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Re: x86 pcitag_t change proposal/patch



On Thu, Dec 06, 2012 at 10:21:41AM -0600, Jonathan A. Kollasch wrote:
> +
> +union pci_conf_selector {
> +     pci_conf_selector_t selector;
> +     struct {
> +             uint32_t address;
> +     } mode1;
> +     struct {
> +             uint16_t port;
> +             uint8_t enable;
> +             uint8_t forward;
> +     } mode2;
> +};

Given the code, you should be able to do it without the union.
(By just shifting/masking to convert the subfields to an integer.)
Even that might be pointless, since the 32bit structure will be
passed by value in a register (on most modern ABI).

        David

-- 
David Laight: david%l8s.co.uk@localhost


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