error: impossible constraint in ‘asm’ asm volatile("rdtscp" : "=a" (low), "=d" (high)) for ARM64

[jumpmanhou]

I try to build the QDMA driver for the ARM64 arch, but there is an error, here is the error log:
#######################

Driver

#######################
make -C driver modulesymfile=/home/m1_sw/chunpeng/dma_ip_drivers/QDMA/linux-kernel/driver/src/Module.symvers
make[1]: Entering directory '/home/m1_sw/chunpeng/dma_ip_drivers/QDMA/linux-kernel/driver'
"distro=, dmajor= dminor= "
5.10.134-15852-gf17a528bd1c2-dirty: GIT,,, -DGITSP -DGIT
CROSS_COMPILE_FLAG = .
ARCH = aarch64.
#######################

PF src

#######################
make[2]: Entering directory '/home/m1_sw/chunpeng/dma_ip_drivers/QDMA/linux-kernel/driver/src'
srcdir = /home/m1_sw/chunpeng/dma_ip_drivers/QDMA/linux-kernel/driver/src.
KSRC = /home/m1_sw/chunpeng/kernel-5.10.
VF = 0.
CROSS_COMPILE_FLAG = .
ARCH = aarch64.
EXTRA_FLAGS = .
ccflags-y = .
make[3]: Entering directory '/home/m1_sw/chunpeng/kernel-5.10'
srcdir = /home/m1_sw/chunpeng/dma_ip_drivers/QDMA/linux-kernel/driver/src.
KSRC = /home/m1_sw/chunpeng/kernel-5.10.
VF = 0.
CROSS_COMPILE_FLAG = .
ARCH = arm64.
EXTRA_FLAGS = .
ccflags-y = .
CC [M] /home/m1_sw/chunpeng/dma_ip_drivers/QDMA/linux-kernel/driver/src/libqdma/qdma_descq.o
/home/m1_sw/chunpeng/dma_ip_drivers/QDMA/linux-kernel/driver/src/libqdma/qdma_descq.c: In function ‘rdtsc_gettime’:
/home/m1_sw/chunpeng/dma_ip_drivers/QDMA/linux-kernel/driver/src/libqdma/qdma_descq.c:68:2: error: impossible constraint in ‘asm’
asm volatile("rdtscp" : "=a" (low), "=d" (high));
^~~
make[4]: *** [scripts/Makefile.build:286: /home/m1_sw/chunpeng/dma_ip_drivers/QDMA/linux-kernel/driver/src/libqdma/qdma_descq.o] Error 1
make[3]: *** [Makefile:1831: /home/m1_sw/chunpeng/dma_ip_drivers/QDMA/linux-kernel/driver/src] Error 2
make[3]: Leaving directory '/home/m1_sw/chunpeng/kernel-5.10'
make[2]: *** [Makefile:135: bin] Error 2
make[2]: Leaving directory '/home/m1_sw/chunpeng/dma_ip_drivers/QDMA/linux-kernel/driver/src'
make[1]: *** [Makefile:206: mod_pf] Error 2
make[1]: Leaving directory '/home/m1_sw/chunpeng/dma_ip_drivers/QDMA/linux-kernel/driver'
make: *** [Makefile:94: driver] Error 2

Does this driver support on ARM64 platform?

[hmaarrfk]

No it does not to my knowledge.

Xilinx doesn't like to answer on github. if you want to go through the upgrade collaboratively, I'll help review and move you along when i can:

https://github.com/hmaarrfk/dma_ip_drivers/

[jumpmanhou]

Thanks, mark. The "rdtscp" is X86 instruction, I modified the function according to this link:https://lore.kernel.org/lkml/20200914115311.2201-3-leo.yan@linaro.org/ and it worked.