[POWERPC] Celleb: bug fix caused by not casting pointer types

This fixes a bug caused by changes of pointer type in
commit f1fda89522c5aaa1bd4ef69605e85e6ee9c85faf.

hose->cfg_addr type is "volatile unsigned int __iomem *", so
"hose->cfg_addr + X" will not make an intended address.

This patch also adds comments for usage of cfg_addr and cfg_data in
pci_controller structure.  We use them in irregular way, and the
original code is short of explanations about them.

Signed-off-by: Kou Ishizaki <kou.ishizaki@toshiba.co.jp>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

diff --git a/arch/powerpc/platforms/celleb/scc_epci.c b/arch/powerpc/platforms/celleb/scc_epci.c
index c11b39c3776a5565848a4e3c8d723cb314316579..fb23d53eb09c53cce17482905f95169c266de9b0 100644 (file)
--- a/arch/powerpc/platforms/celleb/scc_epci.c
+++ b/arch/powerpc/platforms/celleb/scc_epci.c
@@ -43,11 +43,34 @@
 
 #define iob()  __asm__ __volatile__("eieio; sync":::"memory")
 
+static inline volatile void __iomem *celleb_epci_get_epci_base(
+                                       struct pci_controller *hose)
+{
+       /*
+        * Note:
+        * Celleb epci uses cfg_addr as a base address for
+        * epci control registers.
+        */
+
+       return hose->cfg_addr;
+}
+
+static inline volatile void __iomem *celleb_epci_get_epci_cfg(
+                                       struct pci_controller *hose)
+{
+       /*
+        * Note:
+        * Celleb epci uses cfg_data as a base address for
+        * configuration area for epci devices.
+        */
+
+       return hose->cfg_data;
+}
 
 #if 0 /* test code for epci dummy read */
 static void celleb_epci_dummy_read(struct pci_dev *dev)
 {
-       void __iomem *epci_base;
+       volatile void __iomem *epci_base;
        struct device_node *node;
        struct pci_controller *hose;
        u32 val;
@@ -58,7 +81,7 @@ static void celleb_epci_dummy_read(struct pci_dev *dev)
        if (!hose)
                return;
 
-       epci_base = hose->cfg_addr;
+       epci_base = celleb_epci_get_epci_base(hose);
 
        val = in_be32(epci_base + SCC_EPCI_WATRP);
        iosync();
@@ -70,19 +93,20 @@ static void celleb_epci_dummy_read(struct pci_dev *dev)
 static inline void clear_and_disable_master_abort_interrupt(
                                        struct pci_controller *hose)
 {
-       void __iomem *addr;
-       addr = hose->cfg_addr + PCI_COMMAND;
-       out_be32(addr, in_be32(addr) | (PCI_STATUS_REC_MASTER_ABORT << 16));
+       volatile void __iomem *epci_base, *reg;
+       epci_base = celleb_epci_get_epci_base(hose);
+       reg = epci_base + PCI_COMMAND;
+       out_be32(reg, in_be32(reg) | (PCI_STATUS_REC_MASTER_ABORT << 16));
 }
 
 static int celleb_epci_check_abort(struct pci_controller *hose,
-                                  void __iomem *addr)
+                                  volatile void __iomem *addr)
 {
-       void __iomem *reg, *epci_base;
+       volatile void __iomem *reg, *epci_base;
        u32 val;
 
        iob();
-       epci_base = hose->cfg_addr;
+       epci_base = celleb_epci_get_epci_base(hose);
 
        reg = epci_base + PCI_COMMAND;
        val = in_be32(reg);
@@ -108,20 +132,21 @@ static int celleb_epci_check_abort(struct pci_controller *hose,
        return PCIBIOS_SUCCESSFUL;
 }
 
-static void __iomem *celleb_epci_make_config_addr(struct pci_controller *hose,
+static volatile void __iomem *celleb_epci_make_config_addr(
+                                       struct pci_controller *hose,
                                        unsigned int devfn, int where)
 {
-       void __iomem *addr;
+       volatile void __iomem *addr;
        struct pci_bus *bus = hose->bus;
 
        if (bus->self)
-               addr = hose->cfg_data +
+               addr = celleb_epci_get_epci_cfg(hose) +
                       (((bus->number & 0xff) << 16)
                        | ((devfn & 0xff) << 8)
                        | (where & 0xff)
                        | 0x01000000);
        else
-               addr = hose->cfg_data +
+               addr = celleb_epci_get_epci_cfg(hose) +
                       (((devfn & 0xff) << 8) | (where & 0xff));
 
        pr_debug("EPCI: config_addr = 0x%p\n", addr);
@@ -132,7 +157,7 @@ static void __iomem *celleb_epci_make_config_addr(struct pci_controller *hose,
 static int celleb_epci_read_config(struct pci_bus *bus,
                        unsigned int devfn, int where, int size, u32 * val)
 {
-       void __iomem *addr;
+       volatile void __iomem *epci_base, *addr;
        struct device_node *node;
        struct pci_controller *hose;
 
@@ -142,13 +167,14 @@ static int celleb_epci_read_config(struct pci_bus *bus,
        node = (struct device_node *)bus->sysdata;
        hose = pci_find_hose_for_OF_device(node);
 
-       if (!hose->cfg_data)
+       if (!celleb_epci_get_epci_cfg(hose))
                return PCIBIOS_DEVICE_NOT_FOUND;
 
        if (bus->number == hose->first_busno && devfn == 0) {
                /* EPCI controller self */
 
-               addr = hose->cfg_addr + where;
+               epci_base = celleb_epci_get_epci_base(hose);
+               addr = epci_base + where;
 
                switch (size) {
                case 1:
@@ -185,7 +211,7 @@ static int celleb_epci_read_config(struct pci_bus *bus,
        }
 
        pr_debug("EPCI: "
-                "addr=0x%lx, devfn=0x%x, where=0x%x, size=0x%x, val=0x%x\n",
+                "addr=0x%p, devfn=0x%x, where=0x%x, size=0x%x, val=0x%x\n",
                 addr, devfn, where, size, *val);
 
        return celleb_epci_check_abort(hose, NULL);
@@ -194,7 +220,7 @@ static int celleb_epci_read_config(struct pci_bus *bus,
 static int celleb_epci_write_config(struct pci_bus *bus,
                        unsigned int devfn, int where, int size, u32 val)
 {
-       void __iomem *addr;
+       volatile void __iomem *epci_base, *addr;
        struct device_node *node;
        struct pci_controller *hose;
 
@@ -204,13 +230,15 @@ static int celleb_epci_write_config(struct pci_bus *bus,
        node = (struct device_node *)bus->sysdata;
        hose = pci_find_hose_for_OF_device(node);
 
-       if (!hose->cfg_data)
+
+       if (!celleb_epci_get_epci_cfg(hose))
                return PCIBIOS_DEVICE_NOT_FOUND;
 
        if (bus->number == hose->first_busno && devfn == 0) {
                /* EPCI controller self */
 
-               addr = hose->cfg_addr + where;
+               epci_base = celleb_epci_get_epci_base(hose);
+               addr = epci_base + where;
 
                switch (size) {
                case 1:
@@ -258,10 +286,10 @@ struct pci_ops celleb_epci_ops = {
 static int __devinit celleb_epci_init(struct pci_controller *hose)
 {
        u32 val;
-       void __iomem *reg, *epci_base;
+       volatile void __iomem *reg, *epci_base;
        int hwres = 0;
 
-       epci_base = hose->cfg_addr;
+       epci_base = celleb_epci_get_epci_base(hose);
 
        /* PCI core reset(Internal bus and PCI clock) */
        reg = epci_base + SCC_EPCI_CKCTRL;
@@ -382,6 +410,18 @@ int __devinit celleb_setup_epci(struct device_node *node,
 
        pr_debug("PCI: celleb_setup_epci()\n");
 
+       /*
+        * Note:
+        * Celleb epci uses cfg_addr and cfg_data member of
+        * pci_controller structure in irregular way.
+        *
+        * cfg_addr is used to map for control registers of
+        * celleb epci.
+        *
+        * cfg_data is used for configuration area of devices
+        * on Celleb epci buses.
+        */
+
        if (of_address_to_resource(node, 0, &r))
                goto error;
        hose->cfg_addr = ioremap(r.start, (r.end - r.start + 1));