gpu: pvr: add debugfs entry to read the EDM trace

Signed-off-by: Imre Deak <imre.deak@nokia.com>

diff --git a/pvr/pvr_debug.c b/pvr/pvr_debug.c
index 0f49175..1c89499 100644 (file)
--- a/pvr/pvr_debug.c
+++ b/pvr/pvr_debug.c
@@ -32,6 +32,8 @@
 #include <linux/spinlock.h>
 #include <linux/tty.h>
 #include <linux/debugfs.h>
+#include <linux/vmalloc.h>
+
 #include <stdarg.h>
 #include "img_types.h"
 #include "servicesext.h"
@@ -325,6 +327,54 @@ static int pvr_dbg_set(void *data, u64 val)
 
 DEFINE_SIMPLE_ATTRIBUTE(pvr_dbg_fops, NULL, pvr_dbg_set, "%llu\n");
 
+struct edm_buf_info {
+       size_t len;
+       char data[1];
+};
+
+static int pvr_dbg_edm_open(struct inode *inode, struct file *file)
+{
+       struct PVRSRV_DEVICE_NODE *node;
+       struct PVRSRV_SGXDEV_INFO *sgx_info;
+       struct edm_buf_info *bi;
+       size_t size;
+
+       /* Take a snapshot of the EDM trace buffer */
+       size = SGXMK_TRACE_BUFFER_SIZE * SGXMK_TRACE_BUF_STR_LEN;
+       bi = vmalloc(sizeof(*bi) + size);
+       if (!bi)
+               return -ENOMEM;
+
+       node = get_sgx_node();
+       sgx_info = node->pvDevice;
+       bi->len = snprint_edm_trace(sgx_info, bi->data, size);
+       file->private_data = bi;
+
+       return 0;
+}
+
+static int pvr_dbg_edm_release(struct inode *inode, struct file *file)
+{
+       vfree(file->private_data);
+
+       return 0;
+}
+
+static ssize_t pvr_dbg_edm_read(struct file *file, char __user *buffer,
+                               size_t count, loff_t *ppos)
+{
+       struct edm_buf_info *bi = file->private_data;
+
+       return simple_read_from_buffer(buffer, count, ppos, bi->data, bi->len);
+}
+
+static const struct file_operations pvr_dbg_edm_fops = {
+       .owner          = THIS_MODULE,
+       .open           = pvr_dbg_edm_open,
+       .read           = pvr_dbg_edm_read,
+       .release        = pvr_dbg_edm_release,
+};
+
 static int pvr_init_debugfs(void)
 {
        debugfs_dir = debugfs_create_dir("pvr", NULL);
@@ -337,6 +387,12 @@ static int pvr_init_debugfs(void)
                return -ENODEV;
        }
 
+       if (!debugfs_create_file("edm_trace", S_IRUGO, debugfs_dir, NULL,
+                                &pvr_dbg_edm_fops)) {
+               debugfs_remove_recursive(debugfs_dir);
+               return -ENODEV;
+       }
+
        return 0;
 }