[PATCH 1/4] m68k: common PCI support definitions and code

gerg
2012-06-29T05:19:41Z

From: Greg Ungerer <gerg@uclinux.org>

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 harwdare yet.

Signed-off-by: Greg Ungerer <gerg@uclinux.org>
---
arch/m68k/include/asm/dma.h | 4 ++
arch/m68k/include/asm/io_mm.h | 2 +
arch/m68k/include/asm/pci.h | 6 ++
arch/m68k/kernel/Makefile | 1 +
arch/m68k/kernel/pcibios.c | 109 +++++++++++++++++++++++++++++++++++++++++
drivers/pci/Makefile | 1 +
6 files changed, 123 insertions(+), 0 deletions(-)
create mode 100644 arch/m68k/kernel/pcibios.c

diff --git a/arch/m68k/include/asm/dma.h b/arch/m68k/include/asm/dma.h
index 6fbdfe8..7a59439 100644
--- a/arch/m68k/include/asm/dma.h
+++ b/arch/m68k/include/asm/dma.h
@@ -486,6 +486,10 @@ 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 fa4324b..b85dbef 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 4ad0aea..848c3df 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 5c7070e..068ad49 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 0000000..b2988aa
--- /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;
+}
+
diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile
index 01c001f..8d688b2 100644
--- a/drivers/pci/Makefile
+++ b/drivers/pci/Makefile
@@ -49,6 +49,7 @@ obj-$(CONFIG_MN10300) += setup-bus.o
obj-$(CONFIG_MICROBLAZE) += setup-bus.o
obj-$(CONFIG_TILE) += setup-bus.o setup-irq.o
obj-$(CONFIG_SPARC_LEON) += setup-bus.o setup-irq.o
+obj-$(CONFIG_M68K) += setup-bus.o setup-irq.o

#
# ACPI Related PCI FW Functions
--
1.7.0.4