[PATCH v4 1/8] clk: samsung: add needed IDs for DMC clocks in Exynos5420

[PATCH v4 1/8] clk: samsung: add needed IDs for DMC clocks in Exynos5420

[Lukasz Luba]

Define new IDs for clocks used by Dynamic Memory Controller in
Exynos5422 SoC.

Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
---
 include/dt-bindings/clock/exynos5420.h | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/include/dt-bindings/clock/exynos5420.h b/include/dt-bindings/clock/exynos5420.h
index 355f469..0d00fbb 100644
--- a/include/dt-bindings/clock/exynos5420.h
+++ b/include/dt-bindings/clock/exynos5420.h
@@ -60,6 +60,7 @@
 #define CLK_MAU_EPLL		159
 #define CLK_SCLK_HSIC_12M	160
 #define CLK_SCLK_MPHY_IXTAL24	161
+#define CLK_SCLK_BPLL		162
 
 /* gate clocks */
 #define CLK_UART0		257
@@ -195,6 +196,16 @@
 #define CLK_ACLK432_CAM		518
 #define CLK_ACLK_FL1550_CAM	519
 #define CLK_ACLK550_CAM		520
+#define CLK_CLKM_PHY0		521
+#define CLK_CLKM_PHY1		522
+#define CLK_ACLK_PPMU_DREX0_0	523
+#define CLK_ACLK_PPMU_DREX0_1	524
+#define CLK_ACLK_PPMU_DREX1_0	525
+#define CLK_ACLK_PPMU_DREX1_1	526
+#define CLK_PCLK_PPMU_DREX0_0	527
+#define CLK_PCLK_PPMU_DREX0_1	528
+#define CLK_PCLK_PPMU_DREX1_0	529
+#define CLK_PCLK_PPMU_DREX1_1	530
 
 /* mux clocks */
 #define CLK_MOUT_HDMI		640
@@ -217,6 +228,8 @@
 #define CLK_MOUT_EPLL		657
 #define CLK_MOUT_MAU_EPLL	658
 #define CLK_MOUT_USER_MAU_EPLL	659
+#define CLK_MOUT_SCLK_SPLL	660
+#define CLK_MOUT_MX_MSPLL_CCORE_PHY	661
 
 /* divider clocks */
 #define CLK_DOUT_PIXEL		768
@@ -248,8 +261,9 @@
 #define CLK_DOUT_CCLK_DREX0	794
 #define CLK_DOUT_CLK2X_PHY0	795
 #define CLK_DOUT_PCLK_CORE_MEM	796
+#define CLK_FF_DOUT_SPLL2	797
 
 /* must be greater than maximal clock id */
-#define CLK_NR_CLKS		797
+#define CLK_NR_CLKS		798
 
 #endif /* _DT_BINDINGS_CLOCK_EXYNOS_5420_H */
-- 
2.7.4


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Re: [PATCH v4 1/8] clk: samsung: add needed IDs for DMC clocks in Exynos5420

[Rob Herring]

On Fri, Feb 01, 2019 at 05:46:45PM +0100, Lukasz Luba wrote:
> Define new IDs for clocks used by Dynamic Memory Controller in
> Exynos5422 SoC.
> 
> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
> ---
>  include/dt-bindings/clock/exynos5420.h | 16 +++++++++++++++-
>  1 file changed, 15 insertions(+), 1 deletion(-)

Acked-by: Rob Herring <robh@kernel.org>

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[PATCH v4 2/8] clk: samsung: add new clocks for DMC for Exynos5422 SoC

[Lukasz Luba]

This patch provides support for clocks needed for Dynamic Memory Controller
in Exynos5422 SoC. It adds CDREX base register addresses, new DIV, MUX and
GATE entries.

Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
---
 drivers/clk/samsung/clk-exynos5420.c | 46 ++++++++++++++++++++++++++++++++----
 1 file changed, 42 insertions(+), 4 deletions(-)

diff --git a/drivers/clk/samsung/clk-exynos5420.c b/drivers/clk/samsung/clk-exynos5420.c
index 34cce3c..f1a4f56 100644
--- a/drivers/clk/samsung/clk-exynos5420.c
+++ b/drivers/clk/samsung/clk-exynos5420.c
@@ -132,6 +132,8 @@
 #define BPLL_LOCK		0x20010
 #define BPLL_CON0		0x20110
 #define SRC_CDREX		0x20200
+#define GATE_BUS_CDREX0		0x20700
+#define GATE_BUS_CDREX1		0x20704
 #define DIV_CDREX0		0x20500
 #define DIV_CDREX1		0x20504
 #define KPLL_LOCK		0x28000
@@ -248,6 +250,8 @@ static const unsigned long exynos5x_clk_regs[] __initconst = {
 	DIV_CDREX1,
 	SRC_KFC,
 	DIV_KFC0,
+	GATE_BUS_CDREX0,
+	GATE_BUS_CDREX1,
 };
 
 static const unsigned long exynos5800_clk_regs[] __initconst = {
@@ -425,6 +429,10 @@ PNAME(mout_group13_5800_p)	= { "dout_osc_div", "mout_sw_aclkfl1_550_cam" };
 PNAME(mout_group14_5800_p)	= { "dout_aclk550_cam", "dout_sclk_sw" };
 PNAME(mout_group15_5800_p)	= { "dout_osc_div", "mout_sw_aclk550_cam" };
 PNAME(mout_group16_5800_p)	= { "dout_osc_div", "mout_mau_epll_clk" };
+PNAME(mout_mx_mspll_ccore_phy_p) = { "sclk_bpll", "mout_sclk_dpll",
+					"mout_sclk_mpll", "ff_dout_spll2",
+					"mout_sclk_spll", "mout_sclk_epll"};
+
 
 /* fixed rate clocks generated outside the soc */
 static struct samsung_fixed_rate_clock
@@ -450,7 +458,7 @@ static const struct samsung_fixed_factor_clock
 static const struct samsung_fixed_factor_clock
 		exynos5800_fixed_factor_clks[] __initconst = {
 	FFACTOR(0, "ff_dout_epll2", "mout_sclk_epll", 1, 2, 0),
-	FFACTOR(0, "ff_dout_spll2", "mout_sclk_spll", 1, 2, 0),
+	FFACTOR(CLK_FF_DOUT_SPLL2, "ff_dout_spll2", "mout_sclk_spll", 1, 2, 0),
 };
 
 static const struct samsung_mux_clock exynos5800_mux_clks[] __initconst = {
@@ -472,11 +480,14 @@ static const struct samsung_mux_clock exynos5800_mux_clks[] __initconst = {
 	MUX(0, "mout_aclk300_disp1", mout_group5_5800_p, SRC_TOP2, 24, 2),
 	MUX(0, "mout_aclk300_gscl", mout_group5_5800_p, SRC_TOP2, 28, 2),
 
+	MUX(CLK_MOUT_MX_MSPLL_CCORE_PHY, "mout_mx_mspll_ccore_phy",
+		mout_mx_mspll_ccore_phy_p, SRC_TOP7, 0, 3),
+
 	MUX(CLK_MOUT_MX_MSPLL_CCORE, "mout_mx_mspll_ccore",
-			mout_mx_mspll_ccore_p, SRC_TOP7, 16, 2),
+			mout_mx_mspll_ccore_p, SRC_TOP7, 16, 3),
 	MUX_F(CLK_MOUT_MAU_EPLL, "mout_mau_epll_clk", mout_mau_epll_clk_5800_p,
 			SRC_TOP7, 20, 2, CLK_SET_RATE_PARENT, 0),
-	MUX(0, "sclk_bpll", mout_bpll_p, SRC_TOP7, 24, 1),
+	MUX(CLK_SCLK_BPLL, "sclk_bpll", mout_bpll_p, SRC_TOP7, 24, 1),
 	MUX(0, "mout_epll2", mout_epll2_5800_p, SRC_TOP7, 28, 1),
 
 	MUX(0, "mout_aclk550_cam", mout_group3_5800_p, SRC_TOP8, 16, 3),
@@ -648,7 +659,7 @@ static const struct samsung_mux_clock exynos5x_mux_clks[] __initconst = {
 
 	MUX(0, "mout_sclk_mpll", mout_mpll_p, SRC_TOP6, 0, 1),
 	MUX(CLK_MOUT_VPLL, "mout_sclk_vpll", mout_vpll_p, SRC_TOP6, 4, 1),
-	MUX(0, "mout_sclk_spll", mout_spll_p, SRC_TOP6, 8, 1),
+	MUX(CLK_MOUT_SCLK_SPLL, "mout_sclk_spll", mout_spll_p, SRC_TOP6, 8, 1),
 	MUX(0, "mout_sclk_ipll", mout_ipll_p, SRC_TOP6, 12, 1),
 	MUX(0, "mout_sclk_rpll", mout_rpll_p, SRC_TOP6, 16, 1),
 	MUX_F(CLK_MOUT_EPLL, "mout_sclk_epll", mout_epll_p, SRC_TOP6, 20, 1,
@@ -817,6 +828,8 @@ static const struct samsung_div_clock exynos5x_div_clks[] __initconst = {
 	DIV(CLK_DOUT_CLK2X_PHY0, "dout_clk2x_phy0", "dout_sclk_cdrex",
 			DIV_CDREX0, 3, 5),
 
+	DIV(0, "dout_pclk_drex0", "dout_cclk_drex0", DIV_CDREX0, 28, 3),
+
 	DIV(CLK_DOUT_PCLK_CORE_MEM, "dout_pclk_core_mem", "mout_mclk_cdrex",
 			DIV_CDREX1, 8, 3),
 
@@ -1170,6 +1183,31 @@ static const struct samsung_gate_clock exynos5x_gate_clks[] __initconst = {
 			GATE_TOP_SCLK_ISP, 12, CLK_SET_RATE_PARENT, 0),
 
 	GATE(CLK_G3D, "g3d", "mout_user_aclk_g3d", GATE_IP_G3D, 9, 0, 0),
+
+	GATE(CLK_CLKM_PHY0, "clkm_phy0", "dout_sclk_cdrex",
+			GATE_BUS_CDREX0, 0, 0, 0),
+	GATE(CLK_CLKM_PHY1, "clkm_phy1", "dout_sclk_cdrex",
+			GATE_BUS_CDREX0, 1, 0, 0),
+	GATE(0, "mx_mspll_ccore_phy", "mout_mx_mspll_ccore_phy",
+			SRC_MASK_TOP7, 0, CLK_IGNORE_UNUSED, 0),
+
+	GATE(CLK_ACLK_PPMU_DREX0_0, "aclk_ppmu_drex0_0", "dout_aclk_cdrex1",
+			GATE_BUS_CDREX1, 15, CLK_IGNORE_UNUSED, 0),
+	GATE(CLK_ACLK_PPMU_DREX0_1, "aclk_ppmu_drex0_1", "dout_aclk_cdrex1",
+			GATE_BUS_CDREX1, 14, CLK_IGNORE_UNUSED, 0),
+	GATE(CLK_ACLK_PPMU_DREX1_0, "aclk_ppmu_drex1_0", "dout_aclk_cdrex1",
+			GATE_BUS_CDREX1, 13, CLK_IGNORE_UNUSED, 0),
+	GATE(CLK_ACLK_PPMU_DREX1_1, "aclk_ppmu_drex1_1", "dout_aclk_cdrex1",
+			GATE_BUS_CDREX1, 12, CLK_IGNORE_UNUSED, 0),
+
+	GATE(CLK_PCLK_PPMU_DREX0_0, "pclk_ppmu_drex0_0", "dout_pclk_cdrex",
+			GATE_BUS_CDREX1, 29, CLK_IGNORE_UNUSED, 0),
+	GATE(CLK_PCLK_PPMU_DREX0_1, "pclk_ppmu_drex0_1", "dout_pclk_cdrex",
+			GATE_BUS_CDREX1, 28, CLK_IGNORE_UNUSED, 0),
+	GATE(CLK_PCLK_PPMU_DREX1_0, "pclk_ppmu_drex1_0", "dout_pclk_cdrex",
+			GATE_BUS_CDREX1, 27, CLK_IGNORE_UNUSED, 0),
+	GATE(CLK_PCLK_PPMU_DREX1_1, "pclk_ppmu_drex1_1", "dout_pclk_cdrex",
+			GATE_BUS_CDREX1, 26, CLK_IGNORE_UNUSED, 0),
 };
 
 static const struct samsung_div_clock exynos5x_disp_div_clks[] __initconst = {
-- 
2.7.4


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Re: [PATCH v4 2/8] clk: samsung: add new clocks for DMC for Exynos5422 SoC

[Chanwoo Choi]

Hi Lukasz,

I recommend that please don't send the version up patchset before
finishing the discussion.

2019년 2월 2일 (토) 오전 2:47, Lukasz Luba <l.luba@partner.samsung.com>님이 작성:
>
> This patch provides support for clocks needed for Dynamic Memory Controller
> in Exynos5422 SoC. It adds CDREX base register addresses, new DIV, MUX and
> GATE entries.
>
> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
> ---
>  drivers/clk/samsung/clk-exynos5420.c | 46 ++++++++++++++++++++++++++++++++----
>  1 file changed, 42 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/clk/samsung/clk-exynos5420.c b/drivers/clk/samsung/clk-exynos5420.c
> index 34cce3c..f1a4f56 100644
> --- a/drivers/clk/samsung/clk-exynos5420.c
> +++ b/drivers/clk/samsung/clk-exynos5420.c
> @@ -132,6 +132,8 @@
>  #define BPLL_LOCK              0x20010
>  #define BPLL_CON0              0x20110
>  #define SRC_CDREX              0x20200
> +#define GATE_BUS_CDREX0                0x20700
> +#define GATE_BUS_CDREX1                0x20704
>  #define DIV_CDREX0             0x20500
>  #define DIV_CDREX1             0x20504
>  #define KPLL_LOCK              0x28000
> @@ -248,6 +250,8 @@ static const unsigned long exynos5x_clk_regs[] __initconst = {
>         DIV_CDREX1,
>         SRC_KFC,
>         DIV_KFC0,
> +       GATE_BUS_CDREX0,
> +       GATE_BUS_CDREX1,
>  };
>
>  static const unsigned long exynos5800_clk_regs[] __initconst = {
> @@ -425,6 +429,10 @@ PNAME(mout_group13_5800_p) = { "dout_osc_div", "mout_sw_aclkfl1_550_cam" };
>  PNAME(mout_group14_5800_p)     = { "dout_aclk550_cam", "dout_sclk_sw" };
>  PNAME(mout_group15_5800_p)     = { "dout_osc_div", "mout_sw_aclk550_cam" };
>  PNAME(mout_group16_5800_p)     = { "dout_osc_div", "mout_mau_epll_clk" };
> +PNAME(mout_mx_mspll_ccore_phy_p) = { "sclk_bpll", "mout_sclk_dpll",
> +                                       "mout_sclk_mpll", "ff_dout_spll2",
> +                                       "mout_sclk_spll", "mout_sclk_epll"};
> +

Remove unneeded extra blank line.

>
>  /* fixed rate clocks generated outside the soc */
>  static struct samsung_fixed_rate_clock
> @@ -450,7 +458,7 @@ static const struct samsung_fixed_factor_clock
>  static const struct samsung_fixed_factor_clock
>                 exynos5800_fixed_factor_clks[] __initconst = {
>         FFACTOR(0, "ff_dout_epll2", "mout_sclk_epll", 1, 2, 0),
> -       FFACTOR(0, "ff_dout_spll2", "mout_sclk_spll", 1, 2, 0),
> +       FFACTOR(CLK_FF_DOUT_SPLL2, "ff_dout_spll2", "mout_sclk_spll", 1, 2, 0),
>  };
>
>  static const struct samsung_mux_clock exynos5800_mux_clks[] __initconst = {
> @@ -472,11 +480,14 @@ static const struct samsung_mux_clock exynos5800_mux_clks[] __initconst = {
>         MUX(0, "mout_aclk300_disp1", mout_group5_5800_p, SRC_TOP2, 24, 2),
>         MUX(0, "mout_aclk300_gscl", mout_group5_5800_p, SRC_TOP2, 28, 2),
>
> +       MUX(CLK_MOUT_MX_MSPLL_CCORE_PHY, "mout_mx_mspll_ccore_phy",
> +               mout_mx_mspll_ccore_phy_p, SRC_TOP7, 0, 3),
> +
>         MUX(CLK_MOUT_MX_MSPLL_CCORE, "mout_mx_mspll_ccore",
> -                       mout_mx_mspll_ccore_p, SRC_TOP7, 16, 2),
> +                       mout_mx_mspll_ccore_p, SRC_TOP7, 16, 3),
>         MUX_F(CLK_MOUT_MAU_EPLL, "mout_mau_epll_clk", mout_mau_epll_clk_5800_p,
>                         SRC_TOP7, 20, 2, CLK_SET_RATE_PARENT, 0),
> -       MUX(0, "sclk_bpll", mout_bpll_p, SRC_TOP7, 24, 1),
> +       MUX(CLK_SCLK_BPLL, "sclk_bpll", mout_bpll_p, SRC_TOP7, 24, 1),
>         MUX(0, "mout_epll2", mout_epll2_5800_p, SRC_TOP7, 28, 1),
>
>         MUX(0, "mout_aclk550_cam", mout_group3_5800_p, SRC_TOP8, 16, 3),
> @@ -648,7 +659,7 @@ static const struct samsung_mux_clock exynos5x_mux_clks[] __initconst = {

The newly added clocks by this patch are supported on all Exynos5420/5422/5800?
I'm not sure because on the patch description, you only mentioned the
Exynos5422 without Exynos5420/Exynos5800.

As for now, I can't check the Exynos TRM because I'm in holiday until
next Wednesday. I will check them with Exynos542-/5422/5800 TRM on
next Thursday.

>
>         MUX(0, "mout_sclk_mpll", mout_mpll_p, SRC_TOP6, 0, 1),
>         MUX(CLK_MOUT_VPLL, "mout_sclk_vpll", mout_vpll_p, SRC_TOP6, 4, 1),
> -       MUX(0, "mout_sclk_spll", mout_spll_p, SRC_TOP6, 8, 1),
> +       MUX(CLK_MOUT_SCLK_SPLL, "mout_sclk_spll", mout_spll_p, SRC_TOP6, 8, 1),
>         MUX(0, "mout_sclk_ipll", mout_ipll_p, SRC_TOP6, 12, 1),
>         MUX(0, "mout_sclk_rpll", mout_rpll_p, SRC_TOP6, 16, 1),
>         MUX_F(CLK_MOUT_EPLL, "mout_sclk_epll", mout_epll_p, SRC_TOP6, 20, 1,
> @@ -817,6 +828,8 @@ static const struct samsung_div_clock exynos5x_div_clks[] __initconst = {
>         DIV(CLK_DOUT_CLK2X_PHY0, "dout_clk2x_phy0", "dout_sclk_cdrex",
>                         DIV_CDREX0, 3, 5),
>
> +       DIV(0, "dout_pclk_drex0", "dout_cclk_drex0", DIV_CDREX0, 28, 3),

Before applied this patch, on line 809, DIV_CDREX0[28:30] was already
defined with "dout_pclk_cdrex" gate clock name. Why do you redefine it
with same register/same bit with the different clock name? The clock
driver have to get only unique clock for the same register/same bit
information.

   808         /* CDREX Block */
   809         DIV(CLK_DOUT_PCLK_CDREX, "dout_pclk_cdrex",
"dout_aclk_cdrex1",
   810                         DIV_CDREX0, 28, 3),

And also, you don't use "dout_pclk_drex0" defined by you for
CLK_ACLK_PPMU_DREX* gate clock on below. Instead, you use the already
defined 'dout_pclk_cdrex' as I commented.

> +
>         DIV(CLK_DOUT_PCLK_CORE_MEM, "dout_pclk_core_mem", "mout_mclk_cdrex",
>                         DIV_CDREX1, 8, 3),
>
> @@ -1170,6 +1183,31 @@ static const struct samsung_gate_clock exynos5x_gate_clks[] __initconst = {
>                         GATE_TOP_SCLK_ISP, 12, CLK_SET_RATE_PARENT, 0),
>
>         GATE(CLK_G3D, "g3d", "mout_user_aclk_g3d", GATE_IP_G3D, 9, 0, 0),
> +

Add the following comment for the readability in order to sustain the
consistency of this driver.
/* CDREX Block */ or /* CDREX */

> +       GATE(CLK_CLKM_PHY0, "clkm_phy0", "dout_sclk_cdrex",
> +                       GATE_BUS_CDREX0, 0, 0, 0),
> +       GATE(CLK_CLKM_PHY1, "clkm_phy1", "dout_sclk_cdrex",
> +                       GATE_BUS_CDREX0, 1, 0, 0),
> +       GATE(0, "mx_mspll_ccore_phy", "mout_mx_mspll_ccore_phy",
> +                       SRC_MASK_TOP7, 0, CLK_IGNORE_UNUSED, 0),
> +
> +       GATE(CLK_ACLK_PPMU_DREX0_0, "aclk_ppmu_drex0_0", "dout_aclk_cdrex1",
> +                       GATE_BUS_CDREX1, 15, CLK_IGNORE_UNUSED, 0),
> +       GATE(CLK_ACLK_PPMU_DREX0_1, "aclk_ppmu_drex0_1", "dout_aclk_cdrex1",
> +                       GATE_BUS_CDREX1, 14, CLK_IGNORE_UNUSED, 0),
> +       GATE(CLK_ACLK_PPMU_DREX1_0, "aclk_ppmu_drex1_0", "dout_aclk_cdrex1",
> +                       GATE_BUS_CDREX1, 13, CLK_IGNORE_UNUSED, 0),
> +       GATE(CLK_ACLK_PPMU_DREX1_1, "aclk_ppmu_drex1_1", "dout_aclk_cdrex1",
> +                       GATE_BUS_CDREX1, 12, CLK_IGNORE_UNUSED, 0),

You better to move the gate clock of GATE_BUS_CDREX[15:12] under the
gate clock of GATE_BUS_CDREX[29:26]
for the decending order because you defined them as the decending order.

> +
> +       GATE(CLK_PCLK_PPMU_DREX0_0, "pclk_ppmu_drex0_0", "dout_pclk_cdrex",
> +                       GATE_BUS_CDREX1, 29, CLK_IGNORE_UNUSED, 0),
> +       GATE(CLK_PCLK_PPMU_DREX0_1, "pclk_ppmu_drex0_1", "dout_pclk_cdrex",
> +                       GATE_BUS_CDREX1, 28, CLK_IGNORE_UNUSED, 0),
> +       GATE(CLK_PCLK_PPMU_DREX1_0, "pclk_ppmu_drex1_0", "dout_pclk_cdrex",
> +                       GATE_BUS_CDREX1, 27, CLK_IGNORE_UNUSED, 0),
> +       GATE(CLK_PCLK_PPMU_DREX1_1, "pclk_ppmu_drex1_1", "dout_pclk_cdrex",
> +                       GATE_BUS_CDREX1, 26, CLK_IGNORE_UNUSED, 0),
>  };
>
>  static const struct samsung_div_clock exynos5x_disp_div_clks[] __initconst = {
> --
> 2.7.4
>


--
Best Regards,
Chanwoo Choi

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Re: [PATCH v4 2/8] clk: samsung: add new clocks for DMC for Exynos5422 SoC

[Lukasz Luba]

Hi Chanwoo,

On 2/3/19 10:56 AM, Chanwoo Choi wrote:
> Hi Lukasz,
> 
> I recommend that please don't send the version up patchset before
> finishing the discussion.
> 
> 2019년 2월 2일 (토) 오전 2:47, Lukasz Luba <l.luba@partner.samsung.com>님이 작성:
>>
>> This patch provides support for clocks needed for Dynamic Memory Controller
>> in Exynos5422 SoC. It adds CDREX base register addresses, new DIV, MUX and
>> GATE entries.
>>
>> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
>> ---
>>   drivers/clk/samsung/clk-exynos5420.c | 46 ++++++++++++++++++++++++++++++++----
>>   1 file changed, 42 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/clk/samsung/clk-exynos5420.c b/drivers/clk/samsung/clk-exynos5420.c
>> index 34cce3c..f1a4f56 100644
>> --- a/drivers/clk/samsung/clk-exynos5420.c
>> +++ b/drivers/clk/samsung/clk-exynos5420.c
>> @@ -132,6 +132,8 @@
>>   #define BPLL_LOCK              0x20010
>>   #define BPLL_CON0              0x20110
>>   #define SRC_CDREX              0x20200
>> +#define GATE_BUS_CDREX0                0x20700
>> +#define GATE_BUS_CDREX1                0x20704
>>   #define DIV_CDREX0             0x20500
>>   #define DIV_CDREX1             0x20504
>>   #define KPLL_LOCK              0x28000
>> @@ -248,6 +250,8 @@ static const unsigned long exynos5x_clk_regs[] __initconst = {
>>          DIV_CDREX1,
>>          SRC_KFC,
>>          DIV_KFC0,
>> +       GATE_BUS_CDREX0,
>> +       GATE_BUS_CDREX1,
>>   };
>>
>>   static const unsigned long exynos5800_clk_regs[] __initconst = {
>> @@ -425,6 +429,10 @@ PNAME(mout_group13_5800_p) = { "dout_osc_div", "mout_sw_aclkfl1_550_cam" };
>>   PNAME(mout_group14_5800_p)     = { "dout_aclk550_cam", "dout_sclk_sw" };
>>   PNAME(mout_group15_5800_p)     = { "dout_osc_div", "mout_sw_aclk550_cam" };
>>   PNAME(mout_group16_5800_p)     = { "dout_osc_div", "mout_mau_epll_clk" };
>> +PNAME(mout_mx_mspll_ccore_phy_p) = { "sclk_bpll", "mout_sclk_dpll",
>> +                                       "mout_sclk_mpll", "ff_dout_spll2",
>> +                                       "mout_sclk_spll", "mout_sclk_epll"};
>> +
> 
> Remove unneeded extra blank line.
OK
> 
>>
>>   /* fixed rate clocks generated outside the soc */
>>   static struct samsung_fixed_rate_clock
>> @@ -450,7 +458,7 @@ static const struct samsung_fixed_factor_clock
>>   static const struct samsung_fixed_factor_clock
>>                  exynos5800_fixed_factor_clks[] __initconst = {
>>          FFACTOR(0, "ff_dout_epll2", "mout_sclk_epll", 1, 2, 0),
>> -       FFACTOR(0, "ff_dout_spll2", "mout_sclk_spll", 1, 2, 0),
>> +       FFACTOR(CLK_FF_DOUT_SPLL2, "ff_dout_spll2", "mout_sclk_spll", 1, 2, 0),
>>   };
>>
>>   static const struct samsung_mux_clock exynos5800_mux_clks[] __initconst = {
>> @@ -472,11 +480,14 @@ static const struct samsung_mux_clock exynos5800_mux_clks[] __initconst = {
>>          MUX(0, "mout_aclk300_disp1", mout_group5_5800_p, SRC_TOP2, 24, 2),
>>          MUX(0, "mout_aclk300_gscl", mout_group5_5800_p, SRC_TOP2, 28, 2),
>>
>> +       MUX(CLK_MOUT_MX_MSPLL_CCORE_PHY, "mout_mx_mspll_ccore_phy",
>> +               mout_mx_mspll_ccore_phy_p, SRC_TOP7, 0, 3),
>> +
>>          MUX(CLK_MOUT_MX_MSPLL_CCORE, "mout_mx_mspll_ccore",
>> -                       mout_mx_mspll_ccore_p, SRC_TOP7, 16, 2),
>> +                       mout_mx_mspll_ccore_p, SRC_TOP7, 16, 3),
>>          MUX_F(CLK_MOUT_MAU_EPLL, "mout_mau_epll_clk", mout_mau_epll_clk_5800_p,
>>                          SRC_TOP7, 20, 2, CLK_SET_RATE_PARENT, 0),
>> -       MUX(0, "sclk_bpll", mout_bpll_p, SRC_TOP7, 24, 1),
>> +       MUX(CLK_SCLK_BPLL, "sclk_bpll", mout_bpll_p, SRC_TOP7, 24, 1),
>>          MUX(0, "mout_epll2", mout_epll2_5800_p, SRC_TOP7, 28, 1),
>>
>>          MUX(0, "mout_aclk550_cam", mout_group3_5800_p, SRC_TOP8, 16, 3),
>> @@ -648,7 +659,7 @@ static const struct samsung_mux_clock exynos5x_mux_clks[] __initconst = {
> 
> The newly added clocks by this patch are supported on all Exynos5420/5422/5800?
The clocks are the same for Exynos5420/5422/5800 DMCs.

> I'm not sure because on the patch description, you only mentioned the
> Exynos5422 without Exynos5420/Exynos5800.
The driver code supports currently only Exynos5422 due to specific
timings inside, but the clocks are for all three Exynos SoCs.
It does not harm the Exynos5420/5800.
> 
> As for now, I can't check the Exynos TRM because I'm in holiday until
> next Wednesday. I will check them with Exynos542-/5422/5800 TRM on
> next Thursday.
OK, please add me to the communication thread with them. We will speed
up the process (I can test something for them if needed).
> 
>>
>>          MUX(0, "mout_sclk_mpll", mout_mpll_p, SRC_TOP6, 0, 1),
>>          MUX(CLK_MOUT_VPLL, "mout_sclk_vpll", mout_vpll_p, SRC_TOP6, 4, 1),
>> -       MUX(0, "mout_sclk_spll", mout_spll_p, SRC_TOP6, 8, 1),
>> +       MUX(CLK_MOUT_SCLK_SPLL, "mout_sclk_spll", mout_spll_p, SRC_TOP6, 8, 1),
>>          MUX(0, "mout_sclk_ipll", mout_ipll_p, SRC_TOP6, 12, 1),
>>          MUX(0, "mout_sclk_rpll", mout_rpll_p, SRC_TOP6, 16, 1),
>>          MUX_F(CLK_MOUT_EPLL, "mout_sclk_epll", mout_epll_p, SRC_TOP6, 20, 1,
>> @@ -817,6 +828,8 @@ static const struct samsung_div_clock exynos5x_div_clks[] __initconst = {
>>          DIV(CLK_DOUT_CLK2X_PHY0, "dout_clk2x_phy0", "dout_sclk_cdrex",
>>                          DIV_CDREX0, 3, 5),
>>
>> +       DIV(0, "dout_pclk_drex0", "dout_cclk_drex0", DIV_CDREX0, 28, 3),
> 
> Before applied this patch, on line 809, DIV_CDREX0[28:30] was already
> defined with "dout_pclk_cdrex" gate clock name.
In my previous email, I have mentioned that the same bits
(8 combinations) are controlling 3 dividers, which re-branch to 3 edges
in the clock tree named:
CLKDIV_PCLK_CDREX, CLKDIV_PCLK_DREX0, CLKDIV_PCLK_DREX1.
It is in the Exynos5422_UM_REV0.10 documentation section:
7.9.6.7 CLK_DIV_CDREX0

They are put into one because there is a need of synchronization between
the BUS and DREXs (two external memory interfaces).
That's why it looks good in the clock information summary when an
SW engineer can see these HW assumptions.

If you disagree and would like to see only minimal clock definition
which makes the HW working, please write it on LKML.
The clock summary would not be reflecting the actual hierarchy and
someone who is looking for a specific clock details will not find it.

  Why do you redefine it
> with same register/same bit with the different clock name?
The clock is added for information purpose. I can remove it if you like,
but then the clock summary would not reflect the actual HW implementation.

> driver have to get only unique clock for the same register/same bit
> information.
True, driver gets the clocks which have exported IDs.
This one has '0' as you can see and is only for the clk_summary
information output.


The purpose of the patch with detailed clock tree related to DMC was
information, not the driver usage. That's why some clocks they did
no have IDs so drivers would not take them (without a hack).

> 
>     808         /* CDREX Block */
>     809         DIV(CLK_DOUT_PCLK_CDREX, "dout_pclk_cdrex",
> "dout_aclk_cdrex1",
>     810                         DIV_CDREX0, 28, 3),
> 
> And also, you don't use "dout_pclk_drex0" defined by you for
> CLK_ACLK_PPMU_DREX* gate clock on below. Instead, you use the already
> defined 'dout_pclk_cdrex' as I commented.
True
> 
>> +
>>          DIV(CLK_DOUT_PCLK_CORE_MEM, "dout_pclk_core_mem", "mout_mclk_cdrex",
>>                          DIV_CDREX1, 8, 3),
>>
>> @@ -1170,6 +1183,31 @@ static const struct samsung_gate_clock exynos5x_gate_clks[] __initconst = {
>>                          GATE_TOP_SCLK_ISP, 12, CLK_SET_RATE_PARENT, 0),
>>
>>          GATE(CLK_G3D, "g3d", "mout_user_aclk_g3d", GATE_IP_G3D, 9, 0, 0),
>> +
> 
> Add the following comment for the readability in order to sustain the
> consistency of this driver.
> /* CDREX Block */ or /* CDREX */
OK
> 
>> +       GATE(CLK_CLKM_PHY0, "clkm_phy0", "dout_sclk_cdrex",
>> +                       GATE_BUS_CDREX0, 0, 0, 0),
>> +       GATE(CLK_CLKM_PHY1, "clkm_phy1", "dout_sclk_cdrex",
>> +                       GATE_BUS_CDREX0, 1, 0, 0),
>> +       GATE(0, "mx_mspll_ccore_phy", "mout_mx_mspll_ccore_phy",
>> +                       SRC_MASK_TOP7, 0, CLK_IGNORE_UNUSED, 0),
>> +
>> +       GATE(CLK_ACLK_PPMU_DREX0_0, "aclk_ppmu_drex0_0", "dout_aclk_cdrex1",
>> +                       GATE_BUS_CDREX1, 15, CLK_IGNORE_UNUSED, 0),
>> +       GATE(CLK_ACLK_PPMU_DREX0_1, "aclk_ppmu_drex0_1", "dout_aclk_cdrex1",
>> +                       GATE_BUS_CDREX1, 14, CLK_IGNORE_UNUSED, 0),
>> +       GATE(CLK_ACLK_PPMU_DREX1_0, "aclk_ppmu_drex1_0", "dout_aclk_cdrex1",
>> +                       GATE_BUS_CDREX1, 13, CLK_IGNORE_UNUSED, 0),
>> +       GATE(CLK_ACLK_PPMU_DREX1_1, "aclk_ppmu_drex1_1", "dout_aclk_cdrex1",
>> +                       GATE_BUS_CDREX1, 12, CLK_IGNORE_UNUSED, 0),
> 
> You better to move the gate clock of GATE_BUS_CDREX[15:12] under the
> gate clock of GATE_BUS_CDREX[29:26]
> for the decending order because you defined them as the decending order.
Make sense, I will change it.

Regards,
Lukasz
> 
>> +
>> +       GATE(CLK_PCLK_PPMU_DREX0_0, "pclk_ppmu_drex0_0", "dout_pclk_cdrex",
>> +                       GATE_BUS_CDREX1, 29, CLK_IGNORE_UNUSED, 0),
>> +       GATE(CLK_PCLK_PPMU_DREX0_1, "pclk_ppmu_drex0_1", "dout_pclk_cdrex",
>> +                       GATE_BUS_CDREX1, 28, CLK_IGNORE_UNUSED, 0),
>> +       GATE(CLK_PCLK_PPMU_DREX1_0, "pclk_ppmu_drex1_0", "dout_pclk_cdrex",
>> +                       GATE_BUS_CDREX1, 27, CLK_IGNORE_UNUSED, 0),
>> +       GATE(CLK_PCLK_PPMU_DREX1_1, "pclk_ppmu_drex1_1", "dout_pclk_cdrex",
>> +                       GATE_BUS_CDREX1, 26, CLK_IGNORE_UNUSED, 0),
>>   };
>>
>>   static const struct samsung_div_clock exynos5x_disp_div_clks[] __initconst = {
>> --
>> 2.7.4
>>
> 
> 
> --
> Best Regards,
> Chanwoo Choi
> 
> 

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Re: [PATCH v4 2/8] clk: samsung: add new clocks for DMC for Exynos5422 SoC

[Chanwoo Choi]

Hi Lukasz,

On 19. 2. 11. 오후 8:11, Lukasz Luba wrote:
> Hi Chanwoo,
> 
> On 2/3/19 10:56 AM, Chanwoo Choi wrote:
>> Hi Lukasz,
>>
>> I recommend that please don't send the version up patchset before
>> finishing the discussion.
>>
>> 2019년 2월 2일 (토) 오전 2:47, Lukasz Luba <l.luba@partner.samsung.com>님이 작성:
>>>
>>> This patch provides support for clocks needed for Dynamic Memory Controller
>>> in Exynos5422 SoC. It adds CDREX base register addresses, new DIV, MUX and
>>> GATE entries.
>>>
>>> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
>>> ---
>>>   drivers/clk/samsung/clk-exynos5420.c | 46 ++++++++++++++++++++++++++++++++----
>>>   1 file changed, 42 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/drivers/clk/samsung/clk-exynos5420.c b/drivers/clk/samsung/clk-exynos5420.c
>>> index 34cce3c..f1a4f56 100644
>>> --- a/drivers/clk/samsung/clk-exynos5420.c
>>> +++ b/drivers/clk/samsung/clk-exynos5420.c
>>> @@ -132,6 +132,8 @@
>>>   #define BPLL_LOCK              0x20010
>>>   #define BPLL_CON0              0x20110
>>>   #define SRC_CDREX              0x20200
>>> +#define GATE_BUS_CDREX0                0x20700
>>> +#define GATE_BUS_CDREX1                0x20704
>>>   #define DIV_CDREX0             0x20500
>>>   #define DIV_CDREX1             0x20504
>>>   #define KPLL_LOCK              0x28000
>>> @@ -248,6 +250,8 @@ static const unsigned long exynos5x_clk_regs[] __initconst = {
>>>          DIV_CDREX1,
>>>          SRC_KFC,
>>>          DIV_KFC0,
>>> +       GATE_BUS_CDREX0,
>>> +       GATE_BUS_CDREX1,
>>>   };
>>>
>>>   static const unsigned long exynos5800_clk_regs[] __initconst = {
>>> @@ -425,6 +429,10 @@ PNAME(mout_group13_5800_p) = { "dout_osc_div", "mout_sw_aclkfl1_550_cam" };
>>>   PNAME(mout_group14_5800_p)     = { "dout_aclk550_cam", "dout_sclk_sw" };
>>>   PNAME(mout_group15_5800_p)     = { "dout_osc_div", "mout_sw_aclk550_cam" };
>>>   PNAME(mout_group16_5800_p)     = { "dout_osc_div", "mout_mau_epll_clk" };
>>> +PNAME(mout_mx_mspll_ccore_phy_p) = { "sclk_bpll", "mout_sclk_dpll",
>>> +                                       "mout_sclk_mpll", "ff_dout_spll2",
>>> +                                       "mout_sclk_spll", "mout_sclk_epll"};
>>> +
>>
>> Remove unneeded extra blank line.
> OK
>>
>>>
>>>   /* fixed rate clocks generated outside the soc */
>>>   static struct samsung_fixed_rate_clock
>>> @@ -450,7 +458,7 @@ static const struct samsung_fixed_factor_clock
>>>   static const struct samsung_fixed_factor_clock
>>>                  exynos5800_fixed_factor_clks[] __initconst = {
>>>          FFACTOR(0, "ff_dout_epll2", "mout_sclk_epll", 1, 2, 0),
>>> -       FFACTOR(0, "ff_dout_spll2", "mout_sclk_spll", 1, 2, 0),
>>> +       FFACTOR(CLK_FF_DOUT_SPLL2, "ff_dout_spll2", "mout_sclk_spll", 1, 2, 0),
>>>   };
>>>
>>>   static const struct samsung_mux_clock exynos5800_mux_clks[] __initconst = {
>>> @@ -472,11 +480,14 @@ static const struct samsung_mux_clock exynos5800_mux_clks[] __initconst = {
>>>          MUX(0, "mout_aclk300_disp1", mout_group5_5800_p, SRC_TOP2, 24, 2),
>>>          MUX(0, "mout_aclk300_gscl", mout_group5_5800_p, SRC_TOP2, 28, 2),
>>>
>>> +       MUX(CLK_MOUT_MX_MSPLL_CCORE_PHY, "mout_mx_mspll_ccore_phy",
>>> +               mout_mx_mspll_ccore_phy_p, SRC_TOP7, 0, 3),
>>> +
>>>          MUX(CLK_MOUT_MX_MSPLL_CCORE, "mout_mx_mspll_ccore",
>>> -                       mout_mx_mspll_ccore_p, SRC_TOP7, 16, 2),
>>> +                       mout_mx_mspll_ccore_p, SRC_TOP7, 16, 3),
>>>          MUX_F(CLK_MOUT_MAU_EPLL, "mout_mau_epll_clk", mout_mau_epll_clk_5800_p,
>>>                          SRC_TOP7, 20, 2, CLK_SET_RATE_PARENT, 0),
>>> -       MUX(0, "sclk_bpll", mout_bpll_p, SRC_TOP7, 24, 1),
>>> +       MUX(CLK_SCLK_BPLL, "sclk_bpll", mout_bpll_p, SRC_TOP7, 24, 1),
>>>          MUX(0, "mout_epll2", mout_epll2_5800_p, SRC_TOP7, 28, 1),
>>>
>>>          MUX(0, "mout_aclk550_cam", mout_group3_5800_p, SRC_TOP8, 16, 3),
>>> @@ -648,7 +659,7 @@ static const struct samsung_mux_clock exynos5x_mux_clks[] __initconst = {
>>
>> The newly added clocks by this patch are supported on all Exynos5420/5422/5800?
> The clocks are the same for Exynos5420/5422/5800 DMCs.
> 
>> I'm not sure because on the patch description, you only mentioned the
>> Exynos5422 without Exynos5420/Exynos5800.
> The driver code supports currently only Exynos5422 due to specific
> timings inside, but the clocks are for all three Exynos SoCs.
> It does not harm the Exynos5420/5800.
>>
>> As for now, I can't check the Exynos TRM because I'm in holiday until
>> next Wednesday. I will check them with Exynos542-/5422/5800 TRM on
>> next Thursday.
> OK, please add me to the communication thread with them. We will speed
> up the process (I can test something for them if needed).
>>
>>>
>>>          MUX(0, "mout_sclk_mpll", mout_mpll_p, SRC_TOP6, 0, 1),
>>>          MUX(CLK_MOUT_VPLL, "mout_sclk_vpll", mout_vpll_p, SRC_TOP6, 4, 1),
>>> -       MUX(0, "mout_sclk_spll", mout_spll_p, SRC_TOP6, 8, 1),
>>> +       MUX(CLK_MOUT_SCLK_SPLL, "mout_sclk_spll", mout_spll_p, SRC_TOP6, 8, 1),
>>>          MUX(0, "mout_sclk_ipll", mout_ipll_p, SRC_TOP6, 12, 1),
>>>          MUX(0, "mout_sclk_rpll", mout_rpll_p, SRC_TOP6, 16, 1),
>>>          MUX_F(CLK_MOUT_EPLL, "mout_sclk_epll", mout_epll_p, SRC_TOP6, 20, 1,
>>> @@ -817,6 +828,8 @@ static const struct samsung_div_clock exynos5x_div_clks[] __initconst = {
>>>          DIV(CLK_DOUT_CLK2X_PHY0, "dout_clk2x_phy0", "dout_sclk_cdrex",
>>>                          DIV_CDREX0, 3, 5),
>>>
>>> +       DIV(0, "dout_pclk_drex0", "dout_cclk_drex0", DIV_CDREX0, 28, 3),
>>
>> Before applied this patch, on line 809, DIV_CDREX0[28:30] was already
>> defined with "dout_pclk_cdrex" gate clock name.
> In my previous email, I have mentioned that the same bits
> (8 combinations) are controlling 3 dividers, which re-branch to 3 edges
> in the clock tree named:
> CLKDIV_PCLK_CDREX, CLKDIV_PCLK_DREX0, CLKDIV_PCLK_DREX1.
> It is in the Exynos5422_UM_REV0.10 documentation section:
> 7.9.6.7 CLK_DIV_CDREX0

It is my missing point. I checked it on Exynos5422 TRM.
I want to develop the clocks according to H/W clock.
Please keep it without removal.

Instead,
It is very strange case. So, you need to add
the detailed comment when defining the multiple clocks
with same register/same bits. Also, in order to reduce
the confusion of this strange case, IMO you better to
define the three clocks at the nearby in this driver.
(CLKDIV_PCLK_CDREX, CLKDIV_PCLK_DREX0, CLKDIV_PCLK_DREX1)
If they are scattered, it is difficult for understanding
why they are developed like this.

> 
> They are put into one because there is a need of synchronization between
> the BUS and DREXs (two external memory interfaces).
> That's why it looks good in the clock information summary when an
> SW engineer can see these HW assumptions.
> 
> If you disagree and would like to see only minimal clock definition
> which makes the HW working, please write it on LKML.
> The clock summary would not be reflecting the actual hierarchy and
> someone who is looking for a specific clock details will not find it.
> 
>   Why do you redefine it
>> with same register/same bit with the different clock name?
> The clock is added for information purpose. I can remove it if you like,
> but then the clock summary would not reflect the actual HW implementation.
> 
>> driver have to get only unique clock for the same register/same bit
>> information.
> True, driver gets the clocks which have exported IDs.
> This one has '0' as you can see and is only for the clk_summary
> information output.
> 
> 
> The purpose of the patch with detailed clock tree related to DMC was
> information, not the driver usage. That's why some clocks they did
> no have IDs so drivers would not take them (without a hack).
> 
>>
>>     808         /* CDREX Block */
>>     809         DIV(CLK_DOUT_PCLK_CDREX, "dout_pclk_cdrex",
>> "dout_aclk_cdrex1",
>>     810                         DIV_CDREX0, 28, 3),
>>
>> And also, you don't use "dout_pclk_drex0" defined by you for
>> CLK_ACLK_PPMU_DREX* gate clock on below. Instead, you use the already
>> defined 'dout_pclk_cdrex' as I commented.
> True
>>
>>> +
>>>          DIV(CLK_DOUT_PCLK_CORE_MEM, "dout_pclk_core_mem", "mout_mclk_cdrex",
>>>                          DIV_CDREX1, 8, 3),
>>>
>>> @@ -1170,6 +1183,31 @@ static const struct samsung_gate_clock exynos5x_gate_clks[] __initconst = {
>>>                          GATE_TOP_SCLK_ISP, 12, CLK_SET_RATE_PARENT, 0),
>>>
>>>          GATE(CLK_G3D, "g3d", "mout_user_aclk_g3d", GATE_IP_G3D, 9, 0, 0),
>>> +
>>
>> Add the following comment for the readability in order to sustain the
>> consistency of this driver.
>> /* CDREX Block */ or /* CDREX */
> OK
>>
>>> +       GATE(CLK_CLKM_PHY0, "clkm_phy0", "dout_sclk_cdrex",
>>> +                       GATE_BUS_CDREX0, 0, 0, 0),
>>> +       GATE(CLK_CLKM_PHY1, "clkm_phy1", "dout_sclk_cdrex",
>>> +                       GATE_BUS_CDREX0, 1, 0, 0),
>>> +       GATE(0, "mx_mspll_ccore_phy", "mout_mx_mspll_ccore_phy",
>>> +                       SRC_MASK_TOP7, 0, CLK_IGNORE_UNUSED, 0),
>>> +
>>> +       GATE(CLK_ACLK_PPMU_DREX0_0, "aclk_ppmu_drex0_0", "dout_aclk_cdrex1",
>>> +                       GATE_BUS_CDREX1, 15, CLK_IGNORE_UNUSED, 0),
>>> +       GATE(CLK_ACLK_PPMU_DREX0_1, "aclk_ppmu_drex0_1", "dout_aclk_cdrex1",
>>> +                       GATE_BUS_CDREX1, 14, CLK_IGNORE_UNUSED, 0),
>>> +       GATE(CLK_ACLK_PPMU_DREX1_0, "aclk_ppmu_drex1_0", "dout_aclk_cdrex1",
>>> +                       GATE_BUS_CDREX1, 13, CLK_IGNORE_UNUSED, 0),
>>> +       GATE(CLK_ACLK_PPMU_DREX1_1, "aclk_ppmu_drex1_1", "dout_aclk_cdrex1",
>>> +                       GATE_BUS_CDREX1, 12, CLK_IGNORE_UNUSED, 0),
>>
>> You better to move the gate clock of GATE_BUS_CDREX[15:12] under the
>> gate clock of GATE_BUS_CDREX[29:26]
>> for the decending order because you defined them as the decending order.
> Make sense, I will change it.
> 
> Regards,
> Lukasz
>>
>>> +
>>> +       GATE(CLK_PCLK_PPMU_DREX0_0, "pclk_ppmu_drex0_0", "dout_pclk_cdrex",
>>> +                       GATE_BUS_CDREX1, 29, CLK_IGNORE_UNUSED, 0),
>>> +       GATE(CLK_PCLK_PPMU_DREX0_1, "pclk_ppmu_drex0_1", "dout_pclk_cdrex",
>>> +                       GATE_BUS_CDREX1, 28, CLK_IGNORE_UNUSED, 0),
>>> +       GATE(CLK_PCLK_PPMU_DREX1_0, "pclk_ppmu_drex1_0", "dout_pclk_cdrex",
>>> +                       GATE_BUS_CDREX1, 27, CLK_IGNORE_UNUSED, 0),
>>> +       GATE(CLK_PCLK_PPMU_DREX1_1, "pclk_ppmu_drex1_1", "dout_pclk_cdrex",
>>> +                       GATE_BUS_CDREX1, 26, CLK_IGNORE_UNUSED, 0),
>>>   };
>>>
>>>   static const struct samsung_div_clock exynos5x_disp_div_clks[] __initconst = {
>>> --
>>> 2.7.4
>>>
>>
>>
>> --
>> Best Regards,
>> Chanwoo Choi
>>
>>
> 
> 


-- 
Best Regards,
Chanwoo Choi
Samsung Electronics

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[PATCH v4 3/8] clk: samsung: add BPLL rate table for Exynos 5422 SoC

[Lukasz Luba]

Add new table rate for BPLL for Exynos5422 SoC supporting Dynamic Memory
Controller frequencies for driver's DRAM timings.

Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
---
 drivers/clk/samsung/clk-exynos5420.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/clk/samsung/clk-exynos5420.c b/drivers/clk/samsung/clk-exynos5420.c
index f1a4f56..1fc5152 100644
--- a/drivers/clk/samsung/clk-exynos5420.c
+++ b/drivers/clk/samsung/clk-exynos5420.c
@@ -1323,6 +1323,17 @@ static const struct samsung_pll_rate_table exynos5420_pll2550x_24mhz_tbl[] __ini
 	PLL_35XX_RATE(24 * MHZ, 200000000,  200, 3, 3),
 };
 
+static const struct samsung_pll_rate_table exynos5422_bpll_rate_table[] = {
+	PLL_35XX_RATE(24 * MHZ, 825000000, 275, 4, 1),
+	PLL_35XX_RATE(24 * MHZ, 728000000, 182, 3, 1),
+	PLL_35XX_RATE(24 * MHZ, 633000000, 211, 4, 1),
+	PLL_35XX_RATE(24 * MHZ, 543000000, 181, 2, 2),
+	PLL_35XX_RATE(24 * MHZ, 413000000, 413, 6, 2),
+	PLL_35XX_RATE(24 * MHZ, 275000000, 275, 3, 3),
+	PLL_35XX_RATE(24 * MHZ, 206000000, 206, 3, 3),
+	PLL_35XX_RATE(24 * MHZ, 165000000, 110, 2, 3),
+};
+
 static const struct samsung_pll_rate_table exynos5420_epll_24mhz_tbl[] = {
 	PLL_36XX_RATE(24 * MHZ, 600000000U, 100, 2, 1, 0),
 	PLL_36XX_RATE(24 * MHZ, 400000000U, 200, 3, 2, 0),
@@ -1465,7 +1476,7 @@ static void __init exynos5x_clk_init(struct device_node *np,
 		exynos5x_plls[apll].rate_table = exynos5420_pll2550x_24mhz_tbl;
 		exynos5x_plls[epll].rate_table = exynos5420_epll_24mhz_tbl;
 		exynos5x_plls[kpll].rate_table = exynos5420_pll2550x_24mhz_tbl;
-		exynos5x_plls[bpll].rate_table = exynos5420_pll2550x_24mhz_tbl;
+		exynos5x_plls[bpll].rate_table = exynos5422_bpll_rate_table;
 	}
 
 	samsung_clk_register_pll(ctx, exynos5x_plls, ARRAY_SIZE(exynos5x_plls),
-- 
2.7.4


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[PATCH v4 4/8] drivers: devfreq: add DMC driver for Exynos5422

[Lukasz Luba]

This patch adds driver for Exynos5422 Dynamic Memory Controller.
The driver provides support for dynamic frequency and voltage scaling for
DMC and DRAM. It supports changing timings of DRAM running with different
frequency.
The patch also contains needed MAINTAINERS file update.

Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
---
 MAINTAINERS                      |    7 +
 drivers/devfreq/Kconfig          |   13 +
 drivers/devfreq/Makefile         |    1 +
 drivers/devfreq/exynos5422-dmc.c | 1274 ++++++++++++++++++++++++++++++++++++++
 4 files changed, 1295 insertions(+)
 create mode 100644 drivers/devfreq/exynos5422-dmc.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 9f64f8d..e81dfbf 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3310,6 +3310,13 @@ S:	Maintained
 F:	drivers/devfreq/exynos-bus.c
 F:	Documentation/devicetree/bindings/devfreq/exynos-bus.txt
 
+DMC FREQUENCY DRIVER FOR SAMSUNG EXYNOS5422
+M:	Lukasz Luba <l.luba@partner.samsung.com>
+L:	linux-pm@vger.kernel.org
+L:	linux-samsung-soc@vger.kernel.org
+S:	Maintained
+F:	drivers/devfreq/exynos5422-dmc.c
+
 BUSLOGIC SCSI DRIVER
 M:	Khalid Aziz <khalid@gonehiking.org>
 L:	linux-scsi@vger.kernel.org
diff --git a/drivers/devfreq/Kconfig b/drivers/devfreq/Kconfig
index 6a172d3..2a876ad 100644
--- a/drivers/devfreq/Kconfig
+++ b/drivers/devfreq/Kconfig
@@ -113,6 +113,19 @@ config ARM_RK3399_DMC_DEVFREQ
           It sets the frequency for the memory controller and reads the usage counts
           from hardware.
 
+config ARM_EXYNOS5422_DMC_DEVFREQ
+	tristate "ARM EXYNOS5422 DMC DEVFREQ Driver"
+	depends on ARCH_EXYNOS || COMPILE_TEST
+	select DEVFREQ_GOV_SIMPLE_ONDEMAND
+	select DEVFREQ_GOV_PASSIVE
+	select PM_DEVFREQ_EVENT
+	select PM_OPP
+	help
+	  This adds DEVFREQ driver for Exynos5422 DMC (Dynamic Memory Controller).
+	  The driver provides support for Dynamic Voltage and Frequency Scaling in
+	  DMC and DRAM. It also supports changing timings of DRAM running with
+	  different frequency.
+
 source "drivers/devfreq/event/Kconfig"
 
 endif # PM_DEVFREQ
diff --git a/drivers/devfreq/Makefile b/drivers/devfreq/Makefile
index 32b8d4d..d011835 100644
--- a/drivers/devfreq/Makefile
+++ b/drivers/devfreq/Makefile
@@ -11,6 +11,7 @@ obj-$(CONFIG_DEVFREQ_GOV_PASSIVE)	+= governor_passive.o
 obj-$(CONFIG_ARM_EXYNOS_BUS_DEVFREQ)	+= exynos-bus.o
 obj-$(CONFIG_ARM_RK3399_DMC_DEVFREQ)	+= rk3399_dmc.o
 obj-$(CONFIG_ARM_TEGRA_DEVFREQ)		+= tegra-devfreq.o
+obj-$(CONFIG_ARM_EXYNOS5422_DMC_DEVFREQ)	+= exynos5422-dmc.o
 
 # DEVFREQ Event Drivers
 obj-$(CONFIG_PM_DEVFREQ_EVENT)		+= event/
diff --git a/drivers/devfreq/exynos5422-dmc.c b/drivers/devfreq/exynos5422-dmc.c
new file mode 100644
index 0000000..8a19281
--- /dev/null
+++ b/drivers/devfreq/exynos5422-dmc.c
@@ -0,0 +1,1274 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2019 Samsung Electronics Co., Ltd.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/devfreq.h>
+#include <linux/devfreq-event.h>
+#include <linux/device.h>
+#include <linux/export.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/pm_opp.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+
+#define DRIVER_DESC "Driver for Exynos5422 Dynamic Memory Controller dynamic frequency and voltage change"
+
+#define EXYNOS5422_REV_0 (0x1)
+#define EXYNOS5422_PROD_REV_MAIN_MASK (0xf0)
+#define EXYNOS5422_PROD_REV_SUB_MASK (0xf)
+
+#define EXYNOS5_DREXI_TIMINGAREF	(0x0030)
+#define EXYNOS5_DREXI_TIMINGROW0	(0x0034)
+#define EXYNOS5_DREXI_TIMINGDATA0	(0x0038)
+#define EXYNOS5_DREXI_TIMINGPOWER0	(0x003C)
+#define EXYNOS5_DREXI_TIMINGROW1	(0x00E4)
+#define EXYNOS5_DREXI_TIMINGDATA1	(0x00E8)
+#define EXYNOS5_DREXI_TIMINGPOWER1	(0x00EC)
+
+#define EXYNOS5_DREXI_MEMCTRL		(0x0004)
+#define EXYNOS5_DREXI_DIRECTCMD		(0x0010)
+#define EXYNOS5_DREXI_TIMINGAREF	(0x0030)
+#define EXYNOS5_DREXI_TIMINGSETSW	(0x00E0)
+#define EXYNOS5_DREXI_MRSTATUS		(0x0054)
+#define EXYNOS5_DREXI_QOSCONTROL8	(0x00A0)
+#define EXYNOS5_DREXI_BRBRSVCONTROL	(0x0100)
+#define EXYNOS5_DREXI_BP_CONTROL0	(0x0210)
+#define EXYNOS5_DREXI_BP_CONTROL1	(0x0220)
+#define EXYNOS5_DREXI_BP_CONTROL2	(0x0230)
+#define EXYNOS5_DREXI_BP_CONTROL3	(0x0240)
+
+#define EXYNOS5_LPDDR3PHY_CON3                  (0x0A20)
+#define EXYNOS5_TIMING_SET_SWI                  (1UL << 28)
+
+#define AREF_NORMAL			(0x2e)
+
+#define EXYNOS5_TIMING_USE_SET               (1UL << 4)
+#define EXYNOS5_TIMING_SET_SW_CON               (1UL)
+
+#define EXYNOS5_CLK_MUX_STAT_CDREX		(0x400)
+#define EXYNOS5_MCLK_CDREX_SEL_BPLL		(1UL)
+#define EXYNOS5_MCLK_CDREX_SEL_MX_MSPLL		(2UL)
+#define EXYNOS5_CLKSRC_CDREX_SEL_SHIFT		(4)
+#define EXYNOS5_MCLK_CDREX_MASK			(0x7)
+
+#define EXYNOS5_CLK_SRC_CDREX		(0x200)
+#define DMC_PAUSE_CTRL			(0x91C)
+#define DMC_PAUSE_ENABLE			(1UL)
+#define SELF_REFRESH_MASK		(0x20UL)
+#define SR_CMD_EXIT_CHIP0		(0x08000000)
+#define SR_CMD_EXIT_CHIP1		(0x08100000)
+#define CMD_SR_ENTER		(0x04000000)
+#define CMD_SR_EXIT		(0x08000000)
+#define CMD_CHIP0		(0x00000000)
+#define CMD_CHIP1		(0x00100000)
+#define USE_MX_MSPLL_TIMINGS	(1)
+#define USE_BPLL_TIMINGS	(0)
+
+#define DMC_REG_VOLT_STEP	0
+
+#define IS_MEM_2GB(val) \
+	(						\
+	 (((val) & 0xf0) & 0x20) ? 1 :			\
+		(((val) & 0xf0) & 0x30) ? 1 : 0		\
+	)
+
+#define EXYNOS5_POP_OPTIONS(val) \
+		(((val >> 4) & 0x3UL) << 4)
+#define EXYNOS5_DDR_TYPE(val) \
+		(((val >> 14) & 0x1UL))
+
+#define CHIP_PROD_ID	(0)
+#define CHIP_PKG_ID	(4)
+
+#define PMCNT_CONST_RATIO_MUL 15
+#define PMCNT_CONST_RATIO_DIV 10
+
+/**
+ * enum dmc_slot_id - An enum with slots in DMC
+ */
+enum dmc_slot_id {
+	DMC0_0,
+	DMC0_1,
+	DMC1_0,
+	DMC1_1,
+	DMC_SLOTS_END
+};
+
+/**
+ * struct dmc_slot_info - Describes DMC's slot
+ *
+ * The structure holds DMC's slot name which is part of the device name
+ * provided in DT. Each slot has particular share of the DMC bandwidth.
+ * To abstract the model performance and values in performance counters,
+ * fields 'ratio_mul' and 'ratio_div' are used in calculation algorithm
+ * for each slot. Please check the corresponding function with the algorithm,
+ * to see how these variables are used.
+ */
+struct dmc_slot_info {
+	char *name;
+	int id;
+	int ratio_mul;
+	int ratio_div;
+};
+
+/**
+ * struct dmc_opp_table - Operating level desciption
+ *
+ * Covers frequency and voltage settings of the DMC operating mode.
+ */
+struct dmc_opp_table {
+	unsigned long freq_khz;
+	unsigned long volt_uv;
+};
+
+/**
+ * struct dram_param - Parameters for the external memory chip
+ *
+ * Covers timings settings for a particular memory chip's operating frequency.
+ */
+struct dram_param {
+	unsigned int timing_row;
+	unsigned int timing_data;
+	unsigned int timing_power;
+};
+
+/**
+ * struct exynos5_dmc - main structure describing DMC device
+ *
+ * The main structure for the Dynamic Memory Controller which covers clocks,
+ * memory regions, HW information, parameters and current operating mode.
+ */
+struct exynos5_dmc {
+	struct device *dev;
+	struct devfreq *df;
+	struct devfreq_simple_ondemand_data gov_data;
+	void __iomem *base_drexi0;
+	void __iomem *base_drexi1;
+	void __iomem *base_clk;
+	void __iomem *chip_id;
+	struct mutex lock;
+	unsigned long curr_rate;
+	unsigned long curr_volt;
+	const struct dmc_opp_table *opp;
+	const struct dmc_opp_table *opp_bypass;
+	int opp_count;
+	const struct dram_param *dram_param;
+	const struct dram_param *dram_bypass_param;
+	int dram_param_count;
+	unsigned int prod_rev;
+	unsigned int pkg_rev;
+	unsigned int mem_info;
+	struct regulator *vdd_mif;
+	struct clk *fout_spll;
+	struct clk *fout_bpll;
+	struct clk *mout_spll;
+	struct clk *mout_bpll;
+	struct clk *mout_mclk_cdrex;
+	struct clk *dout_clk2x_phy0;
+	struct clk *mout_mx_mspll_ccore;
+	struct clk *mx_mspll_ccore_phy;
+	struct clk *mout_mx_mspll_ccore_phy;
+	struct devfreq_event_dev **counter;
+	int num_counters;
+	bool counters_enabled;
+};
+
+/**
+ * exynos5_counters_fname() - Macro generating function for event devices
+ * @f:		function name suffix
+ *
+ * Macro which generates needed function for manipulation of event devices.
+ * It aims to avoid code duplication relaying on similar prefix and function
+ * parameters in the devfreq event device framework functions.
+ */
+#define exynos5_counters_fname(f)				\
+static int exynos5_counters_##f(struct exynos5_dmc *dmc)	\
+{								\
+	int i, ret;						\
+								\
+	for (i = 0; i < dmc->num_counters; i++) {		\
+		if (!dmc->counter[i])				\
+			continue;				\
+		ret = devfreq_event_##f(dmc->counter[i]);	\
+		if (ret < 0)					\
+			return ret;				\
+	}							\
+	return 0;						\
+}
+exynos5_counters_fname(set_event);
+exynos5_counters_fname(enable_edev);
+exynos5_counters_fname(disable_edev);
+
+/**
+ * dmc_opp_exynos5422 - Array with frequency and voltage values
+ *
+ * Operating points for  Exynos5422 SoC revisions.
+ * The order and sizeof the array has a meaning and is tightly connected with
+ * DRAM parameters in arrays bellow.
+ */
+static const struct dmc_opp_table dmc_opp_exynos5422[] = {
+	{825000, 1050000},
+	{728000, 1037500},
+	{633000, 1012500},
+	{543000, 937500},
+	{413000, 887500},
+	{275000, 875000},
+	{206000, 875000},
+	{165000, 875000},
+};
+
+/**
+ * dmc_opp_bypass_exynos5422 - frequency and voltage level for temporary mode
+ */
+static const struct dmc_opp_table dmc_opp_bypass_exynos5422 = {400000, 887500};
+
+/**
+ * dram_param_exynos5422 - DRAM timings for particular HW setup
+ *
+ * Operating parameters for DRAM memory running with different clock frequency.
+ * The order is the same as in 'dmc_opp_table' above, the highest frequency
+ * is first.
+ * These settings are needed for proper operation of the DRAM memory with
+ * corresponding frequency. They are calculated for Exynos5422 revision 0
+ * with 2GB LPDDR3 memory chip.
+ */
+static const struct dram_param dram_param_exynos5422[] = {
+	{0x365A9713, 0x4740085E, 0x543A0446},
+	{0x30598651, 0x3730085E, 0x4C330336},
+	{0x2A48758F, 0x3730085E, 0x402D0335},
+	{0x244764CD, 0x3730085E, 0x38270335},
+	{0x1B35538A, 0x2720085E, 0x2C1D0225},
+	{0x12244287, 0x2720085E, 0x1C140225},
+	{0x112331C6, 0x2720085E, 0x180F0225},
+	{0x11223185, 0x2720085E, 0x140C0225},
+};
+
+
+/**
+ * Operating parameters for DRAM memory running on temporary clock 400MHz during
+ * switching frequency on the main clock. This variable provides timings for
+ * Exynos5422 SoC revision 0 and DRAM 2GB chip.
+ */
+static const struct dram_param dram_bypass_param_exynos5422 = {
+	0x365a9713, 0x4740085e, 0x543a0446
+};
+
+/**
+ * dmc_slot - An array which holds DMC's slots information
+ *
+ * The array is used in algorithm calculating slots performance and usage
+ * based on performance counters' values. The values i.e. 15/10=1.5 correspond
+ * to slot share in the DMC channel, which has 2.0 abstract width.
+ */
+static const struct dmc_slot_info dmc_slot[] = {
+	{"dmc0_0", DMC0_0, 15, 10},
+	{"dmc0_1", DMC0_1, 5, 10},
+	{"dmc1_0", DMC1_0, 10, 10},
+	{"dmc1_1", DMC1_0, 10, 10},
+};
+
+/**
+ * find_target_freq_id() - Finds requested frequency in local DMC configuration
+ * @dmc:	device for which the information is checked
+ * @target_rate:	requested frequency in KHz
+ *
+ * Seeks in the local DMC driver structure for the requested frequency value
+ * and returns index or error value.
+ */
+static int find_target_freq_idx(struct exynos5_dmc *dmc,
+				unsigned long target_rate)
+{
+	int i;
+
+	for (i = 0; i < dmc->opp_count; i++)
+		if (dmc->opp[i].freq_khz <= target_rate)
+			return i;
+
+	return -EINVAL;
+}
+
+/**
+ * exynos5_get_chip_info() - Gets chip ID information
+ * @dmc:	device for which the information is checked
+ *
+ * Function wrapper for getting the chip ID information.
+ */
+static void exynos5_get_chip_info(struct exynos5_dmc *dmc)
+{
+	unsigned int val;
+
+	val = readl(dmc->chip_id + CHIP_PROD_ID);
+	dmc->prod_rev = val;
+
+	val = readl(dmc->chip_id + CHIP_PKG_ID);
+	dmc->pkg_rev = val;
+
+	dmc->mem_info = EXYNOS5_POP_OPTIONS(val);
+	dmc->mem_info |= EXYNOS5_DDR_TYPE(val);
+}
+
+/**
+ * exynos5_dmc_pause_on_switching() - Controls a pause feature in DMC
+ * @dmc:	device which is used for changing this feature
+ * @set:	a boolean state passing enable/disable request
+ *
+ * There is a need of pausing DREX DMC when divider or MUX in clock tree
+ * changes its configuration. In such situation access to the memory is blocked
+ * in DMC automatically. This feature is used when clock frequency change
+ * request appears and touches clock tree.
+ */
+static int exynos5_dmc_pause_on_switching(struct exynos5_dmc *dmc, bool set)
+{
+	unsigned int val;
+
+	val = readl(dmc->base_clk + DMC_PAUSE_CTRL);
+	if (set)
+		val |= DMC_PAUSE_ENABLE;
+	else
+		val &= ~DMC_PAUSE_ENABLE;
+	writel(val, dmc->base_clk + DMC_PAUSE_CTRL);
+
+	return 0;
+}
+
+/**
+ * exynos5_dmc_chip_revision_settings() - Chooses proper DMC's configuration
+ * @dmc:	device for which is going to be checked and configured
+ *
+ * Function checks the HW product information in order to choose proper
+ * configuration for DMC frequency, voltage and DRAM timings.
+ */
+static int exynos5_dmc_chip_revision_settings(struct exynos5_dmc *dmc)
+{
+	exynos5_get_chip_info(dmc);
+
+	if (!IS_MEM_2GB(dmc->mem_info)) {
+		dev_warn(dmc->dev, "DRAM memory type not supported\n");
+		return -EINVAL;
+	}
+
+	dmc->dram_param = dram_param_exynos5422;
+
+	dmc->dram_param_count = ARRAY_SIZE(dram_param_exynos5422);
+
+	dmc->dram_bypass_param = &dram_bypass_param_exynos5422;
+
+	dmc->opp = dmc_opp_exynos5422;
+	dmc->opp_count = ARRAY_SIZE(dmc_opp_exynos5422);
+
+	dmc->opp_bypass = &dmc_opp_bypass_exynos5422;
+
+	return 0;
+}
+
+/**
+ * exynos5_init_freq_table() - Initialized PM OPP framework
+ * @dev:	devfreq device for which the OPP table is going to be
+ *		initialized
+ * @dmc:	DMC device for which the frequencies are used for OPP init
+ * @profile:	devfreq device's profile
+ *
+ * Populate the devfreq device's OPP table based on current frequency, voltage.
+ */
+static int exynos5_init_freq_table(struct device *dev, struct exynos5_dmc *dmc,
+				   struct devfreq_dev_profile *profile)
+{
+	int i, ret;
+
+	for (i = 0; i < dmc->opp_count; i++) {
+		ret = dev_pm_opp_add(dev, dmc->opp[i].freq_khz,
+				     dmc->opp[i].volt_uv);
+		if (ret) {
+			dev_warn(dev, "failed to add opp %uHz %umV\n", 1, 1);
+			while (i-- > 0)
+				dev_pm_opp_remove(dev, dmc->opp[i].freq_khz);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+/**
+ * exynos5_set_bypass_dram_timings() - Low-level changes of the DRAM timings
+ * @dmc:	device for which the new settings is going to be applied
+ * @param:	DRAM parameters which passes timing data
+ *
+ * Low-level function for changing timings for DRAM memory clocking from
+ * 'bypass' clock source (fixed frequency @400MHz).
+ * It uses timing bank registers set 1.
+ */
+static void exynos5_set_bypass_dram_timings(struct exynos5_dmc *dmc,
+					    const struct dram_param *param)
+{
+
+	writel(AREF_NORMAL, dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGAREF);
+
+	writel(param->timing_row,
+	       dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGROW1);
+	writel(param->timing_row,
+	       dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGROW1);
+	writel(param->timing_data,
+	       dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGDATA1);
+	writel(param->timing_data,
+	       dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGDATA1);
+	writel(param->timing_power,
+	       dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGPOWER1);
+	writel(param->timing_power,
+	       dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGPOWER1);
+}
+
+
+/**
+ * exynos5_dram_change_timings() - Low-level changes of the DRAM final timings
+ * @dmc:	device for which the new settings is going to be applied
+ * @target_rate:	target frequency of the DMC
+ *
+ * Low-level function for changing timings for DRAM memory operating from main
+ * clock source (BPLL), which can have different frequencies. Thus, each
+ * frequency must have corresponding timings register values in order to keep
+ * the needed delays.
+ * It uses timing bank registers set 0.
+ */
+static int exynos5_dram_change_timings(struct exynos5_dmc *dmc,
+				       unsigned long target_rate)
+{
+	int idx;
+
+
+	for (idx = 0; idx < dmc->dram_param_count; idx++)
+		if (dmc->opp[idx].freq_khz <= target_rate)
+			break;
+
+	if (idx >= dmc->dram_param_count)
+		return -EINVAL;
+
+	writel(AREF_NORMAL, dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGAREF);
+
+	writel(dmc->dram_param[idx].timing_row,
+	       dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGROW0);
+	writel(dmc->dram_param[idx].timing_row,
+	       dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGROW0);
+	writel(dmc->dram_param[idx].timing_data,
+	       dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGDATA0);
+	writel(dmc->dram_param[idx].timing_data,
+	       dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGDATA0);
+	writel(dmc->dram_param[idx].timing_power,
+	       dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGPOWER0);
+	writel(dmc->dram_param[idx].timing_power,
+	       dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGPOWER0);
+
+	return 0;
+}
+
+/**
+ * exynos5_switch_timing_regs() - Changes bank register set for DRAM timings
+ * @dmc:	device for which the new settings is going to be applied
+ * @set:	boolean variable passing set value
+ *
+ * Changes the register set, which holds timing parameters.
+ * There is two register sets: 0 and 1. The register set 0
+ * is used in normal operation when the clock is provided from main PLL.
+ * The bank register set 1 is used when the main PLL frequency is going to be
+ * changed and the clock is taken from alternative, stable source.
+ * This function switches between these banks according to the
+ * currently used clock source.
+ */
+static void exynos5_switch_timing_regs(struct exynos5_dmc *dmc, bool set)
+{
+	unsigned int reg;
+
+	reg = readl(dmc->base_clk + EXYNOS5_LPDDR3PHY_CON3);
+
+	if (set)
+		reg |= EXYNOS5_TIMING_SET_SWI;
+	else
+		reg &= ~EXYNOS5_TIMING_SET_SWI;
+
+	writel(reg, dmc->base_clk + EXYNOS5_LPDDR3PHY_CON3);
+}
+
+/*
+ * Change clock parent for MUX_CORE_SEL and the main clock for DMC.
+ * The mux takes two clock sources: main BPLL and mx_mspll ('bypass').
+ */
+static int exynos5_dmc_change_clock_parent(struct exynos5_dmc *dmc,
+					   struct clk *parent,
+					   unsigned int parent_selection_id)
+{
+	unsigned int reg = 0;
+
+	reg = readl(dmc->base_clk + EXYNOS5_CLK_SRC_CDREX);
+	if (clk_set_parent(dmc->mout_mclk_cdrex, parent)) {
+		dev_err(dmc->dev, "Couldn't change parent of mclk_cdrex\n");
+		return -EINVAL;
+	}
+
+	for ( ; reg != parent_selection_id; ) {
+		cpu_relax();
+		reg = readl(dmc->base_clk + EXYNOS5_CLK_MUX_STAT_CDREX);
+		reg >>= EXYNOS5_CLKSRC_CDREX_SEL_SHIFT;
+		reg &= EXYNOS5_MCLK_CDREX_MASK;
+	}
+
+	return 0;
+}
+
+
+/**
+ * exynos5_dmc_change_voltage() - Changes the voltage regulator value
+ * @dmc:	device for which it is going to be set
+ * @target_volt:	new voltage which is chosen to be final
+ *
+ * Main function for changing voltage on the VDD_MIF regulator.
+ */
+static int exynos5_dmc_change_voltage(struct exynos5_dmc *dmc,
+				      unsigned long target_volt)
+{
+	int ret;
+
+	ret = regulator_set_voltage(dmc->vdd_mif, target_volt,
+				    target_volt + DMC_REG_VOLT_STEP);
+
+	if (ret)
+		return ret;
+
+	dmc->curr_volt = target_volt;
+
+	return 0;
+}
+
+/**
+ * exynos5_dmc_align_target_voltage() - Sets the final voltage for the DMC
+ * @dmc:	device for which it is going to be set
+ * @target_volt:	new voltage which is chosen to be final
+ *
+ * Function tries to align voltage to the safe level for 'normal' mode.
+ * It checks the need of higher voltage and changes the value. The target
+ * voltage might be lower that currently set and still the system will be
+ * stable.
+ */
+static int exynos5_dmc_align_target_voltage(struct exynos5_dmc *dmc,
+					    unsigned long target_volt)
+{
+	int ret = 0;
+
+	if (dmc->curr_volt > target_volt)
+		ret = exynos5_dmc_change_voltage(dmc, target_volt);
+
+	return ret;
+}
+
+/**
+ * exynos5_dmc_align_bypass_voltage() - Sets the voltage for the DMC
+ * @dmc:	device for which it is going to be set
+ * @target_volt:	new voltage which is chosen to be final
+ *
+ * Function tries to align voltage to the safe level for the 'bypass' mode.
+ * It checks the need of higher voltage and changes the value.
+ * The target voltage must not be less than currently needed, because
+ * for current frequency the device might become unstable.
+ */
+static int exynos5_dmc_align_bypass_voltage(struct exynos5_dmc *dmc,
+					    unsigned long target_volt)
+{
+	int ret = 0;
+	unsigned long bypass_volt = dmc->opp_bypass->volt_uv;
+
+	target_volt = max(bypass_volt, target_volt);
+
+	if (dmc->curr_volt >= target_volt)
+		return 0;
+
+	ret = exynos5_dmc_change_voltage(dmc, target_volt);
+
+	return ret;
+}
+
+/**
+ * exynos5_dmc_align_bypass_dram_timings() - Chooses and sets DRAM timings
+ * @dmc:	device for which it is going to be set
+ * @target_rate:	new frequency which is chosen to be final
+ *
+ * Function changes the DRAM timings for the temporary 'bypass' mode.
+ */
+static int exynos5_dmc_align_bypass_dram_timings(struct exynos5_dmc *dmc,
+						 unsigned long target_rate)
+{
+	int idx = find_target_freq_idx(dmc, target_rate);
+
+	if (idx < 0)
+		return -EINVAL;
+
+	exynos5_set_bypass_dram_timings(dmc, dmc->dram_bypass_param);
+
+	return 0;
+}
+
+/**
+ * exynos5_dmc_switch_to_bypass_configuration() - Switching to temporary clock
+ * @dmc:	DMC device for which the switching is going to happen
+ * @target_rate:	new frequency which is going to be set as a final
+ * @target_volt:	new voltage which is going to be set as a final
+ *
+ * Function configures DMC and clocks for operating in temporary 'bypass' mode.
+ * This mode is used only temporary but if required, changes voltage and timings
+ * for DRAM chips. It switches the main clock to stable clock source for the
+ * period of the main PLL reconfiguration.
+ */
+static int exynos5_dmc_switch_to_bypass_configuration(struct exynos5_dmc *dmc,
+				   unsigned long target_rate,
+				   unsigned long target_volt)
+{
+	int ret;
+
+	/*
+	 * Having higher voltage for a particular frequency does not harm
+	 * the chip. Use it for the temporary frequency change when one
+	 * voltage manipulation might be avoided.
+	 */
+	ret = exynos5_dmc_align_bypass_voltage(dmc, target_volt);
+	if (ret)
+		return ret;
+
+	/*
+	 * Longer delays for DRAM does not cause crash, the opposite does.
+	 */
+	ret = exynos5_dmc_align_bypass_dram_timings(dmc, target_rate);
+	if (ret)
+		return ret;
+
+	/*
+	 * Delays are long enough, so use them for the new coming clock.
+	 */
+	exynos5_switch_timing_regs(dmc, USE_MX_MSPLL_TIMINGS);
+
+	/*
+	 * Voltage is set at least to a level needed for this frequency,
+	 * so switching clock source is safe now.
+	 */
+	clk_prepare_enable(dmc->fout_spll);
+	clk_prepare_enable(dmc->mout_spll);
+	clk_prepare_enable(dmc->mout_mx_mspll_ccore);
+	ret = exynos5_dmc_change_clock_parent(dmc, dmc->mout_mx_mspll_ccore,
+					      EXYNOS5_MCLK_CDREX_SEL_MX_MSPLL);
+	return ret;
+}
+
+/**
+ * exynos5_dmc_change_freq_and_volt() - Changes voltage and frequency of the DMC
+ * using safe procedure
+ * @dmc:	device for which the frequency is going to be changed
+ * @target_rate:	requested new frequency
+ * @target_volt:	requested voltage which corresponds to the new frequency
+ *
+ * The DMC frequency change procedure requires a few steps.
+ * The main requirement is to change the clock source in the clk mux
+ * for the time of main clock PLL locking. The assumption is that the
+ * alternative clock source set as parent is stable.
+ * The second parent's clock frequency is fixed to 400MHz, it is named 'bypass'
+ * clock. This requires alignment in DRAM timing parameters for the new
+ * T-period. There is two bank sets for keeping DRAM
+ * timings: set 0 and set 1. The set 0 is used when main clock source is
+ * chosen. The 2nd set of regs is used for 'bypass' clock. Switching between
+ * the two bank sets is part of the process.
+ * The voltage must also be aligned to the minimum required level. There is
+ * this intermediate step with switching to 'bypass' parent clock source.
+ * if the old voltage is lower, it requires an increase of the voltage level.
+ * The complexity of the voltage manipulation is hidden in low level function.
+ * In this function there is last alignment of the voltage level at the end.
+ */
+static int
+exynos5_dmc_change_freq_and_volt(struct exynos5_dmc *dmc,
+				 unsigned long target_rate,
+				 unsigned long target_volt)
+{
+	int ret;
+
+	ret = exynos5_dmc_switch_to_bypass_configuration(dmc, target_rate,
+							 target_volt);
+	if (ret)
+		return ret;
+
+	/* We are safe to increase the timings for current bypass frequency.
+	 * Thanks to this the settings we be ready for the upcoming clock source
+	 * change.
+	 */
+	exynos5_dram_change_timings(dmc, target_rate);
+
+	clk_set_rate(dmc->fout_bpll, target_rate * 1000);
+
+	exynos5_switch_timing_regs(dmc, USE_BPLL_TIMINGS);
+
+	ret = exynos5_dmc_change_clock_parent(dmc, dmc->mout_bpll,
+					      EXYNOS5_MCLK_CDREX_SEL_BPLL);
+	if (ret)
+		return ret;
+
+	clk_disable_unprepare(dmc->mout_mx_mspll_ccore);
+	clk_disable_unprepare(dmc->mout_spll);
+	clk_disable_unprepare(dmc->fout_spll);
+	/* Make sure if the voltage is not from 'bypass' settings and align to
+	 * the right level for power efficiency.
+	 */
+	ret = exynos5_dmc_align_target_voltage(dmc, target_volt);
+
+	return ret;
+}
+
+/**
+ * exynos5_dmc_get_volt_freq() - Gets the frequency and voltage from the OPP
+ * table.
+ * @dev:	device for which the frequency is going to be changed
+ * @freq:       requested frequency in KHz
+ * @target_rate:	returned frequency which is the same or lower than
+ *			requested
+ * @target_volt:	returned voltage which corresponds to the returned
+ *			frequency
+ *
+ * Function gets requested frequency and checks OPP framework for needed
+ * frequency and voltage. It populates the values 'target_rate' and
+ * 'target_volt' or returns error value when OPP framework fails.
+ */
+static int exynos5_dmc_get_volt_freq(struct device *dev, unsigned long *freq,
+				     unsigned long *target_rate,
+				     unsigned long *target_volt, u32 flags)
+{
+	struct dev_pm_opp *opp;
+
+	opp = devfreq_recommended_opp(dev, freq, flags);
+	if (IS_ERR(opp))
+		return PTR_ERR(opp);
+
+	*target_rate = dev_pm_opp_get_freq(opp);
+	*target_volt = dev_pm_opp_get_voltage(opp);
+	dev_pm_opp_put(opp);
+
+	return 0;
+}
+
+/**
+ * exynos5_dmc_target() - Function responsible for changing frequency of DMC
+ * @dev:	device for which the frequency is going to be changed
+ * @freq:	requested frequency in KHz
+ * @flags:	flags provided for this frequency change request
+ *
+ * An entry function provided to the devfreq framework which provides frequency
+ * change of the DMC. The function gets the possible rate from OPP table based
+ * on requested frequency. It calls the next function responsible for the
+ * frequency and voltage change. In case of failure, does not set 'curr_rate'
+ * and returns error value to the framework.
+ */
+static int exynos5_dmc_target(struct device *dev, unsigned long *freq,
+			      u32 flags)
+{
+	struct exynos5_dmc *dmc = dev_get_drvdata(dev);
+	unsigned long target_rate = 0;
+	unsigned long target_volt = 0;
+	int ret;
+
+	ret = exynos5_dmc_get_volt_freq(dev, freq, &target_rate, &target_volt,
+					flags);
+	if (ret)
+		return ret;
+
+	if (target_rate == dmc->curr_rate)
+		return 0;
+
+	mutex_lock(&dmc->lock);
+
+	ret = exynos5_dmc_change_freq_and_volt(dmc, target_rate, target_volt);
+
+	if (ret) {
+		mutex_unlock(&dmc->lock);
+		return ret;
+	}
+
+	dmc->curr_rate = target_rate;
+
+	mutex_unlock(&dmc->lock);
+	return 0;
+}
+
+/**
+ * exynos5_cnt_name_match() - Tries to match 'edev' with the right device index
+ * @edev:       event device for which the name is going to be matched
+ *
+ * Function matches the name of the 'edev' counter device with known devices
+ * with configured ratios and shares of the DMC channels.
+ * When the name is matched, it returns the index for the proper device.
+ */
+static int exynos5_cnt_name_match(struct devfreq_event_dev *edev)
+{
+	int i;
+	int id = -ENODEV;
+
+	for (i = 0; i < ARRAY_SIZE(dmc_slot); i++) {
+		if (strstr(edev->desc->name, dmc_slot[i].name))
+			return i;
+	}
+
+	return id;
+}
+
+/**
+ * exynos5_cnt_calculate() - Calculates the values of performance counters.
+ * @edev:	event device for which the counter is used for calculation
+ * @cnt:	raw counter value
+ * @cnt_norm:	counter value normalized to DMC performance ratio for a proper
+ *		channel or virtual channel
+ *
+ * Function calculates normalized value for the raw counter. The raw counter
+ * value does not show real channel usage. The DMC splits not equally the
+ * bandwidth for the channels. The function checks the type of the 'edev'
+ * counter and calculates the normalized value based on the 'shares' of the
+ * bandwidth set in the controller.
+ */
+static int exynos5_cnt_calculate(struct devfreq_event_dev *edev,
+				 unsigned long cnt, u64 *cnt_norm)
+{
+	int idx;
+
+	idx = exynos5_cnt_name_match(edev);
+	if (idx < 0)
+		return idx;
+
+	*cnt_norm = cnt;
+
+	if (!(dmc_slot[idx].ratio_mul == dmc_slot[idx].ratio_div)) {
+		*cnt_norm = *cnt_norm * dmc_slot[idx].ratio_mul;
+		*cnt_norm = div_u64(*cnt_norm, dmc_slot[idx].ratio_div);
+	}
+
+	*cnt_norm = *cnt_norm * PMCNT_CONST_RATIO_MUL;
+	*cnt_norm = div_u64(*cnt_norm, PMCNT_CONST_RATIO_DIV);
+
+	return idx;
+}
+
+/**
+ * exynos5_counters_get() - Gets the performance counters values.
+ * @dmc:	device for which the counters are going to be checked
+ * @load_count:	variable which is populated with counter value
+ * @total_count:	variable which is used as 'wall clock' reference
+ *
+ * Function which provides performance counters values. It sums up counters for
+ * two DMC channels. The 'total_count' is used as a reference and max value.
+ * The ratio 'load_count/total_count' shows the busy percentage [0%, 100%].
+ */
+static int exynos5_counters_get(struct exynos5_dmc *dmc,
+				unsigned long *load_count,
+				unsigned long *total_count)
+{
+	unsigned long load_dmc[2] = {0, 0};
+	unsigned long total = 0;
+	u64 load = 0;
+	struct devfreq_event_data event;
+	int ret, i, idx;
+
+	for (i = 0; i < dmc->num_counters; i++) {
+		if (!dmc->counter[i])
+			continue;
+
+		ret = devfreq_event_get_event(dmc->counter[i], &event);
+		if (ret < 0)
+			return ret;
+
+		idx = exynos5_cnt_calculate(dmc->counter[i], event.load_count,
+					    &load);
+		if (idx < 0)
+			continue;
+
+		if (idx == DMC0_0 || idx == DMC0_1)
+			load_dmc[0] += load;
+		else
+			load_dmc[1] += load;
+
+		if (total < event.total_count)
+			total = event.total_count;
+	}
+
+	*load_count = load_dmc[0] + load_dmc[1];
+	*total_count = total;
+
+	return 0;
+}
+
+/**
+ * exynos5_dmc_get_status() - Read current DMC performance statistics.
+ * @dev:	device for which the statistics are requested
+ * @stat:	structure which has statistic fields
+ *
+ * Function reads the DMC performance counters and calculates 'busy_time'
+ * and 'total_time'. To protect from overflow, the values are shifted right
+ * by 10. After read out the counters are setup to count again.
+ */
+static int exynos5_dmc_get_status(struct device *dev,
+				  struct devfreq_dev_status *stat)
+{
+	struct exynos5_dmc *dmc = dev_get_drvdata(dev);
+	unsigned long load, total;
+	int ret;
+	bool cnt_en;
+
+	mutex_lock(&dmc->lock);
+	cnt_en = dmc->counters_enabled;
+	mutex_unlock(&dmc->lock);
+	if (!cnt_en) {
+		dev_warn(dev, "performance counters needed, but not present\n");
+		return -EAGAIN;
+	}
+
+	ret = exynos5_counters_get(dmc, &load, &total);
+	if (ret < 0)
+		return -EINVAL;
+
+	/* To protect from overflow in calculation ratios, divide by 1024 */
+	stat->busy_time = load >> 10;
+	stat->total_time = total >> 10;
+
+	ret = exynos5_counters_set_event(dmc);
+	if (ret < 0) {
+		dev_err(dmc->dev, "could not set event counter\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+/**
+ * exynos5_dmc_get_cur_freq() - Function returns current DMC frequency
+ * @dev:	device for which the framework checks operating frequency
+ * @freq:	returned frequency value
+ *
+ * It returns the currently used frequency of the DMC. The real operating
+ * frequency might be lower when the clock source value could not be divided
+ * to the requested value.
+ */
+static int exynos5_dmc_get_cur_freq(struct device *dev, unsigned long *freq)
+{
+	struct exynos5_dmc *dmc = dev_get_drvdata(dev);
+
+	mutex_lock(&dmc->lock);
+	*freq = dmc->curr_rate;
+	mutex_unlock(&dmc->lock);
+
+	return 0;
+}
+
+/**
+ * exynos5_dmc_df_profile - Devfreq governor's profile structure
+ *
+ * It provides to the devfreq framework needed functions and polling period.
+ */
+static struct devfreq_dev_profile exynos5_dmc_df_profile = {
+	.polling_ms = 500,
+	.target = exynos5_dmc_target,
+	.get_dev_status = exynos5_dmc_get_status,
+	.get_cur_freq = exynos5_dmc_get_cur_freq,
+};
+
+/**
+ * exynos5_dmc_align_initial_frequency() - Align initial frequency value
+ * @dmc:	device for which the frequency is going to be set
+ * @bootloader_init_freq:	initial frequency set by the bootloader in KHz
+ *
+ * The initial bootloader frequency, which is present during boot, might be
+ * different that supported frequency values in the driver. It is possible
+ * due to different PLL settings or used PLL as a source.
+ * This function provides the 'initial_freq' for the devfreq framework
+ * statistics engine which supports only registered values. Thus, some alignment
+ * must be made.
+ */
+unsigned long
+exynos5_dmc_align_init_freq(struct exynos5_dmc *dmc,
+			    unsigned long bootloader_init_freq)
+{
+	unsigned long aligned_freq;
+	int idx;
+
+	idx = find_target_freq_idx(dmc, bootloader_init_freq);
+	if (idx >= 0)
+		aligned_freq = dmc->opp[idx].freq_khz;
+	else
+		aligned_freq = dmc->opp[dmc->opp_count - 1].freq_khz;
+
+	return aligned_freq;
+}
+
+/**
+ * exynos5_dmc_init_clks() - Initialize clocks needed for DMC operation.
+ * @dev:	device for which the clocks are setup
+ * @dmc:	DMC structure containing needed fields
+ *
+ * Get the needed clocks defined in DT device, enable and set the right parents.
+ * Read current frequency and initialize the initial rate for governor.
+ */
+static int exynos5_dmc_init_clks(struct device *dev, struct exynos5_dmc *dmc)
+{
+	int ret;
+	unsigned long target_volt = 0;
+	unsigned long target_rate = 0;
+
+	dmc->fout_spll = devm_clk_get(dev, "fout_spll");
+	if (IS_ERR(dmc->fout_spll))
+		return PTR_ERR(dmc->fout_spll);
+
+	dmc->fout_bpll = devm_clk_get(dev, "fout_bpll");
+	if (IS_ERR(dmc->fout_bpll))
+		return PTR_ERR(dmc->fout_bpll);
+
+	dmc->mout_mclk_cdrex = devm_clk_get(dev, "mout_mclk_cdrex");
+	if (IS_ERR(dmc->mout_mclk_cdrex))
+		return PTR_ERR(dmc->mout_mclk_cdrex);
+
+	dmc->mout_bpll = devm_clk_get(dev, "mout_bpll");
+	if (IS_ERR(dmc->mout_bpll))
+		return PTR_ERR(dmc->mout_bpll);
+
+	dmc->mout_mx_mspll_ccore = devm_clk_get(dev, "mout_mx_mspll_ccore");
+	if (IS_ERR(dmc->mout_mx_mspll_ccore))
+		return PTR_ERR(dmc->mout_mx_mspll_ccore);
+
+	dmc->dout_clk2x_phy0 = devm_clk_get(dev, "dout_clk2x_phy0");
+	if (IS_ERR(dmc->dout_clk2x_phy0))
+		return PTR_ERR(dmc->dout_clk2x_phy0);
+
+	dmc->mout_spll = devm_clk_get(dev, "ff_dout_spll2");
+	if (IS_ERR(dmc->mout_spll))
+		return PTR_ERR(dmc->mout_spll);
+
+	/*
+	 * Convert frequency to KHz values and set it for the governor.
+	 */
+	dmc->curr_rate = clk_get_rate(dmc->mout_mclk_cdrex) / 1000;
+	dmc->curr_rate = exynos5_dmc_align_init_freq(dmc, dmc->curr_rate);
+	exynos5_dmc_df_profile.initial_freq = dmc->curr_rate;
+
+	ret = exynos5_dmc_get_volt_freq(dev, &dmc->curr_rate, &target_rate,
+					&target_volt, 0);
+	if (ret)
+		return ret;
+
+	dmc->curr_volt = target_volt;
+
+	clk_prepare_enable(dmc->mout_spll);
+	clk_set_parent(dmc->mout_mx_mspll_ccore, dmc->mout_spll);
+	clk_prepare_enable(dmc->mout_mx_mspll_ccore);
+
+	clk_prepare_enable(dmc->fout_bpll);
+	clk_prepare_enable(dmc->mout_bpll);
+
+	return 0;
+}
+
+/**
+ * exynos5_performance_counters_init() - Initializes performance DMC's counters
+ * @dmc:	DMC for which it does the setup
+ *
+ * Initialization of performance counters in DMC for estimating usage.
+ * The counter's values are used for calculation of a memory bandwidth and based
+ * on that the governor changes the frequency.
+ * The counters are not used when the governor is GOVERNOR_USERSPACE.
+ */
+static int exynos5_performance_counters_init(struct exynos5_dmc *dmc)
+{
+	int counters_size;
+	int ret, i;
+
+	dmc->num_counters = devfreq_event_get_edev_count(dmc->dev);
+	if (dmc->num_counters < 0) {
+		dev_err(dmc->dev, "could not get devfreq-event counters\n");
+		return dmc->num_counters;
+	}
+
+	counters_size = sizeof(struct devfreq_event_dev) * dmc->num_counters;
+	dmc->counter = devm_kzalloc(dmc->dev, counters_size, GFP_KERNEL);
+	if (!dmc->counter)
+		return -ENOMEM;
+
+	for (i = 0; i < dmc->num_counters; i++) {
+		dmc->counter[i] =
+			devfreq_event_get_edev_by_phandle(dmc->dev, i);
+		if (IS_ERR_OR_NULL(dmc->counter[i]))
+			return -EPROBE_DEFER;
+	}
+
+	ret = exynos5_counters_enable_edev(dmc);
+	if (ret < 0) {
+		dev_err(dmc->dev, "could not enable event counter\n");
+		return ret;
+	}
+
+	ret = exynos5_counters_set_event(dmc);
+	if (ret < 0) {
+		dev_err(dmc->dev, "counld not set event counter\n");
+		return ret;
+	}
+
+	mutex_lock(&dmc->lock);
+	dmc->counters_enabled = true;
+	mutex_unlock(&dmc->lock);
+
+	return 0;
+}
+
+/**
+ * exynos5_dmc_probe() - Probe function for the DMC driver
+ * @pdev:	platform device for which the driver is going to be initialized
+ *
+ * Initialize basic components: clocks, regulators, performance counters, etc.
+ * Read out product version and based on the information setup
+ * internal structures for the controller (frequency and voltage) and for DRAM
+ * memory parameters: timings for each operating frequency.
+ * Register new devfreq device for controlling DVFS of the DMC.
+ */
+static int exynos5_dmc_probe(struct platform_device *pdev)
+{
+	int ret = 0;
+	struct exynos5_dmc *dmc;
+	struct device *dev = &pdev->dev;
+	struct resource *res;
+
+	dmc = devm_kzalloc(dev, sizeof(*dmc), GFP_KERNEL);
+	if (!dmc)
+		return -ENOMEM;
+
+	mutex_init(&dmc->lock);
+
+	dmc->dev = dev;
+	platform_set_drvdata(pdev, dmc);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	dmc->base_drexi0 = devm_ioremap_resource(dev, res);
+	if (IS_ERR(dmc->base_drexi0))
+		return PTR_ERR(dmc->base_drexi0);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	dmc->base_drexi1 = devm_ioremap_resource(dev, res);
+	if (IS_ERR(dmc->base_drexi1))
+		return PTR_ERR(dmc->base_drexi1);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
+	dmc->base_clk = devm_ioremap_resource(dev, res);
+	if (IS_ERR(dmc->base_clk))
+		return PTR_ERR(dmc->base_clk);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 3);
+	dmc->chip_id = devm_ioremap_resource(dev, res);
+	if (IS_ERR(dmc->chip_id))
+		return PTR_ERR(dmc->chip_id);
+
+	ret = exynos5_dmc_chip_revision_settings(dmc);
+	if (ret)
+		return ret;
+
+	ret = exynos5_init_freq_table(dev, dmc, &exynos5_dmc_df_profile);
+	if (ret)
+		return ret;
+
+	dmc->vdd_mif = devm_regulator_get(dev, "vdd_mif");
+	if (IS_ERR(dmc->vdd_mif)) {
+		ret = PTR_ERR(dmc->vdd_mif);
+		dev_warn(dev, "couldn't get regulator\n");
+		goto remove_opp_table;
+	}
+
+	ret = exynos5_dmc_init_clks(dev, dmc);
+	if (ret) {
+		dev_warn(dev, "couldn't initialize clocks\n");
+		goto remove_opp_table;
+	}
+
+	ret = exynos5_dmc_pause_on_switching(dmc, 1);
+	if (ret) {
+		dev_warn(dev, "couldn't setup pause on switching\n");
+		goto remove_clocks;
+	}
+
+	ret = exynos5_performance_counters_init(dmc);
+	if (ret) {
+		dev_warn(dev, "couldn't probe performance counters\n");
+		goto remove_clocks;
+	}
+	/*
+	 * Setup default thresholds for the devfreq governor.
+	 * The values are chosen based on experiments.
+	 */
+	dmc->gov_data.upthreshold = 30;
+	dmc->gov_data.downdifferential = 5;
+
+	dmc->df = devm_devfreq_add_device(dev, &exynos5_dmc_df_profile,
+					  DEVFREQ_GOV_USERSPACE,
+					  &dmc->gov_data);
+
+	if (IS_ERR(dmc->df)) {
+		ret = PTR_ERR(dmc->df);
+		goto err_devfreq_add;
+	}
+
+	dev_info(&pdev->dev, "DMC init for prod_id=0x%08x pkg_id=0x%08x\n",
+		 dmc->prod_rev, dmc->pkg_rev);
+
+	return 0;
+
+err_devfreq_add:
+	exynos5_counters_disable_edev(dmc);
+remove_clocks:
+	clk_disable_unprepare(dmc->mout_mx_mspll_ccore);
+	clk_disable_unprepare(dmc->mout_spll);
+remove_opp_table:
+	while (dmc->opp_count-- > 0)
+		dev_pm_opp_remove(dev, dmc->opp[dmc->opp_count].freq_khz);
+
+	return ret;
+}
+
+/**
+ * exynos5_dmc_remove() - Remove function for the platform device
+ * @pdev:	platform device which is going to be removed
+ *
+ * The function relies on 'devm' framework function which automatically
+ * clean the device's resources. It just calls explicitly disable function for
+ * the performance counters.
+ */
+static int exynos5_dmc_remove(struct platform_device *pdev)
+{
+	struct exynos5_dmc *dmc = dev_get_drvdata(&pdev->dev);
+
+	exynos5_counters_disable_edev(dmc);
+
+	clk_disable_unprepare(dmc->mout_mx_mspll_ccore);
+	clk_disable_unprepare(dmc->mout_spll);
+
+	dev_pm_opp_remove_table(&pdev->dev);
+
+	dev_info(&pdev->dev, "DMC removed\n");
+
+	return 0;
+}
+
+static const struct of_device_id exynos5_dmc_of_match[] = {
+	{ .compatible = "samsung,exynos5422-dmc", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, exynos5_dmc_of_match);
+
+static struct platform_driver exynos5_dmc_platdrv = {
+	.probe	= exynos5_dmc_probe,
+	.remove = exynos5_dmc_remove,
+	.driver = {
+		.name	= "exynos5-dmc",
+		.of_match_table = exynos5_dmc_of_match,
+	},
+};
+module_platform_driver(exynos5_dmc_platdrv);
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Samsung");
-- 
2.7.4


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Re: [PATCH v4 4/8] drivers: devfreq: add DMC driver for Exynos5422

[Chanwoo Choi]

Hi Lukasz,

As I already commented on the other patch,
please don't send next version patchset until finishing the discussion.

2019년 2월 2일 (토) 오전 2:42, Lukasz Luba <l.luba@partner.samsung.com>님이 작성:
>
> This patch adds driver for Exynos5422 Dynamic Memory Controller.
> The driver provides support for dynamic frequency and voltage scaling for
> DMC and DRAM. It supports changing timings of DRAM running with different
> frequency.
> The patch also contains needed MAINTAINERS file update.
>
> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
> ---
>  MAINTAINERS                      |    7 +
>  drivers/devfreq/Kconfig          |   13 +
>  drivers/devfreq/Makefile         |    1 +
>  drivers/devfreq/exynos5422-dmc.c | 1274 ++++++++++++++++++++++++++++++++++++++
>  4 files changed, 1295 insertions(+)
>  create mode 100644 drivers/devfreq/exynos5422-dmc.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 9f64f8d..e81dfbf 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -3310,6 +3310,13 @@ S:       Maintained
>  F:     drivers/devfreq/exynos-bus.c
>  F:     Documentation/devicetree/bindings/devfreq/exynos-bus.txt
>
> +DMC FREQUENCY DRIVER FOR SAMSUNG EXYNOS5422
> +M:     Lukasz Luba <l.luba@partner.samsung.com>
> +L:     linux-pm@vger.kernel.org
> +L:     linux-samsung-soc@vger.kernel.org
> +S:     Maintained
> +F:     drivers/devfreq/exynos5422-dmc.c
> +
>  BUSLOGIC SCSI DRIVER
>  M:     Khalid Aziz <khalid@gonehiking.org>
>  L:     linux-scsi@vger.kernel.org
> diff --git a/drivers/devfreq/Kconfig b/drivers/devfreq/Kconfig
> index 6a172d3..2a876ad 100644
> --- a/drivers/devfreq/Kconfig
> +++ b/drivers/devfreq/Kconfig
> @@ -113,6 +113,19 @@ config ARM_RK3399_DMC_DEVFREQ
>            It sets the frequency for the memory controller and reads the usage counts
>            from hardware.
>
> +config ARM_EXYNOS5422_DMC_DEVFREQ

Move it under ARM_EXYNOS_BUS_DEVFREQ alphabetically.

> +       tristate "ARM EXYNOS5422 DMC DEVFREQ Driver"
> +       depends on ARCH_EXYNOS || COMPILE_TEST
> +       select DEVFREQ_GOV_SIMPLE_ONDEMAND

The exynos5422-dmc.c driver use the 'userspace' governor. Why do you
add the DEVFREQ_GOV_SIMPLE_ONDEMAND dependency instead of
GOV_USERSPACE?

Even if you use userspace governor with devfreq_add_device() you added
the 'struct devfreq_dev_profile' for simple_ondemand governor. Why
don't you use 'simple_ondemand' governor as the default governor?

This patch description doesn't contain the something of
simple_ondemand governor.

> +       select DEVFREQ_GOV_PASSIVE

The exynos5422-dmc.c doesn't use 'passive' governor. Maybe you just
copied from ARM_EXYNOS_BUS_DEVFREQ's config. Remove this dependency.

> +       select PM_DEVFREQ_EVENT
> +       select PM_OPP
> +       help
> +         This adds DEVFREQ driver for Exynos5422 DMC (Dynamic Memory Controller).
> +         The driver provides support for Dynamic Voltage and Frequency Scaling in
> +         DMC and DRAM. It also supports changing timings of DRAM running with
> +         different frequency.
> +
>  source "drivers/devfreq/event/Kconfig"
>
>  endif # PM_DEVFREQ
> diff --git a/drivers/devfreq/Makefile b/drivers/devfreq/Makefile
> index 32b8d4d..d011835 100644
> --- a/drivers/devfreq/Makefile
> +++ b/drivers/devfreq/Makefile
> @@ -11,6 +11,7 @@ obj-$(CONFIG_DEVFREQ_GOV_PASSIVE)     += governor_passive.o
>  obj-$(CONFIG_ARM_EXYNOS_BUS_DEVFREQ)   += exynos-bus.o
>  obj-$(CONFIG_ARM_RK3399_DMC_DEVFREQ)   += rk3399_dmc.o
>  obj-$(CONFIG_ARM_TEGRA_DEVFREQ)                += tegra-devfreq.o
> +obj-$(CONFIG_ARM_EXYNOS5422_DMC_DEVFREQ)       += exynos5422-dmc.o

Move it under CONFIG_ARM_EXYNOS_BUS_DEVFREQ alphabetically.

>
>  # DEVFREQ Event Drivers
>  obj-$(CONFIG_PM_DEVFREQ_EVENT)         += event/
> diff --git a/drivers/devfreq/exynos5422-dmc.c b/drivers/devfreq/exynos5422-dmc.c
> new file mode 100644
> index 0000000..8a19281
> --- /dev/null
> +++ b/drivers/devfreq/exynos5422-dmc.c
> @@ -0,0 +1,1274 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (c) 2019 Samsung Electronics Co., Ltd.
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/devfreq.h>
> +#include <linux/devfreq-event.h>
> +#include <linux/device.h>
> +#include <linux/export.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/of_device.h>
> +#include <linux/pm_opp.h>
> +#include <linux/platform_device.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/slab.h>
> +
> +#define DRIVER_DESC "Driver for Exynos5422 Dynamic Memory Controller dynamic frequency and voltage change"

Don't need to define the separate constant because MODULE_DESCRIPTION
only use it. You can describe it with MODULE_DESCRIPTION. Remove the
separate definition.

> +
> +#define EXYNOS5422_REV_0 (0x1)
> +#define EXYNOS5422_PROD_REV_MAIN_MASK (0xf0)
> +#define EXYNOS5422_PROD_REV_SUB_MASK (0xf)

The above three definitions are never used on this driver.

> +
> +#define EXYNOS5_DREXI_TIMINGAREF       (0x0030)
> +#define EXYNOS5_DREXI_TIMINGROW0       (0x0034)
> +#define EXYNOS5_DREXI_TIMINGDATA0      (0x0038)
> +#define EXYNOS5_DREXI_TIMINGPOWER0     (0x003C)
> +#define EXYNOS5_DREXI_TIMINGROW1       (0x00E4)
> +#define EXYNOS5_DREXI_TIMINGDATA1      (0x00E8)
> +#define EXYNOS5_DREXI_TIMINGPOWER1     (0x00EC)
> +
> +#define EXYNOS5_DREXI_MEMCTRL          (0x0004)
> +#define EXYNOS5_DREXI_DIRECTCMD                (0x0010)
> +#define EXYNOS5_DREXI_TIMINGAREF       (0x0030)

It is redefined on this driver.

> +#define EXYNOS5_DREXI_TIMINGSETSW      (0x00E0)
> +#define EXYNOS5_DREXI_MRSTATUS         (0x0054)
> +#define EXYNOS5_DREXI_QOSCONTROL8      (0x00A0)
> +#define EXYNOS5_DREXI_BRBRSVCONTROL    (0x0100)
> +#define EXYNOS5_DREXI_BP_CONTROL0      (0x0210)
> +#define EXYNOS5_DREXI_BP_CONTROL1      (0x0220)
> +#define EXYNOS5_DREXI_BP_CONTROL2      (0x0230)
> +#define EXYNOS5_DREXI_BP_CONTROL3      (0x0240)
> +
> +#define EXYNOS5_LPDDR3PHY_CON3                  (0x0A20)
> +#define EXYNOS5_TIMING_SET_SWI                  (1UL << 28)

Dont' use the space for indentation.

> +
> +#define AREF_NORMAL                    (0x2e)

It doesn't contain the 'EXYNOS_' prefix. why?

> +
> +#define EXYNOS5_TIMING_USE_SET               (1UL << 4)
> +#define EXYNOS5_TIMING_SET_SW_CON               (1UL)

Dont' use the space for indentation.

hmm. The above two definitions are not used on this driver.
Do you just copy them from other file?

> +
> +#define EXYNOS5_CLK_MUX_STAT_CDREX             (0x400)
> +#define EXYNOS5_MCLK_CDREX_SEL_BPLL            (1UL)
> +#define EXYNOS5_MCLK_CDREX_SEL_MX_MSPLL                (2UL)
> +#define EXYNOS5_CLKSRC_CDREX_SEL_SHIFT         (4)
> +#define EXYNOS5_MCLK_CDREX_MASK                        (0x7)
> +
> +#define EXYNOS5_CLK_SRC_CDREX          (0x200)

> +#define DMC_PAUSE_CTRL                 (0x91C)
> +#define DMC_PAUSE_ENABLE                       (1UL)

> +#define SELF_REFRESH_MASK              (0x20UL)
> +#define SR_CMD_EXIT_CHIP0              (0x08000000)
> +#define SR_CMD_EXIT_CHIP1              (0x08100000)
> +#define CMD_SR_ENTER           (0x04000000)
> +#define CMD_SR_EXIT            (0x08000000)
> +#define CMD_CHIP0              (0x00000000)
> +#define CMD_CHIP1              (0x00100000)

The above seven definitions are not used.

> +#define USE_MX_MSPLL_TIMINGS   (1)
> +#define USE_BPLL_TIMINGS       (0)
> +
> +#define DMC_REG_VOLT_STEP      0

Why don't you add 'EXYNOS5_' prefix from 'DMC_PAUSE_CTRL' to 'USE_BPLL_TIMINGS'?

> +
> +#define IS_MEM_2GB(val) \
> +       (                                               \
> +        (((val) & 0xf0) & 0x20) ? 1 :                  \
> +               (((val) & 0xf0) & 0x30) ? 1 : 0         \
> +       )
> +
> +#define EXYNOS5_POP_OPTIONS(val) \
> +               (((val >> 4) & 0x3UL) << 4)

Don't need to add on next line. It is possible to specify on per line.

> +#define EXYNOS5_DDR_TYPE(val) \
> +               (((val >> 14) & 0x1UL))

ditto.

> +
> +#define CHIP_PROD_ID   (0)
> +#define CHIP_PKG_ID    (4)
> +
> +#define PMCNT_CONST_RATIO_MUL 15
> +#define PMCNT_CONST_RATIO_DIV 10

It looks like the value for PPMU. You better to add 'PPMU_' prefix.

> +

The above definitions have the different indentation. Please keep the
same indentation for the readability.

> +/**
> + * enum dmc_slot_id - An enum with slots in DMC
> + */
> +enum dmc_slot_id {
> +       DMC0_0,
> +       DMC0_1,
> +       DMC1_0,
> +       DMC1_1,
> +       DMC_SLOTS_END
> +};
> +
> +/**
> + * struct dmc_slot_info - Describes DMC's slot
> + *
> + * The structure holds DMC's slot name which is part of the device name
> + * provided in DT. Each slot has particular share of the DMC bandwidth.
> + * To abstract the model performance and values in performance counters,
> + * fields 'ratio_mul' and 'ratio_div' are used in calculation algorithm
> + * for each slot. Please check the corresponding function with the algorithm,
> + * to see how these variables are used.
> + */
> +struct dmc_slot_info {
> +       char *name;
> +       int id;
> +       int ratio_mul;
> +       int ratio_div;
> +};
> +
> +/**
> + * struct dmc_opp_table - Operating level desciption
> + *
> + * Covers frequency and voltage settings of the DMC operating mode.
> + */
> +struct dmc_opp_table {
> +       unsigned long freq_khz;
> +       unsigned long volt_uv;
> +};
> +
> +/**
> + * struct dram_param - Parameters for the external memory chip
> + *
> + * Covers timings settings for a particular memory chip's operating frequency.
> + */
> +struct dram_param {
> +       unsigned int timing_row;
> +       unsigned int timing_data;
> +       unsigned int timing_power;
> +};
> +
> +/**
> + * struct exynos5_dmc - main structure describing DMC device
> + *
> + * The main structure for the Dynamic Memory Controller which covers clocks,
> + * memory regions, HW information, parameters and current operating mode.
> + */
> +struct exynos5_dmc {
> +       struct device *dev;
> +       struct devfreq *df;
> +       struct devfreq_simple_ondemand_data gov_data;
> +       void __iomem *base_drexi0;
> +       void __iomem *base_drexi1;
> +       void __iomem *base_clk;
> +       void __iomem *chip_id;
> +       struct mutex lock;
> +       unsigned long curr_rate;
> +       unsigned long curr_volt;
> +       const struct dmc_opp_table *opp;
> +       const struct dmc_opp_table *opp_bypass;
> +       int opp_count;
> +       const struct dram_param *dram_param;
> +       const struct dram_param *dram_bypass_param;
> +       int dram_param_count;
> +       unsigned int prod_rev;
> +       unsigned int pkg_rev;
> +       unsigned int mem_info;
> +       struct regulator *vdd_mif;
> +       struct clk *fout_spll;
> +       struct clk *fout_bpll;
> +       struct clk *mout_spll;
> +       struct clk *mout_bpll;
> +       struct clk *mout_mclk_cdrex;
> +       struct clk *dout_clk2x_phy0;
> +       struct clk *mout_mx_mspll_ccore;
> +       struct clk *mx_mspll_ccore_phy;
> +       struct clk *mout_mx_mspll_ccore_phy;
> +       struct devfreq_event_dev **counter;
> +       int num_counters;
> +       bool counters_enabled;
> +};
> +
> +/**
> + * exynos5_counters_fname() - Macro generating function for event devices
> + * @f:         function name suffix
> + *
> + * Macro which generates needed function for manipulation of event devices.
> + * It aims to avoid code duplication relaying on similar prefix and function
> + * parameters in the devfreq event device framework functions.
> + */
> +#define exynos5_counters_fname(f)                              \
> +static int exynos5_counters_##f(struct exynos5_dmc *dmc)       \
> +{                                                              \
> +       int i, ret;                                             \
> +                                                               \
> +       for (i = 0; i < dmc->num_counters; i++) {               \
> +               if (!dmc->counter[i])                           \
> +                       continue;                               \
> +               ret = devfreq_event_##f(dmc->counter[i]);       \
> +               if (ret < 0)                                    \
> +                       return ret;                             \
> +       }                                                       \
> +       return 0;                                               \
> +}
> +exynos5_counters_fname(set_event);
> +exynos5_counters_fname(enable_edev);
> +exynos5_counters_fname(disable_edev);
> +
> +/**
> + * dmc_opp_exynos5422 - Array with frequency and voltage values
> + *
> + * Operating points for  Exynos5422 SoC revisions.
> + * The order and sizeof the array has a meaning and is tightly connected with
> + * DRAM parameters in arrays bellow.
> + */
> +static const struct dmc_opp_table dmc_opp_exynos5422[] = {
> +       {825000, 1050000},
> +       {728000, 1037500},
> +       {633000, 1012500},
> +       {543000, 937500},
> +       {413000, 887500},
> +       {275000, 875000},
> +       {206000, 875000},
> +       {165000, 875000},
> +};

Usually, almost device drivers got the OPP table from devicetree by
using dev_pm_opp_of_add_table(). You can refer to other devfreq device
drivers like exynos-bus.c, rk3399_dmc.c. Please get the opp
information from devicetree.

If define the opp table in the device driver, the user cannot check
the opp information through devicetree.

> +
> +/**
> + * dmc_opp_bypass_exynos5422 - frequency and voltage level for temporary mode
> + */
> +static const struct dmc_opp_table dmc_opp_bypass_exynos5422 = {400000, 887500};

ditto.

> +
> +/**
> + * dram_param_exynos5422 - DRAM timings for particular HW setup
> + *
> + * Operating parameters for DRAM memory running with different clock frequency.
> + * The order is the same as in 'dmc_opp_table' above, the highest frequency
> + * is first.
> + * These settings are needed for proper operation of the DRAM memory with
> + * corresponding frequency. They are calculated for Exynos5422 revision 0
> + * with 2GB LPDDR3 memory chip.
> + */
> +static const struct dram_param dram_param_exynos5422[] = {
> +       {0x365A9713, 0x4740085E, 0x543A0446},
> +       {0x30598651, 0x3730085E, 0x4C330336},
> +       {0x2A48758F, 0x3730085E, 0x402D0335},
> +       {0x244764CD, 0x3730085E, 0x38270335},
> +       {0x1B35538A, 0x2720085E, 0x2C1D0225},
> +       {0x12244287, 0x2720085E, 0x1C140225},
> +       {0x112331C6, 0x2720085E, 0x180F0225},
> +       {0x11223185, 0x2720085E, 0x140C0225},
> +};

If device driver need  data depends on h/w device like opp table, you
shoud get them from devicetree which specify the h/w information. You
can refer to  'drivers/devfreq/rk3399_dmc.c' in order to get timing
information.

> +
> +
> +/**
> + * Operating parameters for DRAM memory running on temporary clock 400MHz during
> + * switching frequency on the main clock. This variable provides timings for
> + * Exynos5422 SoC revision 0 and DRAM 2GB chip.
> + */
> +static const struct dram_param dram_bypass_param_exynos5422 = {
> +       0x365a9713, 0x4740085e, 0x543a0446
> +};

ditto.

> +
> +/**
> + * dmc_slot - An array which holds DMC's slots information
> + *
> + * The array is used in algorithm calculating slots performance and usage
> + * based on performance counters' values. The values i.e. 15/10=1.5 correspond
> + * to slot share in the DMC channel, which has 2.0 abstract width.
> + */
> +static const struct dmc_slot_info dmc_slot[] = {
> +       {"dmc0_0", DMC0_0, 15, 10},
> +       {"dmc0_1", DMC0_1, 5, 10},
> +       {"dmc1_0", DMC1_0, 10, 10},
> +       {"dmc1_1", DMC1_0, 10, 10},
> +};
> +
> +/**
> + * find_target_freq_id() - Finds requested frequency in local DMC configuration
> + * @dmc:       device for which the information is checked
> + * @target_rate:       requested frequency in KHz
> + *
> + * Seeks in the local DMC driver structure for the requested frequency value
> + * and returns index or error value.
> + */
> +static int find_target_freq_idx(struct exynos5_dmc *dmc,
> +                               unsigned long target_rate)
> +{
> +       int i;
> +
> +       for (i = 0; i < dmc->opp_count; i++)
> +               if (dmc->opp[i].freq_khz <= target_rate)
> +                       return i;
> +
> +       return -EINVAL;
> +}
> +
> +/**
> + * exynos5_get_chip_info() - Gets chip ID information
> + * @dmc:       device for which the information is checked
> + *
> + * Function wrapper for getting the chip ID information.
> + */
> +static void exynos5_get_chip_info(struct exynos5_dmc *dmc)
> +{
> +       unsigned int val;
> +
> +       val = readl(dmc->chip_id + CHIP_PROD_ID);
> +       dmc->prod_rev = val;
> +
> +       val = readl(dmc->chip_id + CHIP_PKG_ID);
> +       dmc->pkg_rev = val;
 > +
> +       dmc->mem_info = EXYNOS5_POP_OPTIONS(val);
> +       dmc->mem_info |= EXYNOS5_DDR_TYPE(val);
> +}

Don't need to make it as the separate function. Just add this code in
the exynos5_dmc_chip_revision_settings.

> +
> +/**
> + * exynos5_dmc_pause_on_switching() - Controls a pause feature in DMC
> + * @dmc:       device which is used for changing this feature
> + * @set:       a boolean state passing enable/disable request
> + *
> + * There is a need of pausing DREX DMC when divider or MUX in clock tree
> + * changes its configuration. In such situation access to the memory is blocked
> + * in DMC automatically. This feature is used when clock frequency change
> + * request appears and touches clock tree.
> + */
> +static int exynos5_dmc_pause_on_switching(struct exynos5_dmc *dmc, bool set)

Don't need to make it as the separate function. It is only used on
probe() function.

> +{
> +       unsigned int val;
> +
> +       val = readl(dmc->base_clk + DMC_PAUSE_CTRL);
> +       if (set)
> +               val |= DMC_PAUSE_ENABLE;
> +       else
> +               val &= ~DMC_PAUSE_ENABLE;
> +       writel(val, dmc->base_clk + DMC_PAUSE_CTRL);

The dt-binding file doesn't explain the 'reg' property for 'base_clk'.
You are missing.
When I tried to find what are the base address, it is the register map
of clock-controller.
This driver accesed the register of clock controller without any
functions of CCF
(common clock framework). It is wrong.

If you need to get the some information of clock, must have to use the CCF.

> +
> +       return 0;
> +}


> +
> +/**
> + * exynos5_dmc_chip_revision_settings() - Chooses proper DMC's configuration
> + * @dmc:       device for which is going to be checked and configured
> + *
> + * Function checks the HW product information in order to choose proper
> + * configuration for DMC frequency, voltage and DRAM timings.
> + */
> +static int exynos5_dmc_chip_revision_settings(struct exynos5_dmc *dmc)
> +{
> +       exynos5_get_chip_info(dmc);
> +
> +       if (!IS_MEM_2GB(dmc->mem_info)) {
> +               dev_warn(dmc->dev, "DRAM memory type not supported\n");
> +               return -EINVAL;
> +       }
> +
> +       dmc->dram_param = dram_param_exynos5422;
> +
> +       dmc->dram_param_count = ARRAY_SIZE(dram_param_exynos5422);
> +
> +       dmc->dram_bypass_param = &dram_bypass_param_exynos5422;
> +
> +       dmc->opp = dmc_opp_exynos5422;
> +       dmc->opp_count = ARRAY_SIZE(dmc_opp_exynos5422);
> +
> +       dmc->opp_bypass = &dmc_opp_bypass_exynos5422;

As I already commented, you have to get the data depends on h/w device
from devicetree like opp information.

> +
> +       return 0;
> +}
> +
> +/**
> + * exynos5_init_freq_table() - Initialized PM OPP framework
> + * @dev:       devfreq device for which the OPP table is going to be
> + *             initialized
> + * @dmc:       DMC device for which the frequencies are used for OPP init
> + * @profile:   devfreq device's profile
> + *
> + * Populate the devfreq device's OPP table based on current frequency, voltage.
> + */
> +static int exynos5_init_freq_table(struct device *dev, struct exynos5_dmc *dmc,
> +                                  struct devfreq_dev_profile *profile)
> +{
> +       int i, ret;
> +
> +       for (i = 0; i < dmc->opp_count; i++) {
> +               ret = dev_pm_opp_add(dev, dmc->opp[i].freq_khz,
> +                                    dmc->opp[i].volt_uv);
> +               if (ret) {
> +                       dev_warn(dev, "failed to add opp %uHz %umV\n", 1, 1);
> +                       while (i-- > 0)
> +                               dev_pm_opp_remove(dev, dmc->opp[i].freq_khz);
> +                       return ret;
> +               }
> +       }
> +
> +       return 0;
> +}

If you get the OPP information from devicetree through OPP framework,
you don't need to add them by yourself.

> +
> +/**
> + * exynos5_set_bypass_dram_timings() - Low-level changes of the DRAM timings
> + * @dmc:       device for which the new settings is going to be applied
> + * @param:     DRAM parameters which passes timing data
> + *
> + * Low-level function for changing timings for DRAM memory clocking from
> + * 'bypass' clock source (fixed frequency @400MHz).
> + * It uses timing bank registers set 1.
> + */
> +static void exynos5_set_bypass_dram_timings(struct exynos5_dmc *dmc,
> +                                           const struct dram_param *param)
> +{
> +

Remove unneeded blank line.

> +       writel(AREF_NORMAL, dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGAREF);
> +
> +       writel(param->timing_row,
> +              dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGROW1);
> +       writel(param->timing_row,
> +              dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGROW1);
> +       writel(param->timing_data,
> +              dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGDATA1);
> +       writel(param->timing_data,
> +              dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGDATA1);
> +       writel(param->timing_power,
> +              dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGPOWER1);
> +       writel(param->timing_power,
> +              dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGPOWER1);
> +}
> +

Remove unneeded blank line.

> +
> +/**
> + * exynos5_dram_change_timings() - Low-level changes of the DRAM final timings
> + * @dmc:       device for which the new settings is going to be applied
> + * @target_rate:       target frequency of the DMC
> + *
> + * Low-level function for changing timings for DRAM memory operating from main
> + * clock source (BPLL), which can have different frequencies. Thus, each
> + * frequency must have corresponding timings register values in order to keep
> + * the needed delays.
> + * It uses timing bank registers set 0.
> + */
> +static int exynos5_dram_change_timings(struct exynos5_dmc *dmc,
> +                                      unsigned long target_rate)
> +{
> +       int idx;
> +
> +

Remove unneeded blank line.

> +       for (idx = 0; idx < dmc->dram_param_count; idx++)
> +               if (dmc->opp[idx].freq_khz <= target_rate)
> +                       break;
> +
> +       if (idx >= dmc->dram_param_count)
> +               return -EINVAL;
> +
> +       writel(AREF_NORMAL, dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGAREF);
> +
> +       writel(dmc->dram_param[idx].timing_row,
> +              dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGROW0);
> +       writel(dmc->dram_param[idx].timing_row,
> +              dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGROW0);
> +       writel(dmc->dram_param[idx].timing_data,
> +              dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGDATA0);
> +       writel(dmc->dram_param[idx].timing_data,
> +              dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGDATA0);
> +       writel(dmc->dram_param[idx].timing_power,
> +              dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGPOWER0);
> +       writel(dmc->dram_param[idx].timing_power,
> +              dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGPOWER0);
> +
> +       return 0;
> +}
> +
> +/**
> + * exynos5_switch_timing_regs() - Changes bank register set for DRAM timings
> + * @dmc:       device for which the new settings is going to be applied
> + * @set:       boolean variable passing set value
> + *
> + * Changes the register set, which holds timing parameters.
> + * There is two register sets: 0 and 1. The register set 0
> + * is used in normal operation when the clock is provided from main PLL.
> + * The bank register set 1 is used when the main PLL frequency is going to be
> + * changed and the clock is taken from alternative, stable source.
> + * This function switches between these banks according to the
> + * currently used clock source.
> + */
> +static void exynos5_switch_timing_regs(struct exynos5_dmc *dmc, bool set)
> +{
> +       unsigned int reg;
> +
> +       reg = readl(dmc->base_clk + EXYNOS5_LPDDR3PHY_CON3);
> +
> +       if (set)
> +               reg |= EXYNOS5_TIMING_SET_SWI;
> +       else
> +               reg &= ~EXYNOS5_TIMING_SET_SWI;
> +
> +       writel(reg, dmc->base_clk + EXYNOS5_LPDDR3PHY_CON3);
> +}
> +
> +/*
> + * Change clock parent for MUX_CORE_SEL and the main clock for DMC.
> + * The mux takes two clock sources: main BPLL and mx_mspll ('bypass').
> + */
> +static int exynos5_dmc_change_clock_parent(struct exynos5_dmc *dmc,
> +                                          struct clk *parent,
> +                                          unsigned int parent_selection_id)
> +{
> +       unsigned int reg = 0;
> +
> +       reg = readl(dmc->base_clk + EXYNOS5_CLK_SRC_CDREX);
> +       if (clk_set_parent(dmc->mout_mclk_cdrex, parent)) {
> +               dev_err(dmc->dev, "Couldn't change parent of mclk_cdrex\n");
> +               return -EINVAL;
> +       }
> +
> +       for ( ; reg != parent_selection_id; ) {
> +               cpu_relax();
> +               reg = readl(dmc->base_clk + EXYNOS5_CLK_MUX_STAT_CDREX);
> +               reg >>= EXYNOS5_CLKSRC_CDREX_SEL_SHIFT;
> +               reg &= EXYNOS5_MCLK_CDREX_MASK;
> +       }
> +
> +       return 0;

When handling the clock controller, like changing the parent clock,
you have to use the clock framework. If changing the issue of parent clock,
you should fix the issue on clock driver and then just use the clock api
provided by clock framework(CCF). I can't agree to access the clock register map
directly without the clock framework.

> +}
> +
> +
> +/**
> + * exynos5_dmc_change_voltage() - Changes the voltage regulator value
> + * @dmc:       device for which it is going to be set
> + * @target_volt:       new voltage which is chosen to be final
> + *
> + * Main function for changing voltage on the VDD_MIF regulator.
> + */
> +static int exynos5_dmc_change_voltage(struct exynos5_dmc *dmc,
> +                                     unsigned long target_volt)

Don't  to make it as separate function. Just call the
'regulator_set_voltage' on proper position.

> +{
> +       int ret;
> +
> +       ret = regulator_set_voltage(dmc->vdd_mif, target_volt,
> +                                   target_volt + DMC_REG_VOLT_STEP);
> +
> +       if (ret)
> +               return ret;
> +
> +       dmc->curr_volt = target_volt;
> +
> +       return 0;
> +}
> +
> +/**
> + * exynos5_dmc_align_target_voltage() - Sets the final voltage for the DMC
> + * @dmc:       device for which it is going to be set
> + * @target_volt:       new voltage which is chosen to be final
> + *
> + * Function tries to align voltage to the safe level for 'normal' mode.
> + * It checks the need of higher voltage and changes the value. The target
> + * voltage might be lower that currently set and still the system will be
> + * stable.
> + */
> +static int exynos5_dmc_align_target_voltage(struct exynos5_dmc *dmc,
> +                                           unsigned long target_volt)
> +{


Don't  need to make it as separate function. Just call the
'regulator_set_voltage'
after comparing the current voltage. Please remove the separate function.

> +       int ret = 0;
> +
> +       if (dmc->curr_volt > target_volt)
> +               ret = exynos5_dmc_change_voltage(dmc, target_volt);
> +
> +       return ret;
> +}
> +
> +/**
> + * exynos5_dmc_align_bypass_voltage() - Sets the voltage for the DMC
> + * @dmc:       device for which it is going to be set
> + * @target_volt:       new voltage which is chosen to be final
> + *
> + * Function tries to align voltage to the safe level for the 'bypass' mode.
> + * It checks the need of higher voltage and changes the value.
> + * The target voltage must not be less than currently needed, because
> + * for current frequency the device might become unstable.
> + */
> +static int exynos5_dmc_align_bypass_voltage(struct exynos5_dmc *dmc,
> +                                           unsigned long target_volt)
> +{

This function is called only one time. Don't  need to make it as
separate function.

> +       int ret = 0;
> +       unsigned long bypass_volt = dmc->opp_bypass->volt_uv;
> +
> +       target_volt = max(bypass_volt, target_volt);
> +
> +       if (dmc->curr_volt >= target_volt)
> +               return 0;
> +
> +       ret = exynos5_dmc_change_voltage(dmc, target_volt);
> +
> +       return ret;
> +}
> +
> +/**
> + * exynos5_dmc_align_bypass_dram_timings() - Chooses and sets DRAM timings
> + * @dmc:       device for which it is going to be set
> + * @target_rate:       new frequency which is chosen to be final
> + *
> + * Function changes the DRAM timings for the temporary 'bypass' mode.
> + */
> +static int exynos5_dmc_align_bypass_dram_timings(struct exynos5_dmc *dmc,
> +                                                unsigned long target_rate)

This function is called only one time. Don't  need to make it as
separate function.
If you add the detailed comment about code, it is enought. Please
remove the separate function.

> +{
> +       int idx = find_target_freq_idx(dmc, target_rate);
> +
> +       if (idx < 0)
> +               return -EINVAL;
> +
> +       exynos5_set_bypass_dram_timings(dmc, dmc->dram_bypass_param);
> +
> +       return 0;
> +}
> +
> +/**
> + * exynos5_dmc_switch_to_bypass_configuration() - Switching to temporary clock
> + * @dmc:       DMC device for which the switching is going to happen
> + * @target_rate:       new frequency which is going to be set as a final
> + * @target_volt:       new voltage which is going to be set as a final
> + *
> + * Function configures DMC and clocks for operating in temporary 'bypass' mode.
> + * This mode is used only temporary but if required, changes voltage and timings
> + * for DRAM chips. It switches the main clock to stable clock source for the
> + * period of the main PLL reconfiguration.
> + */
> +static int exynos5_dmc_switch_to_bypass_configuration(struct exynos5_dmc *dmc,
> +                                  unsigned long target_rate,
> +                                  unsigned long target_volt)
> +{
> +       int ret;
> +
> +       /*
> +        * Having higher voltage for a particular frequency does not harm
> +        * the chip. Use it for the temporary frequency change when one
> +        * voltage manipulation might be avoided.
> +        */
> +       ret = exynos5_dmc_align_bypass_voltage(dmc, target_volt);
> +       if (ret)
> +               return ret;
> +
> +       /*
> +        * Longer delays for DRAM does not cause crash, the opposite does.
> +        */
> +       ret = exynos5_dmc_align_bypass_dram_timings(dmc, target_rate);
> +       if (ret)
> +               return ret;
> +
> +       /*
> +        * Delays are long enough, so use them for the new coming clock.
> +        */
> +       exynos5_switch_timing_regs(dmc, USE_MX_MSPLL_TIMINGS);
> +
> +       /*
> +        * Voltage is set at least to a level needed for this frequency,
> +        * so switching clock source is safe now.
> +        */
> +       clk_prepare_enable(dmc->fout_spll);
> +       clk_prepare_enable(dmc->mout_spll);
> +       clk_prepare_enable(dmc->mout_mx_mspll_ccore);
> +       ret = exynos5_dmc_change_clock_parent(dmc, dmc->mout_mx_mspll_ccore,
> +                                             EXYNOS5_MCLK_CDREX_SEL_MX_MSPLL);
> +       return ret;
> +}
> +
> +/**
> + * exynos5_dmc_change_freq_and_volt() - Changes voltage and frequency of the DMC
> + * using safe procedure
> + * @dmc:       device for which the frequency is going to be changed
> + * @target_rate:       requested new frequency
> + * @target_volt:       requested voltage which corresponds to the new frequency
> + *
> + * The DMC frequency change procedure requires a few steps.
> + * The main requirement is to change the clock source in the clk mux
> + * for the time of main clock PLL locking. The assumption is that the
> + * alternative clock source set as parent is stable.
> + * The second parent's clock frequency is fixed to 400MHz, it is named 'bypass'
> + * clock. This requires alignment in DRAM timing parameters for the new
> + * T-period. There is two bank sets for keeping DRAM
> + * timings: set 0 and set 1. The set 0 is used when main clock source is
> + * chosen. The 2nd set of regs is used for 'bypass' clock. Switching between
> + * the two bank sets is part of the process.
> + * The voltage must also be aligned to the minimum required level. There is
> + * this intermediate step with switching to 'bypass' parent clock source.
> + * if the old voltage is lower, it requires an increase of the voltage level.
> + * The complexity of the voltage manipulation is hidden in low level function.
> + * In this function there is last alignment of the voltage level at the end.
> + */
> +static int
> +exynos5_dmc_change_freq_and_volt(struct exynos5_dmc *dmc,
> +                                unsigned long target_rate,
> +                                unsigned long target_volt)
> +{
> +       int ret;
> +
> +       ret = exynos5_dmc_switch_to_bypass_configuration(dmc, target_rate,
> +                                                        target_volt);
> +       if (ret)
> +               return ret;
> +
> +       /* We are safe to increase the timings for current bypass frequency.
> +        * Thanks to this the settings we be ready for the upcoming clock source
> +        * change.
> +        */
> +       exynos5_dram_change_timings(dmc, target_rate);
> +
> +       clk_set_rate(dmc->fout_bpll, target_rate * 1000);
> +
> +       exynos5_switch_timing_regs(dmc, USE_BPLL_TIMINGS);
> +
> +       ret = exynos5_dmc_change_clock_parent(dmc, dmc->mout_bpll,
> +                                             EXYNOS5_MCLK_CDREX_SEL_BPLL);

As I commented already, it is wrong to access the register of clock
controller directly by this driver without clcok framework.

> +       if (ret)
> +               return ret;
> +
> +       clk_disable_unprepare(dmc->mout_mx_mspll_ccore);
> +       clk_disable_unprepare(dmc->mout_spll);
> +       clk_disable_unprepare(dmc->fout_spll);
> +       /* Make sure if the voltage is not from 'bypass' settings and align to
> +        * the right level for power efficiency.
> +        */
> +       ret = exynos5_dmc_align_target_voltage(dmc, target_volt);
> +
> +       return ret;
> +}
> +
> +/**
> + * exynos5_dmc_get_volt_freq() - Gets the frequency and voltage from the OPP
> + * table.
> + * @dev:       device for which the frequency is going to be changed
> + * @freq:       requested frequency in KHz
> + * @target_rate:       returned frequency which is the same or lower than
> + *                     requested
> + * @target_volt:       returned voltage which corresponds to the returned
> + *                     frequency
> + *
> + * Function gets requested frequency and checks OPP framework for needed
> + * frequency and voltage. It populates the values 'target_rate' and
> + * 'target_volt' or returns error value when OPP framework fails.
> + */
> +static int exynos5_dmc_get_volt_freq(struct device *dev, unsigned long *freq,
> +                                    unsigned long *target_rate,
> +                                    unsigned long *target_volt, u32 flags)
> +{
> +       struct dev_pm_opp *opp;
> +
> +       opp = devfreq_recommended_opp(dev, freq, flags);
> +       if (IS_ERR(opp))
> +               return PTR_ERR(opp);
> +
> +       *target_rate = dev_pm_opp_get_freq(opp);
> +       *target_volt = dev_pm_opp_get_voltage(opp);
> +       dev_pm_opp_put(opp);
> +
> +       return 0;
> +}
> +
> +/**
> + * exynos5_dmc_target() - Function responsible for changing frequency of DMC
> + * @dev:       device for which the frequency is going to be changed
> + * @freq:      requested frequency in KHz
> + * @flags:     flags provided for this frequency change request
> + *
> + * An entry function provided to the devfreq framework which provides frequency
> + * change of the DMC. The function gets the possible rate from OPP table based
> + * on requested frequency. It calls the next function responsible for the
> + * frequency and voltage change. In case of failure, does not set 'curr_rate'
> + * and returns error value to the framework.
> + */
> +static int exynos5_dmc_target(struct device *dev, unsigned long *freq,
> +                             u32 flags)
> +{
> +       struct exynos5_dmc *dmc = dev_get_drvdata(dev);
> +       unsigned long target_rate = 0;
> +       unsigned long target_volt = 0;
> +       int ret;
> +
> +       ret = exynos5_dmc_get_volt_freq(dev, freq, &target_rate, &target_volt,
> +                                       flags);
> +       if (ret)
> +               return ret;
> +
> +       if (target_rate == dmc->curr_rate)
> +               return 0;
> +
> +       mutex_lock(&dmc->lock);
> +
> +       ret = exynos5_dmc_change_freq_and_volt(dmc, target_rate, target_volt);
> +
> +       if (ret) {
> +               mutex_unlock(&dmc->lock);
> +               return ret;
> +       }
> +
> +       dmc->curr_rate = target_rate;
> +
> +       mutex_unlock(&dmc->lock);
> +       return 0;
> +}
> +
> +/**
> + * exynos5_cnt_name_match() - Tries to match 'edev' with the right device index
> + * @edev:       event device for which the name is going to be matched
> + *
> + * Function matches the name of the 'edev' counter device with known devices
> + * with configured ratios and shares of the DMC channels.
> + * When the name is matched, it returns the index for the proper device.
> + */
> +static int exynos5_cnt_name_match(struct devfreq_event_dev *edev)

Dont' need to make it as separate function. Just add it to
exynos5_cnt_calculate.

> +{
> +       int i;
> +       int id = -ENODEV;
> +
> +       for (i = 0; i < ARRAY_SIZE(dmc_slot); i++) {
> +               if (strstr(edev->desc->name, dmc_slot[i].name))
> +                       return i;
> +       }
> +
> +       return id;
> +}
> +
> +/**
> + * exynos5_cnt_calculate() - Calculates the values of performance counters.
> + * @edev:      event device for which the counter is used for calculation
> + * @cnt:       raw counter value
> + * @cnt_norm:  counter value normalized to DMC performance ratio for a proper
> + *             channel or virtual channel
> + *
> + * Function calculates normalized value for the raw counter. The raw counter
> + * value does not show real channel usage. The DMC splits not equally the
> + * bandwidth for the channels. The function checks the type of the 'edev'
> + * counter and calculates the normalized value based on the 'shares' of the
> + * bandwidth set in the controller.
> + */
> +static int exynos5_cnt_calculate(struct devfreq_event_dev *edev,
> +                                unsigned long cnt, u64 *cnt_norm)
> +{
> +       int idx;
> +
> +       idx = exynos5_cnt_name_match(edev);
> +       if (idx < 0)
> +               return idx;
> +
> +       *cnt_norm = cnt;
> +
> +       if (!(dmc_slot[idx].ratio_mul == dmc_slot[idx].ratio_div)) {
> +               *cnt_norm = *cnt_norm * dmc_slot[idx].ratio_mul;
> +               *cnt_norm = div_u64(*cnt_norm, dmc_slot[idx].ratio_div);
> +       }
> +
> +       *cnt_norm = *cnt_norm * PMCNT_CONST_RATIO_MUL;
> +       *cnt_norm = div_u64(*cnt_norm, PMCNT_CONST_RATIO_DIV);
> +
> +       return idx;
> +}
> +
> +/**
> + * exynos5_counters_get() - Gets the performance counters values.
> + * @dmc:       device for which the counters are going to be checked
> + * @load_count:        variable which is populated with counter value
> + * @total_count:       variable which is used as 'wall clock' reference
> + *
> + * Function which provides performance counters values. It sums up counters for
> + * two DMC channels. The 'total_count' is used as a reference and max value.
> + * The ratio 'load_count/total_count' shows the busy percentage [0%, 100%].
> + */
> +static int exynos5_counters_get(struct exynos5_dmc *dmc,
> +                               unsigned long *load_count,
> +                               unsigned long *total_count)
> +{
> +       unsigned long load_dmc[2] = {0, 0};
> +       unsigned long total = 0;
> +       u64 load = 0;
> +       struct devfreq_event_data event;
> +       int ret, i, idx;
> +
> +       for (i = 0; i < dmc->num_counters; i++) {
> +               if (!dmc->counter[i])
> +                       continue;
> +
> +               ret = devfreq_event_get_event(dmc->counter[i], &event);
> +               if (ret < 0)
> +                       return ret;
> +
> +               idx = exynos5_cnt_calculate(dmc->counter[i], event.load_count,
> +                                           &load);
> +               if (idx < 0)
> +                       continue;
> +
> +               if (idx == DMC0_0 || idx == DMC0_1)
> +                       load_dmc[0] += load;
> +               else
> +                       load_dmc[1] += load;
> +
> +               if (total < event.total_count)
> +                       total = event.total_count;
> +       }
> +
> +       *load_count = load_dmc[0] + load_dmc[1];
> +       *total_count = total;
> +
> +       return 0;
> +}
> +
> +/**
> + * exynos5_dmc_get_status() - Read current DMC performance statistics.
> + * @dev:       device for which the statistics are requested
> + * @stat:      structure which has statistic fields
> + *
> + * Function reads the DMC performance counters and calculates 'busy_time'
> + * and 'total_time'. To protect from overflow, the values are shifted right
> + * by 10. After read out the counters are setup to count again.
> + */
> +static int exynos5_dmc_get_status(struct device *dev,
> +                                 struct devfreq_dev_status *stat)
> +{
> +       struct exynos5_dmc *dmc = dev_get_drvdata(dev);
> +       unsigned long load, total;
> +       int ret;
> +       bool cnt_en;
> +
> +       mutex_lock(&dmc->lock);
> +       cnt_en = dmc->counters_enabled;
> +       mutex_unlock(&dmc->lock);
> +       if (!cnt_en) {
> +               dev_warn(dev, "performance counters needed, but not present\n");
> +               return -EAGAIN;
> +       }
> +
> +       ret = exynos5_counters_get(dmc, &load, &total);
> +       if (ret < 0)
> +               return -EINVAL;
> +
> +       /* To protect from overflow in calculation ratios, divide by 1024 */
> +       stat->busy_time = load >> 10;
> +       stat->total_time = total >> 10;
> +
> +       ret = exynos5_counters_set_event(dmc);
> +       if (ret < 0) {
> +               dev_err(dmc->dev, "could not set event counter\n");
> +               return ret;
> +       }
> +
> +       return 0;
> +}
> +
> +/**
> + * exynos5_dmc_get_cur_freq() - Function returns current DMC frequency
> + * @dev:       device for which the framework checks operating frequency
> + * @freq:      returned frequency value
> + *
> + * It returns the currently used frequency of the DMC. The real operating
> + * frequency might be lower when the clock source value could not be divided
> + * to the requested value.
> + */
> +static int exynos5_dmc_get_cur_freq(struct device *dev, unsigned long *freq)
> +{
> +       struct exynos5_dmc *dmc = dev_get_drvdata(dev);
> +
> +       mutex_lock(&dmc->lock);
> +       *freq = dmc->curr_rate;
> +       mutex_unlock(&dmc->lock);
> +
> +       return 0;
> +}
> +
> +/**
> + * exynos5_dmc_df_profile - Devfreq governor's profile structure
> + *
> + * It provides to the devfreq framework needed functions and polling period.
> + */
> +static struct devfreq_dev_profile exynos5_dmc_df_profile = {
> +       .polling_ms = 500,

Is it right? IMO, 500 ms is too late for ondemand governor.

> +       .target = exynos5_dmc_target,
> +       .get_dev_status = exynos5_dmc_get_status,
> +       .get_cur_freq = exynos5_dmc_get_cur_freq,
> +};
> +
> +/**
> + * exynos5_dmc_align_initial_frequency() - Align initial frequency value
> + * @dmc:       device for which the frequency is going to be set
> + * @bootloader_init_freq:      initial frequency set by the bootloader in KHz
> + *
> + * The initial bootloader frequency, which is present during boot, might be
> + * different that supported frequency values in the driver. It is possible
> + * due to different PLL settings or used PLL as a source.
> + * This function provides the 'initial_freq' for the devfreq framework
> + * statistics engine which supports only registered values. Thus, some alignment
> + * must be made.
> + */
> +unsigned long
> +exynos5_dmc_align_init_freq(struct exynos5_dmc *dmc,
> +                           unsigned long bootloader_init_freq)
> +{
> +       unsigned long aligned_freq;
> +       int idx;
> +
> +       idx = find_target_freq_idx(dmc, bootloader_init_freq);
> +       if (idx >= 0)
> +               aligned_freq = dmc->opp[idx].freq_khz;
> +       else
> +               aligned_freq = dmc->opp[dmc->opp_count - 1].freq_khz;
> +
> +       return aligned_freq;
> +}
> +
> +/**
> + * exynos5_dmc_init_clks() - Initialize clocks needed for DMC operation.
> + * @dev:       device for which the clocks are setup
> + * @dmc:       DMC structure containing needed fields
> + *
> + * Get the needed clocks defined in DT device, enable and set the right parents.
> + * Read current frequency and initialize the initial rate for governor.
> + */
> +static int exynos5_dmc_init_clks(struct device *dev, struct exynos5_dmc *dmc)
> +{
> +       int ret;
> +       unsigned long target_volt = 0;
> +       unsigned long target_rate = 0;
> +
> +       dmc->fout_spll = devm_clk_get(dev, "fout_spll");
> +       if (IS_ERR(dmc->fout_spll))
> +               return PTR_ERR(dmc->fout_spll);
> +
> +       dmc->fout_bpll = devm_clk_get(dev, "fout_bpll");
> +       if (IS_ERR(dmc->fout_bpll))
> +               return PTR_ERR(dmc->fout_bpll);
> +
> +       dmc->mout_mclk_cdrex = devm_clk_get(dev, "mout_mclk_cdrex");
> +       if (IS_ERR(dmc->mout_mclk_cdrex))
> +               return PTR_ERR(dmc->mout_mclk_cdrex);
> +
> +       dmc->mout_bpll = devm_clk_get(dev, "mout_bpll");
> +       if (IS_ERR(dmc->mout_bpll))
> +               return PTR_ERR(dmc->mout_bpll);
> +
> +       dmc->mout_mx_mspll_ccore = devm_clk_get(dev, "mout_mx_mspll_ccore");
> +       if (IS_ERR(dmc->mout_mx_mspll_ccore))
> +               return PTR_ERR(dmc->mout_mx_mspll_ccore);
> +
> +       dmc->dout_clk2x_phy0 = devm_clk_get(dev, "dout_clk2x_phy0");
> +       if (IS_ERR(dmc->dout_clk2x_phy0))
> +               return PTR_ERR(dmc->dout_clk2x_phy0);
> +
> +       dmc->mout_spll = devm_clk_get(dev, "ff_dout_spll2");
> +       if (IS_ERR(dmc->mout_spll))
> +               return PTR_ERR(dmc->mout_spll);
> +

I don't understand why do you get the parent clocks and hanel them directly?
You make the hierarchy between clocks by using 'assigned-clocks,
assigned-clock-parents' property on devicetree. It was too legacy
style to make the hierarchy directly on device driver. You can easily
refer to 'assigned-clocks, assigned-clock-parents' examples on exynos
dts files.

> +       /*
> +        * Convert frequency to KHz values and set it for the governor.
> +        */
> +       dmc->curr_rate = clk_get_rate(dmc->mout_mclk_cdrex) / 1000;
> +       dmc->curr_rate = exynos5_dmc_align_init_freq(dmc, dmc->curr_rate);
> +       exynos5_dmc_df_profile.initial_freq = dmc->curr_rate;
> +
> +       ret = exynos5_dmc_get_volt_freq(dev, &dmc->curr_rate, &target_rate,
> +                                       &target_volt, 0);
> +       if (ret)
> +               return ret;
> +
> +       dmc->curr_volt = target_volt;
> +
> +       clk_prepare_enable(dmc->mout_spll);
> +       clk_set_parent(dmc->mout_mx_mspll_ccore, dmc->mout_spll);
> +       clk_prepare_enable(dmc->mout_mx_mspll_ccore);
> +
> +       clk_prepare_enable(dmc->fout_bpll);
> +       clk_prepare_enable(dmc->mout_bpll);
> +
> +       return 0;
> +}
> +
> +/**
> + * exynos5_performance_counters_init() - Initializes performance DMC's counters
> + * @dmc:       DMC for which it does the setup
> + *
> + * Initialization of performance counters in DMC for estimating usage.
> + * The counter's values are used for calculation of a memory bandwidth and based
> + * on that the governor changes the frequency.
> + * The counters are not used when the governor is GOVERNOR_USERSPACE.
> + */
> +static int exynos5_performance_counters_init(struct exynos5_dmc *dmc)
> +{
> +       int counters_size;
> +       int ret, i;
> +
> +       dmc->num_counters = devfreq_event_get_edev_count(dmc->dev);
> +       if (dmc->num_counters < 0) {
> +               dev_err(dmc->dev, "could not get devfreq-event counters\n");
> +               return dmc->num_counters;
> +       }
> +
> +       counters_size = sizeof(struct devfreq_event_dev) * dmc->num_counters;
> +       dmc->counter = devm_kzalloc(dmc->dev, counters_size, GFP_KERNEL);
> +       if (!dmc->counter)
> +               return -ENOMEM;
> +
> +       for (i = 0; i < dmc->num_counters; i++) {
> +               dmc->counter[i] =
> +                       devfreq_event_get_edev_by_phandle(dmc->dev, i);
> +               if (IS_ERR_OR_NULL(dmc->counter[i]))
> +                       return -EPROBE_DEFER;
> +       }
> +
> +       ret = exynos5_counters_enable_edev(dmc);
> +       if (ret < 0) {
> +               dev_err(dmc->dev, "could not enable event counter\n");
> +               return ret;
> +       }
> +
> +       ret = exynos5_counters_set_event(dmc);
> +       if (ret < 0) {
> +               dev_err(dmc->dev, "counld not set event counter\n");
> +               return ret;
> +       }
> +
> +       mutex_lock(&dmc->lock);
> +       dmc->counters_enabled = true;
> +       mutex_unlock(&dmc->lock);
> +
> +       return 0;
> +}
> +
> +/**
> + * exynos5_dmc_probe() - Probe function for the DMC driver
> + * @pdev:      platform device for which the driver is going to be initialized
> + *
> + * Initialize basic components: clocks, regulators, performance counters, etc.
> + * Read out product version and based on the information setup
> + * internal structures for the controller (frequency and voltage) and for DRAM
> + * memory parameters: timings for each operating frequency.
> + * Register new devfreq device for controlling DVFS of the DMC.
> + */
> +static int exynos5_dmc_probe(struct platform_device *pdev)
> +{
> +       int ret = 0;
> +       struct exynos5_dmc *dmc;
> +       struct device *dev = &pdev->dev;
> +       struct resource *res;
> +
> +       dmc = devm_kzalloc(dev, sizeof(*dmc), GFP_KERNEL);
> +       if (!dmc)
> +               return -ENOMEM;
> +
> +       mutex_init(&dmc->lock);
> +
> +       dmc->dev = dev;
> +       platform_set_drvdata(pdev, dmc);
> +
> +       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +       dmc->base_drexi0 = devm_ioremap_resource(dev, res);
> +       if (IS_ERR(dmc->base_drexi0))
> +               return PTR_ERR(dmc->base_drexi0);
> +
> +       res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> +       dmc->base_drexi1 = devm_ioremap_resource(dev, res);
> +       if (IS_ERR(dmc->base_drexi1))
> +               return PTR_ERR(dmc->base_drexi1);
> +
> +       res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
> +       dmc->base_clk = devm_ioremap_resource(dev, res);
> +       if (IS_ERR(dmc->base_clk))
> +               return PTR_ERR(dmc->base_clk);
> +
> +       res = platform_get_resource(pdev, IORESOURCE_MEM, 3);
> +       dmc->chip_id = devm_ioremap_resource(dev, res);
> +       if (IS_ERR(dmc->chip_id))
> +               return PTR_ERR(dmc->chip_id);
> +
> +       ret = exynos5_dmc_chip_revision_settings(dmc);
> +       if (ret)
> +               return ret;
> +
> +       ret = exynos5_init_freq_table(dev, dmc, &exynos5_dmc_df_profile);
> +       if (ret)
> +               return ret;
> +
> +       dmc->vdd_mif = devm_regulator_get(dev, "vdd_mif");
> +       if (IS_ERR(dmc->vdd_mif)) {
> +               ret = PTR_ERR(dmc->vdd_mif);
> +               dev_warn(dev, "couldn't get regulator\n");
> +               goto remove_opp_table;
> +       }
> +
> +       ret = exynos5_dmc_init_clks(dev, dmc);
> +       if (ret) {
> +               dev_warn(dev, "couldn't initialize clocks\n");
> +               goto remove_opp_table;
> +       }
> +
> +       ret = exynos5_dmc_pause_on_switching(dmc, 1);
> +       if (ret) {
> +               dev_warn(dev, "couldn't setup pause on switching\n");
> +               goto remove_clocks;
> +       }
> +
> +       ret = exynos5_performance_counters_init(dmc);
> +       if (ret) {
> +               dev_warn(dev, "couldn't probe performance counters\n");
> +               goto remove_clocks;
> +       }
> +       /*
> +        * Setup default thresholds for the devfreq governor.
> +        * The values are chosen based on experiments.
> +        */
> +       dmc->gov_data.upthreshold = 30;
> +       dmc->gov_data.downdifferential = 5;
> +
> +       dmc->df = devm_devfreq_add_device(dev, &exynos5_dmc_df_profile,
> +                                         DEVFREQ_GOV_USERSPACE,
> +                                         &dmc->gov_data);
> +
> +       if (IS_ERR(dmc->df)) {
> +               ret = PTR_ERR(dmc->df);
> +               goto err_devfreq_add;
> +       }
> +
> +       dev_info(&pdev->dev, "DMC init for prod_id=0x%08x pkg_id=0x%08x\n",
> +                dmc->prod_rev, dmc->pkg_rev);
> +
> +       return 0;
> +
> +err_devfreq_add:
> +       exynos5_counters_disable_edev(dmc);
> +remove_clocks:
> +       clk_disable_unprepare(dmc->mout_mx_mspll_ccore);
> +       clk_disable_unprepare(dmc->mout_spll);
> +remove_opp_table:
> +       while (dmc->opp_count-- > 0)
> +               dev_pm_opp_remove(dev, dmc->opp[dmc->opp_count].freq_khz);
> +
> +       return ret;
> +}
> +
> +/**
> + * exynos5_dmc_remove() - Remove function for the platform device
> + * @pdev:      platform device which is going to be removed
> + *
> + * The function relies on 'devm' framework function which automatically
> + * clean the device's resources. It just calls explicitly disable function for
> + * the performance counters.
> + */
> +static int exynos5_dmc_remove(struct platform_device *pdev)
> +{
> +       struct exynos5_dmc *dmc = dev_get_drvdata(&pdev->dev);
> +
> +       exynos5_counters_disable_edev(dmc);
> +
> +       clk_disable_unprepare(dmc->mout_mx_mspll_ccore);
> +       clk_disable_unprepare(dmc->mout_spll);
> +
> +       dev_pm_opp_remove_table(&pdev->dev);
> +
> +       dev_info(&pdev->dev, "DMC removed\n");
> +
> +       return 0;
> +}
> +
> +static const struct of_device_id exynos5_dmc_of_match[] = {
> +       { .compatible = "samsung,exynos5422-dmc", },
> +       { },
> +};
> +MODULE_DEVICE_TABLE(of, exynos5_dmc_of_match);
> +
> +static struct platform_driver exynos5_dmc_platdrv = {
> +       .probe  = exynos5_dmc_probe,
> +       .remove = exynos5_dmc_remove,
> +       .driver = {
> +               .name   = "exynos5-dmc",
> +               .of_match_table = exynos5_dmc_of_match,
> +       },
> +};
> +module_platform_driver(exynos5_dmc_platdrv);
> +MODULE_DESCRIPTION(DRIVER_DESC);
> +MODULE_LICENSE("GPL v2");
> +MODULE_AUTHOR("Samsung");
> --
> 2.7.4
>


-- 
Best Regards,
Chanwoo Choi

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Re: [PATCH v4 4/8] drivers: devfreq: add DMC driver for Exynos5422

[Sylwester Nawrocki]

Hi,

On 2/3/19 13:23, Chanwoo Choi wrote:

> 2019년 2월 2일 (토) 오전 2:42, Lukasz Luba <l.luba@partner.samsung.com>님이 작성:

>> +/**
>> + * exynos5_dmc_pause_on_switching() - Controls a pause feature in DMC
>> + * @dmc:       device which is used for changing this feature
>> + * @set:       a boolean state passing enable/disable request
>> + *
>> + * There is a need of pausing DREX DMC when divider or MUX in clock tree
>> + * changes its configuration. In such situation access to the memory is blocked
>> + * in DMC automatically. This feature is used when clock frequency change
>> + * request appears and touches clock tree.
>> + */
>> +static int exynos5_dmc_pause_on_switching(struct exynos5_dmc *dmc, bool set)
> 
> Don't need to make it as the separate function. It is only used on
> probe() function.

It seems fine to me to have this functionality in a separate function, 
it's self-contained and it's now pretty well documented.

>> +{
>> +       unsigned int val;
>> +
>> +       val = readl(dmc->base_clk + DMC_PAUSE_CTRL);
>> +       if (set)
>> +               val |= DMC_PAUSE_ENABLE;
>> +       else
>> +               val &= ~DMC_PAUSE_ENABLE;
>> +       writel(val, dmc->base_clk + DMC_PAUSE_CTRL);
> 
> The dt-binding file doesn't explain the 'reg' property for 'base_clk'.
> You are missing.
> When I tried to find what are the base address, it is the register map
> of clock-controller.
> This driver accesed the register of clock controller without any
> functions of CCF
> (common clock framework). It is wrong.
> 
> If you need to get the some information of clock, must have to use the CCF.
We talked a little about this issue with Lukasz in person and it looks
like there are some DMC related registers in the clock controller register 
region, I'd say those registers are better handled by the DMC driver rather
than the clocks controller driver. Moreover, we should avoid abusing clk API
for not strictly clocks related functionality as it appears to be above.
It might be more appropriate to add in the dmc DT node a phandle to a regmap
exposed by the clock-controller node. It seems there will be even no single
register that would be shared between the DMC and the clock controller.

-- 
Regards,
Sylwester

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Re: [PATCH v4 4/8] drivers: devfreq: add DMC driver for Exynos5422

[Chanwoo Choi]

Hi Sylwester,

On 19. 3. 6. 오후 10:44, Sylwester Nawrocki wrote:
> Hi,
> 
> On 2/3/19 13:23, Chanwoo Choi wrote:
> 
>> 2019년 2월 2일 (토) 오전 2:42, Lukasz Luba <l.luba@partner.samsung.com>님이 작성:
> 
>>> +/**
>>> + * exynos5_dmc_pause_on_switching() - Controls a pause feature in DMC
>>> + * @dmc:       device which is used for changing this feature
>>> + * @set:       a boolean state passing enable/disable request
>>> + *
>>> + * There is a need of pausing DREX DMC when divider or MUX in clock tree
>>> + * changes its configuration. In such situation access to the memory is blocked
>>> + * in DMC automatically. This feature is used when clock frequency change
>>> + * request appears and touches clock tree.
>>> + */
>>> +static int exynos5_dmc_pause_on_switching(struct exynos5_dmc *dmc, bool set)
>>
>> Don't need to make it as the separate function. It is only used on
>> probe() function.
> 
> It seems fine to me to have this functionality in a separate function, 
> it's self-contained and it's now pretty well documented.
> 
>>> +{
>>> +       unsigned int val;
>>> +
>>> +       val = readl(dmc->base_clk + DMC_PAUSE_CTRL);
>>> +       if (set)
>>> +               val |= DMC_PAUSE_ENABLE;
>>> +       else
>>> +               val &= ~DMC_PAUSE_ENABLE;
>>> +       writel(val, dmc->base_clk + DMC_PAUSE_CTRL);
>>
>> The dt-binding file doesn't explain the 'reg' property for 'base_clk'.
>> You are missing.
>> When I tried to find what are the base address, it is the register map
>> of clock-controller.
>> This driver accesed the register of clock controller without any
>> functions of CCF
>> (common clock framework). It is wrong.
>>
>> If you need to get the some information of clock, must have to use the CCF.
> We talked a little about this issue with Lukasz in person and it looks
> like there are some DMC related registers in the clock controller register 
> region, I'd say those registers are better handled by the DMC driver rather
> than the clocks controller driver. Moreover, we should avoid abusing clk API
> for not strictly clocks related functionality as it appears to be above.
> It might be more appropriate to add in the dmc DT node a phandle to a regmap
> exposed by the clock-controller node. It seems there will be even no single
> register that would be shared between the DMC and the clock controller.
> 

I agree to share the regmap instance of clock controller
with syscon_regmap_lookup_by_phandle() and then add the detailed
description about this to dt-binding documentation.


And,
This patch has the another quetion about the clocks in
exynos5_dmc_init_clks(). This functions used 'clk_set_parent'
to make the hierarchy between clocks. I think it is possible to make
the relation of clocks in DT by using the 'assigned-clocks'.

-- 
Best Regards,
Chanwoo Choi
Samsung Electronics

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Re: [PATCH v4 4/8] drivers: devfreq: add DMC driver for Exynos5422

[Sylwester Nawrocki]

Hi Chanwoo,

On 3/7/19 02:10, Chanwoo Choi wrote:
> This patch has the another quetion about the clocks in
> exynos5_dmc_init_clks(). This functions used 'clk_set_parent'
> to make the hierarchy between clocks. I think it is possible to make
> the relation of clocks in DT by using the 'assigned-clocks'.

I'm fine either way, AFAICS it is a matter of setting parent of just
one clock - "mout_mx_mspll_ccore".  The driver needs to get that clock
anyway to enable/disable it as required.  So we will not gain much from
using assigned-clocks I'd say. I don't really have a strong opinion here
as I don't know detailed requirements of the DMC clock configuration
sequence. I'm inclined to keep it in driver as it would be more flexible.

-- 
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Sylwester

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[PATCH v4 5/8] dt-bindings: devfreq: add Exynos5422 DMC device description

[Lukasz Luba]

The patch adds description for DT binding for a new Exynos5422 Dynamic
Memory Controller device.
It also contains needed MAINTAINERS file update.

Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
---
 .../devicetree/bindings/devfreq/exynos5422-dmc.txt | 106 +++++++++++++++++++++
 MAINTAINERS                                        |   1 +
 2 files changed, 107 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/devfreq/exynos5422-dmc.txt

diff --git a/Documentation/devicetree/bindings/devfreq/exynos5422-dmc.txt b/Documentation/devicetree/bindings/devfreq/exynos5422-dmc.txt
new file mode 100644
index 0000000..229efba
--- /dev/null
+++ b/Documentation/devicetree/bindings/devfreq/exynos5422-dmc.txt
@@ -0,0 +1,106 @@
+* Exynos5422 frequency and voltage scaling for Dynamic Memory Controller device
+
+The Samsung Exynos5422 SoC has DMC (Dynamic Memory Controller) to which the DRAM
+memory chips are connected. The driver is to monitor the controller in runtime
+and switch frequency and voltage. To monitor the usage of the controller in
+runtime, the driver uses the PPMU (Platform Performance Monitoring Unit), which
+is able to measure the current load of the memory.
+When 'userspace' governor is used for the driver, an application is able to
+switch the DMC frequency.
+
+Required properties for DMC device for Exynos5422:
+- compatible: Should be "samsung,exynos5422-bus".
+- clock-names : the name of clock used by the bus, "bus".
+- clocks : phandles for clock specified in "clock-names" property.
+- devfreq-events : phandles for PPMU devices connected to this DMC.
+
+The example definition of a DMC and PPMU devices declared in DT is shown below:
+
+	ppmu_dmc0_0: ppmu@10d00000 {
+		compatible = "samsung,exynos-ppmu";
+		reg = <0x10d00000 0x2000>;
+		clocks = <&clock CLK_PCLK_PPMU_DREX0_0>;
+		clock-names = "ppmu";
+		status = "okay";
+		events {
+			ppmu_event_dmc0_0: ppmu-event3-dmc0_0 {
+				event-name = "ppmu-event3-dmc0_0";
+			};
+		};
+	};
+
+
+	ppmu_dmc0_1: ppmu@10d10000 {
+		compatible = "samsung,exynos-ppmu";
+		reg = <0x10d10000 0x2000>;
+		clocks = <&clock CLK_PCLK_PPMU_DREX0_1>;
+		clock-names = "ppmu";
+		status = "okay";
+		events {
+			ppmu_event_dmc0_1: ppmu-event3-dmc0_1 {
+				event-name = "ppmu-event3-dmc0_1";
+			};
+		};
+	};
+
+	ppmu_dmc1_0: ppmu@10d10000 {
+		compatible = "samsung,exynos-ppmu";
+		reg = <0x10d60000 0x2000>;
+		clocks = <&clock CLK_PCLK_PPMU_DREX1_0>;
+		clock-names = "ppmu";
+		status = "okay";
+		events {
+			ppmu_event_dmc1_0: ppmu-event3-dmc1_0 {
+				event-name = "ppmu-event3-dmc1_0";
+			};
+		};
+	};
+
+	ppmu_dmc1_1: ppmu@10d70000 {
+		compatible = "samsung,exynos-ppmu";
+		reg = <0x10d70000 0x2000>;
+		clocks = <&clock CLK_PCLK_PPMU_DREX1_1>;
+		clock-names = "ppmu";
+		status = "okay";
+		events {
+			ppmu_event_dmc1_1: ppmu-event3-dmc1_1 {
+				event-name = "ppmu-event3-dmc1_1";
+			};
+		};
+	};
+
+	dmc: memory-controller@10c20000 {
+		compatible = "samsung,exynos5422-dmc";
+		reg = <0x10c20000 0x10000>, <0x10c30000 0x10000>,
+			<0x10030000 0x1000>, <0x10000000 0x1000>;
+		clocks = 	<&clock CLK_FOUT_SPLL>,
+				<&clock CLK_MOUT_SCLK_SPLL>,
+				<&clock CLK_FF_DOUT_SPLL2>,
+				<&clock CLK_FOUT_BPLL>,
+				<&clock CLK_MOUT_BPLL>,
+				<&clock CLK_SCLK_BPLL>,
+				<&clock CLK_MOUT_MX_MSPLL_CCORE>,
+				<&clock CLK_MOUT_MX_MSPLL_CCORE_PHY>,
+				<&clock CLK_MOUT_MCLK_CDREX>,
+				<&clock CLK_DOUT_CLK2X_PHY0>,
+				<&clock CLK_CLKM_PHY0>,
+				<&clock CLK_CLKM_PHY1>;
+		clock-names =	"fout_spll",
+				"mout_sclk_spll",
+				"ff_dout_spll2",
+				"fout_bpll",
+				"mout_bpll",
+				"sclk_bpll",
+				"mout_mx_mspll_ccore",
+				"mout_mx_mspll_ccore_phy",
+				"mout_mclk_cdrex",
+				"dout_clk2x_phy0",
+				"clkm_phy0",
+				"clkm_phy1";
+
+		status = "okay";
+		devfreq-events = <&ppmu_dmc0_0>, <&ppmu_dmc0_1>,
+				<&ppmu_dmc1_0>, <&ppmu_dmc1_1>;
+	};
+
+
diff --git a/MAINTAINERS b/MAINTAINERS
index e81dfbf..ab0d8a5 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3316,6 +3316,7 @@ L:	linux-pm@vger.kernel.org
 L:	linux-samsung-soc@vger.kernel.org
 S:	Maintained
 F:	drivers/devfreq/exynos5422-dmc.c
+F:	Documentation/devicetree/bindings/devfreq/exynos5422-dmc.txt
 
 BUSLOGIC SCSI DRIVER
 M:	Khalid Aziz <khalid@gonehiking.org>
-- 
2.7.4


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Re: [PATCH v4 5/8] dt-bindings: devfreq: add Exynos5422 DMC device description

[Chanwoo Choi]

 Hi,

2019년 2월 2일 (토) 오전 2:45, Lukasz Luba <l.luba@partner.samsung.com>님이 작성:
>
> The patch adds description for DT binding for a new Exynos5422 Dynamic
> Memory Controller device.
> It also contains needed MAINTAINERS file update.
>
> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
> ---
>  .../devicetree/bindings/devfreq/exynos5422-dmc.txt | 106 +++++++++++++++++++++
>  MAINTAINERS                                        |   1 +
>  2 files changed, 107 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/devfreq/exynos5422-dmc.txt
>
> diff --git a/Documentation/devicetree/bindings/devfreq/exynos5422-dmc.txt b/Documentation/devicetree/bindings/devfreq/exynos5422-dmc.txt
> new file mode 100644
> index 0000000..229efba
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/devfreq/exynos5422-dmc.txt
> @@ -0,0 +1,106 @@
> +* Exynos5422 frequency and voltage scaling for Dynamic Memory Controller device
> +
> +The Samsung Exynos5422 SoC has DMC (Dynamic Memory Controller) to which the DRAM
> +memory chips are connected. The driver is to monitor the controller in runtime
> +and switch frequency and voltage. To monitor the usage of the controller in
> +runtime, the driver uses the PPMU (Platform Performance Monitoring Unit), which
> +is able to measure the current load of the memory.
> +When 'userspace' governor is used for the driver, an application is able to
> +switch the DMC frequency.
> +
> +Required properties for DMC device for Exynos5422:
> +- compatible: Should be "samsung,exynos5422-bus".

The compatible name is wrong.
- exynos5422-bus -> exynos5422-dmc

> +- clock-names : the name of clock used by the bus, "bus".

'bus' is right?

> +- clocks : phandles for clock specified in "clock-names" property.
> +- devfreq-events : phandles for PPMU devices connected to this DMC.

The dt-binging file doesn't contain the any description for 'reg' properties.

> +
> +The example definition of a DMC and PPMU devices declared in DT is shown below:
> +
> +       ppmu_dmc0_0: ppmu@10d00000 {
> +               compatible = "samsung,exynos-ppmu";
> +               reg = <0x10d00000 0x2000>;
> +               clocks = <&clock CLK_PCLK_PPMU_DREX0_0>;
> +               clock-names = "ppmu";
> +               status = "okay";
> +               events {
> +                       ppmu_event_dmc0_0: ppmu-event3-dmc0_0 {
> +                               event-name = "ppmu-event3-dmc0_0";
> +                       };
> +               };
> +       };
> +
> +
> +       ppmu_dmc0_1: ppmu@10d10000 {
> +               compatible = "samsung,exynos-ppmu";
> +               reg = <0x10d10000 0x2000>;
> +               clocks = <&clock CLK_PCLK_PPMU_DREX0_1>;
> +               clock-names = "ppmu";
> +               status = "okay";
> +               events {
> +                       ppmu_event_dmc0_1: ppmu-event3-dmc0_1 {
> +                               event-name = "ppmu-event3-dmc0_1";
> +                       };
> +               };
> +       };
> +
> +       ppmu_dmc1_0: ppmu@10d10000 {
> +               compatible = "samsung,exynos-ppmu";
> +               reg = <0x10d60000 0x2000>;
> +               clocks = <&clock CLK_PCLK_PPMU_DREX1_0>;
> +               clock-names = "ppmu";
> +               status = "okay";
> +               events {
> +                       ppmu_event_dmc1_0: ppmu-event3-dmc1_0 {
> +                               event-name = "ppmu-event3-dmc1_0";
> +                       };
> +               };
> +       };
> +
> +       ppmu_dmc1_1: ppmu@10d70000 {
> +               compatible = "samsung,exynos-ppmu";
> +               reg = <0x10d70000 0x2000>;
> +               clocks = <&clock CLK_PCLK_PPMU_DREX1_1>;
> +               clock-names = "ppmu";
> +               status = "okay";
> +               events {
> +                       ppmu_event_dmc1_1: ppmu-event3-dmc1_1 {
> +                               event-name = "ppmu-event3-dmc1_1";
> +                       };
> +               };
> +       };
> +
> +       dmc: memory-controller@10c20000 {
> +               compatible = "samsung,exynos5422-dmc";
> +               reg = <0x10c20000 0x10000>, <0x10c30000 0x10000>,
> +                       <0x10030000 0x1000>, <0x10000000 0x1000>;
> +               clocks =        <&clock CLK_FOUT_SPLL>,
> +                               <&clock CLK_MOUT_SCLK_SPLL>,
> +                               <&clock CLK_FF_DOUT_SPLL2>,
> +                               <&clock CLK_FOUT_BPLL>,
> +                               <&clock CLK_MOUT_BPLL>,
> +                               <&clock CLK_SCLK_BPLL>,
> +                               <&clock CLK_MOUT_MX_MSPLL_CCORE>,
> +                               <&clock CLK_MOUT_MX_MSPLL_CCORE_PHY>,
> +                               <&clock CLK_MOUT_MCLK_CDREX>,
> +                               <&clock CLK_DOUT_CLK2X_PHY0>,
> +                               <&clock CLK_CLKM_PHY0>,
> +                               <&clock CLK_CLKM_PHY1>;
> +               clock-names =   "fout_spll",
> +                               "mout_sclk_spll",
> +                               "ff_dout_spll2",
> +                               "fout_bpll",
> +                               "mout_bpll",
> +                               "sclk_bpll",
> +                               "mout_mx_mspll_ccore",
> +                               "mout_mx_mspll_ccore_phy",
> +                               "mout_mclk_cdrex",
> +                               "dout_clk2x_phy0",
> +                               "clkm_phy0",
> +                               "clkm_phy1";
> +
> +               status = "okay";
> +               devfreq-events = <&ppmu_dmc0_0>, <&ppmu_dmc0_1>,
> +                               <&ppmu_dmc1_0>, <&ppmu_dmc1_1>;
> +       };
> +
> +
> diff --git a/MAINTAINERS b/MAINTAINERS
> index e81dfbf..ab0d8a5 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -3316,6 +3316,7 @@ L:        linux-pm@vger.kernel.org
>  L:     linux-samsung-soc@vger.kernel.org
>  S:     Maintained
>  F:     drivers/devfreq/exynos5422-dmc.c
> +F:     Documentation/devicetree/bindings/devfreq/exynos5422-dmc.txt
>
>  BUSLOGIC SCSI DRIVER
>  M:     Khalid Aziz <khalid@gonehiking.org>
> --
> 2.7.4
>


-- 
Best Regards,
Chanwoo Choi

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[PATCH v4 6/8] DT: arm: exynos: add DMC device for exynos5422

[Lukasz Luba]

Add description of Dynamic Memory Controller and PPMU counters.
They are used by exynos5422-dmc driver.

Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
---
 arch/arm/boot/dts/exynos5420.dtsi             | 78 +++++++++++++++++++++++++++
 arch/arm/boot/dts/exynos5422-odroid-core.dtsi | 22 ++++++++
 2 files changed, 100 insertions(+)

diff --git a/arch/arm/boot/dts/exynos5420.dtsi b/arch/arm/boot/dts/exynos5420.dtsi
index aaff158..574d398 100644
--- a/arch/arm/boot/dts/exynos5420.dtsi
+++ b/arch/arm/boot/dts/exynos5420.dtsi
@@ -235,6 +235,36 @@
 			status = "disabled";
 		};
 
+		dmc: memory-controller@10c20000 {
+			compatible = "samsung,exynos5422-dmc";
+			reg = <0x10c20000 0x10000>, <0x10c30000 0x10000>,
+				<0x10030000 0x1000>, <0x10000000 0x1000>;
+			clocks = <&clock CLK_FOUT_SPLL>,
+				 <&clock CLK_MOUT_SCLK_SPLL>,
+				 <&clock CLK_FF_DOUT_SPLL2>,
+				 <&clock CLK_FOUT_BPLL>,
+				 <&clock CLK_MOUT_BPLL>,
+				 <&clock CLK_SCLK_BPLL>,
+				 <&clock CLK_MOUT_MX_MSPLL_CCORE>,
+				 <&clock CLK_MOUT_MX_MSPLL_CCORE_PHY>,
+				 <&clock CLK_MOUT_MCLK_CDREX>,
+				 <&clock CLK_DOUT_CLK2X_PHY0>,
+				 <&clock CLK_CLKM_PHY0>,
+				 <&clock CLK_CLKM_PHY1>;
+			clock-names = "fout_spll",
+				      "mout_sclk_spll",
+				      "ff_dout_spll2",
+				      "fout_bpll",
+				      "mout_bpll",
+				      "sclk_bpll",
+				      "mout_mx_mspll_ccore",
+				      "mout_mx_mspll_ccore_phy",
+				      "mout_mclk_cdrex",
+				      "dout_clk2x_phy0",
+				      "clkm_phy0",
+				      "clkm_phy1";
+		};
+
 		nocp_mem0_0: nocp@10ca1000 {
 			compatible = "samsung,exynos5420-nocp";
 			reg = <0x10CA1000 0x200>;
@@ -271,6 +301,54 @@
 			status = "disabled";
 		};
 
+		ppmu_dmc0_0: ppmu@10d00000 {
+			compatible = "samsung,exynos-ppmu";
+			reg = <0x10d00000 0x2000>;
+			clocks = <&clock CLK_PCLK_PPMU_DREX0_0>;
+			clock-names = "ppmu";
+			events {
+				ppmu_event_dmc0_0: ppmu-event3-dmc0_0 {
+					event-name = "ppmu-event3-dmc0_0";
+				};
+			};
+		};
+
+		ppmu_dmc0_1: ppmu@10d10000 {
+			compatible = "samsung,exynos-ppmu";
+			reg = <0x10d10000 0x2000>;
+			clocks = <&clock CLK_PCLK_PPMU_DREX0_1>;
+			clock-names = "ppmu";
+			events {
+				ppmu_event_dmc0_1: ppmu-event3-dmc0_1 {
+					event-name = "ppmu-event3-dmc0_1";
+				};
+			};
+		};
+
+		ppmu_dmc1_0: ppmu@10d10000 {
+			compatible = "samsung,exynos-ppmu";
+			reg = <0x10d60000 0x2000>;
+			clocks = <&clock CLK_PCLK_PPMU_DREX1_0>;
+			clock-names = "ppmu";
+			events {
+				ppmu_event_dmc1_0: ppmu-event3-dmc1_0 {
+					event-name = "ppmu-event3-dmc1_0";
+				};
+			};
+		};
+
+		ppmu_dmc1_1: ppmu@10d70000 {
+			compatible = "samsung,exynos-ppmu";
+			reg = <0x10d70000 0x2000>;
+			clocks = <&clock CLK_PCLK_PPMU_DREX1_1>;
+			clock-names = "ppmu";
+			events {
+				ppmu_event_dmc1_1: ppmu-event3-dmc1_1 {
+					event-name = "ppmu-event3-dmc1_1";
+				};
+			};
+		};
+
 		gsc_pd: power-domain@10044000 {
 			compatible = "samsung,exynos4210-pd";
 			reg = <0x10044000 0x20>;
diff --git a/arch/arm/boot/dts/exynos5422-odroid-core.dtsi b/arch/arm/boot/dts/exynos5422-odroid-core.dtsi
index bf09eab..e2b59e9 100644
--- a/arch/arm/boot/dts/exynos5422-odroid-core.dtsi
+++ b/arch/arm/boot/dts/exynos5422-odroid-core.dtsi
@@ -127,6 +127,12 @@
 	cpu-supply = <&buck2_reg>;
 };
 
+&dmc {
+	devfreq-events = <&ppmu_dmc0_0>, <&ppmu_dmc0_1>,
+			<&ppmu_dmc1_0>, <&ppmu_dmc1_1>;
+	status = "okay";
+};
+
 &hsi2c_4 {
 	status = "okay";
 
@@ -535,6 +541,22 @@
 	};
 };
 
+&ppmu_dmc0_0 {
+	status = "okay";
+};
+
+&ppmu_dmc0_1 {
+	status = "okay";
+};
+
+&ppmu_dmc1_0 {
+	status = "okay";
+};
+
+&ppmu_dmc1_1 {
+	status = "okay";
+};
+
 &tmu_cpu0 {
 	vtmu-supply = <&ldo7_reg>;
 };
-- 
2.7.4


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Re: [PATCH v4 6/8] DT: arm: exynos: add DMC device for exynos5422

[Krzysztof Kozlowski]

On Fri, 1 Feb 2019 at 17:47, Lukasz Luba <l.luba@partner.samsung.com> wrote:
>
> Add description of Dynamic Memory Controller and PPMU counters.
> They are used by exynos5422-dmc driver.
>
> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
> ---
>  arch/arm/boot/dts/exynos5420.dtsi             | 78 +++++++++++++++++++++++++++
>  arch/arm/boot/dts/exynos5422-odroid-core.dtsi | 22 ++++++++
>  2 files changed, 100 insertions(+)

Looks good for me. I will take it after bindings get accepted. It is
getting late in the cycle so it might end up in subsequent merge
window.

The subject prefix should be "ARM: dts: exynos:". If you are going to
send v5, please fix it. Otherwise there is no problem and I can change
it while applying.

Best regards,
Krzysztof

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[PATCH v4 7/8] drivers: devfreq: events: add Exynos PPMU new events

[Lukasz Luba]

Define new performance events supported by Exynos5422 SoC counters.
The counters are built-in in Dynamic Memory Controller and provide
information regarding memory utilization.

Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
---
 drivers/devfreq/event/exynos-ppmu.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/devfreq/event/exynos-ppmu.c b/drivers/devfreq/event/exynos-ppmu.c
index c61de0b..67d6674 100644
--- a/drivers/devfreq/event/exynos-ppmu.c
+++ b/drivers/devfreq/event/exynos-ppmu.c
@@ -89,6 +89,12 @@ static struct __exynos_ppmu_events {
 	PPMU_EVENT(d1-cpu),
 	PPMU_EVENT(d1-general),
 	PPMU_EVENT(d1-rt),
+
+	/* For Exynos5422 SoC */
+	PPMU_EVENT(dmc0_0),
+	PPMU_EVENT(dmc0_1),
+	PPMU_EVENT(dmc1_0),
+	PPMU_EVENT(dmc1_1),
 };
 
 static int exynos_ppmu_find_ppmu_id(struct devfreq_event_dev *edev)
-- 
2.7.4


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[PATCH v4 8/8] ARM: exynos_defconfig: enable DMC driver

[Lukasz Luba]

Enable driver for Dynamic Memory Controller dynamic frequency and
voltage scaling in Exynos5422 SoCs.

Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
---
 arch/arm/configs/exynos_defconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm/configs/exynos_defconfig b/arch/arm/configs/exynos_defconfig
index d635edf..b5dddcc 100644
--- a/arch/arm/configs/exynos_defconfig
+++ b/arch/arm/configs/exynos_defconfig
@@ -291,6 +291,7 @@ CONFIG_DEVFREQ_GOV_PERFORMANCE=y
 CONFIG_DEVFREQ_GOV_POWERSAVE=y
 CONFIG_DEVFREQ_GOV_USERSPACE=y
 CONFIG_ARM_EXYNOS_BUS_DEVFREQ=y
+CONFIG_ARM_EXYNOS5422_DMC_DEVFREQ=y
 CONFIG_DEVFREQ_EVENT_EXYNOS_NOCP=y
 CONFIG_EXYNOS_IOMMU=y
 CONFIG_EXTCON=y
-- 
2.7.4


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Re: [PATCH v4 8/8] ARM: exynos_defconfig: enable DMC driver

[Krzysztof Kozlowski]

On Fri, 1 Feb 2019 at 17:47, Lukasz Luba <l.luba@partner.samsung.com> wrote:
>
> Enable driver for Dynamic Memory Controller dynamic frequency and
> voltage scaling in Exynos5422 SoCs.
>
> Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
> ---
>  arch/arm/configs/exynos_defconfig | 1 +
>  1 file changed, 1 insertion(+)

Looks good for me. I will take it after driver gets accepted. It is
getting late in the cycle so it might end up in subsequent merge
window.

Best regards,
Krzysztof

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