[PATCH] ARM: 2693/1: Add PCI support for Versatile/PB

Patch from Catalin Marinas

This patch adds PCI support for the Versatile PB926 platform.

Signed-off-by: Colin King
Signed-off-by: Catalin Marinas
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mach-versatile/pci.c b/arch/arm/mach-versatile/pci.c
new file mode 100644
index 0000000..d1565e8
--- /dev/null
+++ b/arch/arm/mach-versatile/pci.c
@@ -0,0 +1,360 @@
+/*
+ *  linux/arch/arm/mach-versatile/pci.c
+ *
+ * (C) Copyright Koninklijke Philips Electronics NV 2004. All rights reserved.
+ * You can redistribute and/or modify this software under the terms of version 2
+ * of the GNU General Public License as published by the Free Software Foundation.
+ * THIS SOFTWARE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY; WITHOUT EVEN THE IMPLIED
+ * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * Koninklijke Philips Electronics nor its subsidiaries is obligated to provide any support for this software.
+ *
+ * ARM Versatile PCI driver.
+ *
+ * 14/04/2005 Initial version, colin.king@philips.com
+ *
+ */
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/ptrace.h>
+#include <linux/slab.h>
+#include <linux/ioport.h>
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+#include <linux/init.h>
+
+#include <asm/hardware.h>
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/system.h>
+#include <asm/mach/pci.h>
+#include <asm/mach-types.h>
+
+/*
+ * these spaces are mapped using the following base registers:
+ *
+ * Usage Local Bus Memory         Base/Map registers used
+ *
+ * Mem   50000000 - 5FFFFFFF      LB_BASE0/LB_MAP0,  non prefetch
+ * Mem   60000000 - 6FFFFFFF      LB_BASE1/LB_MAP1,  prefetch
+ * IO    44000000 - 4FFFFFFF      LB_BASE2/LB_MAP2,  IO
+ * Cfg   42000000 - 42FFFFFF	  PCI config
+ *
+ */
+#define SYS_PCICTL			IO_ADDRESS(VERSATILE_SYS_PCICTL)
+#define PCI_IMAP0			IO_ADDRESS(VERSATILE_PCI_CORE_BASE+0x0)
+#define PCI_IMAP1			IO_ADDRESS(VERSATILE_PCI_CORE_BASE+0x4)
+#define PCI_IMAP2			IO_ADDRESS(VERSATILE_PCI_CORE_BASE+0x8)
+#define PCI_SMAP0			IO_ADDRESS(VERSATILE_PCI_CORE_BASE+0x10)
+#define PCI_SMAP1			IO_ADDRESS(VERSATILE_PCI_CORE_BASE+0x14)
+#define PCI_SMAP2			IO_ADDRESS(VERSATILE_PCI_CORE_BASE+0x18)
+#define PCI_SELFID			IO_ADDRESS(VERSATILE_PCI_CORE_BASE+0xc)
+
+#define DEVICE_ID_OFFSET		0x00
+#define CSR_OFFSET			0x04
+#define CLASS_ID_OFFSET			0x08
+
+#define VP_PCI_DEVICE_ID		0x030010ee
+#define VP_PCI_CLASS_ID			0x0b400000
+
+static unsigned long pci_slot_ignore = 0;
+
+static int __init versatile_pci_slot_ignore(char *str)
+{
+	int retval;
+	int slot;
+
+	while ((retval = get_option(&str,&slot))) {
+		if ((slot < 0) || (slot > 31)) {
+			printk("Illegal slot value: %d\n",slot);
+		} else {
+			pci_slot_ignore |= (1 << slot);
+		}
+	}
+	return 1;
+}
+
+__setup("pci_slot_ignore=", versatile_pci_slot_ignore);
+
+
+static unsigned long __pci_addr(struct pci_bus *bus,
+				unsigned int devfn, int offset)
+{
+	unsigned int busnr = bus->number;
+
+	/*
+	 * Trap out illegal values
+	 */
+	if (offset > 255)
+		BUG();
+	if (busnr > 255)
+		BUG();
+	if (devfn > 255)
+		BUG();
+
+	return (VERSATILE_PCI_CFG_VIRT_BASE | (busnr << 16) |
+		(PCI_SLOT(devfn) << 11) | (PCI_FUNC(devfn) << 8) | offset);
+}
+
+static int versatile_read_config(struct pci_bus *bus, unsigned int devfn, int where,
+				 int size, u32 *val)
+{
+	unsigned long addr = __pci_addr(bus, devfn, where);
+	u32 v;
+	int slot = PCI_SLOT(devfn);
+
+	if (pci_slot_ignore & (1 << slot)) {
+		/* Ignore this slot */
+		switch (size) {
+		case 1:
+			v = 0xff;
+			break;
+		case 2:
+			v = 0xffff;
+			break;
+		default:
+			v = 0xffffffff;
+		}
+	} else {
+		switch (size) {
+		case 1:
+			addr &= ~3;
+			v = __raw_readb(addr);
+			break;
+
+		case 2:
+			v = __raw_readl(addr & ~3);
+			if (addr & 2) v >>= 16;
+ 			v &= 0xffff;
+			break;
+
+		default:
+			addr &= ~3;
+			v = __raw_readl(addr);
+			break;
+		}
+	}
+
+	*val = v;
+	return PCIBIOS_SUCCESSFUL;
+}
+
+static int versatile_write_config(struct pci_bus *bus, unsigned int devfn, int where,
+				  int size, u32 val)
+{
+	unsigned long addr = __pci_addr(bus, devfn, where);
+	int slot = PCI_SLOT(devfn);
+
+	if (pci_slot_ignore & (1 << slot)) {
+		return PCIBIOS_SUCCESSFUL;
+	}
+
+	switch (size) {
+	case 1:
+		__raw_writeb((u8)val, addr);
+		break;
+
+	case 2:
+		__raw_writew((u16)val, addr);
+		break;
+
+	case 4:
+		__raw_writel(val, addr);
+		break;
+	}
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+static struct pci_ops pci_versatile_ops = {
+	.read	= versatile_read_config,
+	.write	= versatile_write_config,
+};
+
+static struct resource io_mem = {
+	.name	= "PCI I/O space",
+	.start	= VERSATILE_PCI_MEM_BASE0,
+	.end	= VERSATILE_PCI_MEM_BASE0+VERSATILE_PCI_MEM_BASE0_SIZE-1,
+	.flags	= IORESOURCE_IO,
+};
+
+static struct resource non_mem = {
+	.name	= "PCI non-prefetchable",
+	.start	= VERSATILE_PCI_MEM_BASE1,
+	.end	= VERSATILE_PCI_MEM_BASE1+VERSATILE_PCI_MEM_BASE1_SIZE-1,
+	.flags	= IORESOURCE_MEM,
+};
+
+static struct resource pre_mem = {
+	.name	= "PCI prefetchable",
+	.start	= VERSATILE_PCI_MEM_BASE2,
+	.end	= VERSATILE_PCI_MEM_BASE2+VERSATILE_PCI_MEM_BASE2_SIZE-1,
+	.flags	= IORESOURCE_MEM | IORESOURCE_PREFETCH,
+};
+
+static int __init pci_versatile_setup_resources(struct resource **resource)
+{
+	int ret = 0;
+
+	ret = request_resource(&iomem_resource, &io_mem);
+	if (ret) {
+		printk(KERN_ERR "PCI: unable to allocate I/O "
+		       "memory region (%d)\n", ret);
+		goto out;
+	}
+	ret = request_resource(&iomem_resource, &non_mem);
+	if (ret) {
+		printk(KERN_ERR "PCI: unable to allocate non-prefetchable "
+		       "memory region (%d)\n", ret);
+		goto release_io_mem;
+	}
+	ret = request_resource(&iomem_resource, &pre_mem);
+	if (ret) {
+		printk(KERN_ERR "PCI: unable to allocate prefetchable "
+		       "memory region (%d)\n", ret);
+		goto release_non_mem;
+	}
+
+	/*
+	 * bus->resource[0] is the IO resource for this bus
+	 * bus->resource[1] is the mem resource for this bus
+	 * bus->resource[2] is the prefetch mem resource for this bus
+	 */
+	resource[0] = &io_mem;
+	resource[1] = &non_mem;
+	resource[2] = &pre_mem;
+
+	goto out;
+
+ release_non_mem:
+	release_resource(&non_mem);
+ release_io_mem:
+	release_resource(&io_mem);
+ out:
+	return ret;
+}
+
+int __init pci_versatile_setup(int nr, struct pci_sys_data *sys)
+{
+	int ret = 0;
+        int i;
+        int myslot = -1;
+	unsigned long val;
+
+	if (nr == 0) {
+		sys->mem_offset = 0;
+		ret = pci_versatile_setup_resources(sys->resource);
+		if (ret < 0) {
+			printk("pci_versatile_setup: resources... oops?\n");
+			goto out;
+		}
+	} else {
+		printk("pci_versatile_setup: resources... nr == 0??\n");
+		goto out;
+	}
+
+	__raw_writel(VERSATILE_PCI_MEM_BASE0 >> 28,PCI_IMAP0);
+	__raw_writel(VERSATILE_PCI_MEM_BASE1 >> 28,PCI_IMAP1);
+	__raw_writel(VERSATILE_PCI_MEM_BASE2 >> 28,PCI_IMAP2);
+
+	__raw_writel(1, SYS_PCICTL);
+
+	val = __raw_readl(SYS_PCICTL);
+	if (!(val & 1)) {
+		printk("Not plugged into PCI backplane!\n");
+		ret = -EIO;
+		goto out;
+	}
+
+	/*
+	 *  We need to discover the PCI core first to configure itself
+	 *  before the main PCI probing is performed
+	 */
+	for (i=0; i<32; i++) {
+		if ((__raw_readl(VERSATILE_PCI_VIRT_BASE+(i<<11)+DEVICE_ID_OFFSET) == VP_PCI_DEVICE_ID) &&
+		    (__raw_readl(VERSATILE_PCI_VIRT_BASE+(i<<11)+CLASS_ID_OFFSET) == VP_PCI_CLASS_ID)) {
+			myslot = i;
+
+			__raw_writel(myslot, PCI_SELFID);
+			val = __raw_readl(VERSATILE_PCI_CFG_VIRT_BASE+(myslot<<11)+CSR_OFFSET);
+			val |= (1<<2);
+			__raw_writel(val, VERSATILE_PCI_CFG_VIRT_BASE+(myslot<<11)+CSR_OFFSET);
+			break;
+		}
+	}
+
+	if (myslot == -1) {
+		printk("Cannot find PCI core!\n");
+		ret = -EIO;
+	} else {
+		printk("PCI core found (slot %d)\n",myslot);
+		/* Do not to map Versatile FPGA PCI device
+		   into memory space as we are short of
+		   mappable memory */
+		pci_slot_ignore |= (1 << myslot);
+		ret = 1;
+	}
+
+ out:
+	return ret;
+}
+
+
+struct pci_bus *pci_versatile_scan_bus(int nr, struct pci_sys_data *sys)
+{
+	return pci_scan_bus(sys->busnr, &pci_versatile_ops, sys);
+}
+
+/*
+ * V3_LB_BASE? - local bus address
+ * V3_LB_MAP?  - pci bus address
+ */
+void __init pci_versatile_preinit(void)
+{
+}
+
+void __init pci_versatile_postinit(void)
+{
+}
+
+
+/*
+ * map the specified device/slot/pin to an IRQ.   Different backplanes may need to modify this.
+ */
+static int __init versatile_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
+{
+	int irq;
+	int devslot = PCI_SLOT(dev->devfn);
+
+	/* slot,  pin,  irq
+	    24	  1	27
+	    25    1	28	untested
+	    26	  1	29
+	    27    1	30	untested
+	*/
+
+	irq = 27 + ((slot + pin + 2) % 3);	/* Fudged */
+
+	printk("map irq: slot %d, pin %d, devslot %d, irq: %d\n",slot,pin,devslot,irq);
+
+	return irq;
+}
+
+static struct hw_pci versatile_pci __initdata = {
+	.swizzle		= NULL,
+	.map_irq		= versatile_map_irq,
+	.nr_controllers		= 1,
+	.setup			= pci_versatile_setup,
+	.scan			= pci_versatile_scan_bus,
+	.preinit		= pci_versatile_preinit,
+	.postinit		= pci_versatile_postinit,
+};
+
+static int __init versatile_pci_init(void)
+{
+	pci_common_init(&versatile_pci);
+	return 0;
+}
+
+subsys_initcall(versatile_pci_init);