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| author |   Pali Rohár <pali@kernel.org> | 2022-08-23 01:15:01 +0200 |
|---|---|---|
| committer |   Michael Ellerman <mpe@ellerman.id.au> | 2022-09-28 19:22:09 +1000 |
| commit | b19448fe846baad689ff51a991ebfc74b4b5e0a8 (patch) | |
| tree | e3cbb5f13d2ff44608a50a537191bf82ece17da9 /arch/powerpc/Kconfig.debug | |
| parent | powerpc/64/kdump: Limit kdump base to 512MB (diff) | |
| download | linux-dev-b19448fe846baad689ff51a991ebfc74b4b5e0a8.tar.xz linux-dev-b19448fe846baad689ff51a991ebfc74b4b5e0a8.zip | |
powerpc: Add support for early debugging via Serial 16550 console
Currently powerpc early debugging contains lot of platform specific
options, but does not support standard UART / serial 16550 console.
Later legacy_serial.c code supports registering UART as early debug console
from device tree but it is not early during booting, but rather later after
machine description code finishes.
So for real early debugging via UART is current code unsuitable.
Add support for new early debugging option CONFIG_PPC_EARLY_DEBUG_16550
which enable Serial 16550 console on address defined by new option
CONFIG_PPC_EARLY_DEBUG_16550_PHYSADDR and by stride by option
CONFIG_PPC_EARLY_DEBUG_16550_STRIDE.
With this change it is possible to debug powerpc machine descriptor code.
For example this early debugging code can print on serial console also
"No suitable machine description found" error which is done before
legacy_serial.c code.
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220822231501.16827-1-pali@kernel.org
Diffstat (limited to 'arch/powerpc/Kconfig.debug')
| -rw-r--r-- | arch/powerpc/Kconfig.debug | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/arch/powerpc/Kconfig.debug b/arch/powerpc/Kconfig.debug index ae727d4218b9..6aaf8dc60610 100644 --- a/arch/powerpc/Kconfig.debug +++ b/arch/powerpc/Kconfig.debug @@ -283,6 +283,12 @@ config PPC_EARLY_DEBUG_MEMCONS This console provides input and output buffers stored within the kernel BSS and should be safe to select on any system. A debugger can then be used to read kernel output or send input to the console. + +config PPC_EARLY_DEBUG_16550 + bool "Serial 16550" + depends on PPC_UDBG_16550 + help + Select this to enable early debugging via Serial 16550 console endchoice config PPC_MEMCONS_OUTPUT_SIZE @@ -354,6 +360,15 @@ config PPC_EARLY_DEBUG_CPM_ADDR platform probing is done, all platforms selected must share the same address. +config PPC_EARLY_DEBUG_16550_PHYSADDR + hex "Early debug Serial 16550 physical address" + depends on PPC_EARLY_DEBUG_16550 + +config PPC_EARLY_DEBUG_16550_STRIDE + int "Early debug Serial 16550 stride" + depends on PPC_EARLY_DEBUG_16550 + default 1 + config FAIL_IOMMU bool "Fault-injection capability for IOMMU" depends on FAULT_INJECTION |