[PATCH v4 0/3] ARM: l2c: add l2c support for RZ/A1

Chris Brandt chris.brandt at renesas.com
Thu Feb 16 08:17:39 PST 2017


The PL310 in the Renesas RZ/A1 SoC (R7S72100) does not have the sideband
signals connected between the CPU and L2C. According the PL310 TRM,
sideband signals are optional.

If a PL310 is added to a system, but the sideband signals are not
connected, some Cortex A9 optimizations cannot be used. In particular,
enabling Full Line Zeros in the CA9 without sidebands connected will
crash the system since the CA9 will expect the L2C to perform operations,
yet the L2C never gets the commands.

This series adds the option to not enable anything in the PL310 that
uses sidebands, and then adds L2C support to the RZ/A1 DT.

v4:
* changed l2x0_bresp_dis to l2x0_bresp_disable
* changed l2x0_flz_dis to l2x0_flz_disable

v3:
* split "arm,pl310-no-sideband" into "arm,early-bresp-disable" and
  "arm,full-line-zero-disable"

v2:
* Added "arm,pl310-no-sideband" to cache-l2x0.c instead of hacking in a
  dummy l2c_write_sec function to keep FLZ from being enabled.


Chris Brandt (3):
  ARM: l2c: allow CA9 optimizations to be disabled
  ARM: shmobile: r7s72100: Enable L2 cache
  ARM: dts: r7s72100: add l2 cache

 Documentation/devicetree/bindings/arm/l2c2x0.txt |  3 +++
 arch/arm/boot/dts/r7s72100.dtsi                  | 11 +++++++++++
 arch/arm/mach-shmobile/setup-r7s72100.c          |  2 ++
 arch/arm/mm/cache-l2x0.c                         | 13 +++++++++++--
 4 files changed, 27 insertions(+), 2 deletions(-)

-- 
2.10.1





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