Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/parisc/kernel/setup.c b/arch/parisc/kernel/setup.c
index 4e87c35..53a21ce 100644
--- a/arch/parisc/kernel/setup.c
+++ b/arch/parisc/kernel/setup.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  *    Initial setup-routines for HP 9000 based hardware.
  *
@@ -9,21 +10,6 @@
  *    Modifications copyright 2001 Ryan Bradetich <rbradetich@uswest.net>
  *
  *    Initial PA-RISC Version: 04-23-1999 by Helge Deller
- *
- *    This program is free software; you can redistribute it and/or modify
- *    it under the terms of the GNU General Public License as published by
- *    the Free Software Foundation; either version 2, or (at your option)
- *    any later version.
- *
- *    This program is distributed in the hope that it will be useful,
- *    but WITHOUT ANY WARRANTY; without even the implied warranty of
- *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *    GNU General Public License for more details.
- *
- *    You should have received a copy of the GNU General Public License
- *    along with this program; if not, write to the Free Software
- *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- *
  */
 
 #include <linux/kernel.h>
@@ -40,6 +26,7 @@
 #include <linux/sched/clock.h>
 #include <linux/start_kernel.h>
 
+#include <asm/cacheflush.h>
 #include <asm/processor.h>
 #include <asm/sections.h>
 #include <asm/pdc.h>
@@ -99,10 +86,6 @@
 
 	case pcxl2:
 		pa7300lc_init();
-	case pcxl: /* falls through */
-	case pcxs:
-	case pcxt:
-		hppa_dma_ops = &dma_noncoherent_ops;
 		break;
 	default:
 		break;
@@ -346,6 +329,13 @@
 			boot_cpu_data.cpu_hz / 1000000,
 			boot_cpu_data.cpu_hz % 1000000	);
 
+#if defined(CONFIG_64BIT) && defined(CONFIG_SMP)
+	/* Don't serialize TLB flushes if we run on one CPU only. */
+	if (num_online_cpus() == 1)
+		pa_serialize_tlb_flushes = 0;
+#endif
+
+	apply_alternatives_all();
 	parisc_setup_cache_timing();
 
 	/* These are in a non-obvious order, will fix when we have an iotree */
@@ -399,6 +389,9 @@
 	int ret, cpunum;
 	struct pdc_coproc_cfg coproc_cfg;
 
+	/* check QEMU/SeaBIOS marker in PAGE0 */
+	running_on_qemu = (memcmp(&PAGE0->pad0, "SeaBIOS", 8) == 0);
+
 	cpunum = smp_processor_id();
 
 	init_cpu_topology();