m68k: common PCI support definitions and code

Basic set of definitions and support code required to turn on CONFIG_PCI
for the m68k architecture. Nothing specific to any PCI implementation in
any m68k class CPU hardware yet.

Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>

5 files changed, 122 insertions, 0 deletions

diff --git a/arch/m68k/include/asm/dma.h b/arch/m68k/include/asm/dma.h
index 947064184639..0ff3fc6a6d9a 100644
--- a/arch/m68k/include/asm/dma.h
+++ b/arch/m68k/include/asm/dma.h
@@ -488,6 +488,10 @@ static __inline__ int get_dma_residue(unsigned int dmanr)
 extern int request_dma(unsigned int dmanr, const char * device_id);     /* reserve a DMA channel */
 extern void free_dma(unsigned int dmanr);       /* release it again */
 
+#ifdef CONFIG_PCI
+extern int isa_dma_bridge_buggy;
+#else
 #define isa_dma_bridge_buggy    (0)
+#endif
 
 #endif /* _M68K_DMA_H */
diff --git a/arch/m68k/include/asm/io_mm.h b/arch/m68k/include/asm/io_mm.h
index fa4324bcf566..b85dbef85e1c 100644
--- a/arch/m68k/include/asm/io_mm.h
+++ b/arch/m68k/include/asm/io_mm.h
@@ -340,4 +340,6 @@ static inline void memcpy_toio(volatile void __iomem *dst, const void *src, int
  */
 #define xlate_dev_kmem_ptr(p)   p
 
+#define ioport_map(port, nr)    ((void __iomem *)(port))
+
 #endif /* _IO_H */
diff --git a/arch/m68k/include/asm/pci.h b/arch/m68k/include/asm/pci.h
index 4ad0aea48ab4..848c3dfaad50 100644
--- a/arch/m68k/include/asm/pci.h
+++ b/arch/m68k/include/asm/pci.h
@@ -2,6 +2,7 @@
 #define _ASM_M68K_PCI_H
 
 #include <asm-generic/pci-dma-compat.h>
+#include <asm-generic/pci.h>
 
 /* The PCI address space does equal the physical memory
  * address space.  The networking and block device layers use
@@ -9,4 +10,9 @@
  */
 #define PCI_DMA_BUS_IS_PHYS     (1)
 
+#define pcibios_assign_all_busses()     1
+
+#define PCIBIOS_MIN_IO          0x00000100
+#define PCIBIOS_MIN_MEM         0x02000000
+
 #endif /* _ASM_M68K_PCI_H */
diff --git a/arch/m68k/kernel/Makefile b/arch/m68k/kernel/Makefile
index 5c7070e21eb7..068ad49210d6 100644
--- a/arch/m68k/kernel/Makefile
+++ b/arch/m68k/kernel/Makefile
@@ -18,6 +18,7 @@ obj-y	+= setup.o signal.o sys_m68k.o syscalltable.o time.o traps.o
 
 obj-$(CONFIG_MMU_MOTOROLA) += ints.o vectors.o
 obj-$(CONFIG_MMU_SUN3) += ints.o vectors.o
+obj-$(CONFIG_PCI) += pcibios.o
 
 ifndef CONFIG_MMU_SUN3
 obj-y   += dma.o
diff --git a/arch/m68k/kernel/pcibios.c b/arch/m68k/kernel/pcibios.c
new file mode 100644
index 000000000000..b2988aa1840b
--- /dev/null
+++ b/arch/m68k/kernel/pcibios.c
@@ -0,0 +1,109 @@
+/*
+ * pci.c -- basic PCI support code
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ *
+ * (C) Copyright 2011, Greg Ungerer <gerg@uclinux.org>
+ */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/mm.h>
+#include <linux/init.h>
+#include <linux/pci.h>
+
+/*
+ * From arch/i386/kernel/pci-i386.c:
+ *
+ * We need to avoid collisions with `mirrored' VGA ports
+ * and other strange ISA hardware, so we always want the
+ * addresses to be allocated in the 0x000-0x0ff region
+ * modulo 0x400.
+ *
+ * Why? Because some silly external IO cards only decode
+ * the low 10 bits of the IO address. The 0x00-0xff region
+ * is reserved for motherboard devices that decode all 16
+ * bits, so it's ok to allocate at, say, 0x2800-0x28ff,
+ * but we want to try to avoid allocating at 0x2900-0x2bff
+ * which might be mirrored at 0x0100-0x03ff..
+ */
+resource_size_t pcibios_align_resource(void *data, const struct resource *res,
+        resource_size_t size, resource_size_t align)
+{
+        resource_size_t start = res->start;
+
+        if ((res->flags & IORESOURCE_IO) && (start & 0x300))
+                start = (start + 0x3ff) & ~0x3ff;
+
+        start = (start + align - 1) & ~(align - 1);
+
+        return start;
+}
+
+/*
+ * This is taken from the ARM code for this.
+ */
+int pcibios_enable_device(struct pci_dev *dev, int mask)
+{
+        struct resource *r;
+        u16 cmd, newcmd;
+        int idx;
+
+        pci_read_config_word(dev, PCI_COMMAND, &cmd);
+        newcmd = cmd;
+
+        for (idx = 0; idx < 6; idx++) {
+                /* Only set up the requested stuff */
+                if (!(mask & (1 << idx)))
+                        continue;
+
+                r = dev->resource + idx;
+                if (!r->start && r->end) {
+                        pr_err(KERN_ERR "PCI: Device %s not available because of resource collisions\n",
+                                pci_name(dev));
+                        return -EINVAL;
+                }
+                if (r->flags & IORESOURCE_IO)
+                        newcmd |= PCI_COMMAND_IO;
+                if (r->flags & IORESOURCE_MEM)
+                        newcmd |= PCI_COMMAND_MEMORY;
+        }
+
+        /*
+         * Bridges (eg, cardbus bridges) need to be fully enabled
+         */
+        if ((dev->class >> 16) == PCI_BASE_CLASS_BRIDGE)
+                newcmd |= PCI_COMMAND_IO | PCI_COMMAND_MEMORY;
+
+
+        if (newcmd != cmd) {
+                pr_info("PCI: enabling device %s (0x%04x -> 0x%04x)\n",
+                        pci_name(dev), cmd, newcmd);
+                pci_write_config_word(dev, PCI_COMMAND, newcmd);
+        }
+        return 0;
+}
+
+void pcibios_update_irq(struct pci_dev *dev, int irq)
+{
+        pci_write_config_byte(dev, PCI_INTERRUPT_LINE, irq);
+}
+
+void __devinit pcibios_fixup_bus(struct pci_bus *bus)
+{
+        struct pci_dev *dev;
+
+        list_for_each_entry(dev, &bus->devices, bus_list) {
+                pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, 8);
+                pci_write_config_byte(dev, PCI_LATENCY_TIMER, 32);
+        }
+}
+
+char __devinit *pcibios_setup(char *str)
+{
+        return str;
+}
+