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Diffstat (limited to 'arch/powerpc/kernel/isa-bridge.c')
-rw-r--r--arch/powerpc/kernel/isa-bridge.c92
1 files changed, 92 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/isa-bridge.c b/arch/powerpc/kernel/isa-bridge.c
index ae1316106e2b..bb6f8993412e 100644
--- a/arch/powerpc/kernel/isa-bridge.c
+++ b/arch/powerpc/kernel/isa-bridge.c
@@ -29,6 +29,7 @@
#include <asm/pci-bridge.h>
#include <asm/machdep.h>
#include <asm/ppc-pci.h>
+#include <asm/isa-bridge.h>
unsigned long isa_io_base; /* NULL if no ISA bus */
EXPORT_SYMBOL(isa_io_base);
@@ -167,6 +168,97 @@ void __init isa_bridge_find_early(struct pci_controller *hose)
}
/**
+ * isa_bridge_find_early - Find and map the ISA IO space early before
+ * main PCI discovery. This is optionally called by
+ * the arch code when adding PCI PHBs to get early
+ * access to ISA IO ports
+ */
+void __init isa_bridge_init_non_pci(struct device_node *np)
+{
+ const __be32 *ranges, *pbasep = NULL;
+ int rlen, i, rs;
+ u32 na, ns, pna;
+ u64 cbase, pbase, size = 0;
+
+ /* If we already have an ISA bridge, bail off */
+ if (isa_bridge_devnode != NULL)
+ return;
+
+ pna = of_n_addr_cells(np);
+ if (of_property_read_u32(np, "#address-cells", &na) ||
+ of_property_read_u32(np, "#size-cells", &ns)) {
+ pr_warn("ISA: Non-PCI bridge %s is missing address format\n",
+ np->full_name);
+ return;
+ }
+
+ /* Check it's a supported address format */
+ if (na != 2 || ns != 1) {
+ pr_warn("ISA: Non-PCI bridge %s has unsupported address format\n",
+ np->full_name);
+ return;
+ }
+ rs = na + ns + pna;
+
+ /* Grab the ranges property */
+ ranges = of_get_property(np, "ranges", &rlen);
+ if (ranges == NULL || rlen < rs) {
+ pr_warn("ISA: Non-PCI bridge %s has absent or invalid ranges\n",
+ np->full_name);
+ return;
+ }
+
+ /* Parse it. We are only looking for IO space */
+ for (i = 0; (i + rs - 1) < rlen; i += rs) {
+ if (be32_to_cpup(ranges + i) != 1)
+ continue;
+ cbase = be32_to_cpup(ranges + i + 1);
+ size = of_read_number(ranges + i + na + pna, ns);
+ pbasep = ranges + i + na;
+ break;
+ }
+
+ /* Got something ? */
+ if (!size || !pbasep) {
+ pr_warn("ISA: Non-PCI bridge %s has no usable IO range\n",
+ np->full_name);
+ return;
+ }
+
+ /* Align size and make sure it's cropped to 64K */
+ size = PAGE_ALIGN(size);
+ if (size > 0x10000)
+ size = 0x10000;
+
+ /* Map pbase */
+ pbase = of_translate_address(np, pbasep);
+ if (pbase == OF_BAD_ADDR) {
+ pr_warn("ISA: Non-PCI bridge %s failed to translate IO base\n",
+ np->full_name);
+ return;
+ }
+
+ /* We need page alignment */
+ if ((cbase & ~PAGE_MASK) || (pbase & ~PAGE_MASK)) {
+ pr_warn("ISA: Non-PCI bridge %s has non aligned IO range\n",
+ np->full_name);
+ return;
+ }
+
+ /* Got it */
+ isa_bridge_devnode = np;
+
+ /* Set the global ISA io base to indicate we have an ISA bridge
+ * and map it
+ */
+ isa_io_base = ISA_IO_BASE;
+ __ioremap_at(pbase, (void *)ISA_IO_BASE,
+ size, pgprot_val(pgprot_noncached(__pgprot(0))));
+
+ pr_debug("ISA: Non-PCI bridge is %s\n", np->full_name);
+}
+
+/**
* isa_bridge_find_late - Find and map the ISA IO space upon discovery of
* a new ISA bridge
*/