Re: [PATCH v3 5/8] phy: rockchip-usb: expose the phy-internal PLLs

From: Kishon Vijay Abraham I
Date: Tue Dec 15 2015 - 05:54:13 EST


Hi Mike,

On Friday 20 November 2015 02:52 AM, Heiko Stuebner wrote:
> The USB phys on Rockchip SoCs contain their own internal PLLs to create
> the 480MHz needed. Additionally this PLL output is also fed back into the
> core clock-controller as possible source for clocks like the GPU or others.
>
> Until now this was modelled incorrectly with a "virtual" factor clock in
> the clock controller. The one big caveat is that if we turn off the usb phy
> via the siddq signal, all analog components get turned off, including the
> PLLs. It is therefore possible that a source clock gets disabled without
> the clock driver ever knowing, possibly making the system hang.
>
> Therefore register the phy-plls as real clocks that the clock driver can
> then reference again normally, making the clock hirarchy finally reflect
> the actual hardware.
>
> The phy-ops get converted to simply turning that new clock on and off
> which in turn controls the siddq signal of the phy.
>
> Through this the driver gains handling for platform-specific data, to
> handle the phy->clock name association.

Are you okay with this patch/ Can you give your Acked-by?

Thanks
Kishon

>
> Signed-off-by: Heiko Stuebner <heiko@xxxxxxxxx>
> Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
> ---
> .../devicetree/bindings/phy/rockchip-usb-phy.txt | 1 +
> drivers/phy/phy-rockchip-usb.c | 188 ++++++++++++++++++---
> 2 files changed, 162 insertions(+), 27 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/phy/rockchip-usb-phy.txt b/Documentation/devicetree/bindings/phy/rockchip-usb-phy.txt
> index 9b37242..68498d5 100644
> --- a/Documentation/devicetree/bindings/phy/rockchip-usb-phy.txt
> +++ b/Documentation/devicetree/bindings/phy/rockchip-usb-phy.txt
> @@ -24,6 +24,7 @@ required properties:
> Optional Properties:
> - clocks : phandle + clock specifier for the phy clocks
> - clock-names: string, clock name, must be "phyclk"
> +- #clock-cells: for users of the phy-pll, should be 0
>
> Example:
>
> diff --git a/drivers/phy/phy-rockchip-usb.c b/drivers/phy/phy-rockchip-usb.c
> index 16cd533..33a80eb 100644
> --- a/drivers/phy/phy-rockchip-usb.c
> +++ b/drivers/phy/phy-rockchip-usb.c
> @@ -15,12 +15,14 @@
> */
>
> #include <linux/clk.h>
> +#include <linux/clk-provider.h>
> #include <linux/io.h>
> #include <linux/kernel.h>
> #include <linux/module.h>
> #include <linux/mutex.h>
> #include <linux/of.h>
> #include <linux/of_address.h>
> +#include <linux/of_platform.h>
> #include <linux/phy/phy.h>
> #include <linux/platform_device.h>
> #include <linux/regulator/consumer.h>
> @@ -36,15 +38,28 @@
> #define SIDDQ_ON BIT(13)
> #define SIDDQ_OFF (0 << 13)
>
> +struct rockchip_usb_phys {
> + int reg;
> + const char *pll_name;
> +};
> +
> +struct rockchip_usb_phy_pdata {
> + struct rockchip_usb_phys *phys;
> +};
> +
> struct rockchip_usb_phy_base {
> struct device *dev;
> struct regmap *reg_base;
> + const struct rockchip_usb_phy_pdata *pdata;
> };
>
> struct rockchip_usb_phy {
> struct rockchip_usb_phy_base *base;
> + struct device_node *np;
> unsigned int reg_offset;
> struct clk *clk;
> + struct clk *clk480m;
> + struct clk_hw clk480m_hw;
> struct phy *phy;
> };
>
> @@ -55,17 +70,59 @@ static int rockchip_usb_phy_power(struct rockchip_usb_phy *phy,
> SIDDQ_WRITE_ENA | (siddq ? SIDDQ_ON : SIDDQ_OFF));
> }
>
> -static int rockchip_usb_phy_power_off(struct phy *_phy)
> +static unsigned long rockchip_usb_phy480m_recalc_rate(struct clk_hw *hw,
> + unsigned long parent_rate)
> {
> - struct rockchip_usb_phy *phy = phy_get_drvdata(_phy);
> - int ret = 0;
> + return 480000000;
> +}
> +
> +static void rockchip_usb_phy480m_disable(struct clk_hw *hw)
> +{
> + struct rockchip_usb_phy *phy = container_of(hw,
> + struct rockchip_usb_phy,
> + clk480m_hw);
>
> /* Power down usb phy analog blocks by set siddq 1 */
> - ret = rockchip_usb_phy_power(phy, 1);
> - if (ret)
> + rockchip_usb_phy_power(phy, 1);
> +}
> +
> +static int rockchip_usb_phy480m_enable(struct clk_hw *hw)
> +{
> + struct rockchip_usb_phy *phy = container_of(hw,
> + struct rockchip_usb_phy,
> + clk480m_hw);
> +
> + /* Power up usb phy analog blocks by set siddq 0 */
> + return rockchip_usb_phy_power(phy, 0);
> +}
> +
> +static int rockchip_usb_phy480m_is_enabled(struct clk_hw *hw)
> +{
> + struct rockchip_usb_phy *phy = container_of(hw,
> + struct rockchip_usb_phy,
> + clk480m_hw);
> + int ret;
> + u32 val;
> +
> + ret = regmap_read(phy->base->reg_base, phy->reg_offset, &val);
> + if (ret < 0)
> return ret;
>
> - clk_disable_unprepare(phy->clk);
> + return (val & SIDDQ_ON) ? 0 : 1;
> +}
> +
> +static const struct clk_ops rockchip_usb_phy480m_ops = {
> + .enable = rockchip_usb_phy480m_enable,
> + .disable = rockchip_usb_phy480m_disable,
> + .is_enabled = rockchip_usb_phy480m_is_enabled,
> + .recalc_rate = rockchip_usb_phy480m_recalc_rate,
> +};
> +
> +static int rockchip_usb_phy_power_off(struct phy *_phy)
> +{
> + struct rockchip_usb_phy *phy = phy_get_drvdata(_phy);
> +
> + clk_disable_unprepare(phy->clk480m);
>
> return 0;
> }
> @@ -73,20 +130,8 @@ static int rockchip_usb_phy_power_off(struct phy *_phy)
> static int rockchip_usb_phy_power_on(struct phy *_phy)
> {
> struct rockchip_usb_phy *phy = phy_get_drvdata(_phy);
> - int ret = 0;
>
> - ret = clk_prepare_enable(phy->clk);
> - if (ret)
> - return ret;
> -
> - /* Power up usb phy analog blocks by set siddq 0 */
> - ret = rockchip_usb_phy_power(phy, 0);
> - if (ret) {
> - clk_disable_unprepare(phy->clk);
> - return ret;
> - }
> -
> - return 0;
> + return clk_prepare_enable(phy->clk480m);
> }
>
> static const struct phy_ops ops = {
> @@ -99,6 +144,9 @@ static void rockchip_usb_phy_action(void *data)
> {
> struct rockchip_usb_phy *rk_phy = data;
>
> + of_clk_del_provider(rk_phy->np);
> + clk_unregister(rk_phy->clk480m);
> +
> if (rk_phy->clk)
> clk_put(rk_phy->clk);
> }
> @@ -108,13 +156,16 @@ static int rockchip_usb_phy_init(struct rockchip_usb_phy_base *base,
> {
> struct rockchip_usb_phy *rk_phy;
> unsigned int reg_offset;
> - int err;
> + const char *clk_name;
> + struct clk_init_data init;
> + int err, i;
>
> rk_phy = devm_kzalloc(base->dev, sizeof(*rk_phy), GFP_KERNEL);
> if (!rk_phy)
> return -ENOMEM;
>
> rk_phy->base = base;
> + rk_phy->np = child;
>
> if (of_property_read_u32(child, "reg", &reg_offset)) {
> dev_err(base->dev, "missing reg property in node %s\n",
> @@ -124,14 +175,54 @@ static int rockchip_usb_phy_init(struct rockchip_usb_phy_base *base,
>
> rk_phy->reg_offset = reg_offset;
>
> - err = devm_add_action(base->dev, rockchip_usb_phy_action, rk_phy);
> - if (err)
> - return err;
> -
> rk_phy->clk = of_clk_get_by_name(child, "phyclk");
> if (IS_ERR(rk_phy->clk))
> rk_phy->clk = NULL;
>
> + i = 0;
> + init.name = NULL;
> + while (base->pdata->phys[i].reg) {
> + if (base->pdata->phys[i].reg == reg_offset) {
> + init.name = base->pdata->phys[i].pll_name;
> + break;
> + }
> + i++;
> + }
> +
> + if (!init.name) {
> + dev_err(base->dev, "phy data not found\n");
> + return -EINVAL;
> + }
> +
> + if (rk_phy->clk) {
> + clk_name = __clk_get_name(rk_phy->clk);
> + init.flags = 0;
> + init.parent_names = &clk_name;
> + init.num_parents = 1;
> + } else {
> + init.flags = CLK_IS_ROOT;
> + init.parent_names = NULL;
> + init.num_parents = 0;
> + }
> +
> + init.ops = &rockchip_usb_phy480m_ops;
> + rk_phy->clk480m_hw.init = &init;
> +
> + rk_phy->clk480m = clk_register(base->dev, &rk_phy->clk480m_hw);
> + if (IS_ERR(rk_phy->clk480m)) {
> + err = PTR_ERR(rk_phy->clk480m);
> + goto err_clk;
> + }
> +
> + err = of_clk_add_provider(child, of_clk_src_simple_get,
> + rk_phy->clk480m);
> + if (err < 0)
> + goto err_clk_prov;
> +
> + err = devm_add_action(base->dev, rockchip_usb_phy_action, rk_phy);
> + if (err)
> + goto err_devm_action;
> +
> rk_phy->phy = devm_phy_create(base->dev, child, &ops);
> if (IS_ERR(rk_phy->phy)) {
> dev_err(base->dev, "failed to create PHY\n");
> @@ -141,13 +232,48 @@ static int rockchip_usb_phy_init(struct rockchip_usb_phy_base *base,
>
> /* only power up usb phy when it use, so disable it when init*/
> return rockchip_usb_phy_power(rk_phy, 1);
> +
> +err_devm_action:
> + of_clk_del_provider(child);
> +err_clk_prov:
> + clk_unregister(rk_phy->clk480m);
> +err_clk:
> + if (rk_phy->clk)
> + clk_put(rk_phy->clk);
> + return err;
> }
>
> +static const struct rockchip_usb_phy_pdata rk3066a_pdata = {
> + .phys = (struct rockchip_usb_phys[]){
> + { .reg = 0x17c, .pll_name = "sclk_otgphy0_480m" },
> + { .reg = 0x188, .pll_name = "sclk_otgphy1_480m" },
> + { /* sentinel */ }
> + },
> +};
> +
> +static const struct rockchip_usb_phy_pdata rk3188_pdata = {
> + .phys = (struct rockchip_usb_phys[]){
> + { .reg = 0x10c, .pll_name = "sclk_otgphy0_480m" },
> + { .reg = 0x11c, .pll_name = "sclk_otgphy1_480m" },
> + { /* sentinel */ }
> + },
> +};
> +
> +static const struct rockchip_usb_phy_pdata rk3288_pdata = {
> + .phys = (struct rockchip_usb_phys[]){
> + { .reg = 0x320, .pll_name = "sclk_otgphy0_480m" },
> + { .reg = 0x334, .pll_name = "sclk_otgphy1_480m" },
> + { .reg = 0x348, .pll_name = "sclk_otgphy2_480m" },
> + { /* sentinel */ }
> + },
> +};
> +
> static int rockchip_usb_phy_probe(struct platform_device *pdev)
> {
> struct device *dev = &pdev->dev;
> struct rockchip_usb_phy_base *phy_base;
> struct phy_provider *phy_provider;
> + const struct of_device_id *match;
> struct device_node *child;
> int err;
>
> @@ -155,6 +281,14 @@ static int rockchip_usb_phy_probe(struct platform_device *pdev)
> if (!phy_base)
> return -ENOMEM;
>
> + match = of_match_device(dev->driver->of_match_table, dev);
> + if (!match || !match->data) {
> + dev_err(dev, "missing phy data\n");
> + return -EINVAL;
> + }
> +
> + phy_base->pdata = match->data;
> +
> phy_base->dev = dev;
> phy_base->reg_base = syscon_regmap_lookup_by_phandle(dev->of_node,
> "rockchip,grf");
> @@ -176,9 +310,9 @@ static int rockchip_usb_phy_probe(struct platform_device *pdev)
> }
>
> static const struct of_device_id rockchip_usb_phy_dt_ids[] = {
> - { .compatible = "rockchip,rk3066a-usb-phy" },
> - { .compatible = "rockchip,rk3188-usb-phy" },
> - { .compatible = "rockchip,rk3288-usb-phy" },
> + { .compatible = "rockchip,rk3066a-usb-phy", .data = &rk3066a_pdata },
> + { .compatible = "rockchip,rk3188-usb-phy", .data = &rk3188_pdata },
> + { .compatible = "rockchip,rk3288-usb-phy", .data = &rk3288_pdata },
> {}
> };
>
>
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