svn commit: r327667 - in stable/11/sys: arm/arm conf

[Ian Lepore]

Author: ian
Date: Sun Jan  7 02:57:35 2018
New Revision: 327667
URL: https://svnweb.freebsd.org/changeset/base/327667

Log:
  MFC r327222:
  
  Add a new ARM kernel option, LOCORE_MAP_MB, to control the size of the
  kernel VA mapping in the temporary page tables set up by locore-v6.S.
  
  The number used to be hard-coded to 64MB, which is still the default if
  the kernel option is not specified.  However, 64MB is insufficient for
  using a large mdroot filesystem.  The hard-coded number can't be safely
  increased because too large a number may run into memory-mapped IO space
  on some SoCs that must not be mapped as ordinary memory.

Modified:
  stable/11/sys/arm/arm/genassym.c
  stable/11/sys/arm/arm/locore-v6.S
  stable/11/sys/conf/options.arm
Directory Properties:
  stable/11/   (props changed)

Modified: stable/11/sys/arm/arm/genassym.c
==============================================================================
--- stable/11/sys/arm/arm/genassym.c	Sun Jan  7 02:30:08 2018	(r327666)
+++ stable/11/sys/arm/arm/genassym.c	Sun Jan  7 02:57:35 2018	(r327667)
@@ -161,3 +161,12 @@ ASSYM(DCACHE_LINE_SIZE, offsetof(struct cpuinfo, dcach
 ASSYM(DCACHE_LINE_MASK, offsetof(struct cpuinfo, dcache_line_mask));
 ASSYM(ICACHE_LINE_SIZE, offsetof(struct cpuinfo, icache_line_size));
 ASSYM(ICACHE_LINE_MASK, offsetof(struct cpuinfo, icache_line_mask));
+
+/*
+ * Emit the LOCORE_MAP_MB option as a #define only if the option was set.
+ */
+#include "opt_locore.h"
+
+#ifdef LOCORE_MAP_MB
+ASSYM(LOCORE_MAP_MB, LOCORE_MAP_MB);
+#endif

Modified: stable/11/sys/arm/arm/locore-v6.S
==============================================================================
--- stable/11/sys/arm/arm/locore-v6.S	Sun Jan  7 02:30:08 2018	(r327666)
+++ stable/11/sys/arm/arm/locore-v6.S	Sun Jan  7 02:57:35 2018	(r327667)
@@ -38,6 +38,10 @@
 
 __FBSDID("$FreeBSD$");
 
+/* We map 64MB of kernel unless overridden in assym.s by the kernel option. */
+#ifndef LOCORE_MAP_MB
+#define	LOCORE_MAP_MB	64
+#endif
 
 #if __ARM_ARCH >= 7
 #if defined(__ARM_ARCH_7VE__) || defined(__clang__)
@@ -172,12 +176,13 @@ ASENTRY_NP(_start)
 	bl	build_pagetables
 
 	/* 
-	 * Next we do 64MiB starting at the physical load address, mapped to
-	 * the VA the kernel is linked for.
+	 * Next we map the kernel starting at the physical load address, mapped
+	 * to the VA the kernel is linked for.  The default size we map is 64MiB
+	 * but it can be overridden with a kernel option.
 	 */
 	mov	r1, r5
 	ldr	r2, =(KERNVIRTADDR)
-	mov	r3, #64
+	ldr	r3, =(LOCORE_MAP_MB)
 	bl	build_pagetables
 
 	/* Create a device mapping for early_printf if specified. */

Modified: stable/11/sys/conf/options.arm
==============================================================================
--- stable/11/sys/conf/options.arm	Sun Jan  7 02:30:08 2018	(r327666)
+++ stable/11/sys/conf/options.arm	Sun Jan  7 02:57:35 2018	(r327667)
@@ -34,6 +34,7 @@ KERNVIRTADDR		opt_global.h
 LINUX_BOOT_ABI		opt_global.h
 LOADERRAMADDR		opt_global.h
 MULTIDELAY		opt_global.h
+LOCORE_MAP_MB		opt_locore.h
 PHYSADDR		opt_global.h
 PLATFORM		opt_global.h
 PLATFORM_SMP		opt_global.h