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>

arch/arm/mach-tegra/common.c

@@ -33,6 +33,23 @@
 #include "clock.h"
 #include "fuse.h"
 
+/*
+ * Storage for debug-macro.S's state.
+ *
+ * This must be in .data not .bss so that it gets initialized each time the
+ * kernel is loaded. The data is declared here rather than debug-macro.S so
+ * that multiple inclusions of debug-macro.S point at the same data.
+ */
+#define TEGRA_DEBUG_UART_OFFSET (TEGRA_DEBUG_UART_BASE & 0xFFFF)
+u32 tegra_uart_config[3] = {
+	/* Debug UART initialization required */
+	1,
+	/* Debug UART physical address */
+	(u32)(IO_APB_PHYS + TEGRA_DEBUG_UART_OFFSET),
+	/* Debug UART virtual address */
+	(u32)(IO_APB_VIRT + TEGRA_DEBUG_UART_OFFSET),
+};
+
 #ifdef CONFIG_OF
 static const struct of_device_id tegra_dt_irq_match[] __initconst = {
 	{ .compatible = "arm,cortex-a9-gic", .data = gic_of_init },