[linux-sunxi] Re: [PATCH 2/4] clk: sunxi-ng: Add sun7i-a20 CCU driver
Priit Laes
plaes at plaes.org
Wed Mar 1 13:38:14 PST 2017
On Tue, 2017-02-28 at 09:21 +0100, Maxime Ripard wrote:
> Hi,
>
> On Mon, Feb 27, 2017 at 11:09:12PM +0200, Priit Laes wrote:
> > Introduce a clock controller driver for sun7i A20 SoC.
> >
> > > > Signed-off-by: Priit Laes <plaes at plaes.org>
> > ---
> > drivers/clk/sunxi-ng/Kconfig | 11 +
> > drivers/clk/sunxi-ng/Makefile | 1 +
> > drivers/clk/sunxi-ng/ccu-sun7i-a20.c | 1068 ++++++++++++++++++++++++++++++++++
> > drivers/clk/sunxi-ng/ccu-sun7i-a20.h | 121 ++++
> > 4 files changed, 1201 insertions(+)
> > create mode 100644 drivers/clk/sunxi-ng/ccu-sun7i-a20.c
> > create mode 100644 drivers/clk/sunxi-ng/ccu-sun7i-a20.h
> >
> > diff --git a/drivers/clk/sunxi-ng/Kconfig b/drivers/clk/sunxi-ng/Kconfig
> > index 695bbf9..4f436ab 100644
> > --- a/drivers/clk/sunxi-ng/Kconfig
> > +++ b/drivers/clk/sunxi-ng/Kconfig
> > @@ -85,6 +85,17 @@ config SUN6I_A31_CCU
> > > > select SUNXI_CCU_PHASE
> > > > default MACH_SUN6I
> >
> > +config SUN7I_A20_CCU
> > > > + bool "Support for the Allwinner A20 CCU"
> > > > + select SUNXI_CCU_DIV
> > > > + select SUNXI_CCU_MULT
> > > > + select SUNXI_CCU_NK
> > > > + select SUNXI_CCU_NKM
> > > > + select SUNXI_CCU_NM
> > > > + select SUNXI_CCU_MP
> > > > + select SUNXI_CCU_PHASE
> > > > + default MACH_SUN7I
> > +
> > config SUN8I_A23_CCU
> > > > bool "Support for the Allwinner A23 CCU"
> > > > select SUNXI_CCU_DIV
> > diff --git a/drivers/clk/sunxi-ng/Makefile b/drivers/clk/sunxi-ng/Makefile
> > index 6feaac0..bedda5b 100644
> > --- a/drivers/clk/sunxi-ng/Makefile
> > +++ b/drivers/clk/sunxi-ng/Makefile
> > > > @@ -21,6 +21,7 @@ obj-$(CONFIG_SUNXI_CCU_MP) += ccu_mp.o
> > > > obj-$(CONFIG_SUN50I_A64_CCU) += ccu-sun50i-a64.o
> > > > obj-$(CONFIG_SUN5I_CCU) += ccu-sun5i.o
> > > > obj-$(CONFIG_SUN6I_A31_CCU) += ccu-sun6i-a31.o
> > > > +obj-$(CONFIG_SUN7I_A20_CCU) += ccu-sun7i-a20.o
> > > > obj-$(CONFIG_SUN8I_A23_CCU) += ccu-sun8i-a23.o
> > > > obj-$(CONFIG_SUN8I_A33_CCU) += ccu-sun8i-a33.o
> > > > obj-$(CONFIG_SUN8I_H3_CCU) += ccu-sun8i-h3.o
> > diff --git a/drivers/clk/sunxi-ng/ccu-sun7i-a20.c b/drivers/clk/sunxi-ng/ccu-sun7i-a20.c
> > new file mode 100644
> > index 0000000..90d2f13
> > --- /dev/null
> > +++ b/drivers/clk/sunxi-ng/ccu-sun7i-a20.c
> > @@ -0,0 +1,1068 @@
> > +/*
> > + * Copyright (c) 2017 Priit Laes. All rights reserved.
> > + *
> > + * This software is licensed under the terms of the GNU General Public
> > + * License version 2, as published by the Free Software Foundation, and
> > + * may be copied, distributed, and modified under those terms.
> > + *
> > + * This program is distributed in the hope that it will be useful,
> > + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> > + * GNU General Public License for more details.
> > + */
> > +
> > +#include <linux/clk-provider.h>
> > +#include <linux/of_address.h>
> > +
> > +#include "ccu_common.h"
> > +#include "ccu_reset.h"
> > +
> > +#include "ccu_div.h"
> > +#include "ccu_gate.h"
> > +#include "ccu_mp.h"
> > +#include "ccu_mult.h"
> > +#include "ccu_nk.h"
> > +#include "ccu_nkm.h"
> > +#include "ccu_nkmp.h"
> > +#include "ccu_nm.h"
> > +#include "ccu_phase.h"
> > +
> > +#include "ccu-sun7i-a20.h"
> > +
> > +/*
> > + * PLL1 - Core clock
> > + *
> > + * TODO: sigma-delta pattern bits 2 & 3
> > + * TODO: PLL1 tuning register
>
> I don't think we need those TODO's at all, and these comments too. If
> the clock name is good enough (and it is), it's redundant.
Ok, will clean them up.
>
> > + */
> >
[...]
> > +};
> > +
> > +/* PLL2 - Audio clock */
> > +static struct ccu_nm pll_audio_base_clk = {
> > > > > > + .enable = BIT(31),
> > > > > > + .n = _SUNXI_CCU_MULT_OFFSET(8, 7, 0),
> > > > > > + .m = _SUNXI_CCU_DIV_OFFSET(0, 5, 0),
> > > > > > + .common = {
> > > > > > + .reg = 0x008,
> > > > > > + .hw.init = CLK_HW_INIT("pll-audio-base",
> > > > + "hosc",
> > > > + &ccu_nm_ops,
> > > > + 0),
> > > > + },
> > +
> > +};
>
> You're forgetting the post-divider here
It's hardcoded to 4 during ccu initialization, similar to what is done
on the other SoCs (A13, A31..).
>
> > +/* TODO: pll8 gpu 0x040 */
>
> Please add all the clocks.
I'm not really comfortable adding clocks for blocks that currently lack
drivers.
> > +/* BIT(21 .. 31) - reserved */
>
> I'm not sure we need those comments either.
>
> > +/*
> > + * TODO: SATA clock also supports external clock as parent.
> > + * Currently we default to using PLL6 SATA gate.
> > + */
>
> Which external clock? It should be modelled anyway. If we have a
> dependency on some other clock, it should be in our DT binding, and
> listed in the mux there.
>
> Otherwise, the clock framework will not be able to deal with that mux
> being already set by the bootloader, and if we need to support that
> clock in the future, our binding will be ready for it.
I wish I knew which clock they're talking about..
User manuals (A10/A20) only specify following in the clock register
description:
BIT(24) - CLK_SRC_GATING, default 0x0
Clock Source Select:
0: PLL6 for SATA(100MHz)
1: External Clock
There's no section for SATA (called NC) in A10 manual, and in A20
manual only contains list of SATA/AHCI features.
>
> > +static CLK_FIXED_FACTOR(pll_periph_2x_clk, "pll-periph-2x",
> > > > + "pll-periph", 1, 2, CLK_SET_RATE_PARENT);
> > +/* We hardcode the divider to 4 for now */
> > +static CLK_FIXED_FACTOR(pll_audio_clk, "pll-audio",
> > > > + "pll-audio-base", 4, 1, CLK_SET_RATE_PARENT);
> > +static CLK_FIXED_FACTOR(pll_audio_2x_clk, "pll-audio-2x",
> > > > + "pll-audio-base", 2, 1, CLK_SET_RATE_PARENT);
> > +static CLK_FIXED_FACTOR(pll_audio_4x_clk, "pll-audio-4x",
> > > > + "pll-audio-base", 1, 1, CLK_SET_RATE_PARENT);
> > +static CLK_FIXED_FACTOR(pll_audio_8x_clk, "pll-audio-8x",
> > > > + "pll-audio-base", 1, 2, CLK_SET_RATE_PARENT);
> > +static CLK_FIXED_FACTOR(pll_video0_2x_clk, "pll-video0-2x",
> > > > + "pll-video0", 1, 2, CLK_SET_RATE_PARENT);
> > +static CLK_FIXED_FACTOR(pll_video1_2x_clk, "pll-video1-2x",
> > + "pll-video1", 1, 2, CLK_SET_RATE_PARENT);
>
> It feels more natural to just have the clocks defined in the same
> order than their parents. So periph shouldn't be first
Ok, will move the periph clock after the video.
> > +static struct ccu_reset_map sun7i_a20_ccu_resets[] = {
> > +
> > > > > > + [RST_USB_PHY0] = { 0x0cc, BIT(0) },
> > > > > > + [RST_USB_PHY1] = { 0x0cc, BIT(1) },
> > > > > > + [RST_USB_PHY2] = { 0x0cc, BIT(2) },
> > > > > > + [RST_DE_BE0] = { 0x104, BIT(30) },
> > > > > > + [RST_DE_BE1] = { 0x108, BIT(30) },
> > > > > > + [RST_DE_FE0] = { 0x10c, BIT(30) },
> > > > > > + [RST_DE_FE1] = { 0x110, BIT(30) },
> > > > > > + [RST_DE_MP] = { 0x114, BIT(30) },
> > > > > > + [RST_TCON0] = { 0x118, BIT(30) },
> > > > > > + [RST_TCON1] = { 0x11c, BIT(30) },
> > > > > > + [RST_CSI0] = { 0x134, BIT(30) },
> > > > > > + [RST_CSI1] = { 0x138, BIT(30) },
> > > > > > + [RST_VE] = { 0x13c, BIT(0) },
> > > > > > + [RST_ACE] = { 0x148, BIT(16) },
> > > > > > + [RST_LVDS] = { 0x14c, BIT(0) },
> > > > > > + [RST_GPU] = { 0x154, BIT(30) },
> > > > > > + [RST_HDMI_H] = { 0x170, BIT(0) },
> > > > > > + [RST_HDMI_SYS] = { 0x170, BIT(1) },
> > > > > > + [RST_HDMI_AUDIO_DMA] = { 0x170, BIT(2) },
> > +};
> > +
> > +static const struct sunxi_ccu_desc sun7i_a20_ccu_desc = {
> > > > > > + .ccu_clks = sun7i_a20_ccu_clks,
> > > > > > + .num_ccu_clks = ARRAY_SIZE(sun7i_a20_ccu_clks),
> > +
> > > > > > + .hw_clks = &sun7i_a20_hw_clks,
> > +
> > > > > > + .resets = sun7i_a20_ccu_resets,
> > > > > > + .num_resets = ARRAY_SIZE(sun7i_a20_ccu_resets),
> > +};
> > +
> > +static void __init sun7i_a20_ccu_setup(struct device_node *node)
> > +{
> > > > + void __iomem *reg;
> > > > + u32 val;
> > +
> > > > + reg = of_io_request_and_map(node, 0, of_node_full_name(node));
> > > > + if (IS_ERR(reg)) {
> > > > + pr_err("%s: Could not map the clock registers\n",
> > > > + of_node_full_name(node));
> > > > + return;
> > > > + }
> > +
> > + #define SUN7I_PLL_AUDIO_REG 0x008
>
> This should be defined above
Will do..
>
> > +
> > > > + /* Force the PLL-Audio-1x divider to 4 */
> > > > + val = readl(reg + SUN7I_PLL_AUDIO_REG);
> > > > + val &= ~GENMASK(19, 16);
> > > > + writel(val | (3 << 16), reg + SUN7I_PLL_AUDIO_REG);
> > +
> > > > + /*
> > > > + * Use PLL6 as parent for AHB
> > + * CPU/AXI clock changes rate when cpufreq is enabled
>
> I'm not sure why that last sentence is needed too. A lot of clock
> listed there change rate when <some-feature> is enabled.
Will remove.
>
> > +/* Some AHB gates are exported */
> > > > +#define CLK_AHB_BIST 31
> > > > +#define CLK_AHB_MS 36
> > > > +#define CLK_AHB_SDRAM 38
> > > > +#define CLK_AHB_ACE 39
> > > > +#define CLK_AHB_TS 41
> > > > +#define CLK_AHB_VE 48
> > > > +#define CLK_AHB_TVD 49
> > > > +#define CLK_AHB_TVE1 51
> > > > +#define CLK_AHB_LCD1 53
> > > > +#define CLK_AHB_CSI0 54
> > > > +#define CLK_AHB_CSI1 55
> > > > +#define CLK_AHB_HDMI0 56
> > > > +#define CLK_AHB_DE_BE1 59
> > > > +#define CLK_AHB_DE_FE0 60
> > > > +#define CLK_AHB_DE_FE1 61
> > > > +#define CLK_AHB_MP 63
> > > > +#define CLK_AHB_GPU 64
> > +
> > +/* Some APB0 gates are exported */
> > > > +#define CLK_APB0_AC97 67
> > > > +#define CLK_APB0_KEYPAD 74
> > +
> > +/* Some APB1 gates are exported */
> > > > +#define CLK_APB1_CAN 79
> > > > +#define CLK_APB1_SCR 80
> > +
> > +/* Some IP module clocks are exported */
> > > > +#define CLK_MS 93
> > > > +#define CLK_TS 106
> > > > +#define CLK_PATA 111
> > > > +#define CLK_AC97 115
> > > > +#define CLK_KEYPAD 117
> > > > +#define CLK_SATA 118
> > +
> > +/* Some DRAM gates are exported */
> > > > +#define CLK_DRAM_VE 125
> > > > +#define CLK_DRAM_CSI0 126
> > > > +#define CLK_DRAM_CSI1 127
> > > > +#define CLK_DRAM_TS 128
> > > > +#define CLK_DRAM_TVD 129
> > > > +#define CLK_DRAM_TVE1 131
> > > > +#define CLK_DRAM_OUT 132
> > > > +#define CLK_DRAM_DE_FE1 133
> > > > +#define CLK_DRAM_DE_FE0 134
> > > > +#define CLK_DRAM_DE_BE1 136
> > > > +#define CLK_DRAM_MP 137
> > > > +#define CLK_DRAM_ACE 138
> > +
> > > > +#define CLK_DE_BE1 140
> > > > +#define CLK_DE_FE0 141
> > > > +#define CLK_DE_FE1 142
> > > > +#define CLK_DE_MP 143
> > > > +#define CLK_TCON1_CH0 145
> > > > +#define CLK_CSI_SPECIAL 146
> > > > +#define CLK_TVD 147
> > > > +#define CLK_TCON0_CH1_SCLK2 148
> > > > +#define CLK_TCON1_CH1_SCLK2 150
> > > > +#define CLK_TCON1_CH1 151
> > > > +#define CLK_CSI0 152
> > > > +#define CLK_CSI1 153
> > > > +#define CLK_VE 154
> > > > +#define CLK_AVS 156
> > > > +#define CLK_ACE 157
> > > > +#define CLK_HDMI 158
> > > > +#define CLK_GPU 159
> > > > +#define CLK_MBUS 160
> > > > +#define CLK_HDMI1_SLOW 161
> > > > +#define CLK_HDMI1_REPEAT 162
> > > > +#define CLK_OUT_A 163
> > +#define CLK_OUT_B 164
>
> Is there a reason not to expose these clocks?
I exposed them on need to have basis. And basically did one-to-one
conversion from devicetree.
Päikest,
Priit
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