Re: [PATCH] ALPHA: support graphics on non-zero PCI domains (take 2)

From: Sam Ravnborg
Date: Sun Apr 15 2007 - 05:00:47 EST


> +#ifdef CONFIG_VGA_HOSE
> /*
> - * Adjust the addr.
> + * Adjust the address and hose, if necessary.
> */
> -#ifdef CONFIG_VGA_HOSE
> - if (pci_vga_hose && __titan_is_mem_vga(addr)) {
> + if (pci_vga_hose && __is_mem_vga(addr)) {
> h = pci_vga_hose->index;

This code snippet is used in two places.
A better approach would be to define a small inline function
that is empty in the NON HOSe case to avod the ifdefs in the
code logic.


> +tsunami_ioremap(unsigned long addr, unsigned long size)
> +{
> + FIXUP_MEMADDR_VGA(addr);
> + return (void __iomem *)(addr + TSUNAMI_MEM_BIAS);
> +}
> +
> +#ifndef CONFIG_ALPHA_GENERIC
> +EXPORT_SYMBOL(tsunami_ioportmap);
> +EXPORT_SYMBOL(tsunami_ioremap);
> +#endif

It looks strange that the function is always defined but conditionally exported.
Also usual style is to place EXPORT right after closing brace of function -
(with no empty lines in-between).

> +
> +static void __init
> +tsunami_init_vga_hose(void)
> +{
> +#ifdef CONFIG_VGA_HOSE
> + u64 *pu64 = (u64 *)((u64)hwrpb + hwrpb->ctbt_offset);
> +
> + if (pu64[7] == 3) { /* TERM_TYPE == graphics */
> + struct pci_controller *hose;
> + int h = (pu64[30] >> 24) & 0xff; /* console hose # */
> +
> + /*
> + * Our hose numbering does NOT match the console's, so find
> + * the right one...
> + */
> + for (hose = hose_head; hose; hose = hose->next) {
> + if (hose->index == h) break;
> + }
> +
> + if (hose) {
> + printk("Console graphics on hose %d\n", h);
> + pci_vga_hose = hose;
> + }
> + }
> +#endif /* CONFIG_VGA_HOSE */
> +}

Again - avoid ifdef in code.
Surround whole function with ifdef and then provide an empty inline for the NON hose case.

> +/* console.c */
> +#ifdef CONFIG_VGA_HOSE
> +extern void locate_and_init_vga(void *(*)(void *, void *));
> +#else
> +#define locate_and_init_vga() do { } while (0)
> +#endif
static inline would give you a limited type check of arguments.

>
> +config VGA_HOSE
> + bool "VGA on arbitrary hose"
> + depends on ALPHA_GENERIC || ALPHA_TITAN || ALPHA_MARVEL || ALPHA_TSUNAMI
> + default y

Please always include help entry for visible symbols.
You have it mostly written up in the changelog so it should be trivial to add.

Sam
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