Gather information about the mappable regions of the card at

attach time.  Allow access to these regions in vga_pci_mmap().

Note: we also have to allow access to the legacy ISA "hole" in
vga_pci_mmap(), since the X server needs to be able to read
the legacy BIOS on many cards.

XXX Need to address the PCI Expansion ROM.

Based on changes from Simon Burge <simonb@wasabisystems.com>.

sys/dev/pci/vga_pci.c

@@ -1,4 +1,4 @@
-/* $NetBSD: vga_pci.c,v 1.6 2001/09/14 06:46:08 thorpej Exp $ */
+/* $NetBSD: vga_pci.c,v 1.7 2001/09/14 16:54:20 thorpej Exp $ */
 
 /*
  * Copyright (c) 1995, 1996 Carnegie-Mellon University.
@@ -44,14 +44,28 @@
 #include <dev/ic/vgavar.h>
 #include <dev/pci/vga_pcivar.h>
 
+#include <dev/isa/isareg.h>	/* For legacy VGA address ranges */
+
 #include <dev/wscons/wsconsio.h>
 #include <dev/wscons/wsdisplayvar.h>
 
+#define	NBARS		6	/* number of PCI BARs */
+
+struct vga_bar {
+	bus_addr_t vb_base;
+	bus_size_t vb_size;
+	pcireg_t vb_type;
+	int vb_flags;
+};
+
 struct vga_pci_softc {
 	struct vga_softc sc_vga;
 
 	pci_chipset_tag_t sc_pc;
 	pcitag_t sc_pcitag;
+
+	struct vga_bar sc_bars[NBARS];
+	struct vga_bar sc_rom;
 };
 
 int	vga_pci_match __P((struct device *, struct cfdata *, void *));
@@ -122,6 +136,7 @@ vga_pci_attach(parent, self, aux)
 	struct vga_softc *sc = &psc->sc_vga;
 	struct pci_attach_args *pa = aux;
 	char devinfo[256];
+	int bar, reg;
 
 	psc->sc_pc = pa->pa_pc;
 	psc->sc_pcitag = pa->pa_tag;
@@ -130,6 +145,36 @@ vga_pci_attach(parent, self, aux)
 	printf(": %s (rev. 0x%02x)\n", devinfo,
 	    PCI_REVISION(pa->pa_class));
 
+	/*
+	 * Gather info about all the BARs.  These are used to allow
+	 * the X server to map the VGA device.
+	 */
+	for (bar = 0; bar < NBARS; bar++) {
+		reg = PCI_MAPREG_START + (bar * 4);
+		psc->sc_bars[bar].vb_type = pci_mapreg_type(psc->sc_pc,
+		    psc->sc_pcitag, reg);
+		if (PCI_MAPREG_TYPE(psc->sc_bars[bar].vb_type) ==
+		    PCI_MAPREG_TYPE_IO) {
+			/* Don't bother fetching I/O BARs. */
+			continue;
+		}
+		if (PCI_MAPREG_MEM_TYPE(psc->sc_bars[bar].vb_type) ==
+		    PCI_MAPREG_MEM_TYPE_64BIT) {
+			/* XXX */
+			printf("%s: WARNING: ignoring 64-bit BAR @ 0x%02x\n",
+			    sc->sc_dev.dv_xname, reg);
+			continue;
+		}
+		/* Ignore errors (unimplemented BARs). */
+		(void) pci_mapreg_info(psc->sc_pc, psc->sc_pcitag, reg,
+		     psc->sc_bars[bar].vb_type,
+		     &psc->sc_bars[bar].vb_base,
+		     &psc->sc_bars[bar].vb_size,
+		     &psc->sc_bars[bar].vb_flags);
+	}
+
+	/* XXX Expansion ROM? */
+
 	vga_common_attach(sc, pa->pa_iot, pa->pa_memt, WSDISPLAY_TYPE_PCIVGA,
 	    &vga_pci_funcs);
 }
@@ -164,7 +209,36 @@ vga_pci_ioctl(void *v, u_long cmd, caddr_t data, int flag, struct proc *p)
 paddr_t
 vga_pci_mmap(void *v, off_t offset, int prot)
 {
+	struct vga_config *vc = v;
+	struct vga_pci_softc *psc = (void *) vc->softc;
+	struct vga_bar *vb;
+	int bar;
 
-	/* XXX Fill me in. */
+	for (bar = 0; bar < NBARS; bar++) {
+		vb = &psc->sc_bars[bar];
+		if (vb->vb_size == 0)
+			continue;
+		if (offset >= vb->vb_base &&
+		    offset < (vb->vb_base + vb->vb_size)) {
+			/* XXX This the right thing to do with flags? */
+			return (bus_space_mmap(vc->hdl.vh_memt, vb->vb_base,
+			    (offset - vb->vb_base), prot, vb->vb_flags));
+		}
+	}
+
+	/* XXX Expansion ROM? */
+
+	/*
+	 * Allow mmap access to the legacy ISA hole.  This is where
+	 * the legacy video BIOS will be located, and also where
+	 * the legacy VGA display buffer is located.
+	 *
+	 * XXX Security implications, here?
+	 */
+	if (offset >= IOM_BEGIN && offset < IOM_END)
+		return (bus_space_mmap(vc->hdl.vh_memt, IOM_BEGIN,
+		    (offset - IOM_BEGIN), prot, 0));
+
+	/* Range not found. */
 	return (-1);
 }