OMAP: iommu: add initial debugfs support
This enables to peek the following data.
$ /debug/iommu/isp# ls
mem nr_tlb_entries regs
mmap pagetable tlb
$ /debug/iommu/isp# head pagetable
L: da: pa:
-----------------------------------------
2: 00001000 8ae4a002
2: 00002000 8e7bb002
2: 00003000 8ae49002
2: 00004000 8ae65002
.....
Signed-off-by: Hiroshi DOYU <Hiroshi.DOYU@nokia.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
diff --git a/arch/arm/plat-omap/iommu-debug.c b/arch/arm/plat-omap/iommu-debug.c
new file mode 100644
index 0000000..c799b3b
--- /dev/null
+++ b/arch/arm/plat-omap/iommu-debug.c
@@ -0,0 +1,415 @@
+/*
+ * omap iommu: debugfs interface
+ *
+ * Copyright (C) 2008-2009 Nokia Corporation
+ *
+ * Written by Hiroshi DOYU <Hiroshi.DOYU@nokia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/uaccess.h>
+#include <linux/platform_device.h>
+#include <linux/debugfs.h>
+
+#include <mach/iommu.h>
+#include <mach/iovmm.h>
+
+#include "iopgtable.h"
+
+#define MAXCOLUMN 100 /* for short messages */
+
+static DEFINE_MUTEX(iommu_debug_lock);
+
+static struct dentry *iommu_debug_root;
+
+static ssize_t debug_read_ver(struct file *file, char __user *userbuf,
+ size_t count, loff_t *ppos)
+{
+ u32 ver = iommu_arch_version();
+ char buf[MAXCOLUMN], *p = buf;
+
+ p += sprintf(p, "H/W version: %d.%d\n", (ver >> 4) & 0xf , ver & 0xf);
+
+ return simple_read_from_buffer(userbuf, count, ppos, buf, p - buf);
+}
+
+static ssize_t debug_read_regs(struct file *file, char __user *userbuf,
+ size_t count, loff_t *ppos)
+{
+ struct iommu *obj = file->private_data;
+ char *p, *buf;
+ ssize_t bytes;
+
+ buf = kmalloc(count, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+ p = buf;
+
+ mutex_lock(&iommu_debug_lock);
+
+ bytes = iommu_dump_ctx(obj, p, count);
+ bytes = simple_read_from_buffer(userbuf, count, ppos, buf, bytes);
+
+ mutex_unlock(&iommu_debug_lock);
+ kfree(buf);
+
+ return bytes;
+}
+
+static ssize_t debug_read_tlb(struct file *file, char __user *userbuf,
+ size_t count, loff_t *ppos)
+{
+ struct iommu *obj = file->private_data;
+ char *p, *buf;
+ ssize_t bytes, rest;
+
+ buf = kmalloc(count, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+ p = buf;
+
+ mutex_lock(&iommu_debug_lock);
+
+ p += sprintf(p, "%8s %8s\n", "cam:", "ram:");
+ p += sprintf(p, "-----------------------------------------\n");
+ rest = count - (p - buf);
+ p += dump_tlb_entries(obj, p, rest);
+
+ bytes = simple_read_from_buffer(userbuf, count, ppos, buf, p - buf);
+
+ mutex_unlock(&iommu_debug_lock);
+ kfree(buf);
+
+ return bytes;
+}
+
+static ssize_t debug_write_pagetable(struct file *file,
+ const char __user *userbuf, size_t count, loff_t *ppos)
+{
+ struct iotlb_entry e;
+ struct cr_regs cr;
+ int err;
+ struct iommu *obj = file->private_data;
+ char buf[MAXCOLUMN], *p = buf;
+
+ count = min(count, sizeof(buf));
+
+ mutex_lock(&iommu_debug_lock);
+ if (copy_from_user(p, userbuf, count)) {
+ mutex_unlock(&iommu_debug_lock);
+ return -EFAULT;
+ }
+
+ sscanf(p, "%x %x", &cr.cam, &cr.ram);
+ if (!cr.cam || !cr.ram) {
+ mutex_unlock(&iommu_debug_lock);
+ return -EINVAL;
+ }
+
+ iotlb_cr_to_e(&cr, &e);
+ err = iopgtable_store_entry(obj, &e);
+ if (err)
+ dev_err(obj->dev, "%s: fail to store cr\n", __func__);
+
+ mutex_unlock(&iommu_debug_lock);
+ return count;
+}
+
+#define dump_ioptable_entry_one(lv, da, val) \
+ ({ \
+ int __err = 0; \
+ ssize_t bytes; \
+ const int maxcol = 22; \
+ const char *str = "%d: %08x %08x\n"; \
+ bytes = snprintf(p, maxcol, str, lv, da, val); \
+ p += bytes; \
+ len -= bytes; \
+ if (len < maxcol) \
+ __err = -ENOMEM; \
+ __err; \
+ })
+
+static ssize_t dump_ioptable(struct iommu *obj, char *buf, ssize_t len)
+{
+ int i;
+ u32 *iopgd;
+ char *p = buf;
+
+ spin_lock(&obj->page_table_lock);
+
+ iopgd = iopgd_offset(obj, 0);
+ for (i = 0; i < PTRS_PER_IOPGD; i++, iopgd++) {
+ int j, err;
+ u32 *iopte;
+ u32 da;
+
+ if (!*iopgd)
+ continue;
+
+ if (!(*iopgd & IOPGD_TABLE)) {
+ da = i << IOPGD_SHIFT;
+
+ err = dump_ioptable_entry_one(1, da, *iopgd);
+ if (err)
+ goto out;
+ continue;
+ }
+
+ iopte = iopte_offset(iopgd, 0);
+
+ for (j = 0; j < PTRS_PER_IOPTE; j++, iopte++) {
+ if (!*iopte)
+ continue;
+
+ da = (i << IOPGD_SHIFT) + (j << IOPTE_SHIFT);
+ err = dump_ioptable_entry_one(2, da, *iopgd);
+ if (err)
+ goto out;
+ }
+ }
+out:
+ spin_unlock(&obj->page_table_lock);
+
+ return p - buf;
+}
+
+static ssize_t debug_read_pagetable(struct file *file, char __user *userbuf,
+ size_t count, loff_t *ppos)
+{
+ struct iommu *obj = file->private_data;
+ char *p, *buf;
+ size_t bytes;
+
+ buf = (char *)__get_free_page(GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+ p = buf;
+
+ p += sprintf(p, "L: %8s %8s\n", "da:", "pa:");
+ p += sprintf(p, "-----------------------------------------\n");
+
+ mutex_lock(&iommu_debug_lock);
+
+ bytes = PAGE_SIZE - (p - buf);
+ p += dump_ioptable(obj, p, bytes);
+
+ bytes = simple_read_from_buffer(userbuf, count, ppos, buf, p - buf);
+
+ mutex_unlock(&iommu_debug_lock);
+ free_page((unsigned long)buf);
+
+ return bytes;
+}
+
+static ssize_t debug_read_mmap(struct file *file, char __user *userbuf,
+ size_t count, loff_t *ppos)
+{
+ struct iommu *obj = file->private_data;
+ char *p, *buf;
+ struct iovm_struct *tmp;
+ int uninitialized_var(i);
+ ssize_t bytes;
+
+ buf = (char *)__get_free_page(GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+ p = buf;
+
+ p += sprintf(p, "%-3s %-8s %-8s %6s %8s\n",
+ "No", "start", "end", "size", "flags");
+ p += sprintf(p, "-------------------------------------------------\n");
+
+ mutex_lock(&iommu_debug_lock);
+
+ list_for_each_entry(tmp, &obj->mmap, list) {
+ size_t len;
+ const char *str = "%3d %08x-%08x %6x %8x\n";
+ const int maxcol = 39;
+
+ len = tmp->da_end - tmp->da_start;
+ p += snprintf(p, maxcol, str,
+ i, tmp->da_start, tmp->da_end, len, tmp->flags);
+
+ if (PAGE_SIZE - (p - buf) < maxcol)
+ break;
+ i++;
+ }
+
+ bytes = simple_read_from_buffer(userbuf, count, ppos, buf, p - buf);
+
+ mutex_unlock(&iommu_debug_lock);
+ free_page((unsigned long)buf);
+
+ return bytes;
+}
+
+static ssize_t debug_read_mem(struct file *file, char __user *userbuf,
+ size_t count, loff_t *ppos)
+{
+ struct iommu *obj = file->private_data;
+ char *p, *buf;
+ struct iovm_struct *area;
+ ssize_t bytes;
+
+ count = min_t(ssize_t, count, PAGE_SIZE);
+
+ buf = (char *)__get_free_page(GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+ p = buf;
+
+ mutex_lock(&iommu_debug_lock);
+
+ area = find_iovm_area(obj, (u32)ppos);
+ if (IS_ERR(area)) {
+ bytes = -EINVAL;
+ goto err_out;
+ }
+ memcpy(p, area->va, count);
+ p += count;
+
+ bytes = simple_read_from_buffer(userbuf, count, ppos, buf, p - buf);
+err_out:
+ mutex_unlock(&iommu_debug_lock);
+ free_page((unsigned long)buf);
+
+ return bytes;
+}
+
+static ssize_t debug_write_mem(struct file *file, const char __user *userbuf,
+ size_t count, loff_t *ppos)
+{
+ struct iommu *obj = file->private_data;
+ struct iovm_struct *area;
+ char *p, *buf;
+
+ count = min_t(size_t, count, PAGE_SIZE);
+
+ buf = (char *)__get_free_page(GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+ p = buf;
+
+ mutex_lock(&iommu_debug_lock);
+
+ if (copy_from_user(p, userbuf, count)) {
+ count = -EFAULT;
+ goto err_out;
+ }
+
+ area = find_iovm_area(obj, (u32)ppos);
+ if (IS_ERR(area)) {
+ count = -EINVAL;
+ goto err_out;
+ }
+ memcpy(area->va, p, count);
+err_out:
+ mutex_unlock(&iommu_debug_lock);
+ free_page((unsigned long)buf);
+
+ return count;
+}
+
+static int debug_open_generic(struct inode *inode, struct file *file)
+{
+ file->private_data = inode->i_private;
+ return 0;
+}
+
+#define DEBUG_FOPS(name) \
+ static const struct file_operations debug_##name##_fops = { \
+ .open = debug_open_generic, \
+ .read = debug_read_##name, \
+ .write = debug_write_##name, \
+ };
+
+#define DEBUG_FOPS_RO(name) \
+ static const struct file_operations debug_##name##_fops = { \
+ .open = debug_open_generic, \
+ .read = debug_read_##name, \
+ };
+
+DEBUG_FOPS_RO(ver);
+DEBUG_FOPS_RO(regs);
+DEBUG_FOPS_RO(tlb);
+DEBUG_FOPS(pagetable);
+DEBUG_FOPS_RO(mmap);
+DEBUG_FOPS(mem);
+
+#define __DEBUG_ADD_FILE(attr, mode) \
+ { \
+ struct dentry *dent; \
+ dent = debugfs_create_file(#attr, mode, parent, \
+ obj, &debug_##attr##_fops); \
+ if (!dent) \
+ return -ENOMEM; \
+ }
+
+#define DEBUG_ADD_FILE(name) __DEBUG_ADD_FILE(name, 600)
+#define DEBUG_ADD_FILE_RO(name) __DEBUG_ADD_FILE(name, 400)
+
+static int iommu_debug_register(struct device *dev, void *data)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct iommu *obj = platform_get_drvdata(pdev);
+ struct dentry *d, *parent;
+
+ if (!obj || !obj->dev)
+ return -EINVAL;
+
+ d = debugfs_create_dir(obj->name, iommu_debug_root);
+ if (!d)
+ return -ENOMEM;
+ parent = d;
+
+ d = debugfs_create_u8("nr_tlb_entries", 400, parent,
+ (u8 *)&obj->nr_tlb_entries);
+ if (!d)
+ return -ENOMEM;
+
+ DEBUG_ADD_FILE_RO(ver);
+ DEBUG_ADD_FILE_RO(regs);
+ DEBUG_ADD_FILE_RO(tlb);
+ DEBUG_ADD_FILE(pagetable);
+ DEBUG_ADD_FILE_RO(mmap);
+ DEBUG_ADD_FILE(mem);
+
+ return 0;
+}
+
+static int __init iommu_debug_init(void)
+{
+ struct dentry *d;
+ int err;
+
+ d = debugfs_create_dir("iommu", NULL);
+ if (!d)
+ return -ENOMEM;
+ iommu_debug_root = d;
+
+ err = foreach_iommu_device(d, iommu_debug_register);
+ if (err)
+ goto err_out;
+ return 0;
+
+err_out:
+ debugfs_remove_recursive(iommu_debug_root);
+ return err;
+}
+module_init(iommu_debug_init)
+
+static void __exit iommu_debugfs_exit(void)
+{
+ debugfs_remove_recursive(iommu_debug_root);
+}
+module_exit(iommu_debugfs_exit)
+
+MODULE_DESCRIPTION("omap iommu: debugfs interface");
+MODULE_AUTHOR("Hiroshi DOYU <Hiroshi.DOYU@nokia.com>");
+MODULE_LICENSE("GPL v2");