by Roger Lu

[permalink] [raw]

Subject: Re: [PATCH v5 3/3] PM / AVS: SVS: Introduce SVS engine

Dear Kevin Sir,

Sorry for the late reply and thanks for the advice to this patch.

On Thu, 2019-09-26 at 15:39 -0700, Kevin Hilman wrote:
> Hi Roger,
>
> Roger Lu <[email protected]> writes:
>
> > The SVS (Smart Voltage Scaling) engine is a piece of hardware which is
> > used to calculate optimized voltage values of several power domains, e.g.
> > CPU/GPU/CCI, according to chip process corner, temperatures, and other
> > factors. Then DVFS driver could apply those optimized voltage values to
> > reduce power consumption.
> >
> > Signed-off-by: Roger Lu <[email protected]>
>
> I don't have any documentation on this SVS hardware, so I won't be able
> to comment on the specific functionality, so I attempted a first-pass
> high-level review...

Excuse me, we don't have the documentation for SVS hardware. I'll try my
best to introduce SVS online.

>
> In the absence of documentation, it would be helpful to give a high
> level description of how this hardware works. In particular, a
> high-level overview of the control loop, which appears to be primarily
> interrupt driven, would be helpful. e.g. how often are the interrupts
> firing, and why.

1. MT8183 SVS has 4 controllers (banks). One bank for optimizing one
power-domain OPP voltages.
- 4 power-domain (CPU-little / CPU-BIG / CCI / GPU) OPP voltages will be
optimized by SVS banks..
2. Each SVS bank needs to run its init01/init02 separately so that SVS
bank's optimized OPP voltages can be calculated to system.
- init01: SVS bank basic init (must)
- init02: SVS bank provide high temperature OPP voltages (must)
- mon mode: SVS bank dynamically optimizes OPP voltages basing on
temperature change. (optional)
3. SVS interrupt behavior
- In init01/init02, SVS only fire one interrupt to inform SW that init
is finished and optimized OPP voltages are ready.
- In mon mode, SVS fire interrupt when temperature changes. Mon mode
interrupt is also for informing new optimized OPP voltages are ready.

>
> It's hard to understand the "init01" vs the "init02" patch since
> those names aren't very descriptive. :)
>
> Also, there are lots of hard-coded constants (masks, shifts, etc.) used
> throughout the calculations. #defines could help readability for many
> of these, especially the masks.
>
> > ---
> > drivers/power/avs/Kconfig | 10 +
> > drivers/power/avs/Makefile | 1 +
> > drivers/power/avs/mtk_svs.c | 2075 +++++++++++++++++++++++++++++++++
> > include/linux/power/mtk_svs.h | 23 +
> > 4 files changed, 2109 insertions(+)
> > create mode 100644 drivers/power/avs/mtk_svs.c
> > create mode 100644 include/linux/power/mtk_svs.h
> >
> > diff --git a/drivers/power/avs/Kconfig b/drivers/power/avs/Kconfig
> > index b5a217b828dc..7c72504d5593 100644
> > --- a/drivers/power/avs/Kconfig
> > +++ b/drivers/power/avs/Kconfig
> > @@ -19,3 +19,13 @@ config ROCKCHIP_IODOMAIN
> > Say y here to enable support io domains on Rockchip SoCs. It is
> > necessary for the io domain setting of the SoC to match the
> > voltage supplied by the regulators.
> > +
> > +config MTK_SVS
> > + bool "MediaTek Smart Voltage Scaling(SVS)"
> > + depends on POWER_AVS && MTK_EFUSE
> > + help
> > + The SVS engine is a piece of hardware which is used to calculate
> > + optimized voltage values of several power domains, e.g.
> > + CPU clusters/GPU/CCI, according to chip process corner, temperatures,
> > + and other factors. Then DVFS driver could apply those optimized voltage
> > + values to reduce power consumption.
> > diff --git a/drivers/power/avs/Makefile b/drivers/power/avs/Makefile
> > index a1b8cd453f19..57246b977a93 100644
> > --- a/drivers/power/avs/Makefile
> > +++ b/drivers/power/avs/Makefile
> > @@ -1,3 +1,4 @@
> > # SPDX-License-Identifier: GPL-2.0-only
> > obj-$(CONFIG_POWER_AVS_OMAP) += smartreflex.o
> > obj-$(CONFIG_ROCKCHIP_IODOMAIN) += rockchip-io-domain.o
> > +obj-$(CONFIG_MTK_SVS) += mtk_svs.o
> > diff --git a/drivers/power/avs/mtk_svs.c b/drivers/power/avs/mtk_svs.c
> > new file mode 100644
> > index 000000000000..78ec93c3a4a5
> > --- /dev/null
> > +++ b/drivers/power/avs/mtk_svs.c
> > @@ -0,0 +1,2075 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Copyright (C) 2018 MediaTek Inc.
> > + */
> > +
> > +#define pr_fmt(fmt) "[mtk_svs] " fmt
> > +
> > +#include <linux/clk.h>
> > +#include <linux/completion.h>
> > +#include <linux/init.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/kthread.h>
> > +#include <linux/module.h>
> > +#include <linux/mutex.h>
> > +#include <linux/nvmem-consumer.h>
> > +#include <linux/of_address.h>
> > +#include <linux/of_irq.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/pm_domain.h>
> > +#include <linux/pm_opp.h>
> > +#include <linux/pm_qos.h>
> > +#include <linux/pm_runtime.h>
> > +#include <linux/power/mtk_svs.h>
> > +#include <linux/proc_fs.h>
> > +#include <linux/regulator/consumer.h>
> > +#include <linux/seq_file.h>
> > +#include <linux/spinlock.h>
> > +#include <linux/thermal.h>
> > +#include <linux/uaccess.h>
> > +
> > +#define SVS_INIT01_VOLT_IGNORE 1
> > +#define SVS_INIT01_VOLT_INC_ONLY 2
> > +
> > +#define SVS_PHASE_INIT01 0
> > +#define SVS_PHASE_INIT02 1
> > +#define SVS_PHASE_MON 2
> > +#define SVS_PHASE_ERROR 3
> > +
> > +#define SVS_CPU_LITTLE 1
> > +#define SVS_CPU_BIG 2
> > +#define SVS_CCI 3
> > +#define SVS_GPU 4
> > +
> > +#define proc_fops_rw(name) \
> > + static int name ## _proc_open(struct inode *inode, \
> > + struct file *file) \
> > + { \
> > + return single_open(file, name ## _proc_show, \
> > + PDE_DATA(inode)); \
> > + } \
> > + static const struct file_operations name ## _proc_fops = { \
> > + .owner = THIS_MODULE, \
> > + .open = name ## _proc_open, \
> > + .read = seq_read, \
> > + .llseek = seq_lseek, \
> > + .release = single_release, \
> > + .write = name ## _proc_write, \
> > + }
> > +
> > +#define proc_fops_ro(name) \
> > + static int name ## _proc_open(struct inode *inode, \
> > + struct file *file) \
> > + { \
> > + return single_open(file, name ## _proc_show, \
> > + PDE_DATA(inode)); \
> > + } \
> > + static const struct file_operations name ## _proc_fops = { \
> > + .owner = THIS_MODULE, \
> > + .open = name ## _proc_open, \
> > + .read = seq_read, \
> > + .llseek = seq_lseek, \
> > + .release = single_release, \
> > + }
> > +
> > +#define proc_entry(name) {__stringify(name), &name ## _proc_fops}
> > +
> > +static DEFINE_SPINLOCK(mtk_svs_lock);
> > +struct mtk_svs;
> > +
> > +enum reg_index {
> > + TEMPMONCTL0 = 0,
> > + TEMPMONCTL1,
> > + TEMPMONCTL2,
> > + TEMPMONINT,
> > + TEMPMONINTSTS,
> > + TEMPMONIDET0,
> > + TEMPMONIDET1,
> > + TEMPMONIDET2,
> > + TEMPH2NTHRE,
> > + TEMPHTHRE,
> > + TEMPCTHRE,
> > + TEMPOFFSETH,
> > + TEMPOFFSETL,
> > + TEMPMSRCTL0,
> > + TEMPMSRCTL1,
> > + TEMPAHBPOLL,
> > + TEMPAHBTO,
> > + TEMPADCPNP0,
> > + TEMPADCPNP1,
> > + TEMPADCPNP2,
> > + TEMPADCMUX,
> > + TEMPADCEXT,
> > + TEMPADCEXT1,
> > + TEMPADCEN,
> > + TEMPPNPMUXADDR,
> > + TEMPADCMUXADDR,
> > + TEMPADCEXTADDR,
> > + TEMPADCEXT1ADDR,
> > + TEMPADCENADDR,
> > + TEMPADCVALIDADDR,
> > + TEMPADCVOLTADDR,
> > + TEMPRDCTRL,
> > + TEMPADCVALIDMASK,
> > + TEMPADCVOLTAGESHIFT,
> > + TEMPADCWRITECTRL,
> > + TEMPMSR0,
> > + TEMPMSR1,
> > + TEMPMSR2,
> > + TEMPADCHADDR,
> > + TEMPIMMD0,
> > + TEMPIMMD1,
> > + TEMPIMMD2,
> > + TEMPMONIDET3,
> > + TEMPADCPNP3,
> > + TEMPMSR3,
> > + TEMPIMMD3,
> > + TEMPPROTCTL,
> > + TEMPPROTTA,
> > + TEMPPROTTB,
> > + TEMPPROTTC,
> > + TEMPSPARE0,
> > + TEMPSPARE1,
> > + TEMPSPARE2,
> > + TEMPSPARE3,
> > + TEMPMSR0_1,
> > + TEMPMSR1_1,
> > + TEMPMSR2_1,
> > + TEMPMSR3_1,
> > + DESCHAR,
> > + TEMPCHAR,
> > + DETCHAR,
> > + AGECHAR,
> > + DCCONFIG,
> > + AGECONFIG,
> > + FREQPCT30,
> > + FREQPCT74,
> > + LIMITVALS,
> > + VBOOT,
> > + DETWINDOW,
> > + CONFIG,
> > + TSCALCS,
> > + RUNCONFIG,
> > + SVSEN,
> > + INIT2VALS,
> > + DCVALUES,
> > + AGEVALUES,
> > + VOP30,
> > + VOP74,
> > + TEMP,
> > + INTSTS,
> > + INTSTSRAW,
> > + INTEN,
> > + CHKINT,
> > + CHKSHIFT,
> > + STATUS,
> > + VDESIGN30,
> > + VDESIGN74,
> > + DVT30,
> > + DVT74,
> > + AGECOUNT,
> > + SMSTATE0,
> > + SMSTATE1,
> > + CTL0,
> > + DESDETSEC,
> > + TEMPAGESEC,
> > + CTRLSPARE0,
> > + CTRLSPARE1,
> > + CTRLSPARE2,
> > + CTRLSPARE3,
> > + CORESEL,
> > + THERMINTST,
> > + INTST,
> > + THSTAGE0ST,
> > + THSTAGE1ST,
> > + THSTAGE2ST,
> > + THAHBST0,
> > + THAHBST1,
> > + SPARE0,
> > + SPARE1,
> > + SPARE2,
> > + SPARE3,
> > + THSLPEVEB,
> > + reg_num,
> > +};
> > +
> > +static const u32 svs_regs_v2[] = {
> > + [TEMPMONCTL0] = 0x000,
> > + [TEMPMONCTL1] = 0x004,
> > + [TEMPMONCTL2] = 0x008,
> > + [TEMPMONINT] = 0x00c,
> > + [TEMPMONINTSTS] = 0x010,
> > + [TEMPMONIDET0] = 0x014,
> > + [TEMPMONIDET1] = 0x018,
> > + [TEMPMONIDET2] = 0x01c,
> > + [TEMPH2NTHRE] = 0x024,
> > + [TEMPHTHRE] = 0x028,
> > + [TEMPCTHRE] = 0x02c,
> > + [TEMPOFFSETH] = 0x030,
> > + [TEMPOFFSETL] = 0x034,
> > + [TEMPMSRCTL0] = 0x038,
> > + [TEMPMSRCTL1] = 0x03c,
> > + [TEMPAHBPOLL] = 0x040,
> > + [TEMPAHBTO] = 0x044,
> > + [TEMPADCPNP0] = 0x048,
> > + [TEMPADCPNP1] = 0x04c,
> > + [TEMPADCPNP2] = 0x050,
> > + [TEMPADCMUX] = 0x054,
> > + [TEMPADCEXT] = 0x058,
> > + [TEMPADCEXT1] = 0x05c,
> > + [TEMPADCEN] = 0x060,
> > + [TEMPPNPMUXADDR] = 0x064,
> > + [TEMPADCMUXADDR] = 0x068,
> > + [TEMPADCEXTADDR] = 0x06c,
> > + [TEMPADCEXT1ADDR] = 0x070,
> > + [TEMPADCENADDR] = 0x074,
> > + [TEMPADCVALIDADDR] = 0x078,
> > + [TEMPADCVOLTADDR] = 0x07c,
> > + [TEMPRDCTRL] = 0x080,
> > + [TEMPADCVALIDMASK] = 0x084,
> > + [TEMPADCVOLTAGESHIFT] = 0x088,
> > + [TEMPADCWRITECTRL] = 0x08c,
> > + [TEMPMSR0] = 0x090,
> > + [TEMPMSR1] = 0x094,
> > + [TEMPMSR2] = 0x098,
> > + [TEMPADCHADDR] = 0x09c,
> > + [TEMPIMMD0] = 0x0a0,
> > + [TEMPIMMD1] = 0x0a4,
> > + [TEMPIMMD2] = 0x0a8,
> > + [TEMPMONIDET3] = 0x0b0,
> > + [TEMPADCPNP3] = 0x0b4,
> > + [TEMPMSR3] = 0x0b8,
> > + [TEMPIMMD3] = 0x0bc,
> > + [TEMPPROTCTL] = 0x0c0,
> > + [TEMPPROTTA] = 0x0c4,
> > + [TEMPPROTTB] = 0x0c8,
> > + [TEMPPROTTC] = 0x0cc,
> > + [TEMPSPARE0] = 0x0f0,
> > + [TEMPSPARE1] = 0x0f4,
> > + [TEMPSPARE2] = 0x0f8,
> > + [TEMPSPARE3] = 0x0fc,
> > + [TEMPMSR0_1] = 0x190,
> > + [TEMPMSR1_1] = 0x194,
> > + [TEMPMSR2_1] = 0x198,
> > + [TEMPMSR3_1] = 0x1b8,
> > + [DESCHAR] = 0xc00,
> > + [TEMPCHAR] = 0xc04,
> > + [DETCHAR] = 0xc08,
> > + [AGECHAR] = 0xc0c,
> > + [DCCONFIG] = 0xc10,
> > + [AGECONFIG] = 0xc14,
> > + [FREQPCT30] = 0xc18,
> > + [FREQPCT74] = 0xc1c,
> > + [LIMITVALS] = 0xc20,
> > + [VBOOT] = 0xc24,
> > + [DETWINDOW] = 0xc28,
> > + [CONFIG] = 0xc2c,
> > + [TSCALCS] = 0xc30,
> > + [RUNCONFIG] = 0xc34,
> > + [SVSEN] = 0xc38,
> > + [INIT2VALS] = 0xc3c,
> > + [DCVALUES] = 0xc40,
> > + [AGEVALUES] = 0xc44,
> > + [VOP30] = 0xc48,
> > + [VOP74] = 0xc4c,
> > + [TEMP] = 0xc50,
> > + [INTSTS] = 0xc54,
> > + [INTSTSRAW] = 0xc58,
> > + [INTEN] = 0xc5c,
> > + [CHKINT] = 0xc60,
> > + [CHKSHIFT] = 0xc64,
> > + [STATUS] = 0xc68,
> > + [VDESIGN30] = 0xc6c,
> > + [VDESIGN74] = 0xc70,
> > + [DVT30] = 0xc74,
> > + [DVT74] = 0xc78,
> > + [AGECOUNT] = 0xc7c,
> > + [SMSTATE0] = 0xc80,
> > + [SMSTATE1] = 0xc84,
> > + [CTL0] = 0xc88,
> > + [DESDETSEC] = 0xce0,
> > + [TEMPAGESEC] = 0xce4,
> > + [CTRLSPARE0] = 0xcf0,
> > + [CTRLSPARE1] = 0xcf4,
> > + [CTRLSPARE2] = 0xcf8,
> > + [CTRLSPARE3] = 0xcfc,
> > + [CORESEL] = 0xf00,
> > + [THERMINTST] = 0xf04,
> > + [INTST] = 0xf08,
> > + [THSTAGE0ST] = 0xf0c,
> > + [THSTAGE1ST] = 0xf10,
> > + [THSTAGE2ST] = 0xf14,
> > + [THAHBST0] = 0xf18,
> > + [THAHBST1] = 0xf1c,
> > + [SPARE0] = 0xf20,
> > + [SPARE1] = 0xf24,
> > + [SPARE2] = 0xf28,
> > + [SPARE3] = 0xf2c,
> > + [THSLPEVEB] = 0xf30,
> > +};
> > +
> > +struct thermal_parameter {
> > + int adc_ge_t;
> > + int adc_oe_t;
> > + int ge;
> > + int oe;
> > + int gain;
> > + int o_vtsabb;
> > + int o_vtsmcu1;
> > + int o_vtsmcu2;
> > + int o_vtsmcu3;
> > + int o_vtsmcu4;
> > + int o_vtsmcu5;
> > + int degc_cali;
> > + int adc_cali_en_t;
> > + int o_slope;
> > + int o_slope_sign;
> > + int ts_id;
> > +};
> > +
> > +struct svs_bank_ops {
> > + void (*set_freqs_pct)(struct mtk_svs *svs);
> > + void (*get_vops)(struct mtk_svs *svs);
> > +};
> > +
> > +struct svs_bank {
> > + struct svs_bank_ops *ops;
> > + struct completion init_completion;
> > + struct device *dev;
> > + struct regulator *buck;
> > + struct mutex lock; /* lock to protect update voltage process */
> > + bool suspended;
> > + bool mtcmos_request;
> > + bool init01_support;
> > + bool init02_support;
> > + bool mon_mode_support;
> > + s32 volt_offset;
> > + u32 *opp_freqs;
> > + u32 *freqs_pct;
> > + u32 *opp_volts;
> > + u32 *init02_volts;
> > + u32 *volts;
> > + u32 reg_data[3][reg_num];
> > + u32 freq_base;
> > + u32 vboot;
> > + u32 volt_step;
> > + u32 volt_base;
> > + u32 init01_volt_flag;
> > + u32 phase;
> > + u32 vmax;
> > + u32 vmin;
> > + u32 bts;
> > + u32 mts;
> > + u32 bdes;
> > + u32 mdes;
> > + u32 mtdes;
> > + u32 dcbdet;
> > + u32 dcmdet;
> > + u32 dthi;
> > + u32 dtlo;
> > + u32 det_window;
> > + u32 det_max;
> > + u32 age_config;
> > + u32 age_voffset_in;
> > + u32 agem;
> > + u32 dc_config;
> > + u32 dc_voffset_in;
> > + u32 dvt_fixed;
> > + u32 vco;
> > + u32 chkshift;
> > + u32 svs_temp;
> > + u32 upper_temp_bound;
> > + u32 lower_temp_bound;
> > + u32 low_temp_threashold;
> > + u32 low_temp_offset;
> > + u32 coresel;
> > + u32 opp_count;
> > + u32 intst;
> > + u32 systemclk_en;
> > + u32 sw_id;
> > + u32 hw_id;
> > + u32 ctl0;
> > + u8 *of_compatible;
> > + u8 *name;
> > + u8 *zone_name;
> > + u8 *buck_name;
> > +};
> > +
> > +struct svs_platform {
> > + struct svs_bank *banks;
> > + int (*efuse_parsing)(struct mtk_svs *svs);
> > + bool fake_efuse;
> > + const u32 *regs;
> > + u32 bank_num;
> > + u32 efuse_num;
> > + u32 efuse_check;
> > + u32 thermal_efuse_num;
> > + u8 *name;
> > +};
> > +
> > +struct mtk_svs {
> > + const struct svs_platform *platform;
> > + struct svs_bank *bank;
> > + struct device *dev;
> > + void __iomem *base;
> > + struct clk *main_clk;
> > + u32 *efuse;
> > + u32 *thermal_efuse;
> > +};
> > +
> > +unsigned long claim_mtk_svs_lock(void)
> > +{
> > + unsigned long flags;
> > +
> > + spin_lock_irqsave(&mtk_svs_lock, flags);
> > +
> > + return flags;
> > +}
> > +EXPORT_SYMBOL_GPL(claim_mtk_svs_lock);
> > +
> > +void release_mtk_svs_lock(unsigned long flags)
> > +{
> > + spin_unlock_irqrestore(&mtk_svs_lock, flags);
> > +}
> > +EXPORT_SYMBOL_GPL(release_mtk_svs_lock);
>
> I don't see the need for these wrapper functions. You seem to be
> declaring this lock in the header which implies there are external
> users, but there is none in this series, so this lock should stay local
> IMO.

This export API is for mtk thermal driver.
https://patchwork.kernel.org/patch/10938841/

>
> > +static u32 percent(u32 numerator, u32 denominator)
> > +{
> > + u32 percent;
> > +
> > + /* If not divide 1000, "numerator * 100" would be data overflow. */
> > + numerator /= 1000;
> > + denominator /= 1000;
> > + percent = ((numerator * 100) + denominator - 1) / denominator;
> > +
> > + return percent;
> > +}
>
> Maybe some math helpers from math64.h would help you not have to
> open-code this?

Oh, thanks for the reminding. I haven't found the suitable "percent()
API" from math64.h and will keep looking suitable API to replace these
codes.

>
> > +static u32 svs_readl(struct mtk_svs *svs, enum reg_index i)
> > +{
> > + return readl(svs->base + svs->platform->regs[i]);
> > +}
> > +
> > +static void svs_writel(struct mtk_svs *svs, u32 val, enum reg_index i)
> > +{
> > + writel(val, svs->base + svs->platform->regs[i]);
> > +}
> > +
> > +static void svs_switch_bank(struct mtk_svs *svs)
> > +{
> > + struct svs_bank *svsb = svs->bank;
> > +
> > + svs_writel(svs, svsb->coresel, CORESEL);
> > +}
> > +
> > +static u32 svs_volt_to_opp_volt(u32 svsb_volt,
> > + u32 svsb_volt_step, u32 svsb_volt_base)
> > +{
> > + u32 u_volt;
> > +
> > + u_volt = (svsb_volt * svsb_volt_step) + svsb_volt_base;
> > +
> > + return u_volt;
> > +}
> > +
> > +static int svs_get_zone_temperature(struct svs_bank *svsb, int *zone_temp)
> > +{
> > + struct thermal_zone_device *tzd;
> > + int ret;
> > +
> > + tzd = thermal_zone_get_zone_by_name(svsb->zone_name);
> > + ret = thermal_zone_get_temp(tzd, zone_temp);
> > +
> > + return ret;
> > +}
> > +
> > +static int svs_set_volts(struct svs_bank *svsb, bool force_update)
> > +{
> > + u32 i, svsb_volt, opp_volt, low_temp_offset = 0;
> > + int zone_temp, ret;
> > +
> > + mutex_lock(&svsb->lock);
> > +
> > + /* If bank is suspended, it means init02 voltage is applied.
> > + * Don't need to update opp voltage anymore.
> > + */
>
> minor nit: fix multi-line comment style

Sure. I'll fix it in the next patch.Thanks.

>
> > + if (svsb->suspended && !force_update) {
> > + pr_notice("%s: bank is suspended\n", svsb->name);
> > + mutex_unlock(&svsb->lock);
> > + return -EPERM;
> > + }
> > +
> > + /* get thermal effect */
> > + if (svsb->phase == SVS_PHASE_MON) {
> > + if (svsb->svs_temp > svsb->upper_temp_bound &&
> > + svsb->svs_temp < svsb->lower_temp_bound) {
> > + pr_err("%s: svs_temp is abnormal (0x%x)?\n",
> > + svsb->name, svsb->svs_temp);
> > + mutex_unlock(&svsb->lock);
> > + return -EINVAL;
> > + }
> > +
> > + ret = svs_get_zone_temperature(svsb, &zone_temp);
> > + if (ret) {
> > + pr_err("%s: cannot get zone \"%s\" temperature\n",
> > + svsb->name, svsb->zone_name);
> > + pr_err("%s: add low_temp_offset = %u\n",
> > + svsb->name, svsb->low_temp_offset);
> > + zone_temp = svsb->low_temp_threashold;
> > + }
> > +
> > + if (zone_temp <= svsb->low_temp_threashold)
> > + low_temp_offset = svsb->low_temp_offset;
> > + }
> > +
> > + /* vmin <= svsb_volt (opp_volt) <= signed-off voltage */
> > + for (i = 0; i < svsb->opp_count; i++) {
> > + if (svsb->phase == SVS_PHASE_MON) {
> > + svsb_volt = max((svsb->volts[i] + svsb->volt_offset +
> > + low_temp_offset), svsb->vmin);
> > + opp_volt = svs_volt_to_opp_volt(svsb_volt,
> > + svsb->volt_step,
> > + svsb->volt_base);
> > + } else if (svsb->phase == SVS_PHASE_INIT02) {
> > + svsb_volt = max((svsb->init02_volts[i] +
> > + svsb->volt_offset), svsb->vmin);
> > + opp_volt = svs_volt_to_opp_volt(svsb_volt,
> > + svsb->volt_step,
> > + svsb->volt_base);
> > + } else if (svsb->phase == SVS_PHASE_ERROR) {
> > + opp_volt = svsb->opp_volts[i];
> > + } else {
> > + pr_err("%s: unknown phase: %u?\n",
> > + svsb->name, svsb->phase);
> > + mutex_unlock(&svsb->lock);
> > + return -EINVAL;
> > + }
> > +
> > + opp_volt = min(opp_volt, svsb->opp_volts[i]);
> > + ret = dev_pm_opp_adjust_voltage(svsb->dev, svsb->opp_freqs[i],
> > + opp_volt);
> > + if (ret) {
> > + pr_err("%s: set voltage failed: %d\n", svsb->name, ret);
> > + mutex_unlock(&svsb->lock);
> > + return ret;
> > + }
> > + }
> > +
> > + mutex_unlock(&svsb->lock);
> > +
> > + return 0;
> > +}
> > +
> > +static u32 interpolate(u32 f0, u32 f1, u32 v0, u32 v1, u32 fx)
> > +{
> > + u32 vy;
> > +
> > + if (v0 == v1 || f0 == f1)
> > + return v0;
> > +
> > + /* *100 to have decimal fraction factor, +99 for rounding up. */
> > + vy = (v0 * 100) - ((((v0 - v1) * 100) / (f0 - f1)) * (f0 - fx));
> > + vy = (vy + 99) / 100;
> > +
> > + return vy;
> > +}
> > +
> > +static void svs_get_vops_v2(struct mtk_svs *svs)
> > +{
> > + struct svs_bank *svsb = svs->bank;
> > + u32 temp, i;
> > +
> > + temp = svs_readl(svs, VOP30);
> > + svsb->volts[6] = (temp >> 24) & 0xff;
> > + svsb->volts[4] = (temp >> 16) & 0xff;
> > + svsb->volts[2] = (temp >> 8) & 0xff;
> > + svsb->volts[0] = (temp & 0xff);
> > +
> > + temp = svs_readl(svs, VOP74);
> > + svsb->volts[14] = (temp >> 24) & 0xff;
> > + svsb->volts[12] = (temp >> 16) & 0xff;
> > + svsb->volts[10] = (temp >> 8) & 0xff;
> > + svsb->volts[8] = (temp & 0xff);
> > +
> > + for (i = 0; i <= 7; i++) {
> > + if (i < 7) {
> > + svsb->volts[(i * 2) + 1] =
> > + interpolate(svsb->freqs_pct[i * 2],
> > + svsb->freqs_pct[(i + 1) * 2],
> > + svsb->volts[i * 2],
> > + svsb->volts[(i + 1) * 2],
> > + svsb->freqs_pct[(i * 2) + 1]);
> > + } else if (i == 7) {
> > + svsb->volts[(i * 2) + 1] =
> > + interpolate(svsb->freqs_pct[(i - 1) * 2],
> > + svsb->freqs_pct[i * 2],
> > + svsb->volts[(i - 1) * 2],
> > + svsb->volts[i * 2],
> > + svsb->freqs_pct[(i * 2) + 1]);
> > + }
> > + }
> > +}
> > +
> > +static void svs_set_freqs_pct_v2(struct mtk_svs *svs)
> > +{
> > + struct svs_bank *svsb = svs->bank;
> > +
> > + svs_writel(svs,
> > + ((svsb->freqs_pct[6] << 24) & 0xff000000) |
> > + ((svsb->freqs_pct[4] << 16) & 0xff0000) |
> > + ((svsb->freqs_pct[2] << 8) & 0xff00) |
> > + (svsb->freqs_pct[0] & 0xff),
> > + FREQPCT30);
> > + svs_writel(svs,
> > + ((svsb->freqs_pct[14] << 24) & 0xff000000) |
> > + ((svsb->freqs_pct[12] << 16) & 0xff0000) |
> > + ((svsb->freqs_pct[10] << 8) & 0xff00) |
> > + ((svsb->freqs_pct[8]) & 0xff),
> > + FREQPCT74);
> > +}
> > +
> > +static void svs_set_phase(struct mtk_svs *svs, u32 target_phase)
> > +{
> > + struct svs_bank *svsb = svs->bank;
> > + u32 des_char, temp_char, det_char, limit_vals;
> > + u32 init2vals, ts_calcs, val, filter, i;
> > +
> > + svs_switch_bank(svs);
> > +
> > + des_char = ((svsb->bdes << 8) & 0xff00) | (svsb->mdes & 0xff);
> > + svs_writel(svs, des_char, DESCHAR);
> > +
> > + temp_char = ((svsb->vco << 16) & 0xff0000) |
> > + ((svsb->mtdes << 8) & 0xff00) |
> > + (svsb->dvt_fixed & 0xff);
> > + svs_writel(svs, temp_char, TEMPCHAR);
> > +
> > + det_char = ((svsb->dcbdet << 8) & 0xff00) | (svsb->dcmdet & 0xff);
> > + svs_writel(svs, det_char, DETCHAR);
> > +
> > + svs_writel(svs, svsb->dc_config, DCCONFIG);
> > + svs_writel(svs, svsb->age_config, AGECONFIG);
> > +
> > + if (svsb->agem == 0x0) {
> > + svs_writel(svs, 0x80000000, RUNCONFIG);
> > + } else {
> > + val = 0x0;
> > +
> > + for (i = 0; i < 24; i += 2) {
> > + filter = 0x3 << i;
> > +
> > + if ((svsb->age_config & filter) == 0x0)
> > + val |= (0x1 << i);
> > + else
> > + val |= (svsb->age_config & filter);
> > + }
> > + svs_writel(svs, val, RUNCONFIG);
> > + }
> > +
> > + svsb->ops->set_freqs_pct(svs);
> > +
> > + limit_vals = ((svsb->vmax << 24) & 0xff000000) |
> > + ((svsb->vmin << 16) & 0xff0000) |
> > + ((svsb->dthi << 8) & 0xff00) |
> > + (svsb->dtlo & 0xff);
> > + svs_writel(svs, limit_vals, LIMITVALS);
> > + svs_writel(svs, (svsb->vboot & 0xff), VBOOT);
> > + svs_writel(svs, (svsb->det_window & 0xffff), DETWINDOW);
> > + svs_writel(svs, (svsb->det_max & 0xffff), CONFIG);
> > +
> > + if (svsb->chkshift != 0)
> > + svs_writel(svs, (svsb->chkshift & 0xff), CHKSHIFT);
> > +
> > + if (svsb->ctl0 != 0)
> > + svs_writel(svs, svsb->ctl0, CTL0);
> > +
> > + svs_writel(svs, 0x00ffffff, INTSTS);
> > +
> > + switch (target_phase) {
> > + case SVS_PHASE_INIT01:
> > + svs_writel(svs, 0x00005f01, INTEN);
> > + svs_writel(svs, 0x00000001, SVSEN);
> > + break;
> > + case SVS_PHASE_INIT02:
> > + svs_writel(svs, 0x00005f01, INTEN);
> > + init2vals = ((svsb->age_voffset_in << 16) & 0xffff0000) |
> > + (svsb->dc_voffset_in & 0xffff);
> > + svs_writel(svs, init2vals, INIT2VALS);
> > + svs_writel(svs, 0x00000005, SVSEN);
> > + break;
> > + case SVS_PHASE_MON:
> > + ts_calcs = ((svsb->bts << 12) & 0xfff000) | (svsb->mts & 0xfff);
> > + svs_writel(svs, ts_calcs, TSCALCS);
> > + svs_writel(svs, 0x00FF0000, INTEN);
> > + svs_writel(svs, 0x00000002, SVSEN);
> > + break;
> > + default:
> > + WARN_ON(1);
> > + break;
> > + }
> > +}
>
> lots of magic constants for these register writes. #defines w/bit
> descriptions would be very helpful for the reader.

Sure, I'll add #define w/bit for these magic constants in the next
patch. Thanks.

>
> > +static inline void svs_init01_isr_handler(struct mtk_svs *svs)
> > +{
> > + struct svs_bank *svsb = svs->bank;
> > + enum reg_index rg_i;
> > +
> > + pr_notice("%s: %s: VDN74:0x%08x, VDN30:0x%08x, DCVALUES:0x%08x\n",
> > + svsb->name, __func__, svs_readl(svs, VDESIGN74),
> > + svs_readl(svs, VDESIGN30), svs_readl(svs, DCVALUES));
> > +
> > + for (rg_i = TEMPMONCTL0; rg_i < reg_num; rg_i++)
> > + svsb->reg_data[SVS_PHASE_INIT01][rg_i] = svs_readl(svs, rg_i);
> > +
> > + svsb->dc_voffset_in = ~(svs_readl(svs, DCVALUES) & 0xffff) + 1;
> > + if (svsb->init01_volt_flag == SVS_INIT01_VOLT_IGNORE)
> > + svsb->dc_voffset_in = 0;
> > + else if ((svsb->dc_voffset_in & 0x8000) &&
> > + (svsb->init01_volt_flag == SVS_INIT01_VOLT_INC_ONLY))
> > + svsb->dc_voffset_in = 0;
> > +
> > + svsb->age_voffset_in = svs_readl(svs, AGEVALUES) & 0xffff;
> > +
> > + svs_writel(svs, 0x0, SVSEN);
> > + svs_writel(svs, 0x1, INTSTS);
> > +
> > + /* svs init01 clock gating */
> > + svsb->coresel &= ~svsb->systemclk_en;
> > +
> > + svsb->phase = SVS_PHASE_INIT01;
> > + complete(&svsb->init_completion);
> > +}
> > +
> > +static inline void svs_init02_isr_handler(struct mtk_svs *svs)
> > +{
> > + struct svs_bank *svsb = svs->bank;
> > + enum reg_index rg_i;
> > +
> > + pr_notice("%s: %s: VOP74:0x%08x, VOP30:0x%08x, DCVALUES:0x%08x\n",
> > + svsb->name, __func__, svs_readl(svs, VOP74),
> > + svs_readl(svs, VOP30), svs_readl(svs, DCVALUES));
> > +
> > + for (rg_i = TEMPMONCTL0; rg_i < reg_num; rg_i++)
> > + svsb->reg_data[SVS_PHASE_INIT02][rg_i] = svs_readl(svs, rg_i);
> > +
> > + svsb->ops->get_vops(svs);
> > + memcpy(svsb->init02_volts, svsb->volts, 4 * svsb->opp_count);
> > + svsb->phase = SVS_PHASE_INIT02;
> > +
> > + svs_writel(svs, 0x0, SVSEN);
> > + svs_writel(svs, 0x1, INTSTS);
> > +
> > + complete(&svsb->init_completion);
> > +}
> > +
> > +static inline void svs_mon_mode_isr_handler(struct mtk_svs *svs)
> > +{
> > + struct svs_bank *svsb = svs->bank;
> > + enum reg_index rg_i;
> > +
> > + for (rg_i = TEMPMONCTL0; rg_i < reg_num; rg_i++)
> > + svsb->reg_data[SVS_PHASE_MON][rg_i] = svs_readl(svs, rg_i);
> > +
> > + svsb->svs_temp = svs_readl(svs, TEMP) & 0xff;
> > +
> > + svsb->ops->get_vops(svs);
> > + svsb->phase = SVS_PHASE_MON;
> > +
> > + svs_writel(svs, 0x00ff0000, INTSTS);
> > +}
> > +
> > +static inline void svs_error_isr_handler(struct mtk_svs *svs)
> > +{
> > + const struct svs_platform *svsp = svs->platform;
> > + struct svs_bank *svsb = svs->bank;
> > + enum reg_index rg_i;
> > +
> > + pr_err("%s(): %s(%s)", __func__, svsp->name, svsb->name);
> > + pr_err("CORESEL(0x%x) = 0x%08x\n",
> > + svsp->regs[CORESEL], svs_readl(svs, CORESEL)),
> > + pr_err("SVSEN(0x%x) = 0x%08x, INTSTS(0x%x) = 0x%08x\n",
> > + svsp->regs[SVSEN], svs_readl(svs, SVSEN),
> > + svsp->regs[INTSTS], svs_readl(svs, INTSTS));
> > + pr_err("SMSTATE0(0x%x) = 0x%08x, SMSTATE1(0x%x) = 0x%08x\n",
> > + svsp->regs[SMSTATE0], svs_readl(svs, SMSTATE0),
> > + svsp->regs[SMSTATE1], svs_readl(svs, SMSTATE1));
> > +
> > + for (rg_i = TEMPMONCTL0; rg_i < reg_num; rg_i++)
> > + svsb->reg_data[SVS_PHASE_MON][rg_i] = svs_readl(svs, rg_i);
> > +
> > + svsb->init01_support = false;
> > + svsb->init02_support = false;
> > + svsb->mon_mode_support = false;
> > +
> > + if (svsb->phase == SVS_PHASE_MON)
> > + svsb->phase = SVS_PHASE_INIT02;
> > +
> > + svs_writel(svs, 0x0, SVSEN);
> > + svs_writel(svs, 0x00ffffff, INTSTS);
> > +}
> > +
> > +static inline void svs_isr_handler(struct mtk_svs *svs)
> > +{
> > + u32 intsts, svsen;
> > +
> > + svs_switch_bank(svs);
> > +
> > + intsts = svs_readl(svs, INTSTS);
> > + svsen = svs_readl(svs, SVSEN);
> > +
> > + if (intsts == 0x1 && ((svsen & 0x7) == 0x1))
> > + svs_init01_isr_handler(svs);
> > + else if ((intsts == 0x1) && ((svsen & 0x7) == 0x5))
> > + svs_init02_isr_handler(svs);
> > + else if ((intsts & 0x00ff0000) != 0x0)
> > + svs_mon_mode_isr_handler(svs);
> > + else
> > + svs_error_isr_handler(svs);
> > +}
> > +
> > +static irqreturn_t svs_isr(int irq, void *data)
> > +{
> > + struct mtk_svs *svs = (struct mtk_svs *)data;
> > + const struct svs_platform *svsp = svs->platform;
> > + struct svs_bank *svsb = NULL;
> > + unsigned long flags;
> > + u32 idx;
> > +
> > + flags = claim_mtk_svs_lock();
> > + for (idx = 0; idx < svsp->bank_num; idx++) {
> > + svsb = &svsp->banks[idx];
> > + svs->bank = svsb;
> > +
> > + if (svsb->suspended)
> > + continue;
> > + else if (svsb->intst & svs_readl(svs, INTST))
> > + continue;
> > +
> > + svs_isr_handler(svs);
> > + break;
> > + }
> > + release_mtk_svs_lock(flags);
> > +
> > + if (svsb->phase != SVS_PHASE_INIT01)
> > + svs_set_volts(svsb, false);
> > +
> > + return IRQ_HANDLED;
> > +}
> > +
> > +static void svs_mon_mode(struct mtk_svs *svs)
> > +{
> > + const struct svs_platform *svsp = svs->platform;
> > + struct svs_bank *svsb;
> > + unsigned long flags;
> > + u32 idx;
> > +
> > + flags = claim_mtk_svs_lock();
> > + for (idx = 0; idx < svsp->bank_num; idx++) {
> > + svsb = &svsp->banks[idx];
> > + svs->bank = svsb;
> > +
> > + if (!svsb->mon_mode_support)
> > + continue;
> > +
> > + svs_set_phase(svs, SVS_PHASE_MON);
> > + }
> > + release_mtk_svs_lock(flags);
> > +}
> > +
> > +static int svs_init02(struct mtk_svs *svs)
> > +{
> > + const struct svs_platform *svsp = svs->platform;
> > + struct svs_bank *svsb;
> > + unsigned long flags, time_left;
> > + u32 idx;
> > +
> > + for (idx = 0; idx < svsp->bank_num; idx++) {
> > + svsb = &svsp->banks[idx];
> > + svs->bank = svsb;
> > +
> > + if (!svsb->init02_support)
> > + continue;
> > +
> > + reinit_completion(&svsb->init_completion);
> > + flags = claim_mtk_svs_lock();
> > + svs_set_phase(svs, SVS_PHASE_INIT02);
> > + release_mtk_svs_lock(flags);
> > + time_left =
> > + wait_for_completion_timeout(&svsb->init_completion,
> > + msecs_to_jiffies(2000));
> > + if (time_left == 0) {
> > + pr_err("%s: init02 completion timeout\n", svsb->name);
> > + return -EBUSY;
> > + }
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +static int svs_init01(struct mtk_svs *svs)
> > +{
> > + const struct svs_platform *svsp = svs->platform;
> > + struct svs_bank *svsb;
> > + struct pm_qos_request qos_request = { {0} };
> > + unsigned long flags, time_left;
> > + bool search_done;
> > + int ret = -EINVAL;
> > + u32 opp_freqs, opp_vboot, buck_volt, idx, i;
> > +
> > + /* Let CPUs leave idle-off state for initializing svs_init01. */
> > + pm_qos_add_request(&qos_request, PM_QOS_CPU_DMA_LATENCY, 0);
> > +
> > + /* Sometimes two svs_bank use the same buck.
> > + * Therefore, we set each svs_bank to vboot voltage first.
> > + */
> > + for (idx = 0; idx < svsp->bank_num; idx++) {
> > + svsb = &svsp->banks[idx];
> > + search_done = false;
> > +
> > + if (!svsb->init01_support)
> > + continue;
> > +
> > + ret = regulator_set_mode(svsb->buck, REGULATOR_MODE_FAST);
> > + if (ret)
> > + pr_notice("%s: fail to set fast mode: %d\n",
> > + svsb->name, ret);
> > +
> > + if (svsb->mtcmos_request) {
> > + ret = regulator_enable(svsb->buck);
> > + if (ret) {
> > + pr_err("%s: fail to enable %s power: %d\n",
> > + svsb->name, svsb->buck_name, ret);
> > + goto init01_finish;
> > + }
> > +
> > + ret = dev_pm_domain_attach(svsb->dev, false);
> > + if (ret) {
> > + pr_err("%s: attach pm domain fail: %d\n",
> > + svsb->name, ret);
> > + goto init01_finish;
> > + }
> > +
> > + pm_runtime_enable(svsb->dev);
> > + ret = pm_runtime_get_sync(svsb->dev);
> > + if (ret < 0) {
> > + pr_err("%s: turn mtcmos on fail: %d\n",
> > + svsb->name, ret);
> > + goto init01_finish;
> > + }
> > + }
> > +
> > + /* Find the fastest freq that can be run at vboot and
> > + * fix to that freq until svs_init01 is done.
> > + */
> > + opp_vboot = svs_volt_to_opp_volt(svsb->vboot,
> > + svsb->volt_step,
> > + svsb->volt_base);
> > +
> > + for (i = 0; i < svsb->opp_count; i++) {
> > + opp_freqs = svsb->opp_freqs[i];
> > + if (!search_done && svsb->opp_volts[i] <= opp_vboot) {
> > + ret = dev_pm_opp_adjust_voltage(svsb->dev,
> > + opp_freqs,
> > + opp_vboot);
> > + if (ret) {
> > + pr_err("%s: set voltage failed: %d\n",
> > + svsb->name, ret);
> > + goto init01_finish;
> > + }
> > +
> > + search_done = true;
> > + } else {
> > + dev_pm_opp_disable(svsb->dev,
> > + svsb->opp_freqs[i]);
> > + }
> > + }
> > + }
> > +
> > + for (idx = 0; idx < svsp->bank_num; idx++) {
> > + svsb = &svsp->banks[idx];
> > + svs->bank = svsb;
> > +
> > + if (!svsb->init01_support)
> > + continue;
> > +
> > + opp_vboot = svs_volt_to_opp_volt(svsb->vboot,
> > + svsb->volt_step,
> > + svsb->volt_base);
> > +
> > + buck_volt = regulator_get_voltage(svsb->buck);
> > + if (buck_volt != opp_vboot) {
> > + pr_err("%s: buck voltage: %u, expected vboot: %u\n",
> > + svsb->name, buck_volt, opp_vboot);
> > + ret = -EPERM;
> > + goto init01_finish;
> > + }
> > +
> > + init_completion(&svsb->init_completion);
> > + flags = claim_mtk_svs_lock();
> > + svs_set_phase(svs, SVS_PHASE_INIT01);
> > + release_mtk_svs_lock(flags);
> > + time_left =
> > + wait_for_completion_timeout(&svsb->init_completion,
> > + msecs_to_jiffies(2000));
> > + if (time_left == 0) {
> > + pr_err("%s: init01 completion timeout\n", svsb->name);
> > + ret = -EBUSY;
> > + goto init01_finish;
> > + }
> > + }
> > +
> > +init01_finish:
> > + for (idx = 0; idx < svsp->bank_num; idx++) {
> > + svsb = &svsp->banks[idx];
> > +
> > + if (!svsb->init01_support)
> > + continue;
> > +
> > + for (i = 0; i < svsb->opp_count; i++)
> > + dev_pm_opp_enable(svsb->dev, svsb->opp_freqs[i]);
> > +
> > + if (regulator_set_mode(svsb->buck, REGULATOR_MODE_NORMAL))
> > + pr_notice("%s: fail to set normal mode: %d\n",
> > + svsb->name, ret);
> > +
> > + if (svsb->mtcmos_request) {
> > + if (pm_runtime_put_sync(svsb->dev))
> > + pr_err("%s: turn mtcmos off fail: %d\n",
> > + svsb->name, ret);
> > + pm_runtime_disable(svsb->dev);
> > + dev_pm_domain_detach(svsb->dev, 0);
> > + if (regulator_disable(svsb->buck))
> > + pr_err("%s: fail to disable %s power: %d\n",
> > + svsb->name, svsb->buck_name, ret);
> > + }
> > + }
> > +
> > + pm_qos_remove_request(&qos_request);
> > +
> > + return ret;
> > +}
> > +
> > +static int svs_start(struct mtk_svs *svs)
> > +{
> > + int ret;
> > +
> > + ret = svs_init01(svs);
> > + if (ret)
> > + return ret;
> > +
> > + ret = svs_init02(svs);
> > + if (ret)
> > + return ret;
> > +
> > + svs_mon_mode(svs);
> > +
> > + return ret;
> > +}
> > +
> > +static int svs_mt8183_efuse_parsing(struct mtk_svs *svs)
> > +{
> > + const struct svs_platform *svsp = svs->platform;
> > + struct thermal_parameter tp;
> > + struct svs_bank *svsb;
> > + bool mon_mode_support = true;
> > + int format[6], x_roomt[6], tb_roomt;
> > + u32 idx, i, ft_pgm, mts, temp0, temp1, temp2;
> > +
> > + if (svsp->fake_efuse) {
> > + pr_notice("fake efuse\n");
> > + svs->efuse[0] = 0x00310080;
> > + svs->efuse[1] = 0xabfbf757;
> > + svs->efuse[2] = 0x47c747c7;
> > + svs->efuse[3] = 0xabfbf757;
> > + svs->efuse[4] = 0xe7fca0ec;
> > + svs->efuse[5] = 0x47bf4b88;
> > + svs->efuse[6] = 0xabfb8fa5;
> > + svs->efuse[7] = 0xabfb217b;
> > + svs->efuse[8] = 0x4bf34be1;
> > + svs->efuse[9] = 0xabfb670d;
> > + svs->efuse[16] = 0xabfbc653;
> > + svs->efuse[17] = 0x47f347e1;
> > + svs->efuse[18] = 0xabfbd848;
> > +
> > + svs->thermal_efuse[0] = 0x02873f69;
> > + svs->thermal_efuse[1] = 0xa11d9142;
> > + svs->thermal_efuse[2] = 0xa2526900;
> > + }
> > +
> > + /* svs efuse parsing */
> > + ft_pgm = (svs->efuse[0] >> 4) & 0xf;
> > +
> > + for (idx = 0; idx < svsp->bank_num; idx++) {
> > + svsb = &svsp->banks[idx];
> > + if (ft_pgm <= 1)
> > + svsb->init01_volt_flag = SVS_INIT01_VOLT_IGNORE;
> > +
> > + switch (svsb->sw_id) {
> > + case SVS_CPU_LITTLE:
> > + svsb->bdes = svs->efuse[16] & 0xff;
> > + svsb->mdes = (svs->efuse[16] >> 8) & 0xff;
> > + svsb->dcbdet = (svs->efuse[16] >> 16) & 0xff;
> > + svsb->dcmdet = (svs->efuse[16] >> 24) & 0xff;
> > + svsb->mtdes = (svs->efuse[17] >> 16) & 0xff;
> > +
> > + if (ft_pgm <= 3)
> > + svsb->volt_offset += 10;
> > + else
> > + svsb->volt_offset += 2;
> > + break;
> > + case SVS_CPU_BIG:
> > + svsb->bdes = svs->efuse[18] & 0xff;
> > + svsb->mdes = (svs->efuse[18] >> 8) & 0xff;
> > + svsb->dcbdet = (svs->efuse[18] >> 16) & 0xff;
> > + svsb->dcmdet = (svs->efuse[18] >> 24) & 0xff;
> > + svsb->mtdes = svs->efuse[17] & 0xff;
> > +
> > + if (ft_pgm <= 3)
> > + svsb->volt_offset += 15;
> > + else
> > + svsb->volt_offset += 12;
> > + break;
> > + case SVS_CCI:
> > + svsb->bdes = svs->efuse[4] & 0xff;
> > + svsb->mdes = (svs->efuse[4] >> 8) & 0xff;
> > + svsb->dcbdet = (svs->efuse[4] >> 16) & 0xff;
> > + svsb->dcmdet = (svs->efuse[4] >> 24) & 0xff;
> > + svsb->mtdes = (svs->efuse[5] >> 16) & 0xff;
> > +
> > + if (ft_pgm <= 3)
> > + svsb->volt_offset += 10;
> > + else
> > + svsb->volt_offset += 2;
> > + break;
> > + case SVS_GPU:
> > + svsb->bdes = svs->efuse[6] & 0xff;
> > + svsb->mdes = (svs->efuse[6] >> 8) & 0xff;
> > + svsb->dcbdet = (svs->efuse[6] >> 16) & 0xff;
> > + svsb->dcmdet = (svs->efuse[6] >> 24) & 0xff;
> > + svsb->mtdes = svs->efuse[5] & 0xff;
> > +
> > + if (ft_pgm >= 2) {
> > + svsb->freq_base = 800000000; /* 800MHz */
> > + svsb->dvt_fixed = 2;
> > + }
> > + break;
> > + default:
> > + break;
> > + }
> > + }
> > +
> > + for (i = 0; i < svsp->efuse_num; i++) {
> > + if (svs->efuse[i])
> > + pr_notice("M_HW_RES%d: 0x%08x\n", i, svs->efuse[i]);
> > + }
> > +
> > + /* thermal efuse parsing */
> > + if (!svs->thermal_efuse)
> > + return 0;
> > +
> > + tp.adc_ge_t = (svs->thermal_efuse[1] >> 22) & 0x3ff;
> > + tp.adc_oe_t = (svs->thermal_efuse[1] >> 12) & 0x3ff;
> > +
> > + tp.o_vtsmcu1 = (svs->thermal_efuse[0] >> 17) & 0x1ff;
> > + tp.o_vtsmcu2 = (svs->thermal_efuse[0] >> 8) & 0x1ff;
> > + tp.o_vtsmcu3 = svs->thermal_efuse[1] & 0x1ff;
> > + tp.o_vtsmcu4 = (svs->thermal_efuse[2] >> 23) & 0x1ff;
> > + tp.o_vtsmcu5 = (svs->thermal_efuse[2] >> 5) & 0x1ff;
> > + tp.o_vtsabb = (svs->thermal_efuse[2] >> 14) & 0x1ff;
> > +
> > + tp.degc_cali = (svs->thermal_efuse[0] >> 1) & 0x3f;
> > + tp.adc_cali_en_t = svs->thermal_efuse[0] & BIT(0);
> > + tp.o_slope_sign = (svs->thermal_efuse[0] >> 7) & BIT(0);
> > +
> > + tp.ts_id = (svs->thermal_efuse[1] >> 9) & BIT(0);
> > + tp.o_slope = (svs->thermal_efuse[0] >> 26) & 0x3f;
> > +
> > + if (tp.adc_cali_en_t == 1) {
> > + if (tp.ts_id == 0)
> > + tp.o_slope = 0;
> > +
> > + if ((tp.adc_ge_t < 265 || tp.adc_ge_t > 758) ||
> > + (tp.adc_oe_t < 265 || tp.adc_oe_t > 758) ||
> > + (tp.o_vtsmcu1 < -8 || tp.o_vtsmcu1 > 484) ||
> > + (tp.o_vtsmcu2 < -8 || tp.o_vtsmcu2 > 484) ||
> > + (tp.o_vtsmcu3 < -8 || tp.o_vtsmcu3 > 484) ||
> > + (tp.o_vtsmcu4 < -8 || tp.o_vtsmcu4 > 484) ||
> > + (tp.o_vtsmcu5 < -8 || tp.o_vtsmcu5 > 484) ||
> > + (tp.o_vtsabb < -8 || tp.o_vtsabb > 484) ||
> > + (tp.degc_cali < 1 || tp.degc_cali > 63)) {
> > + pr_err("bad thermal efuse data. disable mon mode\n");
> > + mon_mode_support = false;
> > + }
> > + } else {
> > + pr_err("no thermal efuse data. disable mon mode\n");
> > + mon_mode_support = false;
> > + }
> > +
> > + if (!mon_mode_support) {
> > + for (i = 0; i < svsp->thermal_efuse_num; i++)
> > + pr_err("thermal_efuse[%u] = 0x%08x\n",
> > + i, svs->thermal_efuse[i]);
> > +
> > + for (idx = 0; idx < svsp->bank_num; idx++) {
> > + svsb = &svsp->banks[idx];
> > + svsb->mon_mode_support = false;
> > + }
> > +
> > + return 0;
> > + }
> > +
> > + tp.ge = ((tp.adc_ge_t - 512) * 10000) / 4096;
> > + tp.oe = (tp.adc_oe_t - 512);
> > + tp.gain = (10000 + tp.ge);
> > +
> > + format[0] = (tp.o_vtsmcu1 + 3350 - tp.oe);
> > + format[1] = (tp.o_vtsmcu2 + 3350 - tp.oe);
> > + format[2] = (tp.o_vtsmcu3 + 3350 - tp.oe);
> > + format[3] = (tp.o_vtsmcu4 + 3350 - tp.oe);
> > + format[4] = (tp.o_vtsmcu5 + 3350 - tp.oe);
> > + format[5] = (tp.o_vtsabb + 3350 - tp.oe);
> > +
> > + for (i = 0; i < 6; i++)
> > + x_roomt[i] = (((format[i] * 10000) / 4096) * 10000) / tp.gain;
> > +
> > + temp0 = (10000 * 100000 / tp.gain) * 15 / 18;
> > +
> > + if (tp.o_slope_sign == 0)
> > + mts = (temp0 * 10) / (1534 + tp.o_slope * 10);
> > + else
> > + mts = (temp0 * 10) / (1534 - tp.o_slope * 10);
> > +
> > + for (idx = 0; idx < svsp->bank_num; idx++) {
> > + svsb = &svsp->banks[idx];
> > + svsb->mts = mts;
> > +
> > + switch (svsb->sw_id) {
> > + case SVS_CPU_LITTLE:
> > + tb_roomt = x_roomt[3];
> > + break;
> > + case SVS_CPU_BIG:
> > + tb_roomt = x_roomt[4];
> > + break;
> > + case SVS_CCI:
> > + tb_roomt = x_roomt[3];
> > + break;
> > + case SVS_GPU:
> > + tb_roomt = x_roomt[1];
> > + break;
> > + default:
> > + pr_err("unknown svsb_id = %u? disable svs\n",
> > + svsb->sw_id);
> > + return -EINVAL;
> > + }
> > +
> > + temp0 = (tp.degc_cali * 10 / 2);
> > + temp1 = ((10000 * 100000 / 4096 / tp.gain) *
> > + tp.oe + tb_roomt * 10) * 15 / 18;
> > +
> > + if (tp.o_slope_sign == 0)
> > + temp2 = temp1 * 100 / (1534 + tp.o_slope * 10);
> > + else
> > + temp2 = temp1 * 100 / (1534 - tp.o_slope * 10);
> > +
> > + svsb->bts = (temp0 + temp2 - 250) * 4 / 10;
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +static int svs_is_support(struct mtk_svs *svs)
>
> nit: this appears to be a check if the platform supports SVS. If so,
> then it should probably be 'bool' and be called svs_is_supported().

bool/svs_is_supported are good ideas. I'll apply it in the next patch.
Thanks.

>
> > +{
> > + const struct svs_platform *svsp = svs->platform;
> > + struct svs_bank *svsb;
> > + struct nvmem_cell *cell;
> > + size_t len;
> > + int ret;
> > + u32 idx, i;
> > +
> > + if (svsp->fake_efuse) {
> > + len = svsp->efuse_num * 4;
> > + svs->efuse = kzalloc(len, GFP_KERNEL);
> > + if (!svs->efuse)
> > + return -ENOMEM;
> > +
> > + len = svsp->thermal_efuse_num * 4;
> > + svs->thermal_efuse = kzalloc(len, GFP_KERNEL);
> > + if (!svs->thermal_efuse)
> > + return -ENOMEM;
> > +
> > + goto svsp_efuse_parsing;
> > + }
> > +
> > + /* get svs efuse by nvmem */
> > + cell = nvmem_cell_get(svs->dev, "svs-calibration-data");
> > + if (IS_ERR(cell)) {
> > + pr_err("no \"svs-calibration-data\" from dts? disable svs\n");
> > + return PTR_ERR(cell);
> > + }
> > +
> > + svs->efuse = (u32 *)nvmem_cell_read(cell, &len);
> > + nvmem_cell_put(cell);
> > +
> > + ret = (svs->efuse[svsp->efuse_check] == 0) ? -EPERM : 0;
> > + if (ret) {
> > + pr_err("no svs efuse. disable svs.\n");
> > + for (i = 0; i < svsp->efuse_num; i++)
> > + pr_err("M_HW_RES%d: 0x%08x\n", i, svs->efuse[i]);
> > + return ret;
> > + }
> > +
> > + /* get thermal efuse by nvmem */
> > + cell = nvmem_cell_get(svs->dev, "calibration-data");
> > + if (IS_ERR(cell)) {
> > + pr_err("no \"calibration-data\" from dts? disable mon mode\n");
> > + svs->thermal_efuse = NULL;
> > + for (idx = 0; idx < svsp->bank_num; idx++) {
> > + svsb = &svsp->banks[idx];
> > + svsb->mon_mode_support = false;
> > + }
> > + goto svsp_efuse_parsing;
> > + }
> > +
> > + svs->thermal_efuse = (u32 *)nvmem_cell_read(cell, &len);
> > + nvmem_cell_put(cell);
> > +
> > +svsp_efuse_parsing:
> > + ret = svsp->efuse_parsing(svs);
> > +
> > + return ret;
> > +}
> > +
> > +static int svs_resource_setup(struct mtk_svs *svs)
> > +{
> > + const struct svs_platform *svsp = svs->platform;
> > + struct svs_bank *svsb;
> > + struct platform_device *pdev;
> > + struct device_node *np = NULL;
> > + struct dev_pm_opp *opp;
> > + unsigned long freq;
> > + size_t opp_size;
> > + int count, ret;
> > + u32 idx, i;
> > +
> > + for (idx = 0; idx < svsp->bank_num; idx++) {
> > + svsb = &svsp->banks[idx];
> > +
> > + if (!svsb->init01_support)
> > + continue;
> > +
> > + switch (svsb->sw_id) {
> > + case SVS_CPU_LITTLE:
> > + svsb->name = "SVS_CPU_LITTLE";
> > + break;
> > + case SVS_CPU_BIG:
> > + svsb->name = "SVS_CPU_BIG";
> > + break;
> > + case SVS_CCI:
> > + svsb->name = "SVS_CCI";
> > + break;
> > + case SVS_GPU:
> > + svsb->name = "SVS_GPU";
> > + break;
> > + default:
> > + WARN_ON(1);
> > + return -EINVAL;
> > + }
> > +
> > + /* Add svs_bank device for opp-table/mtcmos/buck control */
> > + pdev = platform_device_alloc(svsb->name, 0);
> > + if (!pdev) {
> > + pr_err("%s: fail to alloc pdev for svs_bank\n",
> > + svsb->name);
> > + return -ENOMEM;
> > + }
> > +
> > + for_each_child_of_node(svs->dev->of_node, np) {
> > + if (of_device_is_compatible(np, svsb->of_compatible)) {
> > + pdev->dev.of_node = np;
> > + break;
> > + }
> > + }
> > +
> > + ret = platform_device_add(pdev);
> > + if (ret) {
> > + pr_err("%s: fail to add svs_bank device: %d\n",
> > + svsb->name, ret);
> > + return ret;
> > + }
> > +
> > + svsb->dev = &pdev->dev;
> > + dev_set_drvdata(svsb->dev, svs);
> > + ret = dev_pm_opp_of_add_table(svsb->dev);
> > + if (ret) {
> > + pr_err("%s: fail to add opp table: %d\n",
> > + svsb->name, ret);
> > + return ret;
> > + }
> > +
> > + mutex_init(&svsb->lock);
> > +
> > + svsb->buck = devm_regulator_get_optional(svsb->dev,
> > + svsb->buck_name);
> > + if (IS_ERR(svsb->buck)) {
> > + pr_err("%s: cannot get regulator \"%s-supply\"\n",
> > + svsb->name, svsb->buck_name);
> > + return PTR_ERR(svsb->buck);
> > + }
> > +
> > + count = dev_pm_opp_get_opp_count(svsb->dev);
> > + if (svsb->opp_count != count) {
> > + pr_err("%s: opp_count not \"%u\" but get \"%d\"?\n",
> > + svsb->name, svsb->opp_count, count);
> > + return count;
> > + }
> > +
> > + opp_size = 4 * svsb->opp_count;
> > + svsb->opp_volts = kmalloc(opp_size, GFP_KERNEL);
> > + if (!svsb->opp_volts)
> > + return -ENOMEM;
> > +
> > + svsb->init02_volts = kmalloc(opp_size, GFP_KERNEL);
> > + if (!svsb->init02_volts)
> > + return -ENOMEM;
> > +
> > + svsb->volts = kmalloc(opp_size, GFP_KERNEL);
> > + if (!svsb->volts)
> > + return -ENOMEM;
> > +
> > + svsb->opp_freqs = kmalloc(opp_size, GFP_KERNEL);
> > + if (!svsb->opp_freqs)
> > + return -ENOMEM;
> > +
> > + svsb->freqs_pct = kmalloc(opp_size, GFP_KERNEL);
> > + if (!svsb->freqs_pct)
> > + return -ENOMEM;
> > +
> > + for (i = 0, freq = (u32)-1; i < svsb->opp_count; i++, freq--) {
> > + opp = dev_pm_opp_find_freq_floor(svsb->dev, &freq);
> > + if (IS_ERR(opp)) {
> > + pr_err("%s: error opp entry!!, err = %ld\n",
> > + svsb->name, PTR_ERR(opp));
> > + return PTR_ERR(opp);
> > + }
> > +
> > + svsb->opp_freqs[i] = freq;
> > + svsb->opp_volts[i] = dev_pm_opp_get_voltage(opp);
> > + svsb->freqs_pct[i] = percent(svsb->opp_freqs[i],
> > + svsb->freq_base) & 0xff;
> > + }
> > + }
> > +
> > + return 0;
> > +}
>
> There are lots of resources (platform_device, all the kmalloc regions)
> that are never free'd here. You might consider using devm for this.
>
> Related, all the small malloc's are calculated based on the opp_count
> for each bank, but they are all hard-coded to 16. Seems it would be
> better to have a default/max size for this in the bank structure itself
> instead of making these small allocations.

Thanks for the advices. The default/max size are good ideas. I'll apply
it in the next patch.

>
> > +static int svs_suspend(struct device *dev)
> > +{
> > + struct mtk_svs *svs = dev_get_drvdata(dev);
> > + const struct svs_platform *svsp = svs->platform;
> > + struct svs_bank *svsb;
> > + unsigned long flags;
> > + u32 idx;
> > +
> > + /* Wait if there is processing svs_isr(). Suspend all banks. */
> > + flags = claim_mtk_svs_lock();
> > + for (idx = 0; idx < svsp->bank_num; idx++) {
> > + svsb = &svsp->banks[idx];
> > + svs->bank = svsb;
> > + svs_switch_bank(svs);
> > + svs_writel(svs, 0x0, SVSEN);
> > + svs_writel(svs, 0x00ffffff, INTSTS);
>
> I'm assuming this part will disable future interrupts?
Yes, this for-loop will disable all the SVS banks' interrupts.

> I'm not seeing where they get re-enabled on the resume path.
In the svs_resume(), we re-run svs_init02() to enable each SVS bank.

>
>
> > + svsb->suspended = true;
> > + }
> > + release_mtk_svs_lock(flags);
> > +
> > + for (idx = 0; idx < svsp->bank_num; idx++) {
> > + svsb = &svsp->banks[idx];
> > + if (svsb->phase == SVS_PHASE_MON) {
> > + svsb->phase = SVS_PHASE_INIT02;
> > + svs_set_volts(svsb, true);
> > + }
> > + }
> > +
> > + clk_disable_unprepare(svs->main_clk);
> > +
> > + return 0;
> > +}
> > +
> > +static int svs_resume(struct device *dev)
> > +{
> > + struct mtk_svs *svs = dev_get_drvdata(dev);
> > + const struct svs_platform *svsp = svs->platform;
> > + struct svs_bank *svsb;
> > + int ret;
> > + u32 idx;
> > +
> > + ret = clk_prepare_enable(svs->main_clk);
> > + if (ret)
> > + pr_err("%s(): cannot enable main_clk\n", __func__);
> > +
> > + for (idx = 0; idx < svsp->bank_num; idx++) {
> > + svsb = &svsp->banks[idx];
> > + svsb->suspended = false;
> > + }
> > +
> > + ret = svs_init02(svs);
> > + if (ret)
> > + return ret;
> > +
> > + svs_mon_mode(svs);
> > +
> > + return 0;
> > +}
>
> Kevin

2020-01-13 07:05:10

by Nicolas Boichat

[permalink] [raw]

Subject: Re: [PATCH v5 1/3] dt-bindings: soc: add mtk svs dt-bindings

On Fri, Dec 27, 2019 at 2:51 PM Roger Lu <[email protected]> wrote:
>
> Dear Rob,
>
> Sorry for the late reply.
>
> On Mon, 2019-09-30 at 08:35 -0500, Rob Herring wrote:
> > On Fri, Sep 06, 2019 at 06:05:13PM +0800, Roger Lu wrote:
> > > Document the binding for enabling mtk svs on MediaTek SoC.
> > >
> > > Signed-off-by: Roger Lu <[email protected]>
> > > ---
> > > .../devicetree/bindings/power/mtk-svs.txt | 88 +++++++++++++++++++
> > > 1 file changed, 88 insertions(+)
> > > create mode 100644 Documentation/devicetree/bindings/power/mtk-svs.txt
> > >
> > > diff --git a/Documentation/devicetree/bindings/power/mtk-svs.txt b/Documentation/devicetree/bindings/power/mtk-svs.txt
> > > new file mode 100644
> > > index 000000000000..6a71992ef162
> > > --- /dev/null
> > > +++ b/Documentation/devicetree/bindings/power/mtk-svs.txt
> > > @@ -0,0 +1,88 @@
> > > +* Mediatek Smart Voltage Scaling (MTK SVS)
> > > +
> > > +This describes the device tree binding for the MTK SVS controller (bank)
> > > +which helps provide the optimized CPU/GPU/CCI voltages. This device also
> > > +needs thermal data to calculate thermal slope for accurately compensate
> > > +the voltages when temperature change.
> > > +
> > > +Required properties:
> > > +- compatible:
> > > + - "mediatek,mt8183-svs" : For MT8183 family of SoCs
> > > +- reg: Address range of the MTK SVS controller.
> > > +- interrupts: IRQ for the MTK SVS controller.
> > > +- clocks, clock-names: Clocks needed for the svs controller. required
> > > + clocks are:
> > > + "main_clk": Main clock needed for register access
> >
> > '_clk' is redundant.
>
> Oh Okay. I'll remove _clk. Thanks.
>
> >
> > > +- nvmem-cells: Phandle to the calibration data provided by a nvmem device.
> > > +- nvmem-cell-names: Should be "svs-calibration-data" and "calibration-data"
> > > +
> > > +Subnodes:
> > > +- svs_cpu_little: SVS bank device node of little CPU
> > > + compatible: "mediatek,mt8183-svs-cpu-little"
> > > + operating-points-v2: OPP table hooked by SVS little CPU bank.
> > > + SVS will optimze this OPP table voltage part.
> > > + vcpu-little-supply: PMIC buck of little CPU
> > > +- svs_cpu_big: SVS bank device node of big CPU
> > > + compatible: "mediatek,mt8183-svs-cpu-big"
> > > + operating-points-v2: OPP table hooked by SVS big CPU bank.
> > > + SVS will optimze this OPP table voltage part.
> > > + vcpu-big-supply: PMIC buck of big CPU
> > > +- svs_cci: SVS bank device node of CCI
> > > + compatible: "mediatek,mt8183-svs-cci"
> > > + operating-points-v2: OPP table hooked by SVS CCI bank.
> > > + SVS will optimze this OPP table voltage part.
> > > + vcci-supply: PMIC buck of CCI
> > > +- svs_gpu: SVS bank device node of GPU
> > > + compatible: "mediatek,mt8183-svs-gpu"
> > > + operating-points-v2: OPP table hooked by SVS GPU bank.
> > > + SVS will optimze this OPP table voltage part.
> > > + vgpu-spply: PMIC buck of GPU
> > > +
> > > +Example:
> > > +
> > > + svs: svs@1100b000 {
> > > + compatible = "mediatek,mt8183-svs";
> > > + reg = <0 0x1100b000 0 0x1000>;
> > > + interrupts = <GIC_SPI 127 IRQ_TYPE_LEVEL_LOW 0>;
> >
> > GIC interrupts are 3 cells, you have 4.
>
> Oops, I'll remove the fourth parameter. Thanks a lot.
>
> >
> > > + clocks = <&infracfg CLK_INFRA_THERM>;
> > > + clock-names = "main_clk";
> > > + nvmem-cells = <&svs_calibration>, <&thermal_calibration>;
> > > + nvmem-cell-names = "svs-calibration-data", "calibration-data";
> > > +
> > > + svs_cpu_little: svs_cpu_little {
> >
> > Don't use '_' in node names.
>
> Okay. I'll replace it with '-'. Thanks.
>
> >
> > > + compatible = "mediatek,mt8183-svs-cpu-little";
> > > + operating-points-v2 = <&cluster0_opp>;
> > > + };
> > > +
> > > + svs_cpu_big: svs_cpu_big {
> > > + compatible = "mediatek,mt8183-svs-cpu-big";
> > > + operating-points-v2 = <&cluster1_opp>;
> > > + };
> > > +
> > > + svs_cci: svs_cci {
> > > + compatible = "mediatek,mt8183-svs-cci";
> > > + operating-points-v2 = <&cci_opp>;
> > > + };
> > > +
> > > + svs_gpu: svs_gpu {
> > > + compatible = "mediatek,mt8183-svs-gpu";
> > > + power-domains = <&scpsys MT8183_POWER_DOMAIN_MFG_2D>;
> > > + operating-points-v2 = <&gpu_opp_table>;
> > > + };
> > > + };
> > > +
> > > + &svs_cpu_little {
> > > + vcpu-little-supply = <&mt6358_vproc12_reg>;
> >
> > It's already defined to have OPP and supply in the cpu nodes. Parse them
> > to get this information rather than duplicating it here.
> >
> > The same should apply to the CCI and GPU.
>
> Please let me explain the reason why I add SVS sub-nodes. I ever try to
> parse other nodes to get desired power-domains/OPP table. However, it
> makes SVS driver harder to develop and maintain.
>
> 1. When a SVS-controller-init wants GPU_CORE0's OPP table in one node
> but it needs power-domains(GPU_MFG_2D) in another node, it becomes
> complicated and confusing when SVS sub-node tries to parse many nodes.
> Therefore, we want SVS sub-node to focus on what SVS bank requires by
> how we do in this patch.
>
> 2. In hardware point of view, SVS controller depends on other hardware's
> power only. All the SVS controller registers are in SVS hardware. So, we
> think It's good that SVS sub-node describes what SVS controller requires
> instead of linking other subsys nodes and parse the property that SVS
> controller needs.
>
> 3. We want SVS driver to have a generic way to attain subsys device for
> using "pm_runtime and OPP framework" API. If SVS driver tries to parse
> CPU(little/big core) and other subsys device node(e.g cci/gpu), it means
> SVS driver has to maintain different methodologies(cpu-specific?
> devfreq? others?) in order to get CPU(little/big core) and other subsys
> device(e.g cci/gpu) for using "pm_runtime and OPP framework" API.

(Didn't see this more complete reply before replying to v6, I can see
your argument, but if we wanted to push further to have the sub-device
node in the DT)

From what I see, the SVS driver for node x (cpu/cci/gpu) requires only 3 things:
- An OPP table => that should always be "operating-points-v2"
property of the node x.
- A power domain => that should always be power-domains property of node x.
- A regulator. That one is a bit tricky as the cpu/cci uses "proc",
but gpu uses "mali" (at least on 8183). But maybe you can add a
child-regulator-name property or something to the DT so that the SVS
driver can find the correct regulator?

Seems like the solution could be quite generic?

> >
> > Rob
>
> Sincerely,
> Roger Lu.