[RFC PATCH] MIPS: PCI: add a map_irq callback to struct pci_controller

[Manuel Lauss <manuel.lauss@googlemail.com>]

I'm rewriting the Alchemy PCI driver to be a platform driver, and
one thing that bugs me to no end is that for every PCI controller
the same global pcibios_map_irq function is called.
Instead I'd like to pass the per-board pci irq tables through
platform data and provide a per-controller map_irq callback.

This patch adds a maq_irq callback to struct pci_controller,
and uses it if available in pcibios_init().

Run-tested on a DB1500 board.

Comments welcome!

Signed-off-by: Manuel Lauss <manuel.lauss@googlemail.com>
---

Eventually I'd like to do this also with pcibios_plat_dev_init,
which is unused except on octeon and SSB-bus BCM chips.

 arch/mips/alchemy/common/pci.c                   |    8 ++++++++
 arch/mips/alchemy/devboards/db1x00/board_setup.c |    8 ++++----
 arch/mips/include/asm/pci.h                      |    2 ++
 arch/mips/pci/fixup-au1000.c                     |    4 +---
 arch/mips/pci/pci.c                              |    9 ++++++---
 5 files changed, 21 insertions(+), 10 deletions(-)

diff --git a/arch/mips/alchemy/common/pci.c b/arch/mips/alchemy/common/pci.c
index 7866cf5..e7bd034 100644
--- a/arch/mips/alchemy/common/pci.c
+++ b/arch/mips/alchemy/common/pci.c
@@ -53,10 +53,18 @@ static struct resource pci_mem_resource = {
 
 extern struct pci_ops au1x_pci_ops;
 
+extern char irq_tab_alchemy[][5];
+
+int alchemy_pci_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
+{
+       return irq_tab_alchemy[slot][pin];
+}
+
 static struct pci_controller au1x_controller = {
        .pci_ops        = &au1x_pci_ops,
        .io_resource    = &pci_io_resource,
        .mem_resource   = &pci_mem_resource,
+       .map_irq        = alchemy_pci_map_irq,
 };
 
 #if defined(CONFIG_SOC_AU1500) || defined(CONFIG_SOC_AU1550)
diff --git a/arch/mips/alchemy/devboards/db1x00/board_setup.c 
b/arch/mips/alchemy/devboards/db1x00/board_setup.c
index 5c956fe..8f6b926 100644
--- a/arch/mips/alchemy/devboards/db1x00/board_setup.c
+++ b/arch/mips/alchemy/devboards/db1x00/board_setup.c
@@ -41,7 +41,7 @@
 #include <prom.h>
 
 #ifdef CONFIG_MIPS_DB1500
-char irq_tab_alchemy[][5] __initdata = {
+char irq_tab_alchemy[][5] = {
        [12] = { -1, AU1500_PCI_INTA, 0xff, 0xff, 0xff }, /* IDSEL 12 - HPT371  
 */
        [13] = { -1, AU1500_PCI_INTA, AU1500_PCI_INTB, AU1500_PCI_INTC, 
AU1500_PCI_INTD }, /* IDSEL 13 - PCI slot */
 };
@@ -50,7 +50,7 @@ char irq_tab_alchemy[][5] __initdata = {
 
 
 #ifdef CONFIG_MIPS_DB1550
-char irq_tab_alchemy[][5] __initdata = {
+char irq_tab_alchemy[][5] = {
        [11] = { -1, AU1550_PCI_INTC, 0xff, 0xff, 0xff }, /* IDSEL 11 - 
on-board HPT371 */
        [12] = { -1, AU1550_PCI_INTB, AU1550_PCI_INTC, AU1550_PCI_INTD, 
AU1550_PCI_INTA }, /* IDSEL 12 - PCI slot 2 (left) */
        [13] = { -1, AU1550_PCI_INTA, AU1550_PCI_INTB, AU1550_PCI_INTC, 
AU1550_PCI_INTD }, /* IDSEL 13 - PCI slot 1 (right) */
@@ -59,7 +59,7 @@ char irq_tab_alchemy[][5] __initdata = {
 
 
 #ifdef CONFIG_MIPS_BOSPORUS
-char irq_tab_alchemy[][5] __initdata = {
+char irq_tab_alchemy[][5] = {
        [11] = { -1, AU1500_PCI_INTA, AU1500_PCI_INTB, 0xff, 0xff }, /* IDSEL 
11 - miniPCI  */
        [12] = { -1, AU1500_PCI_INTA, 0xff, 0xff, 0xff }, /* IDSEL 12 - SN1741  
 */
        [13] = { -1, AU1500_PCI_INTA, AU1500_PCI_INTB, AU1500_PCI_INTC, 
AU1500_PCI_INTD }, /* IDSEL 13 - PCI slot */
@@ -91,7 +91,7 @@ const char *get_system_type(void)
 
 
 #ifdef CONFIG_MIPS_MIRAGE
-char irq_tab_alchemy[][5] __initdata = {
+char irq_tab_alchemy[][5] = {
        [11] = { -1, AU1500_PCI_INTD, 0xff, 0xff, 0xff }, /* IDSEL 11 - SMI VGX 
*/
        [12] = { -1, 0xff, 0xff, AU1500_PCI_INTC, 0xff }, /* IDSEL 12 - PNX1300 
*/
        [13] = { -1, AU1500_PCI_INTA, AU1500_PCI_INTB, 0xff, 0xff }, /* IDSEL 
13 - miniPCI */
diff --git a/arch/mips/include/asm/pci.h b/arch/mips/include/asm/pci.h
index 576397c..a5d30ef 100644
--- a/arch/mips/include/asm/pci.h
+++ b/arch/mips/include/asm/pci.h
@@ -45,6 +45,8 @@ struct pci_controller {
           of the PCI controller */
        int (*get_busno)(void);
        void (*set_busno)(int busno);
+
+       int (*map_irq)(const struct pci_dev *dev, u8 slot, u8 pin);
 };
 
 /*
diff --git a/arch/mips/pci/fixup-au1000.c b/arch/mips/pci/fixup-au1000.c
index e2ddfc4..448d8e5 100644
--- a/arch/mips/pci/fixup-au1000.c
+++ b/arch/mips/pci/fixup-au1000.c
@@ -29,11 +29,9 @@
 #include <linux/pci.h>
 #include <linux/init.h>
 
-extern char irq_tab_alchemy[][5];
-
 int __init pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
 {
-       return irq_tab_alchemy[slot][pin];
+       return -1;
 }
 
 /* Do platform specific device initialization at pci_enable_device() time */
diff --git a/arch/mips/pci/pci.c b/arch/mips/pci/pci.c
index 33bba7b..74f62e4 100644
--- a/arch/mips/pci/pci.c
+++ b/arch/mips/pci/pci.c
@@ -154,10 +154,13 @@ static int __init pcibios_init(void)
        struct pci_controller *hose;
 
        /* Scan all of the recorded PCI controllers.  */
-       for (hose = hose_head; hose; hose = hose->next)
+       for (hose = hose_head; hose; hose = hose->next) {
                pcibios_scanbus(hose);
-
-       pci_fixup_irqs(pci_common_swizzle, pcibios_map_irq);
+               if (hose->map_irq)
+                       pci_fixup_irqs(pci_common_swizzle, hose->map_irq);
+               else
+                       pci_fixup_irqs(pci_common_swizzle, pcibios_map_irq);
+       }
 
        pci_initialized = 1;
 
-- 
1.7.6