drivers: soc: sifive: add basic L2 cache controller driver

SiFive SoCs are cache coherent with respect to other DMA masters,
so there is no need to explicitly flush cache lines.
Incoming StarFive SoC uses SiFive CPU and L2 cache controller,
but is cache-incoherent and thus needs the maintenance for DMA.

Add a basic driver that exports the cache flush function for
SoC-specific drivers to use.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Link: https://lore.barebox.org/20210619045055.779-13-a.fatoum@pengutronix.de
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

1 files changed, 4 insertions, 0 deletions

diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile
new file mode 100644
index 0000000000..b787379586
--- /dev/null
+++ b/drivers/soc/Makefile
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
+
+obj-y	+= imx/
+obj-$(CONFIG_CPU_SIFIVE)	+= sifive/