sparc32,leon: added LEON-common low-level PCI routines

The LEON architecture does not have a BIOS or bootloader that
initializes PCI for us, instead Linux generic PCI layer is used
to set up resources and IRQ.

Signed-off-by: Daniel Hellstrom <daniel@gaisler.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 254 insertions, 0 deletions

diff --git a/arch/sparc/kernel/Makefile b/arch/sparc/kernel/Makefile
index 59a2256aee38..b02d2e3f36bc 100644
--- a/arch/sparc/kernel/Makefile
+++ b/arch/sparc/kernel/Makefile
@@ -74,6 +74,7 @@ obj-$(CONFIG_SPARC64_SMP) += cpumap.o
 obj-y                     += dma.o
 
 obj-$(CONFIG_PCIC_PCI)    += pcic.o
+obj-$(CONFIG_LEON_PCI)    += leon_pci.o
 
 obj-$(CONFIG_SMP)         += trampoline_$(BITS).o smp_$(BITS).o
 obj-$(CONFIG_SPARC32_SMP) += sun4m_smp.o sun4d_smp.o leon_smp.o
diff --git a/arch/sparc/kernel/leon_pci.c b/arch/sparc/kernel/leon_pci.c
new file mode 100644
index 000000000000..a8a9a275037d
--- /dev/null
+++ b/arch/sparc/kernel/leon_pci.c
@@ -0,0 +1,253 @@
+/*
+ * leon_pci.c: LEON Host PCI support
+ *
+ * Copyright (C) 2011 Aeroflex Gaisler AB, Daniel Hellstrom
+ *
+ * Code is partially derived from pcic.c
+ */
+
+#include <linux/of_device.h>
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <asm/leon.h>
+#include <asm/leon_pci.h>
+
+/* The LEON architecture does not rely on a BIOS or bootloader to setup
+ * PCI for us. The Linux generic routines are used to setup resources,
+ * reset values of confuration-space registers settings ae preseved.
+ */
+void leon_pci_init(struct platform_device *ofdev, struct leon_pci_info *info)
+{
+        struct pci_bus *root_bus;
+
+        root_bus = pci_scan_bus_parented(&ofdev->dev, 0, info->ops, info);
+        if (root_bus) {
+                root_bus->resource[0] = &info->io_space;
+                root_bus->resource[1] = &info->mem_space;
+                root_bus->resource[2] = NULL;
+
+                /* Init all PCI devices into PCI tree */
+                pci_bus_add_devices(root_bus);
+
+                /* Setup IRQs of all devices using custom routines */
+                pci_fixup_irqs(pci_common_swizzle, info->map_irq);
+
+                /* Assign devices with resources */
+                pci_assign_unassigned_resources();
+        }
+}
+
+/* PCI Memory and Prefetchable Memory is direct-mapped. However I/O Space is
+ * accessed through a Window which is translated to low 64KB in PCI space, the
+ * first 4KB is not used so 60KB is available.
+ *
+ * This function is used by generic code to translate resource addresses into
+ * PCI addresses.
+ */
+void pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
+                             struct resource *res)
+{
+        struct leon_pci_info *info = dev->bus->sysdata;
+
+        region->start = res->start;
+        region->end = res->end;
+
+        if (res->flags & IORESOURCE_IO) {
+                region->start -= (info->io_space.start - 0x1000);
+                region->end -= (info->io_space.start - 0x1000);
+        }
+}
+EXPORT_SYMBOL(pcibios_resource_to_bus);
+
+/* see pcibios_resource_to_bus() comment */
+void pcibios_bus_to_resource(struct pci_dev *dev, struct resource *res,
+                             struct pci_bus_region *region)
+{
+        struct leon_pci_info *info = dev->bus->sysdata;
+
+        res->start = region->start;
+        res->end = region->end;
+
+        if (res->flags & IORESOURCE_IO) {
+                res->start += (info->io_space.start - 0x1000);
+                res->end += (info->io_space.start - 0x1000);
+        }
+}
+EXPORT_SYMBOL(pcibios_bus_to_resource);
+
+void __devinit pcibios_fixup_bus(struct pci_bus *pbus)
+{
+        struct leon_pci_info *info = pbus->sysdata;
+        struct pci_dev *dev;
+        int i, has_io, has_mem;
+        u16 cmd;
+
+        /* Generic PCI bus probing sets these to point at
+         * &io{port,mem}_resouce which is wrong for us.
+         */
+        if (pbus->self == NULL) {
+                pbus->resource[0] = &info->io_space;
+                pbus->resource[1] = &info->mem_space;
+                pbus->resource[2] = NULL;
+        }
+
+        list_for_each_entry(dev, &pbus->devices, bus_list) {
+                /*
+                 * We can not rely on that the bootloader has enabled I/O
+                 * or memory access to PCI devices. Instead we enable it here
+                 * if the device has BARs of respective type.
+                 */
+                has_io = has_mem = 0;
+                for (i = 0; i < PCI_ROM_RESOURCE; i++) {
+                        unsigned long f = dev->resource[i].flags;
+                        if (f & IORESOURCE_IO)
+                                has_io = 1;
+                        else if (f & IORESOURCE_MEM)
+                                has_mem = 1;
+                }
+                /* ROM BARs are mapped into 32-bit memory space */
+                if (dev->resource[PCI_ROM_RESOURCE].end != 0) {
+                        dev->resource[PCI_ROM_RESOURCE].flags |=
+                                                        IORESOURCE_ROM_ENABLE;
+                        has_mem = 1;
+                }
+                pci_bus_read_config_word(pbus, dev->devfn, PCI_COMMAND, &cmd);
+                if (has_io && !(cmd & PCI_COMMAND_IO)) {
+#ifdef CONFIG_PCI_DEBUG
+                        printk(KERN_INFO "LEONPCI: Enabling I/O for dev %s\n",
+                                         pci_name(dev));
+#endif
+                        cmd |= PCI_COMMAND_IO;
+                        pci_bus_write_config_word(pbus, dev->devfn, PCI_COMMAND,
+                                                                        cmd);
+                }
+                if (has_mem && !(cmd & PCI_COMMAND_MEMORY)) {
+#ifdef CONFIG_PCI_DEBUG
+                        printk(KERN_INFO "LEONPCI: Enabling MEMORY for dev"
+                                         "%s\n", pci_name(dev));
+#endif
+                        cmd |= PCI_COMMAND_MEMORY;
+                        pci_bus_write_config_word(pbus, dev->devfn, PCI_COMMAND,
+                                                                        cmd);
+                }
+        }
+}
+
+/*
+ * Other archs parse arguments here.
+ */
+char * __devinit pcibios_setup(char *str)
+{
+        return str;
+}
+
+resource_size_t pcibios_align_resource(void *data, const struct resource *res,
+                                resource_size_t size, resource_size_t align)
+{
+        return res->start;
+}
+
+int pcibios_enable_device(struct pci_dev *dev, int mask)
+{
+        return pci_enable_resources(dev, mask);
+}
+
+struct device_node *pci_device_to_OF_node(struct pci_dev *pdev)
+{
+        /*
+         * Currently the OpenBoot nodes are not connected with the PCI device,
+         * this is because the LEON PROM does not create PCI nodes. Eventually
+         * this will change and the same approach as pcic.c can be used to
+         * match PROM nodes with pci devices.
+         */
+        return NULL;
+}
+EXPORT_SYMBOL(pci_device_to_OF_node);
+
+void __devinit pcibios_update_irq(struct pci_dev *dev, int irq)
+{
+#ifdef CONFIG_PCI_DEBUG
+        printk(KERN_DEBUG "LEONPCI: Assigning IRQ %02d to %s\n", irq,
+                pci_name(dev));
+#endif
+        pci_write_config_byte(dev, PCI_INTERRUPT_LINE, irq);
+}
+
+/* in/out routines taken from pcic.c
+ *
+ * This probably belongs here rather than ioport.c because
+ * we do not want this crud linked into SBus kernels.
+ * Also, think for a moment about likes of floppy.c that
+ * include architecture specific parts. They may want to redefine ins/outs.
+ *
+ * We do not use horrible macros here because we want to
+ * advance pointer by sizeof(size).
+ */
+void outsb(unsigned long addr, const void *src, unsigned long count)
+{
+        while (count) {
+                count -= 1;
+                outb(*(const char *)src, addr);
+                src += 1;
+                /* addr += 1; */
+        }
+}
+EXPORT_SYMBOL(outsb);
+
+void outsw(unsigned long addr, const void *src, unsigned long count)
+{
+        while (count) {
+                count -= 2;
+                outw(*(const short *)src, addr);
+                src += 2;
+                /* addr += 2; */
+        }
+}
+EXPORT_SYMBOL(outsw);
+
+void outsl(unsigned long addr, const void *src, unsigned long count)
+{
+        while (count) {
+                count -= 4;
+                outl(*(const long *)src, addr);
+                src += 4;
+                /* addr += 4; */
+        }
+}
+EXPORT_SYMBOL(outsl);
+
+void insb(unsigned long addr, void *dst, unsigned long count)
+{
+        while (count) {
+                count -= 1;
+                *(unsigned char *)dst = inb(addr);
+                dst += 1;
+                /* addr += 1; */
+        }
+}
+EXPORT_SYMBOL(insb);
+
+void insw(unsigned long addr, void *dst, unsigned long count)
+{
+        while (count) {
+                count -= 2;
+                *(unsigned short *)dst = inw(addr);
+                dst += 2;
+                /* addr += 2; */
+        }
+}
+EXPORT_SYMBOL(insw);
+
+void insl(unsigned long addr, void *dst, unsigned long count)
+{
+        while (count) {
+                count -= 4;
+                /*
+                 * XXX I am sure we are in for an unaligned trap here.
+                 */
+                *(unsigned long *)dst = inl(addr);
+                dst += 4;
+                /* addr += 4; */
+        }
+}
+EXPORT_SYMBOL(insl);