Allocating resources to isab children

[Henrik Brix Andersen]

Hi,

I am writing a driver for the GPIO part of the AMD CS5536 south bridge (isab0), but have encountered a problem with resource allocation.
The GPIO address (0x6100-0x61FF) is available through PCI BAR 1 as seen in the output from pciconf(8):

isab0 at pci0:0:15:0:	class=0x060100 card=0x20901022 chip=0x20901022 rev=0x03 hdr=0x00
    vendor     = 'Advanced Micro Devices (AMD)'
    device     = 'CS5536 [Geode companion] ISA'
    class      = bridge
    subclass   = PCI-ISA
    bar   [10] = type I/O Port, range 32, base 0x6000, size  8, enabled
    bar   [14] = type I/O Port, range 32, base 0x6100, size 256, enabled
    bar   [18] = type I/O Port, range 32, base 0x6200, size 64, enabled
    bar   [20] = type I/O Port, range 32, base 0x9d00, size 128, enabled
    bar   [24] = type I/O Port, range 32, base 0x9c00, size 64, enabled

However, when I try to allocate the I/O port resource in the minimalistic example below, I always get 0x1100-0x1100, not 0x6100-0x61FF?

I have modelled the code after recommendation from John Baldwin in http://lists.freebsd.org/pipermail/freebsd-acpi/2007-August/003964.html but I must be doing something wrong...

Brix



#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/module.h>

#include <dev/pci/pcireg.h>
#include <dev/pci/pcivar.h>

#include <machine/bus.h>
#include <sys/rman.h>
#include <machine/resource.h>

#define	AMD_GEODE_CS5536_DEV_ID	0x20901022

struct test_softc {
	device_t	 dev;
	int		 rid;
	struct resource *res;
};

static void
test_identify(driver_t *driver, device_t parent)
{
	if (device_find_child(parent, driver->name, -1) != NULL)
		return;

	if (pci_get_devid(parent) == AMD_GEODE_CS5536_DEV_ID) {
		if (device_add_child(parent, driver->name, -1) == NULL)
			device_printf(parent, "could not add child\n");
	}
}

static int
test_probe(device_t dev)
{
	device_set_desc(dev, "Test driver");

	return (BUS_PROBE_DEFAULT);
}

static int
test_attach(device_t dev)
{
	struct test_softc *sc;
	int err;

	err = 0;
	sc = device_get_softc(dev);
	sc->dev = dev;

	sc->rid = PCIR_BAR(1);
	sc->res = bus_alloc_resource_any(dev, SYS_RES_IOPORT, &sc->rid,
					 RF_ACTIVE);

	if (sc->res == NULL) {
		device_printf(dev, "could not allocate I/O port\n");
		err = ENXIO;
		goto out;
	}

	/* prints out 0x1100-0x1100 - not 0x6100-0x61FF as expected */
	printf("allocated: 0x%lx-0x%lx\n", rman_get_start(sc->res),
		rman_get_end(sc->res));

out:
	return (err);
}

static int
test_detach(device_t dev)
{
	struct test_softc *sc = device_get_softc(dev);
        int err;

	err = bus_generic_detach(dev);
	if (sc->res != NULL)
		bus_release_resource(dev, SYS_RES_IOPORT, sc->rid, sc->res);

        return (err);
}

static device_method_t test_methods[] = {
	DEVMETHOD(device_identify,	test_identify),
	DEVMETHOD(device_probe,		test_probe),
	DEVMETHOD(device_attach,	test_attach),
	DEVMETHOD(device_detach,	test_detach),

	{ 0, 0 }
};

static driver_t test_driver = {
	"test",
	test_methods,
	sizeof(struct test_softc),
};

static devclass_t test_devclass;

DRIVER_MODULE(test, isab, test_driver, test_devclass, 0, 0);

-- 
Henrik Brix Andersen <brix at FreeBSD.org>



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