PM / devfreq: exynos: Add generic exynos bus frequency driver

This patch adds the generic exynos bus frequency driver for AMBA AXI bus
of sub-blocks in exynos SoC with DEVFREQ framework. The Samsung Exynos SoC
have the common architecture for bus between DRAM and sub-blocks in SoC.
This driver can support the generic bus frequency driver for Exynos SoCs.

In devicetree, Each bus block has a bus clock, regulator, operation-point
and devfreq-event devices which measure the utilization of each bus block.

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
[m.reichl and linux.amoon: Tested it on exynos4412-odroidu3 board]
Tested-by: Markus Reichl <m.reichl@fivetechno.de>
Tested-by: Anand Moon <linux.amoon@gmail.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Acked-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>

1 files changed, 15 insertions, 0 deletions

diff --git a/drivers/devfreq/Kconfig b/drivers/devfreq/Kconfig
index 4de78c552251..cedda8f1e5eb 100644
--- a/drivers/devfreq/Kconfig
+++ b/drivers/devfreq/Kconfig
@@ -66,6 +66,21 @@ config DEVFREQ_GOV_USERSPACE
 
 comment "DEVFREQ Drivers"
 
+config ARM_EXYNOS_BUS_DEVFREQ
+        bool "ARM EXYNOS Generic Memory Bus DEVFREQ Driver"
+        depends on ARCH_EXYNOS
+        select DEVFREQ_GOV_SIMPLE_ONDEMAND
+        select DEVFREQ_EVENT_EXYNOS_PPMU
+        select PM_DEVFREQ_EVENT
+        select PM_OPP
+        help
+          This adds the common DEVFREQ driver for Exynos Memory bus. Exynos
+          Memory bus has one more group of memory bus (e.g, MIF and INT block).
+          Each memory bus group could contain many memoby bus block. It reads
+          PPMU counters of memory controllers by using DEVFREQ-event device
+          and adjusts the operating frequencies and voltages with OPP support.
+          This does not yet operate with optimal voltages.
+
 config ARM_EXYNOS4_BUS_DEVFREQ
         bool "ARM Exynos4210/4212/4412 Memory Bus DEVFREQ Driver"
         depends on (CPU_EXYNOS4210 || SOC_EXYNOS4212 || SOC_EXYNOS4412) && !ARCH_MULTIPLATFORM