[PATCH 0/4] ARM: tegra: Automatic UART selection for earlyprintk
Stephen Warren
swarren at nvidia.com
Tue Jan 3 17:25:16 EST 2012
This series allows a Tegra zImage to automatically select the UART to use
for the zImage decompressor and early printk, based on information from
the bootloader. The code scans each UART, looking for one that is clocked,
is out of reset, and that the bootloader has written 'D' (for 'D'ebug) to
the scratch register.
At present, the ChromiumOS branch of U-Boot sets up UARTs in this way. If
this patch is accepted into the kernel, I'll upstream the U-Boot change to
mainline U-Boot.
This is important, since different boards use different UARTs, and it's
nice not to have to configure the kernel differently when switching
boards.
This patch series depends on patch "[PATCH V2] arm/tegra: Support Tegra30
in decompressor UART setup" for context.
Doug Anderson (2):
ARM: tegra: Introduce define DEBUG_UART_SHIFT
ARM: tegra: uncompress.h: Store UART address in a variable
Stephen Warren (2):
ARM: tegra: uncompress.h: Choose a UART at runtime
ARM: tegra: Pass uncompress.h UART selection to DEBUG_LL
arch/arm/mach-tegra/common.c | 17 ++++
arch/arm/mach-tegra/include/mach/debug-macro.S | 87 +++++++++++++++++---
arch/arm/mach-tegra/include/mach/uncompress.h | 108 +++++++++++++++++++++---
3 files changed, 190 insertions(+), 22 deletions(-)
More information about the linux-arm-kernel
mailing list