Thanks to Jason Zhao we got a skeleton CAR code for VIA C7. I have tried
to clean it up a bit and find justifications for every difference from
x86 and AMD CAR code. I believe this is mostly merge-ready. Although I'd
have preferred to do this for v3 first, we can fix v2 boards with this
change and then move them to v3.
Thanks to Bari Ari for getting the code to me for rewrite/review.

CONFIG_CARTEST shall not be enabled (breaks the build).

Signed-off-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
Signed-off-by: Jason Zhao <jasonzhao@viatech.com.cn>
Acked-by: Ronald G. Minnich <rminnich@gmail.com>
Acked-by: Uwe Hermann <uwe@hermann-uwe.de>


git-svn-id: svn://svn.coreboot.org/coreboot/trunk@3634 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1
diff --git a/src/cpu/via/car/cache_as_ram.inc b/src/cpu/via/car/cache_as_ram.inc
new file mode 100644
index 0000000..3bd4046
--- /dev/null
+++ b/src/cpu/via/car/cache_as_ram.inc
@@ -0,0 +1,172 @@
+/* 
+ * This file is part of the coreboot project.
+ * 
+ * Copyright (C) 2000,2007 Ronald G. Minnich <rminnich@gmail.com>
+ * Copyright (C) 2005 Eswar Nallusamy, LANL
+ * Copyright (C) 2005 Tyan
+ * (Written by Yinghai Lu <yhlu@tyan.com> for Tyan)
+ * Copyright (C) 2007 coresystems GmbH
+ * (Written by Stefan Reinauer <stepan@coresystems.de> for coresystems GmbH)
+ * Copyright (C) 2007,2008 Carl-Daniel Hailfinger
+ * Copyright (C) 2008 VIA Technologies, Inc.
+ * (Written by Jason Zhao <jasonzhao@viatech.com.cn> for VIA)
+ * 
+ * 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; version 2 of the License.
+ * 
+ * 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., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
+ */
+
+#define	CacheSize DCACHE_RAM_SIZE
+#define	CacheBase DCACHE_RAM_BASE
+
+
+#include	<cpu/x86/mtrr.h>
+
+	/* Save the BIST result */
+	movl    %eax, %ebp
+
+CacheAsRam:
+
+	/* disable cache */
+	movl    %cr0, %eax
+	orl    $(0x1<<30),%eax
+	movl    %eax,%cr0
+	invd
+
+	/* Set the default memory type and enable fixed and variable MTRRs */
+	movl    $MTRRdefType_MSR, %ecx
+	xorl    %edx, %edx
+	/* Enable Variable and Fixed MTRRs */
+	movl    $0x00000c00, %eax
+	wrmsr
+
+	/* Clear all MTRRs */
+	xorl    %edx, %edx
+	movl    $fixed_mtrr_msr, %esi
+clear_fixed_var_mtrr:
+	lodsl   (%esi), %eax
+	testl   %eax, %eax
+	jz      clear_fixed_var_mtrr_out
+
+	movl    %eax, %ecx
+	xorl    %eax, %eax
+	wrmsr
+
+	jmp     clear_fixed_var_mtrr
+clear_fixed_var_mtrr_out:
+	/* MTRRPhysBase */
+	movl    $0x200, %ecx
+	xorl    %edx, %edx
+	movl    $(CacheBase|MTRR_TYPE_WRBACK),%eax
+	wrmsr
+
+	/* MTRRPhysMask */
+	movl    $0x201, %ecx
+	/* This assumes we never access addresses above 2^36 in CAR. */
+	movl    $0x0000000f,%edx
+	movl    $(~(CacheSize-1)|0x800),%eax
+	wrmsr
+
+        /* enable write base caching so we can do execute in place
+         * on the flash rom.
+         */
+	/* MTRRPhysBase */
+	movl    $0x202, %ecx
+	xorl    %edx, %edx
+	movl    $(XIP_ROM_BASE|MTRR_TYPE_WRBACK),%eax
+	wrmsr
+
+	/* MTRRPhysMask */
+	movl    $0x203, %ecx
+	movl    $0x0000000f,%edx
+	movl    $(~(XIP_ROM_SIZE - 1) | 0x800), %eax
+	wrmsr
+
+
+	movl    $MTRRdefType_MSR, %ecx
+	xorl    %edx, %edx
+	/* Enable Variable and Fixed MTRRs */
+	movl    $0x00000800, %eax
+	wrmsr
+
+	movl    %cr0, %eax
+	andl    $0x9fffffff,%eax
+	movl    %eax, %cr0
+
+	/* Read the range with lodsl*/
+	cld
+	movl    $CacheBase, %esi
+	movl    %esi, %edi
+	movl    $(CacheSize>>2), %ecx
+	rep     lodsl
+
+	movl    $CacheBase, %esi
+	movl    %esi, %edi
+	movl    $(CacheSize>>2), %ecx
+
+	/* 0x5c5c5c5c is a memory test pattern.
+         * TODO: Check if everything works with the zero pattern as well. */
+	/*xorl    %eax, %eax*/
+	xorl    $0x5c5c5c5c,%eax
+	rep     stosl
+
+	movl    XIP_ROM_BASE, %esi
+	movl    %esi, %edi
+	movl    $(XIP_ROM_SIZE>>2), %ecx
+	rep     lodsl
+
+	/* The key point of this CAR code is C7 cache does not turn into
+	 * "no fill" mode, which is not compatible with general CAR code.
+	 */
+
+	movl    $(CacheBase+CacheSize-4), %eax
+	movl    %eax, %esp
+
+#ifdef CONFIG_CARTEST
+testok:	movb $0x40,%al
+	outb %al, $0x80
+	xorl  %edx, %edx
+	xorl  %eax, %eax
+	movl  $0x5c5c,%edx
+	pushl %edx
+	pushl %edx
+	pushl %edx
+	pushl %edx
+	pushl %edx
+	popl  %esi
+	popl  %esi
+	popl  %eax
+	popl  %eax
+	popl  %eax
+	cmpl %edx,%eax
+	jne stackerr
+#endif
+
+	/* Restore the BIST result */
+	movl	%ebp, %eax
+	/* We need to set ebp ? No need */
+	movl	%esp, %ebp
+	pushl 	%eax  /* bist */
+	call    amd64_main
+	/* We will not go back */
+
+fixed_mtrr_msr:
+	.long	0x250, 0x258, 0x259
+	.long	0x268, 0x269, 0x26A
+	.long	0x26B, 0x26C, 0x26D
+	.long	0x26E, 0x26F
+var_mtrr_msr:
+	.long	0x200, 0x201, 0x202, 0x203
+	.long	0x204, 0x205, 0x206, 0x207
+	.long	0x208, 0x209, 0x20A, 0x20B
+	.long	0x20C, 0x20D, 0x20E, 0x20F
+	.long	0x000 /* NULL, end of table */
diff --git a/src/cpu/via/car/cache_as_ram.lds b/src/cpu/via/car/cache_as_ram.lds
new file mode 100644
index 0000000..f55adf4
--- /dev/null
+++ b/src/cpu/via/car/cache_as_ram.lds
@@ -0,0 +1,31 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2008 Carl-Daniel Hailfinger
+ *
+ * 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 of the License, 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., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
+ */
+
+SECTIONS {
+	.init . : {
+		_init = .;
+		*(.init.text);
+		*(.init.rodata);
+		*(.init.rodata.*);
+		. = ALIGN(16);
+		_einit = .;
+	}
+
+}