lib: utils: Improve fdt_timer

[platform/kernel/opensbi.git] / lib / utils / timer / fdt_timer.c

diff --git a/lib/utils/timer/fdt_timer.c b/lib/utils/timer/fdt_timer.c
index 4695c0f..62426a7 100644 (file)
--- a/lib/utils/timer/fdt_timer.c
+++ b/lib/utils/timer/fdt_timer.c
@@ -16,24 +16,17 @@
 extern struct fdt_timer *fdt_timer_drivers[];
 extern unsigned long fdt_timer_drivers_size;
 
-static struct fdt_timer dummy = {
-       .match_table = NULL,
-       .cold_init = NULL,
-       .warm_init = NULL,
-       .exit = NULL,
-};
-
-static struct fdt_timer *current_driver = &dummy;
+static struct fdt_timer *current_driver = NULL;
 
 void fdt_timer_exit(void)
 {
-       if (current_driver->exit)
+       if (current_driver && current_driver->exit)
                current_driver->exit();
 }
 
 static int fdt_timer_warm_init(void)
 {
-       if (current_driver->warm_init)
+       if (current_driver && current_driver->warm_init)
                return current_driver->warm_init();
        return 0;
 }
@@ -51,20 +44,28 @@ static int fdt_timer_cold_init(void)
                noff = -1;
                while ((noff = fdt_find_match(fdt, noff,
                                        drv->match_table, &match)) >= 0) {
-                       if (drv->cold_init) {
-                               rc = drv->cold_init(fdt, noff, match);
-                               if (rc == SBI_ENODEV)
-                                       continue;
-                               if (rc)
-                                       return rc;
-                       }
+                       /* drv->cold_init must not be NULL */
+                       if (drv->cold_init == NULL)
+                               return SBI_EFAIL;
+
+                       rc = drv->cold_init(fdt, noff, match);
+                       if (rc == SBI_ENODEV)
+                               continue;
+                       if (rc)
+                               return rc;
                        current_driver = drv;
-               }
 
-               if (current_driver != &dummy)
-                       break;
+                       /*
+                        * We will have multiple timer devices on multi-die or
+                        * multi-socket systems so we cannot break here.
+                        */
+               }
        }
 
+       /*
+        * We can't fail here since systems with Sstc might not provide
+        * mtimer/clint DT node in the device tree.
+        */
        return 0;
 }