-2000 Controller (PHY/Link)
    0000:05:0c.0 Ethernet controller: Marvell Technology Group Ltd. Gigabit Ethernet Controller (rev 13)

    $ cat /proc/cpuinfo 
    processor	: 0
    vendor_id	: AuthenticAMD
    cpu family	: 15
    model		: 31
    model name	: AMD Athlon(tm) 64 Processor 3500+
    stepping	: 0
    cpu MHz		: 1005.169
    cache size	: 512 KB
    fpu		: yes
    fpu_exception	: yes
    cpuid level	: 1
    wp		: yes
    flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 pni syscall nx mmxext fxsr_opt lm 3dnowext 3dnow lahf_lm
    bogomips	: 1988.42
    TLB size	: 1088 4K pages
    clflush size	: 64
    cache_alignment	: 64
    address sizes	: 40 bits physical, 48 bits virtual
    power management: ts fid vid ttp