Introduce arch_phys_memset which works like memset but on physical memory

The default implementation of this function is just memset, but other
implementations will be needed when physical memory isn't accessible by
U-Boot using normal addressing mechanisms.

BUG=chrome-os-partner:7579
TEST=From the original, larger patch:
Built and booted on Lumpy, Stumpy, and Kaen. Looked at the log to see
that the regions in high memory are listed as cleared. Artificially injected
a range to "clear" with 0xA5 and then 0x5A which was over the framebuffer and
covered part or all of the screen on Lumpy. Verified that the screen was
partially or completely filled with an appropriate looking color. Had U-Boot
print the PDTs it was generating to verify that the high address bits were
preserved. Identity mapped only some of memory and verified that things that
should be mapped were accessible and things that shouldn't be weren't.

Signed-off-by: Gabe Black <gabeblack@google.com>

Change-Id: Ie1ba5bbb8ee2847f450d0057611deee397c316cf
Reviewed-on: https://gerrit.chromium.org/gerrit/14417
Reviewed-by: Gabe Black (Do Not Use) <gabeblack@google.com>
Tested-by: Gabe Black (Do Not Use) <gabeblack@google.com>

2 files changed, 25 insertions, 0 deletions

diff --git a/lib/Makefile b/lib/Makefile
index afa6914e1be..68b4828df38 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -45,6 +45,7 @@ COBJS-$(CONFIG_LMB) += lmb.o
 COBJS-y += ldiv.o
 COBJS-$(CONFIG_MD5) += md5.o
 COBJS-y += net_utils.o
+COBJS-y += physmem.o
 COBJS-y += qsort.o
 COBJS-$(CONFIG_SHA1) += sha1.o
 COBJS-$(CONFIG_SHA256) += sha256.o
diff --git a/lib/physmem.c b/lib/physmem.c
new file mode 100644
index 00000000000..0f035edcbe5
--- /dev/null
+++ b/lib/physmem.c
@@ -0,0 +1,24 @@
+/*
+ * Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ */
+
+#include <common.h>
+#include <physmem.h>
+
+static phys_addr_t __arch_phys_memset(phys_addr_t s, int c, phys_size_t n)
+{
+	void *s_ptr = (void *)(uintptr_t)s;
+
+	assert(((phys_addr_t)(uintptr_t)s) == s);
+	assert(((phys_addr_t)(uintptr_t)(s + n)) == s + n);
+	return (phys_addr_t)(uintptr_t)memset(s_ptr, c, n);
+}
+
+phys_addr_t arch_phys_memset(phys_addr_t s, int c, phys_size_t n)
+	__attribute__((weak, alias("__arch_phys_memset")));