ARM: tegra: Pass uncompress.h UART selection to DEBUG_LL

uncompress.h now saves the selected UART's physical address in Tegra's
IRAM, along with a cookie to indicate validity.

The first time it's run, macro addruart in debug-macro.S looks for this
cookie, and if it's present, uses the UART address stored there. If not,
the static value TEGRA_DEBUG_UART_BASE is used, as was previous behaviour.
The static behaviour will thus be used when not booting using a zImage.

This work was inspired by work by Doug Anderson <dianders@chromium.org>;
see http://lkml.org/lkml/2011/9/26/284. However, this patch relies on
the data passing describe above, rather than duplicating the UART
selection logic in debug-macro.S; the latest selection logic is more
complex due to the need to check reset/clock bits too.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Doug Anderson <dianders@chromium.org>
Acked-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Olof Johansson <olof@lixom.net>

1 files changed, 35 insertions, 0 deletions

diff --git a/arch/arm/mach-tegra/include/mach/irammap.h b/arch/arm/mach-tegra/include/mach/irammap.h
new file mode 100644
index 0000000..0cbe632
--- /dev/null
+++ b/arch/arm/mach-tegra/include/mach/irammap.h
@@ -0,0 +1,35 @@
+/*
+ * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __MACH_TEGRA_IRAMMAP_H
+#define __MACH_TEGRA_IRAMMAP_H
+
+#include <asm/sizes.h>
+
+/* The first 1K of IRAM is permanently reserved for the CPU reset handler */
+#define TEGRA_IRAM_RESET_HANDLER_OFFSET	0
+#define TEGRA_IRAM_RESET_HANDLER_SIZE	SZ_1K
+
+/*
+ * These locations are written to by uncompress.h, and read by debug-macro.S.
+ * The first word holds the cookie value if the data is valid. The second
+ * word holds the UART physical address.
+ */
+#define TEGRA_IRAM_DEBUG_UART_OFFSET	SZ_1K
+#define TEGRA_IRAM_DEBUG_UART_SIZE	8
+#define TEGRA_IRAM_DEBUG_UART_COOKIE	0x55415254
+
+#endif