This patch converts exynos4_bus driver to use common PPMU code
(exynos_ppmu.c) instead of individual functions related to PPC
because PPMU is integrated module with both PPC and Bus event
generator.  When using PPMU to get bus performance read/write
event exynos4_bus driver deson't need to consider memory type.

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
[bzolnier: splitted out changes from the bigger patch]
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>

Exynos5-bus device devfreq driver monitors PPMU counters and
adjusts operating frequencies and voltages with OPP. ASV should
be used to provide appropriate voltages as per the speed group
of the SoC rather than using a constant 1.025V.

Signed-off-by: Abhilash Kesavan <a.kesavan@samsung.com>
[myungjoo.ham@samsung.com: minor style update]
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Cc: Jonghwan Choi <jhbird.choi@samsung.com>
Cc: Kukjin Kim <kgene.kim@samsung.com>

In anticipation of the new exynos5 devfreq and ppmu driver, create
an exynos sub-directory. Move the existing exynos4 devfreq driver
into the same.

Signed-off-by: Abhilash Kesavan <a.kesavan@samsung.com>
Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Cc: Jonghwan Choi <jhbird.choi@samsung.com>
Cc: Kukjin Kim <kgene.kim@samsung.com>