- Update to 3.3-rc2.

[linux-flexiantxendom0-3.2.10.git] / arch / powerpc / kernel / legacy_serial.c

diff --git a/arch/powerpc/kernel/legacy_serial.c b/arch/powerpc/kernel/legacy_serial.c
index bedd12e..508c093 100644 (file)
--- a/arch/powerpc/kernel/legacy_serial.c
+++ b/arch/powerpc/kernel/legacy_serial.c
@@ -527,6 +527,55 @@ device_initcall(serial_dev_init);
 
 
 #ifdef CONFIG_SERIAL_8250_CONSOLE
+#if defined(CONFIG_PPC_PSERIES) && defined(CONFIG_SERIAL_8250_CONSOLE)
+/*
+ * Handle the SysRq ^O Hack also via ttyS0 on POWER4 systems
+ * but only on the system console, see asm/serial.h
+ * If they run in FullSystemPartition mode, the firmware console comes in via ttyS0
+ * But BREAK does not work via the HMC, to trigger sysrq.
+ * The same is required for Cell blades
+ */
+int do_sysrq_via_ctrl_o;
+static const char __initdata *need_ctrl_o[] = {
+       "IBM,079", /* QS2x */
+       "IBM,0792-32G", /* QS21 */
+       "IBM,0793-2RZ", /* QS22 */
+       "IBM,7040-681", /* p690 */
+       "IBM,7040-671", /* p670 */
+       "IBM,7039-651", /* p655 */
+       "IBM,7038-6M2", /* p650 */
+       "IBM,7028-6E4", /* p630 tower */
+       "IBM,7028-6C4", /* p630 rack */
+       "IBM,7029-6E3", /* p615 tower */
+       "IBM,7029-6C3", /* p615 rack */
+       NULL
+};
+static void __init detect_need_for_ctrl_o(void)
+{
+       struct device_node *root;
+       const char *model, *p;
+       int i;
+
+       root = of_find_node_by_path("/");
+       if (!root)
+               return;
+       model = of_get_property(root, "model", NULL);
+       if (model) {
+               i = 0;
+               while (need_ctrl_o[i]) {
+                       p = need_ctrl_o[i];
+                       if (strncmp(p, model, strlen(p)) == 0) {
+                               do_sysrq_via_ctrl_o = 1;
+                               DBG("Enable sysrq via CTRL o on model %s\n", model);
+                               break;
+                       }
+                       i++;
+               }
+       }
+       of_node_put(root);
+}
+#endif
+
 /*
  * This is called very early, as part of console_init() (typically just after
  * time_init()). This function is respondible for trying to find a good
@@ -595,6 +644,9 @@ static int __init check_legacy_serial_console(void)
        if (i >= legacy_serial_count)
                goto not_found;
 
+#if defined(CONFIG_PPC_PSERIES) && defined(CONFIG_SERIAL_8250_CONSOLE)
+       detect_need_for_ctrl_o();
+#endif
        of_node_put(prom_stdout);
 
        DBG("Found serial console at ttyS%d\n", offset);