ARM: tegra: decouple uncompress.h and debug-macro.S

Prior to this change, Tegra's debug-macro.S relied on uncompress.h having
determined which UART to use, and whether it was safe to use the UART
(i.e. is it not in reset, and is clocked). This determination was
communicated from uncompress.h to debug-macro.S using a few bytes of
Tegra's IRAM (an on-SoC RAM). This had the disadvantage that uncompress.h
was a required part of the kernel boot process; booting a non-compressed
kernel would not allow earlyprintk to operate.

This change duplicates the UART selection and validation logic into
debug-macro.S so that the reliance on uncompress.h is removed.

This also helps out with single-zImage work, since there is currently no
support for using any uncompress.h with single-zImage.

Signed-off-by: Stephen Warren <swarren@nvidia.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/arch/arm/mach-tegra/common.c b/arch/arm/mach-tegra/common.c
index 8b41e4c0d53f..bce8591cb72b 100644
--- a/arch/arm/mach-tegra/common.c
+++ b/arch/arm/mach-tegra/common.c
@@ -44,13 +44,15 @@
  * 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.
  */
-u32 tegra_uart_config[3] = {
+u32 tegra_uart_config[4] = {
 	/* Debug UART initialization required */
 	1,
 	/* Debug UART physical address */
 	0,
 	/* Debug UART virtual address */
 	0,
+	/* Scratch space for debug macro */
+	0,
 };
 
 #ifdef CONFIG_OF