[PATCH] xtensa: Architecture support for Tensilica Xtensa Part 3

The attached patches provides part 3 of an architecture implementation for the
Tensilica Xtensa CPU series.

Signed-off-by: Chris Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 563 insertions, 0 deletions

diff --git a/arch/xtensa/kernel/pci.c b/arch/xtensa/kernel/pci.c
new file mode 100644
index 0000000..d29a816
--- /dev/null
+++ b/arch/xtensa/kernel/pci.c
@@ -0,0 +1,563 @@
+/*
+ * arch/xtensa/pcibios.c
+ *
+ * PCI bios-type initialisation for PCI machines
+ *
+ * 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.
+ *
+ * Copyright (C) 2001-2005 Tensilica Inc.
+ *
+ * Based largely on work from Cort (ppc/kernel/pci.c)
+ * IO functions copied from sparc.
+ *
+ * Chris Zankel <chris@zankel.net>
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/delay.h>
+#include <linux/string.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/errno.h>
+#include <linux/bootmem.h>
+
+#include <asm/pci-bridge.h>
+#include <asm/platform.h>
+
+#undef DEBUG
+
+#ifdef DEBUG
+#define DBG(x...) printk(x)
+#else
+#define DBG(x...)
+#endif
+
+/* PCI Controller */
+
+
+/*
+ * pcibios_alloc_controller
+ * pcibios_enable_device
+ * pcibios_fixups
+ * pcibios_align_resource
+ * pcibios_fixup_bus
+ * pcibios_setup
+ * pci_bus_add_device
+ * pci_mmap_page_range
+ */
+
+struct pci_controller* pci_ctrl_head;
+struct pci_controller** pci_ctrl_tail = &pci_ctrl_head;
+
+static int pci_bus_count;
+
+static void pcibios_fixup_resources(struct pci_dev* dev);
+
+#if 0 // FIXME
+struct pci_fixup pcibios_fixups[] = {
+	{ DECLARE_PCI_FIXUP_HEADER, PCI_ANY_ID, PCI_ANY_ID, pcibios_fixup_resources },
+	{ 0 }
+};
+#endif
+
+void
+pcibios_update_resource(struct pci_dev *dev, struct resource *root,
+			struct resource *res, int resource)
+{
+	u32 new, check, mask;
+	int reg;
+	struct pci_controller* pci_ctrl = dev->sysdata;
+
+	new = res->start;
+	if (pci_ctrl && res->flags & IORESOURCE_IO) {
+		new -= pci_ctrl->io_space.base;
+	}
+	new |= (res->flags & PCI_REGION_FLAG_MASK);
+	if (resource < 6) {
+		reg = PCI_BASE_ADDRESS_0 + 4*resource;
+	} else if (resource == PCI_ROM_RESOURCE) {
+		res->flags |= PCI_ROM_ADDRESS_ENABLE;
+		reg = dev->rom_base_reg;
+	} else {
+	/* Somebody might have asked allocation of a non-standard resource */
+		return;
+	}
+
+	pci_write_config_dword(dev, reg, new);
+	pci_read_config_dword(dev, reg, &check);
+	mask = (new & PCI_BASE_ADDRESS_SPACE_IO) ?
+		PCI_BASE_ADDRESS_IO_MASK : PCI_BASE_ADDRESS_MEM_MASK;
+
+	if ((new ^ check) & mask) {
+		printk(KERN_ERR "PCI: Error while updating region "
+		       "%s/%d (%08x != %08x)\n", dev->slot_name, resource,
+		       new, check);
+	}
+}
+
+/*
+ * 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 have be mirrored at 0x0100-0x03ff..
+ */
+void
+pcibios_align_resource(void *data, struct resource *res, unsigned long size,
+    		       unsigned long align)
+{
+	struct pci_dev *dev = data;
+
+	if (res->flags & IORESOURCE_IO) {
+		unsigned long start = res->start;
+
+		if (size > 0x100) {
+			printk(KERN_ERR "PCI: I/O Region %s/%d too large"
+			       " (%ld bytes)\n", dev->slot_name,
+			       dev->resource - res, size);
+		}
+
+		if (start & 0x300) {
+			start = (start + 0x3ff) & ~0x3ff;
+			res->start = start;
+		}
+	}
+}
+
+int
+pcibios_enable_resources(struct pci_dev *dev, int mask)
+{
+	u16 cmd, old_cmd;
+	int idx;
+	struct resource *r;
+
+	pci_read_config_word(dev, PCI_COMMAND, &cmd);
+	old_cmd = cmd;
+	for(idx=0; idx<6; idx++) {
+		r = &dev->resource[idx];
+		if (!r->start && r->end) {
+			printk (KERN_ERR "PCI: Device %s not available because "
+				"of resource collisions\n", dev->slot_name);
+			return -EINVAL;
+		}
+		if (r->flags & IORESOURCE_IO)
+			cmd |= PCI_COMMAND_IO;
+		if (r->flags & IORESOURCE_MEM)
+			cmd |= PCI_COMMAND_MEMORY;
+	}
+	if (dev->resource[PCI_ROM_RESOURCE].start)
+		cmd |= PCI_COMMAND_MEMORY;
+	if (cmd != old_cmd) {
+		printk("PCI: Enabling device %s (%04x -> %04x)\n",
+			dev->slot_name, old_cmd, cmd);
+		pci_write_config_word(dev, PCI_COMMAND, cmd);
+	}
+	return 0;
+}
+
+struct pci_controller * __init pcibios_alloc_controller(void)
+{
+	struct pci_controller *pci_ctrl;
+
+	pci_ctrl = (struct pci_controller *)alloc_bootmem(sizeof(*pci_ctrl));
+	memset(pci_ctrl, 0, sizeof(struct pci_controller));
+
+	*pci_ctrl_tail = pci_ctrl;
+	pci_ctrl_tail = &pci_ctrl->next;
+
+	return pci_ctrl;
+}
+
+static int __init pcibios_init(void)
+{
+	struct pci_controller *pci_ctrl;
+	struct pci_bus *bus;
+	int next_busno = 0, i;
+
+	printk("PCI: Probing PCI hardware\n");
+
+	/* Scan all of the recorded PCI controllers.  */
+	for (pci_ctrl = pci_ctrl_head; pci_ctrl; pci_ctrl = pci_ctrl->next) {
+		pci_ctrl->last_busno = 0xff;
+		bus = pci_scan_bus(pci_ctrl->first_busno, pci_ctrl->ops,
+				   pci_ctrl);
+		if (pci_ctrl->io_resource.flags) {
+			unsigned long offs;
+
+			offs = (unsigned long)pci_ctrl->io_space.base;
+			pci_ctrl->io_resource.start += offs;
+			pci_ctrl->io_resource.end += offs;
+			bus->resource[0] = &pci_ctrl->io_resource;
+		}
+		for (i = 0; i < 3; ++i)
+			if (pci_ctrl->mem_resources[i].flags)
+				bus->resource[i+1] =&pci_ctrl->mem_resources[i];
+		pci_ctrl->bus = bus;
+		pci_ctrl->last_busno = bus->subordinate;
+		if (next_busno <= pci_ctrl->last_busno)
+			next_busno = pci_ctrl->last_busno+1;
+	}
+	pci_bus_count = next_busno;
+
+	return platform_pcibios_fixup();
+}
+
+subsys_initcall(pcibios_init);
+
+void __init pcibios_fixup_bus(struct pci_bus *bus)
+{
+	struct pci_controller *pci_ctrl = bus->sysdata;
+	struct resource *res;
+	unsigned long io_offset;
+	int i;
+
+	io_offset = (unsigned long)pci_ctrl->io_space.base;
+	if (bus->parent == NULL) {
+		/* this is a host bridge - fill in its resources */
+		pci_ctrl->bus = bus;
+
+		bus->resource[0] = res = &pci_ctrl->io_resource;
+		if (!res->flags) {
+			if (io_offset)
+				printk (KERN_ERR "I/O resource not set for host"
+					" bridge %d\n", pci_ctrl->index);
+			res->start = 0;
+			res->end = IO_SPACE_LIMIT;
+			res->flags = IORESOURCE_IO;
+		}
+		res->start += io_offset;
+		res->end += io_offset;
+
+		for (i = 0; i < 3; i++) {
+			res = &pci_ctrl->mem_resources[i];
+			if (!res->flags) {
+				if (i > 0)
+					continue;
+				printk(KERN_ERR "Memory resource not set for "
+				       "host bridge %d\n", pci_ctrl->index);
+				res->start = 0;
+				res->end = ~0U;
+				res->flags = IORESOURCE_MEM;
+			}
+			bus->resource[i+1] = res;
+		}
+	} else {
+		/* This is a subordinate bridge */
+		pci_read_bridge_bases(bus);
+
+		for (i = 0; i < 4; i++) {
+			if ((res = bus->resource[i]) == NULL || !res->flags)
+				continue;
+			if (io_offset && (res->flags & IORESOURCE_IO)) {
+				res->start += io_offset;
+				res->end += io_offset;
+			}
+		}
+	}
+}
+
+char __init *pcibios_setup(char *str)
+{
+	return str;
+}
+
+/* the next one is stolen from the alpha port... */
+
+void __init
+pcibios_update_irq(struct pci_dev *dev, int irq)
+{
+	pci_write_config_byte(dev, PCI_INTERRUPT_LINE, irq);
+}
+
+int pcibios_enable_device(struct pci_dev *dev, int mask)
+{
+	u16 cmd, old_cmd;
+	int idx;
+	struct resource *r;
+
+	pci_read_config_word(dev, PCI_COMMAND, &cmd);
+	old_cmd = cmd;
+	for (idx=0; idx<6; idx++) {
+		r = &dev->resource[idx];
+		if (!r->start && r->end) {
+			printk(KERN_ERR "PCI: Device %s not available because "
+			       "of resource collisions\n", dev->slot_name);
+			return -EINVAL;
+		}
+		if (r->flags & IORESOURCE_IO)
+			cmd |= PCI_COMMAND_IO;
+		if (r->flags & IORESOURCE_MEM)
+			cmd |= PCI_COMMAND_MEMORY;
+	}
+	if (cmd != old_cmd) {
+		printk("PCI: Enabling device %s (%04x -> %04x)\n",
+		       dev->slot_name, old_cmd, cmd);
+		pci_write_config_word(dev, PCI_COMMAND, cmd);
+	}
+
+	return 0;
+}
+
+#ifdef CONFIG_PROC_FS
+
+/*
+ * Return the index of the PCI controller for device pdev.
+ */
+
+int
+pci_controller_num(struct pci_dev *dev)
+{
+	struct pci_controller *pci_ctrl = (struct pci_controller*) dev->sysdata;
+	return pci_ctrl->index;
+}
+
+#endif /* CONFIG_PROC_FS */
+
+
+static void
+pcibios_fixup_resources(struct pci_dev *dev)
+{
+	struct pci_controller* pci_ctrl = (struct pci_controller *)dev->sysdata;
+	int i;
+	unsigned long offset;
+
+	if (!pci_ctrl) {
+		printk(KERN_ERR "No pci_ctrl for PCI dev %s!\n",dev->slot_name);
+		return;
+	}
+	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
+		struct resource *res = dev->resource + i;
+		if (!res->start || !res->flags)
+			continue;
+		if (res->end == 0xffffffff) {
+			DBG("PCI:%s Resource %d [%08lx-%08lx] is unassigned\n",
+			    dev->slot_name, i, res->start, res->end);
+			res->end -= res->start;
+			res->start = 0;
+			continue;
+		}
+		offset = 0;
+		if (res->flags & IORESOURCE_IO)
+			offset = (unsigned long) pci_ctrl->io_space.base;
+		else if (res->flags & IORESOURCE_MEM)
+			offset = (unsigned long) pci_ctrl->mem_space.base;
+
+		if (offset != 0) {
+			res->start += offset;
+			res->end += offset;
+#ifdef DEBUG
+			printk("Fixup res %d (%lx) of dev %s: %lx -> %lx\n",
+			       i, res->flags, dev->slot_name,
+			       res->start - offset, res->start);
+#endif
+		}
+	}
+}
+
+/*
+ * Platform support for /proc/bus/pci/X/Y mmap()s,
+ * modelled on the sparc64 implementation by Dave Miller.
+ *  -- paulus.
+ */
+
+/*
+ * Adjust vm_pgoff of VMA such that it is the physical page offset
+ * corresponding to the 32-bit pci bus offset for DEV requested by the user.
+ *
+ * Basically, the user finds the base address for his device which he wishes
+ * to mmap.  They read the 32-bit value from the config space base register,
+ * add whatever PAGE_SIZE multiple offset they wish, and feed this into the
+ * offset parameter of mmap on /proc/bus/pci/XXX for that device.
+ *
+ * Returns negative error code on failure, zero on success.
+ */
+static __inline__ int
+__pci_mmap_make_offset(struct pci_dev *dev, struct vm_area_struct *vma,
+		       enum pci_mmap_state mmap_state)
+{
+	struct pci_controller *pci_ctrl = (struct pci_controller*) dev->sysdata;
+	unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
+	unsigned long io_offset = 0;
+	int i, res_bit;
+
+	if (pci_ctrl == 0)
+		return -EINVAL;		/* should never happen */
+
+	/* If memory, add on the PCI bridge address offset */
+	if (mmap_state == pci_mmap_mem) {
+		res_bit = IORESOURCE_MEM;
+	} else {
+		io_offset = (unsigned long)pci_ctrl->io_space.base;
+		offset += io_offset;
+		res_bit = IORESOURCE_IO;
+	}
+
+	/*
+	 * Check that the offset requested corresponds to one of the
+	 * resources of the device.
+	 */
+	for (i = 0; i <= PCI_ROM_RESOURCE; i++) {
+		struct resource *rp = &dev->resource[i];
+		int flags = rp->flags;
+
+		/* treat ROM as memory (should be already) */
+		if (i == PCI_ROM_RESOURCE)
+			flags |= IORESOURCE_MEM;
+
+		/* Active and same type? */
+		if ((flags & res_bit) == 0)
+			continue;
+
+		/* In the range of this resource? */
+		if (offset < (rp->start & PAGE_MASK) || offset > rp->end)
+			continue;
+
+		/* found it! construct the final physical address */
+		if (mmap_state == pci_mmap_io)
+			offset += pci_ctrl->io_space.start - io_offset;
+		vma->vm_pgoff = offset >> PAGE_SHIFT;
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+/*
+ * Set vm_flags of VMA, as appropriate for this architecture, for a pci device
+ * mapping.
+ */
+static __inline__ void
+__pci_mmap_set_flags(struct pci_dev *dev, struct vm_area_struct *vma,
+		     enum pci_mmap_state mmap_state)
+{
+	vma->vm_flags |= VM_SHM | VM_LOCKED | VM_IO;
+}
+
+/*
+ * Set vm_page_prot of VMA, as appropriate for this architecture, for a pci
+ * device mapping.
+ */
+static __inline__ void
+__pci_mmap_set_pgprot(struct pci_dev *dev, struct vm_area_struct *vma,
+		      enum pci_mmap_state mmap_state, int write_combine)
+{
+	int prot = pgprot_val(vma->vm_page_prot);
+
+	/* Set to write-through */
+	prot &= ~_PAGE_NO_CACHE;
+#if 0
+	if (!write_combine)
+		prot |= _PAGE_WRITETHRU;
+#endif
+	vma->vm_page_prot = __pgprot(prot);
+}
+
+/*
+ * Perform the actual remap of the pages for a PCI device mapping, as
+ * appropriate for this architecture.  The region in the process to map
+ * is described by vm_start and vm_end members of VMA, the base physical
+ * address is found in vm_pgoff.
+ * The pci device structure is provided so that architectures may make mapping
+ * decisions on a per-device or per-bus basis.
+ *
+ * Returns a negative error code on failure, zero on success.
+ */
+int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
+			enum pci_mmap_state mmap_state,
+			int write_combine)
+{
+	int ret;
+
+	ret = __pci_mmap_make_offset(dev, vma, mmap_state);
+	if (ret < 0)
+		return ret;
+
+	__pci_mmap_set_flags(dev, vma, mmap_state);
+	__pci_mmap_set_pgprot(dev, vma, mmap_state, write_combine);
+
+	ret = io_remap_page_range(vma, vma->vm_start, vma->vm_pgoff<<PAGE_SHIFT,
+			       vma->vm_end - vma->vm_start, vma->vm_page_prot);
+
+	return ret;
+}
+
+/*
+ * 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 horroble macroses 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;
+                writeb(*(const char *)src, addr);
+                src += 1;
+                addr += 1;
+        }
+}
+
+void outsw(unsigned long addr, const void *src, unsigned long count) {
+        while (count) {
+                count -= 2;
+                writew(*(const short *)src, addr);
+                src += 2;
+                addr += 2;
+        }
+}
+
+void outsl(unsigned long addr, const void *src, unsigned long count) {
+        while (count) {
+                count -= 4;
+                writel(*(const long *)src, addr);
+                src += 4;
+                addr += 4;
+        }
+}
+
+void insb(unsigned long addr, void *dst, unsigned long count) {
+        while (count) {
+                count -= 1;
+                *(unsigned char *)dst = readb(addr);
+                dst += 1;
+                addr += 1;
+        }
+}
+
+void insw(unsigned long addr, void *dst, unsigned long count) {
+        while (count) {
+                count -= 2;
+                *(unsigned short *)dst = readw(addr);
+                dst += 2;
+                addr += 2;
+        }
+}
+
+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 = readl(addr);
+                dst += 4;
+                addr += 4;
+        }
+}
+
+
+