This commit adds debugfs directory and nodes for inspecting internal
state of System MMU.
Signed-off-by: KyongHo Cho <[email protected]>
---
drivers/iommu/exynos-iommu.c | 204 +++++++++++++++++++++++++++++++++++++++++--
1 file changed, 198 insertions(+), 6 deletions(-)
diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index 128c811..8ff7e97 100644
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -26,12 +26,17 @@
#include <linux/list.h>
#include <linux/memblock.h>
#include <linux/export.h>
+#include <linux/fs.h>
+#include <linux/seq_file.h>
+#include <linux/debugfs.h>
#include <linux/string.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <asm/cacheflush.h>
+#define MODULE_NAME "exynos-sysmmu"
+
/* We does not consider super section mapping (16MB) */
#define SECT_ORDER 20
#define LPAGE_ORDER 16
@@ -237,6 +242,7 @@ struct sysmmu_drvdata {
spinlock_t lock;
struct sysmmu_prefbuf pbufs[MAX_NUM_PBUF];
int num_pbufs;
+ struct dentry *debugfs_root;
struct iommu_domain *domain;
sysmmu_fault_handler_t fault_handler;
unsigned long pgtable;
@@ -1094,6 +1100,8 @@ static void __init __sysmmu_init_mmuname(struct device *sysmmu,
}
}
+static void __create_debugfs_entry(struct sysmmu_drvdata *drvdata);
+
static int __init exynos_sysmmu_probe(struct platform_device *pdev)
{
int i, ret;
@@ -1170,6 +1178,8 @@ static int __init exynos_sysmmu_probe(struct platform_device *pdev)
__set_fault_handler(data, &default_fault_handler);
+ __create_debugfs_entry(data);
+
dev->archdata.iommu = &sysmmu_placeholder;
dev_dbg(dev, "Initialized successfully!\n");
}
@@ -1272,7 +1282,7 @@ static struct platform_driver exynos_sysmmu_driver __refdata = {
.probe = exynos_sysmmu_probe,
.driver = {
.owner = THIS_MODULE,
- .name = "exynos-sysmmu",
+ .name = MODULE_NAME,
.pm = &__pm_ops,
.of_match_table = of_match_ptr(sysmmu_of_match),
}
@@ -1649,6 +1659,8 @@ static struct iommu_ops exynos_iommu_ops = {
.pgsize_bitmap = SECT_SIZE | LPAGE_SIZE | SPAGE_SIZE,
};
+static struct dentry *sysmmu_debugfs_root; /* /sys/kernel/debug/sysmmu */
+
static int __init exynos_iommu_init(void)
{
int ret;
@@ -1660,17 +1672,197 @@ static int __init exynos_iommu_init(void)
return -ENOMEM;
}
- ret = platform_driver_register(&exynos_sysmmu_driver);
+ ret = bus_set_iommu(&platform_bus_type, &exynos_iommu_ops);
+ if (ret) {
+ kmem_cache_destroy(lv2table_kmem_cache);
+ pr_err("%s: Failed to register IOMMU ops\n", __func__);
+ return -EFAULT;
+ }
- if (ret == 0)
- ret = bus_set_iommu(&platform_bus_type, &exynos_iommu_ops);
+ sysmmu_debugfs_root = debugfs_create_dir("sysmmu", NULL);
+ if (!sysmmu_debugfs_root)
+ pr_err("%s: Failed to create debugfs entry, 'sysmmu'\n",
+ __func__);
+ if (IS_ERR(sysmmu_debugfs_root))
+ sysmmu_debugfs_root = NULL;
+ ret = platform_driver_register(&exynos_sysmmu_driver);
if (ret) {
- pr_err("%s: Failed to register exynos-iommu driver.\n",
- __func__);
kmem_cache_destroy(lv2table_kmem_cache);
+ pr_err("%s: Failed to register System MMU driver\n", __func__);
}
return ret;
}
subsys_initcall(exynos_iommu_init);
+
+static int debug_string_show(struct seq_file *s, void *unused)
+{
+ char *str = s->private;
+
+ seq_printf(s, "%s\n", str);
+
+ return 0;
+}
+
+static int debug_sysmmu_list_show(struct seq_file *s, void *unused)
+{
+ struct sysmmu_drvdata *drvdata = s->private;
+ struct platform_device *pdev = to_platform_device(drvdata->sysmmu);
+ int idx, maj, min, ret;
+
+ seq_printf(s, "SysMMU Name | Ver | SFR Base\n");
+
+ if (pm_runtime_enabled(drvdata->sysmmu)) {
+ ret = pm_runtime_get_sync(drvdata->sysmmu);
+ if (ret < 0)
+ return ret;
+ }
+
+ for (idx = 0; idx < drvdata->nsfrs; idx++) {
+ struct resource *res;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, idx);
+ if (!res)
+ break;
+
+ maj = __sysmmu_version(drvdata, idx, &min);
+
+ if (drvdata->mmuname) {
+ if (maj == 0)
+ seq_printf(s, "%11.s | N/A | 0x%08x\n",
+ drvdata->mmuname[idx], res->start);
+ else
+ seq_printf(s, "%11.s | %d.%d | 0x%08x\n",
+ drvdata->mmuname[idx], maj, min, res->start);
+ } else {
+ if (maj == 0)
+ seq_printf(s, "N/A | 0x%08x\n", res->start);
+ else
+ seq_printf(s, "%d.%d | 0x%08x\n",
+ maj, min, res->start);
+ }
+ }
+
+ if (pm_runtime_enabled(drvdata->sysmmu))
+ pm_runtime_put(drvdata->sysmmu);
+
+ return 0;
+}
+
+static int debug_next_sibling_show(struct seq_file *s, void *unused)
+{
+ struct device *dev = s->private;
+
+ if (dev->parent &&
+ !strncmp(dev_name(dev->parent),
+ MODULE_NAME, strlen(MODULE_NAME)))
+ seq_printf(s, "%s\n", dev_name(dev->parent));
+ return 0;
+}
+
+static int __show_master(struct device *dev, void *data)
+{
+ struct seq_file *s = data;
+
+ if (strncmp(dev_name(dev), MODULE_NAME, strlen(MODULE_NAME)))
+ seq_printf(s, "%s\n", dev_name(dev));
+ return 0;
+}
+
+static int debug_master_show(struct seq_file *s, void *unused)
+{
+ struct device *dev = s->private;
+
+ device_for_each_child(dev, s, __show_master);
+ return 0;
+}
+
+static int debug_string_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, debug_string_show, inode->i_private);
+}
+
+static int debug_sysmmu_list_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, debug_sysmmu_list_show, inode->i_private);
+}
+
+static int debug_next_sibling_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, debug_next_sibling_show, inode->i_private);
+}
+
+static int debug_master_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, debug_master_show, inode->i_private);
+}
+
+static const struct file_operations debug_string_fops = {
+ .open = debug_string_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static const struct file_operations debug_sysmmu_list_fops = {
+ .open = debug_sysmmu_list_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static const struct file_operations debug_next_sibling_fops = {
+ .open = debug_next_sibling_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static const struct file_operations debug_master_fops = {
+ .open = debug_master_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static void __init __create_debugfs_entry(struct sysmmu_drvdata *drvdata)
+{
+ if (!sysmmu_debugfs_root)
+ return;
+
+ drvdata->debugfs_root = debugfs_create_dir(dev_name(drvdata->sysmmu),
+ sysmmu_debugfs_root);
+ if (!drvdata->debugfs_root)
+ dev_err(drvdata->sysmmu, "Failed to create debugfs dentry\n");
+ if (IS_ERR(drvdata->debugfs_root))
+ drvdata->debugfs_root = NULL;
+
+ if (!drvdata->debugfs_root)
+ return;
+
+ if (!debugfs_create_u32("enable", 0664, drvdata->debugfs_root,
+ &drvdata->activations))
+ dev_err(drvdata->sysmmu,
+ "Failed to create debugfs file 'enable'\n");
+
+ if (!debugfs_create_x32("pagetable", 0664, drvdata->debugfs_root,
+ (u32 *)&drvdata->pgtable))
+ dev_err(drvdata->sysmmu,
+ "Failed to create debugfs file 'pagetable'\n");
+
+ if (!debugfs_create_file("sysmmu_list", 0444, drvdata->debugfs_root,
+ drvdata, &debug_sysmmu_list_fops))
+ dev_err(drvdata->sysmmu,
+ "Failed to create debugfs file 'sysmmu_list'\n");
+
+ if (!debugfs_create_file("next_sibling", 0x444, drvdata->debugfs_root,
+ drvdata->sysmmu, &debug_next_sibling_fops))
+ dev_err(drvdata->sysmmu,
+ "Failed to create debugfs file 'next_siblings'\n");
+
+ if (!debugfs_create_file("master", 0x444, drvdata->debugfs_root,
+ drvdata->sysmmu, &debug_master_fops))
+ dev_err(drvdata->sysmmu,
+ "Failed to create debugfs file 'next_siblings'\n");
+}
--
1.8.0