[POWERPC] Rewrite IO allocation & mapping on powerpc64

This rewrites pretty much from scratch the handling of MMIO and PIO
space allocations on powerpc64.  The main goals are:

 - Get rid of imalloc and use more common code where possible
 - Simplify the current mess so that PIO space is allocated and
   mapped in a single place for PCI bridges
 - Handle allocation constraints of PIO for all bridges including
   hot plugged ones within the 2GB space reserved for IO ports,
   so that devices on hotplugged busses will now work with drivers
   that assume IO ports fit in an int.
 - Cleanup and separate tracking of the ISA space in the reserved
   low 64K of IO space. No ISA -> Nothing mapped there.

I booted a cell blade with IDE on PIO and MMIO and a dual G5 so
far, that's it :-)

With this patch, all allocations are done using the code in
mm/vmalloc.c, though we use the low level __get_vm_area with
explicit start/stop constraints in order to manage separate
areas for vmalloc/vmap, ioremap, and PCI IOs.

This greatly simplifies a lot of things, as you can see in the
diffstat of that patch :-)

A new pair of functions pcibios_map/unmap_io_space() now replace
all of the previous code that used to manipulate PCI IOs space.
The allocation is done at mapping time, which is now called from
scan_phb's, just before the devices are probed (instead of after,
which is by itself a bug fix). The only other caller is the PCI
hotplug code for hot adding PCI-PCI bridges (slots).

imalloc is gone, as is the "sub-allocation" thing, but I do beleive
that hotplug should still work in the sense that the space allocation
is always done by the PHB, but if you unmap a child bus of this PHB
(which seems to be possible), then the code should properly tear
down all the HPTE mappings for that area of the PHB allocated IO space.

I now always reserve the first 64K of IO space for the bridge with
the ISA bus on it. I have moved the code for tracking ISA in a separate
file which should also make it smarter if we ever are capable of
hot unplugging or re-plugging an ISA bridge.

This should have a side effect on platforms like powermac where VGA IOs
will no longer work. This is done on purpose though as they would have
worked semi-randomly before. The idea at this point is to isolate drivers
that might need to access those and fix them by providing a proper
function to obtain an offset to the legacy IOs of a given bus.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

7 files changed, 8 insertions, 90 deletions

diff --git a/arch/powerpc/platforms/cell/io-workarounds.c b/arch/powerpc/platforms/cell/io-workarounds.c
index 7fb92f23f380..9d7c2ef940a8 100644
--- a/arch/powerpc/platforms/cell/io-workarounds.c
+++ b/arch/powerpc/platforms/cell/io-workarounds.c
@@ -102,7 +102,7 @@ static void spider_io_flush(const volatile void __iomem *addr)
                 vaddr = (unsigned long)PCI_FIX_ADDR(addr);
 
                 /* Check if it's in allowed range for  PIO */
-                if (vaddr < PHBS_IO_BASE || vaddr >= IMALLOC_BASE)
+                if (vaddr < PHB_IO_BASE || vaddr > PHB_IO_END)
                         return;
 
                 /* Try to find a PTE. If not, clear the paddr, we'll do
diff --git a/arch/powerpc/platforms/iseries/pci.c b/arch/powerpc/platforms/iseries/pci.c
index 9c974227155e..23d876211874 100644
--- a/arch/powerpc/platforms/iseries/pci.c
+++ b/arch/powerpc/platforms/iseries/pci.c
@@ -742,6 +742,11 @@ void __init iSeries_pcibios_init(void)
         /* Install IO hooks */
         ppc_pci_io = iseries_pci_io;
 
+        /* iSeries has no IO space in the common sense, it needs to set
+         * the IO base to 0
+         */
+        pci_io_base = 0;
+
         if (root == NULL) {
                 printk(KERN_CRIT "iSeries_pcibios_init: can't find root "
                                 "of device tree\n");
diff --git a/arch/powerpc/platforms/maple/pci.c b/arch/powerpc/platforms/maple/pci.c
index 7aaa5bbc9363..f357b9258875 100644
--- a/arch/powerpc/platforms/maple/pci.c
+++ b/arch/powerpc/platforms/maple/pci.c
@@ -519,23 +519,6 @@ void __devinit maple_pci_irq_fixup(struct pci_dev *dev)
         DBG(" <- maple_pci_irq_fixup\n");
 }
 
-static void __init maple_fixup_phb_resources(void)
-{
-        struct pci_controller *hose, *tmp;
-        
-        list_for_each_entry_safe(hose, tmp, &hose_list, list_node) {
-                unsigned long offset = (unsigned long)hose->io_base_virt - pci_io_base;
-
-                hose->io_resource.start += offset;
-                hose->io_resource.end += offset;
-
-                printk(KERN_INFO "PCI Host %d, io start: %llx; io end: %llx\n",
-                       hose->global_number,
-                       (unsigned long long)hose->io_resource.start,
-                       (unsigned long long)hose->io_resource.end);
-        }
-}
-
 void __init maple_pci_init(void)
 {
         struct device_node *np, *root;
@@ -573,24 +556,6 @@ void __init maple_pci_init(void)
         if (ht && add_bridge(ht) != 0)
                 of_node_put(ht);
 
-        /*
-         * We need to call pci_setup_phb_io for the HT bridge first
-         * so it gets the I/O port numbers starting at 0, and we
-         * need to call it for the AGP bridge after that so it gets
-         * small positive I/O port numbers.
-         */
-        if (u3_ht)
-                pci_setup_phb_io(u3_ht, 1);
-        if (u3_agp)
-                pci_setup_phb_io(u3_agp, 0);
-        if (u4_pcie)
-                pci_setup_phb_io(u4_pcie, 0);
-
-        /* Fixup the IO resources on our host bridges as the common code
-         * does it only for childs of the host bridges
-         */
-        maple_fixup_phb_resources();
-
         /* Setup the linkage between OF nodes and PHBs */ 
         pci_devs_phb_init();
 
diff --git a/arch/powerpc/platforms/pasemi/pci.c b/arch/powerpc/platforms/pasemi/pci.c
index bbc6dfcfaa91..5606f25760bc 100644
--- a/arch/powerpc/platforms/pasemi/pci.c
+++ b/arch/powerpc/platforms/pasemi/pci.c
@@ -150,29 +150,11 @@ static int __init add_bridge(struct device_node *dev)
         printk(KERN_INFO "Found PA-PXP PCI host bridge.\n");
 
         /* Interpret the "ranges" property */
-        /* This also maps the I/O region and sets isa_io/mem_base */
         pci_process_bridge_OF_ranges(hose, dev, 1);
-        pci_setup_phb_io(hose, 1);
 
         return 0;
 }
 
-
-static void __init pas_fixup_phb_resources(void)
-{
-        struct pci_controller *hose, *tmp;
-
-        list_for_each_entry_safe(hose, tmp, &hose_list, list_node) {
-                unsigned long offset = (unsigned long)hose->io_base_virt - pci_io_base;
-                hose->io_resource.start += offset;
-                hose->io_resource.end += offset;
-                printk(KERN_INFO "PCI Host %d, io start: %lx; io end: %lx\n",
-                       hose->global_number,
-                       hose->io_resource.start, hose->io_resource.end);
-        }
-}
-
-
 void __init pas_pci_init(void)
 {
         struct device_node *np, *root;
@@ -190,8 +172,6 @@ void __init pas_pci_init(void)
 
         of_node_put(root);
 
-        pas_fixup_phb_resources();
-
         /* Setup the linkage between OF nodes and PHBs */
         pci_devs_phb_init();
 
diff --git a/arch/powerpc/platforms/powermac/pci.c b/arch/powerpc/platforms/powermac/pci.c
index c4af9e21ac93..8302e34a3cbf 100644
--- a/arch/powerpc/platforms/powermac/pci.c
+++ b/arch/powerpc/platforms/powermac/pci.c
@@ -1006,19 +1006,6 @@ void __devinit pmac_pci_irq_fixup(struct pci_dev *dev)
 #endif /* CONFIG_PPC32 */
 }
 
-#ifdef CONFIG_PPC64
-static void __init pmac_fixup_phb_resources(void)
-{
-        struct pci_controller *hose, *tmp;
-
-        list_for_each_entry_safe(hose, tmp, &hose_list, list_node) {
-                printk(KERN_INFO "PCI Host %d, io start: %lx; io end: %lx\n",
-                       hose->global_number,
-                       hose->io_resource.start, hose->io_resource.end);
-        }
-}
-#endif
-
 void __init pmac_pci_init(void)
 {
         struct device_node *np, *root;
@@ -1053,25 +1040,6 @@ void __init pmac_pci_init(void)
         if (ht && add_bridge(ht) != 0)
                 of_node_put(ht);
 
-        /*
-         * We need to call pci_setup_phb_io for the HT bridge first
-         * so it gets the I/O port numbers starting at 0, and we
-         * need to call it for the AGP bridge after that so it gets
-         * small positive I/O port numbers.
-         */
-        if (u3_ht)
-                pci_setup_phb_io(u3_ht, 1);
-        if (u3_agp)
-                pci_setup_phb_io(u3_agp, 0);
-        if (u4_pcie)
-                pci_setup_phb_io(u4_pcie, 0);
-
-        /*
-         * On ppc64, fixup the IO resources on our host bridges as
-         * the common code does it only for children of the host bridges
-         */
-        pmac_fixup_phb_resources();
-
         /* Setup the linkage between OF nodes and PHBs */
         pci_devs_phb_init();
 
diff --git a/arch/powerpc/platforms/pseries/pci_dlpar.c b/arch/powerpc/platforms/pseries/pci_dlpar.c
index 0b113ab90ba9..47f0e0857f0e 100644
--- a/arch/powerpc/platforms/pseries/pci_dlpar.c
+++ b/arch/powerpc/platforms/pseries/pci_dlpar.c
@@ -202,8 +202,6 @@ struct pci_controller * __devinit init_phb_dynamic(struct device_node *dn)
         rtas_setup_phb(phb);
         pci_process_bridge_OF_ranges(phb, dn, 0);
 
-        pci_setup_phb_io_dynamic(phb, primary);
-
         pci_devs_phb_init_dynamic(phb);
 
         if (dn->child)
diff --git a/arch/powerpc/platforms/pseries/pseries.h b/arch/powerpc/platforms/pseries/pseries.h
index 2729d559fd91..61e19f78b923 100644
--- a/arch/powerpc/platforms/pseries/pseries.h
+++ b/arch/powerpc/platforms/pseries/pseries.h
@@ -33,6 +33,8 @@ static inline void setup_kexec_cpu_down_xics(void) { }
 static inline void setup_kexec_cpu_down_mpic(void) { }
 #endif
 
+extern void pSeries_final_fixup(void);
+
 /* Poweron flag used for enabling auto ups restart */
 extern unsigned long rtas_poweron_auto;