| Message ID | 1559084936-4610-4-git-send-email-skomatineni@nvidia.com |
|---|---|
| State | New |
| Headers | show |
| Series | LP0 entry and exit support for Tegra210 | expand |
Quoting Sowjanya Komatineni (2019-05-28 16:08:47) > This patch has implementation of saving and restoring PLL's state to > support system suspend and resume operations. Can you provide some more background on _why_ this patch should exist? That's typically what gets written in the commit text. > > Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com> > --- > drivers/clk/tegra/clk-divider.c | 19 ++++++++ > drivers/clk/tegra/clk-pll-out.c | 25 +++++++++++ > drivers/clk/tegra/clk-pll.c | 99 ++++++++++++++++++++++++++++++++--------- > drivers/clk/tegra/clk.h | 9 ++++ > 4 files changed, 132 insertions(+), 20 deletions(-) > > diff --git a/drivers/clk/tegra/clk-divider.c b/drivers/clk/tegra/clk-divider.c > index 2a1822a22740..718694727042 100644 > --- a/drivers/clk/tegra/clk-divider.c > +++ b/drivers/clk/tegra/clk-divider.c > @@ -14,6 +14,7 @@ > * along with this program. If not, see <http://www.gnu.org/licenses/>. > */ > > +#include <linux/clk.h> > #include <linux/kernel.h> > #include <linux/io.h> > #include <linux/err.h> > @@ -179,3 +180,21 @@ struct clk *tegra_clk_register_mc(const char *name, const char *parent_name, > reg, 16, 1, CLK_DIVIDER_READ_ONLY, > mc_div_table, lock); > } > + > +#if defined(CONFIG_PM_SLEEP) > +void tegra_clk_divider_resume(struct clk_hw *hw, unsigned long rate) > +{ > + struct clk_hw *parent = clk_hw_get_parent(hw); > + unsigned long parent_rate; > + > + if (IS_ERR(parent)) { Will this ever happen? Collapse the WARN_ON into the if please: if (WARN_ON(IS_ERR(parent))) > + WARN_ON(1); > + return; > + } > + > + parent_rate = clk_hw_get_rate(parent); > + > + if (clk_frac_div_set_rate(hw, rate, parent_rate) < 0) > + WARN_ON(1); > +} > +#endif > diff --git a/drivers/clk/tegra/clk.h b/drivers/clk/tegra/clk.h > index 09bccbb9640c..e4d124cc5657 100644 > --- a/drivers/clk/tegra/clk.h > +++ b/drivers/clk/tegra/clk.h > @@ -841,6 +841,15 @@ int tegra_pll_p_div_to_hw(struct tegra_clk_pll *pll, u8 p_div); > int div_frac_get(unsigned long rate, unsigned parent_rate, u8 width, > u8 frac_width, u8 flags); > > +#ifdef CONFIG_PM_SLEEP Can you remove this ifdef? It just complicates compilation testing. > +void tegra_clk_pll_resume(struct clk *c, unsigned long rate); > +void tegra_clk_divider_resume(struct clk_hw *hw, unsigned long rate); > +void tegra_clk_pll_out_resume(struct clk *clk, unsigned long rate); > +void tegra_clk_plle_tegra210_resume(struct clk *c); > +void tegra_clk_sync_state_pll(struct clk *c); > +void tegra_clk_sync_state_pll_out(struct clk *clk); Do these APIs need to operate on struct clk? Why can't they operate on clk_hw or why can't we drive the suspend/resume sequence from the clk provider driver itself?
On 5/29/19 4:28 PM, Stephen Boyd wrote: > Quoting Sowjanya Komatineni (2019-05-28 16:08:47) >> This patch has implementation of saving and restoring PLL's state to >> support system suspend and resume operations. > Can you provide some more background on _why_ this patch should exist? > That's typically what gets written in the commit text. Will add more in next version of this series. >> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com> >> --- >> drivers/clk/tegra/clk-divider.c | 19 ++++++++ >> drivers/clk/tegra/clk-pll-out.c | 25 +++++++++++ >> drivers/clk/tegra/clk-pll.c | 99 ++++++++++++++++++++++++++++++++--------- >> drivers/clk/tegra/clk.h | 9 ++++ >> 4 files changed, 132 insertions(+), 20 deletions(-) >> >> diff --git a/drivers/clk/tegra/clk-divider.c b/drivers/clk/tegra/clk-divider.c >> index 2a1822a22740..718694727042 100644 >> --- a/drivers/clk/tegra/clk-divider.c >> +++ b/drivers/clk/tegra/clk-divider.c >> @@ -14,6 +14,7 @@ >> * along with this program. If not, see <http://www.gnu.org/licenses/>. >> */ >> >> +#include <linux/clk.h> >> #include <linux/kernel.h> >> #include <linux/io.h> >> #include <linux/err.h> >> @@ -179,3 +180,21 @@ struct clk *tegra_clk_register_mc(const char *name, const char *parent_name, >> reg, 16, 1, CLK_DIVIDER_READ_ONLY, >> mc_div_table, lock); >> } >> + >> +#if defined(CONFIG_PM_SLEEP) >> +void tegra_clk_divider_resume(struct clk_hw *hw, unsigned long rate) >> +{ >> + struct clk_hw *parent = clk_hw_get_parent(hw); >> + unsigned long parent_rate; >> + >> + if (IS_ERR(parent)) { > Will this ever happen? Collapse the WARN_ON into the if please: > > if (WARN_ON(IS_ERR(parent))) > Will fix in next version of this series. >> + WARN_ON(1); >> + return; >> + } >> + >> + parent_rate = clk_hw_get_rate(parent); >> + >> + if (clk_frac_div_set_rate(hw, rate, parent_rate) < 0) >> + WARN_ON(1); >> +} >> +#endif >> diff --git a/drivers/clk/tegra/clk.h b/drivers/clk/tegra/clk.h >> index 09bccbb9640c..e4d124cc5657 100644 >> --- a/drivers/clk/tegra/clk.h >> +++ b/drivers/clk/tegra/clk.h >> @@ -841,6 +841,15 @@ int tegra_pll_p_div_to_hw(struct tegra_clk_pll *pll, u8 p_div); >> int div_frac_get(unsigned long rate, unsigned parent_rate, u8 width, >> u8 frac_width, u8 flags); >> >> +#ifdef CONFIG_PM_SLEEP > Can you remove this ifdef? It just complicates compilation testing. OK, Will fix in next version >> +void tegra_clk_pll_resume(struct clk *c, unsigned long rate); >> +void tegra_clk_divider_resume(struct clk_hw *hw, unsigned long rate); >> +void tegra_clk_pll_out_resume(struct clk *clk, unsigned long rate); >> +void tegra_clk_plle_tegra210_resume(struct clk *c); >> +void tegra_clk_sync_state_pll(struct clk *c); >> +void tegra_clk_sync_state_pll_out(struct clk *clk); > Do these APIs need to operate on struct clk? Why can't they operate on > clk_hw or why can't we drive the suspend/resume sequence from the clk > provider driver itself? > Yes can change to use clk_hw. By clk provider driver, are you referring to clk-tegra210? clk-terga210 driver has suspend/resume implementation. These API's are for corresponding clock specific implementations (clk-pll, clk-pll-out, clk-divider) for enabling and restoring to proper rate and are invoked during clk-tegra210 driver resume. thanks Sowjanya
Quoting Sowjanya Komatineni (2019-05-31 12:52:44) > > On 5/29/19 4:28 PM, Stephen Boyd wrote: > > Quoting Sowjanya Komatineni (2019-05-28 16:08:47) > >> + WARN_ON(1); > >> + return; > >> + } > >> + > >> + parent_rate = clk_hw_get_rate(parent); > >> + > >> + if (clk_frac_div_set_rate(hw, rate, parent_rate) < 0) > >> + WARN_ON(1); > >> +} > >> +#endif > >> diff --git a/drivers/clk/tegra/clk.h b/drivers/clk/tegra/clk.h > >> index 09bccbb9640c..e4d124cc5657 100644 > >> --- a/drivers/clk/tegra/clk.h > >> +++ b/drivers/clk/tegra/clk.h > >> @@ -841,6 +841,15 @@ int tegra_pll_p_div_to_hw(struct tegra_clk_pll *pll, u8 p_div); > >> int div_frac_get(unsigned long rate, unsigned parent_rate, u8 width, > >> u8 frac_width, u8 flags); > >> > >> +#ifdef CONFIG_PM_SLEEP > > Can you remove this ifdef? It just complicates compilation testing. > OK, Will fix in next version > >> +void tegra_clk_pll_resume(struct clk *c, unsigned long rate); > >> +void tegra_clk_divider_resume(struct clk_hw *hw, unsigned long rate); > >> +void tegra_clk_pll_out_resume(struct clk *clk, unsigned long rate); > >> +void tegra_clk_plle_tegra210_resume(struct clk *c); > >> +void tegra_clk_sync_state_pll(struct clk *c); > >> +void tegra_clk_sync_state_pll_out(struct clk *clk); > > Do these APIs need to operate on struct clk? Why can't they operate on > > clk_hw or why can't we drive the suspend/resume sequence from the clk > > provider driver itself? > > > Yes can change to use clk_hw. > > By clk provider driver, are you referring to clk-tegra210? I guess so. > > clk-terga210 driver has suspend/resume implementation. These API's are > for corresponding clock specific implementations (clk-pll, clk-pll-out, > clk-divider) for enabling and restoring to proper rate and are invoked > during clk-tegra210 driver resume. Yes, so when the clk provider suspends it needs to do something? Our handling of clk rates and other state like enable/disable over suspend/resume isn't really well thought out or implemented so far. TI has some code to do some stuff, but otherwise I haven't seen drivers handling this. Ideally it would be something generic in the framework so that drivers don't have to work around stuff.
diff --git a/drivers/clk/tegra/clk-divider.c b/drivers/clk/tegra/clk-divider.c index 2a1822a22740..718694727042 100644 --- a/drivers/clk/tegra/clk-divider.c +++ b/drivers/clk/tegra/clk-divider.c @@ -14,6 +14,7 @@ * along with this program. If not, see <http://www.gnu.org/licenses/>. */ +#include <linux/clk.h> #include <linux/kernel.h> #include <linux/io.h> #include <linux/err.h> @@ -179,3 +180,21 @@ struct clk *tegra_clk_register_mc(const char *name, const char *parent_name, reg, 16, 1, CLK_DIVIDER_READ_ONLY, mc_div_table, lock); } + +#if defined(CONFIG_PM_SLEEP) +void tegra_clk_divider_resume(struct clk_hw *hw, unsigned long rate) +{ + struct clk_hw *parent = clk_hw_get_parent(hw); + unsigned long parent_rate; + + if (IS_ERR(parent)) { + WARN_ON(1); + return; + } + + parent_rate = clk_hw_get_rate(parent); + + if (clk_frac_div_set_rate(hw, rate, parent_rate) < 0) + WARN_ON(1); +} +#endif diff --git a/drivers/clk/tegra/clk-pll-out.c b/drivers/clk/tegra/clk-pll-out.c index 257cae0c1488..8b8c3b77d243 100644 --- a/drivers/clk/tegra/clk-pll-out.c +++ b/drivers/clk/tegra/clk-pll-out.c @@ -14,6 +14,7 @@ * along with this program. If not, see <http://www.gnu.org/licenses/>. */ +#include <linux/clk.h> #include <linux/kernel.h> #include <linux/io.h> #include <linux/err.h> @@ -120,3 +121,27 @@ struct clk *tegra_clk_register_pll_out(const char *name, return clk; } + +#if defined(CONFIG_PM_SLEEP) +void tegra_clk_pll_out_resume(struct clk *clk, unsigned long rate) +{ + struct clk_hw *hw = __clk_get_hw(clk); + struct clk_hw *parent = clk_hw_get_parent(hw); + + if (IS_ERR(parent)) { + WARN_ON(1); + return; + } + + tegra_clk_divider_resume(parent, rate); + clk_pll_out_enable(hw); +} + +void tegra_clk_sync_state_pll_out(struct clk *clk) +{ + struct clk_hw *hw = __clk_get_hw(clk); + + if (!__clk_get_enable_count(clk)) + clk_pll_out_disable(hw); +} +#endif diff --git a/drivers/clk/tegra/clk-pll.c b/drivers/clk/tegra/clk-pll.c index 6b976b2514f7..b363b6c6f600 100644 --- a/drivers/clk/tegra/clk-pll.c +++ b/drivers/clk/tegra/clk-pll.c @@ -20,6 +20,7 @@ #include <linux/err.h> #include <linux/clk.h> #include <linux/clk-provider.h> +#include <linux/clk/tegra.h> #include "clk.h" @@ -1813,6 +1814,28 @@ static int clk_pllu_tegra114_enable(struct clk_hw *hw) return ret; } + +static void _clk_plle_tegra_init_parent(struct tegra_clk_pll *pll) +{ + u32 val, val_aux; + + /* ensure parent is set to pll_ref */ + + val = pll_readl_base(pll); + val_aux = pll_readl(pll->params->aux_reg, pll); + + if (val & PLL_BASE_ENABLE) { + if ((val_aux & PLLE_AUX_PLLRE_SEL) || + (val_aux & PLLE_AUX_PLLP_SEL)) + WARN(1, "pll_e enabled with unsupported parent %s\n", + (val_aux & PLLE_AUX_PLLP_SEL) ? "pllp_out0" : + "pll_re_vco"); + } else { + val_aux &= ~(PLLE_AUX_PLLRE_SEL | PLLE_AUX_PLLP_SEL); + pll_writel(val_aux, pll->params->aux_reg, pll); + fence_udelay(1, pll->clk_base); + } +} #endif static struct tegra_clk_pll *_tegra_init_pll(void __iomem *clk_base, @@ -2289,6 +2312,21 @@ static const struct clk_ops tegra_clk_pllss_ops = { .set_rate = clk_pllxc_set_rate, }; +static void _pllss_set_defaults(struct tegra_clk_pll *pll) +{ + u32 val; + + pll_writel_misc(PLLSS_MISC_DEFAULT, pll); + pll_writel(PLLSS_CFG_DEFAULT, pll->params->ext_misc_reg[0], pll); + pll_writel(PLLSS_CTRL1_DEFAULT, pll->params->ext_misc_reg[1], pll); + pll_writel(PLLSS_CTRL2_DEFAULT, pll->params->ext_misc_reg[2], pll); + + val = pll_readl_base(pll); + val &= ~PLLSS_LOCK_OVERRIDE; + pll_writel_base(val, pll); +} + struct clk *tegra_clk_register_pllss(const char *name, const char *parent_name, void __iomem *clk_base, unsigned long flags, struct tegra_clk_pll_params *pll_params, @@ -2339,10 +2377,7 @@ struct clk *tegra_clk_register_pllss(const char *name, const char *parent_name, _update_pll_mnp(pll, &cfg); - pll_writel_misc(PLLSS_MISC_DEFAULT, pll); - pll_writel(PLLSS_CFG_DEFAULT, pll_params->ext_misc_reg[0], pll); - pll_writel(PLLSS_CTRL1_DEFAULT, pll_params->ext_misc_reg[1], pll); - pll_writel(PLLSS_CTRL1_DEFAULT, pll_params->ext_misc_reg[2], pll); + _pllss_set_defaults(pll); val = pll_readl_base(pll); val_iddq = readl_relaxed(clk_base + pll_params->iddq_reg); @@ -2546,27 +2581,12 @@ struct clk *tegra_clk_register_plle_tegra210(const char *name, { struct tegra_clk_pll *pll; struct clk *clk; - u32 val, val_aux; pll = _tegra_init_pll(clk_base, NULL, pll_params, lock); if (IS_ERR(pll)) return ERR_CAST(pll); - /* ensure parent is set to pll_re_vco */ - - val = pll_readl_base(pll); - val_aux = pll_readl(pll_params->aux_reg, pll); - - if (val & PLLE_BASE_ENABLE) { - if ((val_aux & PLLE_AUX_PLLRE_SEL) || - (val_aux & PLLE_AUX_PLLP_SEL)) - WARN(1, "pll_e enabled with unsupported parent %s\n", - (val_aux & PLLE_AUX_PLLP_SEL) ? "pllp_out0" : - "pll_re_vco"); - } else { - val_aux &= ~(PLLE_AUX_PLLRE_SEL | PLLE_AUX_PLLP_SEL); - pll_writel(val_aux, pll_params->aux_reg, pll); - } + _clk_plle_tegra_init_parent(pll); clk = _tegra_clk_register_pll(pll, name, parent_name, flags, &tegra_clk_plle_tegra210_ops); @@ -2710,3 +2730,42 @@ struct clk *tegra_clk_register_pllmb(const char *name, const char *parent_name, } #endif + +#if defined(CONFIG_PM_SLEEP) && defined(CONFIG_ARCH_TEGRA_210_SOC) +void tegra_clk_pll_resume(struct clk *c, unsigned long rate) +{ + struct clk_hw *hw = __clk_get_hw(c); + struct tegra_clk_pll *pll = to_clk_pll(hw); + struct clk_hw *parent = clk_hw_get_parent(hw); + + if (clk_pll_is_enabled(hw)) + return; + + if (IS_ERR(parent)) { + WARN_ON(1); + return; + } + + if (pll->params->set_defaults) + pll->params->set_defaults(pll); + + clk_set_rate(c, rate); + clk_pll_enable(hw); +} + +void tegra_clk_sync_state_pll(struct clk *c) +{ + struct clk_hw *hw = __clk_get_hw(c); + + if (!__clk_get_enable_count(c)) + clk_pll_disable(hw); +} + +void tegra_clk_plle_tegra210_resume(struct clk *c) +{ + struct clk_hw *hw = __clk_get_hw(c); + struct tegra_clk_pll *pll = to_clk_pll(hw); + + _clk_plle_tegra_init_parent(pll); +} +#endif diff --git a/drivers/clk/tegra/clk.h b/drivers/clk/tegra/clk.h index 09bccbb9640c..e4d124cc5657 100644 --- a/drivers/clk/tegra/clk.h +++ b/drivers/clk/tegra/clk.h @@ -841,6 +841,15 @@ int tegra_pll_p_div_to_hw(struct tegra_clk_pll *pll, u8 p_div); int div_frac_get(unsigned long rate, unsigned parent_rate, u8 width, u8 frac_width, u8 flags); +#ifdef CONFIG_PM_SLEEP +void tegra_clk_pll_resume(struct clk *c, unsigned long rate); +void tegra_clk_divider_resume(struct clk_hw *hw, unsigned long rate); +void tegra_clk_pll_out_resume(struct clk *clk, unsigned long rate); +void tegra_clk_plle_tegra210_resume(struct clk *c); +void tegra_clk_sync_state_pll(struct clk *c); +void tegra_clk_sync_state_pll_out(struct clk *clk); +#endif + /* Combined read fence with delay */ #define fence_udelay(delay, reg) \
This patch has implementation of saving and restoring PLL's state to support system suspend and resume operations. Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com> --- drivers/clk/tegra/clk-divider.c | 19 ++++++++ drivers/clk/tegra/clk-pll-out.c | 25 +++++++++++ drivers/clk/tegra/clk-pll.c | 99 ++++++++++++++++++++++++++++++++--------- drivers/clk/tegra/clk.h | 9 ++++ 4 files changed, 132 insertions(+), 20 deletions(-)