Any gain to supporting only a single PCMCIA slot?

Any gain to supporting only a single PCMCIA slot?

[steve.snyder]

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Hello.

PCMCIA/Cardbus controllers typically (always?) support 2 slots, and system 
resources are allocated to support those slots.  When you build PCMCIA 
support into your kernel, you are implicitly asking for both slots to be 
supported.  I'm wondering if it would be worthwhile to let the user opt out of 
supporting one of the slots.  

Compaq, in their finite wisdom, only provides a single Type2 Cardbus slot 
on my Presario 1260 notebook.  The controller (a TI PCI1131, see below) 
can handle 2 slots, of course, but only a single physical connector is 
present on this machine.  Therefore I will never get the use of half of 
the controller, including the I/O address, etc. that the kernel has 
allocated for it.  

Would it be worth the savings in system resources to allow support for 
only a single slot?

Thank you.

-----------------------------------------------------------

# cat /proc/iomem
00000000-0009f7ff : System RAM
0009f800-0009ffff : reserved
000a0000-000bffff : Video RAM area
000c0000-000c7fff : Video ROM
000f0000-000fffff : System ROM
00100000-09ffffff : System RAM
  00100000-001d1aad : Kernel code
  001d1aae-0021083f : Kernel data
10000000-10000fff : Texas Instruments PCI1131
10001000-10001fff : Texas Instruments PCI1131 (#2)
10400000-107fffff : PCI CardBus #01
  10400000-1041ffff : PCI device 10b7:6564
10800000-10bfffff : PCI CardBus #01
  10800000-1080007f : PCI device 10b7:6564
  10800080-108000ff : PCI device 10b7:6564
  10800100-108001ff : PCI device 10b7:6565
  10800200-1080027f : PCI device 10b7:6565
10c00000-10ffffff : PCI CardBus #05
11000000-113fffff : PCI CardBus #05
fd000000-fdffffff : Neomagic Corporation NM2160 [MagicGraph 128XD]
fea00000-febfffff : Neomagic Corporation NM2160 [MagicGraph 128XD]
fecff000-fecfffff : OPTi Inc. 82C861
fed00000-fedfffff : Neomagic Corporation NM2160 [MagicGraph 128XD]

Re: Any gain to supporting only a single PCMCIA slot?

[Pavel Machek]

Hi!

> PCMCIA/Cardbus controllers typically (always?) support 2 slots, and system 
> resources are allocated to support those slots.  When you build PCMCIA 
> support into your kernel, you are implicitly asking for both slots to be 
> supported.  I'm wondering if it would be worthwhile to let the user opt out of 
> supporting one of the slots.  
> 
> Compaq, in their finite wisdom, only provides a single Type2 Cardbus slot 
> on my Presario 1260 notebook.  The controller (a TI PCI1131, see below) 
> can handle 2 slots, of course, but only a single physical connector is 
> present on this machine.  Therefore I will never get the use of half of 
> the controller, including the I/O address, etc. that the kernel has 
> allocated for it.  

> Would it be worth the savings in system resources to allow support for 
> only a single slot?

Probably not.

								Pavel
-- 
I'm pavel@ucw.cz. "In my country we have almost anarchy and I don't care."
Panos Katsaloulis describing me w.r.t. patents at discuss@linmodems.org