[meta-freescale] Should all T4240 errata be applied to T1040?
Bob Cochran
yocto at mindchasers.com
Wed Sep 17 20:43:57 PDT 2014
I find that during initialization of my T1040rdb-64b using the kernel
built with meta-fsl-ppc master, the FMBM_CFG2.TNTASKS field (total
number of BMI tasks) is being overwritten to 0x7b (the reset value is
documented as 0x3b in the T1040 reference manual).
I believe this is being overwritten due to sharing the errata
definitions with the T4240, but this particular erratum may not apply to
the T1040 and may cause undesirable side effects.
The T4240 uses DPAA FMAN_v3H, and the T1040 uses DPAA FMAN_v3L.
Here is my understanding of how this erratum (A005127) is being applied
to the T1040:
1) t1040_64bit_smp_defconfig defines CONFIG_FMAN_T4240
2) By defining CONFIG_FMAN_T4240,
drivers/net/ethernet/freescale/fman/ncsw_config.mk adds
-I$(FMAN)/inc/integrations/T4240 to EXTRA_CFLAGS.
3) dpaa_integration_ext.h is included throughout the fman source files
from drivers/net/ethernet/freescale/fman/inc/integrations/T4240
4) This defines FM_WRONG_RESET_VALUES_ERRATA_FMAN_A005127, but it is my
understanding that this erratum does not apply to the T1040.
5) This results in FMBM_CFG2.TNTASKS being overwritten with a value
approximately twice its default value, and my concern is that the
FMAN_V3L does not have the resources to support this many tasks.
In general, I'm also wondering whether the other errata in the
integration file is appropriate for the T1040 and whether the FMAN_v3L
devices should have their own integration tree.
More information about the meta-freescale
mailing list