vclog: Add DMA support (needed for Pi 3)

Pi 3 (BCM2710) has a 16MB hole in the ARM's address space where it can't see RAM because the I/O space is mapped there. This is the area where the firmware usually puts its logging information, so accessing it from the ARM requires the use of DMA to copy it to visible RAM. This major update adds DMA support, but also makes vclog more resilient when run in "follow" mode. Signed-off-by: Phil Elwell <phil@raspberrypi.com>
raspberrypi · Aug 9, 2023 · 94b89a6 · 94b89a6
1 parent 8fc892d
commit 94b89a6
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diff --git a/vclog/CMakeLists.txt b/vclog/CMakeLists.txt
@@ -6,5 +6,5 @@ set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -Wextra -Werror -pedantic")
 project(vclog)
 
 #add executables
-add_executable(vclog vcdbg.c)
+add_executable(vclog vclog.c)
 install(TARGETS vclog RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})