Re: [PATCH V2] ARM: NUC900: Add PCI driver support for NUC960

From: Russell King - ARM Linux
Date: Tue Nov 15 2011 - 12:30:43 EST


On Mon, Nov 14, 2011 at 03:13:31PM +0800, Wan ZongShun wrote:
> +#define NUC900_PCI_MEM_BASE 0xC0000000
> +#define NUC900_PCI_MEM_END 0xDFFFEFFFF
> +#define NUC900_PCI_MEM_SIZE 0x20000000

NUC900_PCI_MEM_END has more than 32 bits.

> +#define NUC900_PCI_IO_BASE 0xE0000000
> +#define NUC900_PCI_IO_END 0xE000FFFF
> +#define NUC900_PCI_IO_SIZE 0x10000
...
> +static struct resource pci_io = {
> + .name = "NUC900 PCI IO",
> + .start = NUC900_PCI_IO_BASE,
> + .end = NUC900_PCI_IO_BASE + NUC900_PCI_IO_SIZE - 1,
> + .flags = IORESOURCE_IO,
> +};
...
> +static int __init pci_nuc900_setup_resources(struct resource **resource)
> +{
> + int ret = 0;
> +
> + ret = request_resource(&ioport_resource, &pci_io);
> + if (ret) {
> + pr_err("%s: failed to request resources: %d\n", __func__, ret);
> + goto out;
> + }
...
> + /*
> + * bus->resource[0] is the IO resource for this bus
> + * bus->resource[1] is the mem resource for this bus
> + * bus->resource[2] is the prefetch mem resource for this bus
> + */
> + resource[0] = &pci_io;
> + resource[1] = &pci_mem;
> + resource[2] = NULL;

This is better, but still not correct.

1. in mach/io.h:

-#define IO_SPACE_LIMIT 0xffffffff
+#define IO_SPACE_LIMIT 0xffff

-#define __io(a) __typesafe_io(a)
+#define __io(a) ((void __iomem __force *)(a) + VA_OF_IO_SPACE)

where VA_OF_IO_SPACE is correctly named and typed.

2. set resource[0] = &ioport_resource and get rid of pci_io entirely.

3. if (!request_mem_region(PA_OF_IO_SPACE, 64K, "PCI IO emulation space"))
pr_warn("Unable to request PCI IO space\n");
in your pre-init function.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/