| Message ID | d6be605205f6af01968a99582b05026aec2eca42.1524737432.git.viresh.kumar@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | None | expand |
Hi Viresh, On jeu., avril 26 2018, Viresh Kumar <viresh.kumar@linaro.org> wrote: > From: Miquel Raynal <miquel.raynal@bootlin.com> > > Add suspend/resume hooks in Armada 37xx DVFS driver to handle S2RAM > operations. As there is currently no 'driver' structure, create one > to store both the regmap and the register values during suspend > operation. I tested this patch on a Armada 3720 based board (EspressoBin), and it worked well. I even made some power consumption measurement and after the resume, the power consumption had the same value that before the suspend, for low CPU frequency and high CPU frequency. Tested-by: Gregory CLEMENT <gregory.clement@bootlin.com> Thanks, Gregory > > Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> > Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> > --- > V3->V4: > - Fix the "unused put_clk label" build error that happened between V2 > and V3. > > drivers/cpufreq/armada-37xx-cpufreq.c | 67 +++++++++++++++++++++++++++++++++-- > 1 file changed, 65 insertions(+), 2 deletions(-) > > diff --git a/drivers/cpufreq/armada-37xx-cpufreq.c b/drivers/cpufreq/armada-37xx-cpufreq.c > index 1d5db6f6ace9..739da90ff3f6 100644 > --- a/drivers/cpufreq/armada-37xx-cpufreq.c > +++ b/drivers/cpufreq/armada-37xx-cpufreq.c > @@ -23,6 +23,8 @@ > #include <linux/regmap.h> > #include <linux/slab.h> > > +#include "cpufreq-dt.h" > + > /* Power management in North Bridge register set */ > #define ARMADA_37XX_NB_L0L1 0x18 > #define ARMADA_37XX_NB_L2L3 0x1C > @@ -56,6 +58,16 @@ > */ > #define LOAD_LEVEL_NR 4 > > +struct armada37xx_cpufreq_state { > + struct regmap *regmap; > + u32 nb_l0l1; > + u32 nb_l2l3; > + u32 nb_dyn_mod; > + u32 nb_cpu_load; > +}; > + > +static struct armada37xx_cpufreq_state *armada37xx_cpufreq_state; > + > struct armada_37xx_dvfs { > u32 cpu_freq_max; > u8 divider[LOAD_LEVEL_NR]; > @@ -136,7 +148,7 @@ static void __init armada37xx_cpufreq_dvfs_setup(struct regmap *base, > clk_set_parent(clk, parent); > } > > -static void __init armada37xx_cpufreq_disable_dvfs(struct regmap *base) > +static void armada37xx_cpufreq_disable_dvfs(struct regmap *base) > { > unsigned int reg = ARMADA_37XX_NB_DYN_MOD, > mask = ARMADA_37XX_NB_DFS_EN; > @@ -162,8 +174,44 @@ static void __init armada37xx_cpufreq_enable_dvfs(struct regmap *base) > regmap_update_bits(base, reg, mask, mask); > } > > +static int armada37xx_cpufreq_suspend(struct cpufreq_policy *policy) > +{ > + struct armada37xx_cpufreq_state *state = armada37xx_cpufreq_state; > + > + regmap_read(state->regmap, ARMADA_37XX_NB_L0L1, &state->nb_l0l1); > + regmap_read(state->regmap, ARMADA_37XX_NB_L2L3, &state->nb_l2l3); > + regmap_read(state->regmap, ARMADA_37XX_NB_CPU_LOAD, > + &state->nb_cpu_load); > + regmap_read(state->regmap, ARMADA_37XX_NB_DYN_MOD, &state->nb_dyn_mod); > + > + return 0; > +} > + > +static int armada37xx_cpufreq_resume(struct cpufreq_policy *policy) > +{ > + struct armada37xx_cpufreq_state *state = armada37xx_cpufreq_state; > + > + /* Ensure DVFS is disabled otherwise the following registers are RO */ > + armada37xx_cpufreq_disable_dvfs(state->regmap); > + > + regmap_write(state->regmap, ARMADA_37XX_NB_L0L1, state->nb_l0l1); > + regmap_write(state->regmap, ARMADA_37XX_NB_L2L3, state->nb_l2l3); > + regmap_write(state->regmap, ARMADA_37XX_NB_CPU_LOAD, > + state->nb_cpu_load); > + > + /* > + * NB_DYN_MOD register is the one that actually enable back DVFS if it > + * was enabled before the suspend operation. This must be done last > + * otherwise other registers are not writable. > + */ > + regmap_write(state->regmap, ARMADA_37XX_NB_DYN_MOD, state->nb_dyn_mod); > + > + return 0; > +} > + > static int __init armada37xx_cpufreq_driver_init(void) > { > + struct cpufreq_dt_platform_data pdata; > struct armada_37xx_dvfs *dvfs; > struct platform_device *pdev; > unsigned long freq; > @@ -213,6 +261,15 @@ static int __init armada37xx_cpufreq_driver_init(void) > return -EINVAL; > } > > + armada37xx_cpufreq_state = kmalloc(sizeof(*armada37xx_cpufreq_state), > + GFP_KERNEL); > + if (!armada37xx_cpufreq_state) { > + clk_put(clk); > + return -ENOMEM; > + } > + > + armada37xx_cpufreq_state->regmap = nb_pm_base; > + > armada37xx_cpufreq_dvfs_setup(nb_pm_base, clk, dvfs->divider); > clk_put(clk); > > @@ -228,7 +285,11 @@ static int __init armada37xx_cpufreq_driver_init(void) > /* Now that everything is setup, enable the DVFS at hardware level */ > armada37xx_cpufreq_enable_dvfs(nb_pm_base); > > - pdev = platform_device_register_simple("cpufreq-dt", -1, NULL, 0); > + pdata.suspend = armada37xx_cpufreq_suspend; > + pdata.resume = armada37xx_cpufreq_resume; > + > + pdev = platform_device_register_data(NULL, "cpufreq-dt", -1, &pdata, > + sizeof(pdata)); > ret = PTR_ERR_OR_ZERO(pdev); > if (ret) > goto disable_dvfs; > @@ -244,6 +305,8 @@ static int __init armada37xx_cpufreq_driver_init(void) > dev_pm_opp_remove(cpu_dev, freq); > } > > + kfree(armada37xx_cpufreq_state); > + > return ret; > } > /* late_initcall, to guarantee the driver is loaded after A37xx clock driver */ > -- > 2.15.0.194.g9af6a3dea062 > -- Gregory Clement, Bootlin (formerly Free Electrons) Embedded Linux and Kernel engineering http://bootlin.com
On 02-05-18, 17:52, Gregory CLEMENT wrote: > Hi Viresh, > > On jeu., avril 26 2018, Viresh Kumar <viresh.kumar@linaro.org> wrote: > > > From: Miquel Raynal <miquel.raynal@bootlin.com> > > > > Add suspend/resume hooks in Armada 37xx DVFS driver to handle S2RAM > > operations. As there is currently no 'driver' structure, create one > > to store both the regmap and the register values during suspend > > operation. > > I tested this patch on a Armada 3720 based board (EspressoBin), and it > worked well. I even made some power consumption measurement and after > the resume, the power consumption had the same value that before the > suspend, for low CPU frequency and high CPU frequency. > > Tested-by: Gregory CLEMENT <gregory.clement@bootlin.com> Thanks Gregory. -- viresh
diff --git a/drivers/cpufreq/armada-37xx-cpufreq.c b/drivers/cpufreq/armada-37xx-cpufreq.c index 1d5db6f6ace9..739da90ff3f6 100644 --- a/drivers/cpufreq/armada-37xx-cpufreq.c +++ b/drivers/cpufreq/armada-37xx-cpufreq.c @@ -23,6 +23,8 @@ #include <linux/regmap.h> #include <linux/slab.h> +#include "cpufreq-dt.h" + /* Power management in North Bridge register set */ #define ARMADA_37XX_NB_L0L1 0x18 #define ARMADA_37XX_NB_L2L3 0x1C @@ -56,6 +58,16 @@ */ #define LOAD_LEVEL_NR 4 +struct armada37xx_cpufreq_state { + struct regmap *regmap; + u32 nb_l0l1; + u32 nb_l2l3; + u32 nb_dyn_mod; + u32 nb_cpu_load; +}; + +static struct armada37xx_cpufreq_state *armada37xx_cpufreq_state; + struct armada_37xx_dvfs { u32 cpu_freq_max; u8 divider[LOAD_LEVEL_NR]; @@ -136,7 +148,7 @@ static void __init armada37xx_cpufreq_dvfs_setup(struct regmap *base, clk_set_parent(clk, parent); } -static void __init armada37xx_cpufreq_disable_dvfs(struct regmap *base) +static void armada37xx_cpufreq_disable_dvfs(struct regmap *base) { unsigned int reg = ARMADA_37XX_NB_DYN_MOD, mask = ARMADA_37XX_NB_DFS_EN; @@ -162,8 +174,44 @@ static void __init armada37xx_cpufreq_enable_dvfs(struct regmap *base) regmap_update_bits(base, reg, mask, mask); } +static int armada37xx_cpufreq_suspend(struct cpufreq_policy *policy) +{ + struct armada37xx_cpufreq_state *state = armada37xx_cpufreq_state; + + regmap_read(state->regmap, ARMADA_37XX_NB_L0L1, &state->nb_l0l1); + regmap_read(state->regmap, ARMADA_37XX_NB_L2L3, &state->nb_l2l3); + regmap_read(state->regmap, ARMADA_37XX_NB_CPU_LOAD, + &state->nb_cpu_load); + regmap_read(state->regmap, ARMADA_37XX_NB_DYN_MOD, &state->nb_dyn_mod); + + return 0; +} + +static int armada37xx_cpufreq_resume(struct cpufreq_policy *policy) +{ + struct armada37xx_cpufreq_state *state = armada37xx_cpufreq_state; + + /* Ensure DVFS is disabled otherwise the following registers are RO */ + armada37xx_cpufreq_disable_dvfs(state->regmap); + + regmap_write(state->regmap, ARMADA_37XX_NB_L0L1, state->nb_l0l1); + regmap_write(state->regmap, ARMADA_37XX_NB_L2L3, state->nb_l2l3); + regmap_write(state->regmap, ARMADA_37XX_NB_CPU_LOAD, + state->nb_cpu_load); + + /* + * NB_DYN_MOD register is the one that actually enable back DVFS if it + * was enabled before the suspend operation. This must be done last + * otherwise other registers are not writable. + */ + regmap_write(state->regmap, ARMADA_37XX_NB_DYN_MOD, state->nb_dyn_mod); + + return 0; +} + static int __init armada37xx_cpufreq_driver_init(void) { + struct cpufreq_dt_platform_data pdata; struct armada_37xx_dvfs *dvfs; struct platform_device *pdev; unsigned long freq; @@ -213,6 +261,15 @@ static int __init armada37xx_cpufreq_driver_init(void) return -EINVAL; } + armada37xx_cpufreq_state = kmalloc(sizeof(*armada37xx_cpufreq_state), + GFP_KERNEL); + if (!armada37xx_cpufreq_state) { + clk_put(clk); + return -ENOMEM; + } + + armada37xx_cpufreq_state->regmap = nb_pm_base; + armada37xx_cpufreq_dvfs_setup(nb_pm_base, clk, dvfs->divider); clk_put(clk); @@ -228,7 +285,11 @@ static int __init armada37xx_cpufreq_driver_init(void) /* Now that everything is setup, enable the DVFS at hardware level */ armada37xx_cpufreq_enable_dvfs(nb_pm_base); - pdev = platform_device_register_simple("cpufreq-dt", -1, NULL, 0); + pdata.suspend = armada37xx_cpufreq_suspend; + pdata.resume = armada37xx_cpufreq_resume; + + pdev = platform_device_register_data(NULL, "cpufreq-dt", -1, &pdata, + sizeof(pdata)); ret = PTR_ERR_OR_ZERO(pdev); if (ret) goto disable_dvfs; @@ -244,6 +305,8 @@ static int __init armada37xx_cpufreq_driver_init(void) dev_pm_opp_remove(cpu_dev, freq); } + kfree(armada37xx_cpufreq_state); + return ret; } /* late_initcall, to guarantee the driver is loaded after A37xx clock driver */