| Message ID | 1527152242-31281-2-git-send-email-ilialin@codeaurora.org (mailing list archive) |
|---|---|
| State | Changes Requested, archived |
| Headers | show |
Hi Ilia, On 24/05/18 09:57, Ilia Lin wrote: > In Certain QCOM SoCs like apq8096 and msm8996 that have KRYO processors, > the CPU frequency subset and voltage value of each OPP varies > based on the silicon variant in use. Qualcomm Process Voltage Scaling Tables > defines the voltage and frequency value based on the msm-id in SMEM > and speedbin blown in the efuse combination. > The qcom-cpufreq-kryo driver reads the msm-id and efuse value from the SoC > to provide the OPP framework with required information. > This is used to determine the voltage and frequency value for each OPP of > operating-points-v2 table when it is parsed by the OPP framework. > > Signed-off-by: Ilia Lin <ilialin@codeaurora.org> > --- > drivers/cpufreq/Kconfig.arm | 10 ++ > drivers/cpufreq/Makefile | 1 + > drivers/cpufreq/cpufreq-dt-platdev.c | 3 + > drivers/cpufreq/qcom-cpufreq-kryo.c | 194 +++++++++++++++++++++++++++++++++++ > 4 files changed, 208 insertions(+) > create mode 100644 drivers/cpufreq/qcom-cpufreq-kryo.c > > diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm > index de55c7d..0bfd40e 100644 > --- a/drivers/cpufreq/Kconfig.arm > +++ b/drivers/cpufreq/Kconfig.arm > @@ -124,6 +124,16 @@ config ARM_OMAP2PLUS_CPUFREQ > depends on ARCH_OMAP2PLUS > default ARCH_OMAP2PLUS > > +config ARM_QCOM_CPUFREQ_KRYO > + bool "Qualcomm Kryo based CPUFreq" > + depends on QCOM_QFPROM > + depends on QCOM_SMEM > + select PM_OPP > + help > + This adds the CPUFreq driver for Qualcomm Kryo SoC based boards. > + > + If in doubt, say N. > + > config ARM_S3C_CPUFREQ > bool > help > diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile > index 8d24ade..fb4a2ec 100644 > --- a/drivers/cpufreq/Makefile > +++ b/drivers/cpufreq/Makefile > @@ -65,6 +65,7 @@ obj-$(CONFIG_MACH_MVEBU_V7) += mvebu-cpufreq.o > obj-$(CONFIG_ARM_OMAP2PLUS_CPUFREQ) += omap-cpufreq.o > obj-$(CONFIG_ARM_PXA2xx_CPUFREQ) += pxa2xx-cpufreq.o > obj-$(CONFIG_PXA3xx) += pxa3xx-cpufreq.o > +obj-$(CONFIG_ARM_QCOM_CPUFREQ_KRYO) += qcom-cpufreq-kryo.o > obj-$(CONFIG_ARM_S3C2410_CPUFREQ) += s3c2410-cpufreq.o > obj-$(CONFIG_ARM_S3C2412_CPUFREQ) += s3c2412-cpufreq.o > obj-$(CONFIG_ARM_S3C2416_CPUFREQ) += s3c2416-cpufreq.o > diff --git a/drivers/cpufreq/cpufreq-dt-platdev.c b/drivers/cpufreq/cpufreq-dt-platdev.c > index 3b585e4..77d6ab8 100644 > --- a/drivers/cpufreq/cpufreq-dt-platdev.c > +++ b/drivers/cpufreq/cpufreq-dt-platdev.c > @@ -118,6 +118,9 @@ > > { .compatible = "nvidia,tegra124", }, > > + { .compatible = "qcom,apq8096", }, > + { .compatible = "qcom,msm8996", }, > + > { .compatible = "st,stih407", }, > { .compatible = "st,stih410", }, > > diff --git a/drivers/cpufreq/qcom-cpufreq-kryo.c b/drivers/cpufreq/qcom-cpufreq-kryo.c > new file mode 100644 > index 0000000..9fe379c > --- /dev/null > +++ b/drivers/cpufreq/qcom-cpufreq-kryo.c > @@ -0,0 +1,194 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Copyright (c) 2018, The Linux Foundation. All rights reserved. > + */ > + > +/* > + * In Certain QCOM SoCs like apq8096 and msm8996 that have KRYO processors, > + * the CPU frequency subset and voltage value of each OPP varies > + * based on the silicon variant in use. Qualcomm Process Voltage Scaling Tables > + * defines the voltage and frequency value based on the msm-id in SMEM > + * and speedbin blown in the efuse combination. > + * The qcom-cpufreq-kryo driver reads the msm-id and efuse value from the SoC > + * to provide the OPP framework with required information. > + * This is used to determine the voltage and frequency value for each OPP of > + * operating-points-v2 table when it is parsed by the OPP framework. > + */ > + > +#include <linux/cpu.h> > +#include <linux/err.h> > +#include <linux/init.h> > +#include <linux/kernel.h> > +#include <linux/module.h> > +#include <linux/nvmem-consumer.h> > +#include <linux/of.h> > +#include <linux/platform_device.h> > +#include <linux/pm_opp.h> > +#include <linux/slab.h> > +#include <linux/soc/qcom/smem.h> > + > +#define MSM_ID_SMEM 137 > + > +enum _msm_id { > + MSM8996V3 = 0xF6ul, > + APQ8096V3 = 0x123ul, > + MSM8996SG = 0x131ul, > + APQ8096SG = 0x138ul, > +}; > + > +enum _msm8996_version { > + MSM8996_V3, > + MSM8996_SG, > + NUM_OF_MSM8996_VERSIONS, > +}; > + > +static enum _msm8996_version __init qcom_cpufreq_kryo_get_msm_id(void) > +{ > + size_t len; > + u32 *msm_id; > + enum _msm8996_version version; > + > + msm_id = qcom_smem_get(QCOM_SMEM_HOST_ANY, MSM_ID_SMEM, &len); > + /* The first 4 bytes are format, next to them is the actual msm-id */ > + msm_id++; > + > + switch ((enum _msm_id)*msm_id) { > + case MSM8996V3: > + case APQ8096V3: > + version = MSM8996_V3; > + break; > + case MSM8996SG: > + case APQ8096SG: > + version = MSM8996_SG; > + break; > + default: > + version = NUM_OF_MSM8996_VERSIONS; > + } > + > + return version; > +} > + > +static int qcom_cpufreq_kryo_probe(struct platform_device *pdev) > +{ > + struct opp_table *opp_tables[NR_CPUS] = {0}; > + struct platform_device *cpufreq_dt_pdev; > + enum _msm8996_version msm8996_version; > + struct nvmem_cell *speedbin_nvmem; > + struct device_node *np; > + struct device *cpu_dev; > + unsigned cpu; > + u8 *speedbin; > + u32 versions; > + size_t len; > + int ret; > + > + cpu_dev = get_cpu_device(0); > + if (NULL == cpu_dev) > + return -ENODEV; > + > + msm8996_version = qcom_cpufreq_kryo_get_msm_id(); > + if (NUM_OF_MSM8996_VERSIONS == msm8996_version) { > + dev_err(cpu_dev, "Not Snapdragon 820/821!"); > + return -ENODEV; > + } > + > + np = dev_pm_opp_of_get_opp_desc_node(cpu_dev); > + if (IS_ERR(np)) > + return PTR_ERR(np); > + > + if (!of_device_is_compatible(np, "operating-points-v2-kryo-cpu")) { > + of_node_put(np); > + return -ENOENT; > + } > + > + speedbin_nvmem = of_nvmem_cell_get(np, NULL); > + of_node_put(np); > + if (IS_ERR(speedbin_nvmem)) { > + dev_err(cpu_dev, "Could not get nvmem cell: %ld\n", > + PTR_ERR(speedbin_nvmem)); > + return PTR_ERR(speedbin_nvmem); > + } > + > + speedbin = nvmem_cell_read(speedbin_nvmem, &len); > + nvmem_cell_put(speedbin_nvmem); > + > + switch (msm8996_version) { > + case MSM8996_V3: > + versions = 1 << (unsigned int)(*speedbin); > + break; > + case MSM8996_SG: > + versions = 1 << ((unsigned int)(*speedbin) + 4); > + break; > + default: > + BUG(); > + break; > + } > + > + for_each_possible_cpu(cpu) { > + cpu_dev = get_cpu_device(cpu); > + if (NULL == cpu_dev) { > + ret = -ENODEV; > + goto free_opp; > + } > + > + opp_tables[cpu] = dev_pm_opp_set_supported_hw(cpu_dev, > + &versions, 1); > + if (IS_ERR(opp_tables[cpu])) { > + ret = PTR_ERR(opp_tables[cpu]); > + dev_err(cpu_dev, "Failed to set supported hardware\n"); > + goto free_opp; > + } > + } > + > + cpufreq_dt_pdev = platform_device_register_simple("cpufreq-dt", -1, > + NULL, 0); > + if (!IS_ERR(cpufreq_dt_pdev)) > + return 0; > + > + ret = PTR_ERR(cpufreq_dt_pdev); > + dev_err(cpu_dev, "Failed to register platform device\n"); > + > +free_opp: > + for_each_possible_cpu(cpu) { > + if (IS_ERR_OR_NULL(opp_tables[cpu])) > + break; > + dev_pm_opp_put_supported_hw(opp_tables[cpu]); > + } > + > + return ret; > +} > + > +static struct platform_driver qcom_cpufreq_kryo_driver = { > + .probe = qcom_cpufreq_kryo_probe, > + .driver = { > + .name = "qcom-cpufreq-kryo", > + }, > +}; > + > +/* > + * Since the driver depends on smem and nvmem drivers, which may > + * return EPROBE_DEFER, all the real activity is done in the probe, > + * which may be defered as well. The init here is only registering > + * the driver and the platform device. > + */ > +static int __init qcom_cpufreq_kryo_init(void) > +{ > + int ret; > + > + ret = platform_driver_register(&qcom_cpufreq_kryo_driver); > + if (unlikely(ret < 0)) > + return ret; > + > + ret = PTR_ERR_OR_ZERO(platform_device_register_simple( > + "qcom-cpufreq-kryo", -1, NULL, 0)); You simply can't do this unconditionally here. This will blow up on platforms where this driver is not supposed to work. The probe will be called on non-QCOM or non-Kryo QCOM platforms and I reckon it will crash trying to execute something in qcom_smem_get.
> -----Original Message----- > From: Sudeep Holla <sudeep.holla@arm.com> > Sent: Thursday, May 24, 2018 15:52 > To: Ilia Lin <ilialin@codeaurora.org>; vireshk@kernel.org; nm@ti.com; > sboyd@kernel.org; robh@kernel.org; mark.rutland@arm.com; > rjw@rjwysocki.net > Cc: Sudeep Holla <sudeep.holla@arm.com>; linux-pm@vger.kernel.org; > devicetree@vger.kernel.org; linux-kernel@vger.kernel.org > Subject: Re: [PATCH v12 1/2] cpufreq: Add Kryo CPU scaling driver > > Hi Ilia, > > > On 24/05/18 09:57, Ilia Lin wrote: > > In Certain QCOM SoCs like apq8096 and msm8996 that have KRYO > > processors, the CPU frequency subset and voltage value of each OPP > > varies based on the silicon variant in use. Qualcomm Process Voltage > > Scaling Tables defines the voltage and frequency value based on the > > msm-id in SMEM and speedbin blown in the efuse combination. > > The qcom-cpufreq-kryo driver reads the msm-id and efuse value from the > > SoC to provide the OPP framework with required information. > > This is used to determine the voltage and frequency value for each OPP > > of > > operating-points-v2 table when it is parsed by the OPP framework. > > > > Signed-off-by: Ilia Lin <ilialin@codeaurora.org> > > --- > > drivers/cpufreq/Kconfig.arm | 10 ++ > > drivers/cpufreq/Makefile | 1 + > > drivers/cpufreq/cpufreq-dt-platdev.c | 3 + > > drivers/cpufreq/qcom-cpufreq-kryo.c | 194 > > +++++++++++++++++++++++++++++++++++ > > 4 files changed, 208 insertions(+) > > create mode 100644 drivers/cpufreq/qcom-cpufreq-kryo.c > > > > diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm > > index de55c7d..0bfd40e 100644 > > --- a/drivers/cpufreq/Kconfig.arm > > +++ b/drivers/cpufreq/Kconfig.arm > > @@ -124,6 +124,16 @@ config ARM_OMAP2PLUS_CPUFREQ > > depends on ARCH_OMAP2PLUS > > default ARCH_OMAP2PLUS > > > > +config ARM_QCOM_CPUFREQ_KRYO > > + bool "Qualcomm Kryo based CPUFreq" > > + depends on QCOM_QFPROM > > + depends on QCOM_SMEM > > + select PM_OPP > > + help > > + This adds the CPUFreq driver for Qualcomm Kryo SoC based boards. > > + > > + If in doubt, say N. > > + > > config ARM_S3C_CPUFREQ > > bool > > help > > diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile index > > 8d24ade..fb4a2ec 100644 > > --- a/drivers/cpufreq/Makefile > > +++ b/drivers/cpufreq/Makefile > > @@ -65,6 +65,7 @@ obj-$(CONFIG_MACH_MVEBU_V7) += > mvebu-cpufreq.o > > obj-$(CONFIG_ARM_OMAP2PLUS_CPUFREQ) += omap-cpufreq.o > > obj-$(CONFIG_ARM_PXA2xx_CPUFREQ) += pxa2xx-cpufreq.o > > obj-$(CONFIG_PXA3xx) += pxa3xx-cpufreq.o > > +obj-$(CONFIG_ARM_QCOM_CPUFREQ_KRYO) += qcom-cpufreq- > kryo.o > > obj-$(CONFIG_ARM_S3C2410_CPUFREQ) += s3c2410-cpufreq.o > > obj-$(CONFIG_ARM_S3C2412_CPUFREQ) += s3c2412-cpufreq.o > > obj-$(CONFIG_ARM_S3C2416_CPUFREQ) += s3c2416-cpufreq.o > > diff --git a/drivers/cpufreq/cpufreq-dt-platdev.c > > b/drivers/cpufreq/cpufreq-dt-platdev.c > > index 3b585e4..77d6ab8 100644 > > --- a/drivers/cpufreq/cpufreq-dt-platdev.c > > +++ b/drivers/cpufreq/cpufreq-dt-platdev.c > > @@ -118,6 +118,9 @@ > > > > { .compatible = "nvidia,tegra124", }, > > > > + { .compatible = "qcom,apq8096", }, > > + { .compatible = "qcom,msm8996", }, > > + > > { .compatible = "st,stih407", }, > > { .compatible = "st,stih410", }, > > > > diff --git a/drivers/cpufreq/qcom-cpufreq-kryo.c > > b/drivers/cpufreq/qcom-cpufreq-kryo.c > > new file mode 100644 > > index 0000000..9fe379c > > --- /dev/null > > +++ b/drivers/cpufreq/qcom-cpufreq-kryo.c > > @@ -0,0 +1,194 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > +/* > > + * Copyright (c) 2018, The Linux Foundation. All rights reserved. > > + */ > > + > > +/* > > + * In Certain QCOM SoCs like apq8096 and msm8996 that have KRYO > > +processors, > > + * the CPU frequency subset and voltage value of each OPP varies > > + * based on the silicon variant in use. Qualcomm Process Voltage > > +Scaling Tables > > + * defines the voltage and frequency value based on the msm-id in > > +SMEM > > + * and speedbin blown in the efuse combination. > > + * The qcom-cpufreq-kryo driver reads the msm-id and efuse value from > > +the SoC > > + * to provide the OPP framework with required information. > > + * This is used to determine the voltage and frequency value for each > > +OPP of > > + * operating-points-v2 table when it is parsed by the OPP framework. > > + */ > > + > > +#include <linux/cpu.h> > > +#include <linux/err.h> > > +#include <linux/init.h> > > +#include <linux/kernel.h> > > +#include <linux/module.h> > > +#include <linux/nvmem-consumer.h> > > +#include <linux/of.h> > > +#include <linux/platform_device.h> > > +#include <linux/pm_opp.h> > > +#include <linux/slab.h> > > +#include <linux/soc/qcom/smem.h> > > + > > +#define MSM_ID_SMEM 137 > > + > > +enum _msm_id { > > + MSM8996V3 = 0xF6ul, > > + APQ8096V3 = 0x123ul, > > + MSM8996SG = 0x131ul, > > + APQ8096SG = 0x138ul, > > +}; > > + > > +enum _msm8996_version { > > + MSM8996_V3, > > + MSM8996_SG, > > + NUM_OF_MSM8996_VERSIONS, > > +}; > > + > > +static enum _msm8996_version __init > > +qcom_cpufreq_kryo_get_msm_id(void) > > +{ > > + size_t len; > > + u32 *msm_id; > > + enum _msm8996_version version; > > + > > + msm_id = qcom_smem_get(QCOM_SMEM_HOST_ANY, > MSM_ID_SMEM, &len); > > + /* The first 4 bytes are format, next to them is the actual msm-id */ > > + msm_id++; > > + > > + switch ((enum _msm_id)*msm_id) { > > + case MSM8996V3: > > + case APQ8096V3: > > + version = MSM8996_V3; > > + break; > > + case MSM8996SG: > > + case APQ8096SG: > > + version = MSM8996_SG; > > + break; > > + default: > > + version = NUM_OF_MSM8996_VERSIONS; > > + } > > + > > + return version; > > +} > > + > > +static int qcom_cpufreq_kryo_probe(struct platform_device *pdev) { > > + struct opp_table *opp_tables[NR_CPUS] = {0}; > > + struct platform_device *cpufreq_dt_pdev; > > + enum _msm8996_version msm8996_version; > > + struct nvmem_cell *speedbin_nvmem; > > + struct device_node *np; > > + struct device *cpu_dev; > > + unsigned cpu; > > + u8 *speedbin; > > + u32 versions; > > + size_t len; > > + int ret; > > + > > + cpu_dev = get_cpu_device(0); > > + if (NULL == cpu_dev) > > + return -ENODEV; > > + > > + msm8996_version = qcom_cpufreq_kryo_get_msm_id(); > > + if (NUM_OF_MSM8996_VERSIONS == msm8996_version) { > > + dev_err(cpu_dev, "Not Snapdragon 820/821!"); > > + return -ENODEV; > > + } > > + > > + np = dev_pm_opp_of_get_opp_desc_node(cpu_dev); > > + if (IS_ERR(np)) > > + return PTR_ERR(np); > > + > > + if (!of_device_is_compatible(np, "operating-points-v2-kryo-cpu")) { > > + of_node_put(np); > > + return -ENOENT; > > + } > > + > > + speedbin_nvmem = of_nvmem_cell_get(np, NULL); > > + of_node_put(np); > > + if (IS_ERR(speedbin_nvmem)) { > > + dev_err(cpu_dev, "Could not get nvmem cell: %ld\n", > > + PTR_ERR(speedbin_nvmem)); > > + return PTR_ERR(speedbin_nvmem); > > + } > > + > > + speedbin = nvmem_cell_read(speedbin_nvmem, &len); > > + nvmem_cell_put(speedbin_nvmem); > > + > > + switch (msm8996_version) { > > + case MSM8996_V3: > > + versions = 1 << (unsigned int)(*speedbin); > > + break; > > + case MSM8996_SG: > > + versions = 1 << ((unsigned int)(*speedbin) + 4); > > + break; > > + default: > > + BUG(); > > + break; > > + } > > + > > + for_each_possible_cpu(cpu) { > > + cpu_dev = get_cpu_device(cpu); > > + if (NULL == cpu_dev) { > > + ret = -ENODEV; > > + goto free_opp; > > + } > > + > > + opp_tables[cpu] = > dev_pm_opp_set_supported_hw(cpu_dev, > > + &versions, 1); > > + if (IS_ERR(opp_tables[cpu])) { > > + ret = PTR_ERR(opp_tables[cpu]); > > + dev_err(cpu_dev, "Failed to set supported > hardware\n"); > > + goto free_opp; > > + } > > + } > > + > > + cpufreq_dt_pdev = platform_device_register_simple("cpufreq-dt", - > 1, > > + NULL, 0); > > + if (!IS_ERR(cpufreq_dt_pdev)) > > + return 0; > > + > > + ret = PTR_ERR(cpufreq_dt_pdev); > > + dev_err(cpu_dev, "Failed to register platform device\n"); > > + > > +free_opp: > > + for_each_possible_cpu(cpu) { > > + if (IS_ERR_OR_NULL(opp_tables[cpu])) > > + break; > > + dev_pm_opp_put_supported_hw(opp_tables[cpu]); > > + } > > + > > + return ret; > > +} > > + > > +static struct platform_driver qcom_cpufreq_kryo_driver = { > > + .probe = qcom_cpufreq_kryo_probe, > > + .driver = { > > + .name = "qcom-cpufreq-kryo", > > + }, > > +}; > > + > > +/* > > + * Since the driver depends on smem and nvmem drivers, which may > > + * return EPROBE_DEFER, all the real activity is done in the probe, > > + * which may be defered as well. The init here is only registering > > + * the driver and the platform device. > > + */ > > +static int __init qcom_cpufreq_kryo_init(void) { > > + int ret; > > + > > + ret = platform_driver_register(&qcom_cpufreq_kryo_driver); > > + if (unlikely(ret < 0)) > > + return ret; > > + > > + ret = PTR_ERR_OR_ZERO(platform_device_register_simple( > > + "qcom-cpufreq-kryo", -1, NULL, 0)); > > > You simply can't do this unconditionally here. This will blow up on platforms > where this driver is not supposed to work. The probe will be called on non- > QCOM or non-Kryo QCOM platforms and I reckon it will crash trying to > execute something in qcom_smem_get. What do you mean by 'unconditionally'? The driver depends on the smem and nvmem drivers, which depend on ARCH_QCOM: + depends on QCOM_QFPROM + depends on QCOM_SMEM And if SMEM read in the probe returns something other than Kryo, it will exit. > > -- > Regards, > Sudeep
On 24/05/18 14:03, ilialin@codeaurora.org wrote: > > [...] >>> + >>> + ret = PTR_ERR_OR_ZERO(platform_device_register_simple( >>> + "qcom-cpufreq-kryo", -1, NULL, 0)); >> >> >> You simply can't do this unconditionally here. This will blow up on platforms >> where this driver is not supposed to work. The probe will be called on non- >> QCOM or non-Kryo QCOM platforms and I reckon it will crash trying to >> execute something in qcom_smem_get. > > What do you mean by 'unconditionally'? Why should you even add/register a device "qcom-cpufreq-kryo" on other platforms. Drivers can get registered, but only devices that are present or required by the platform need to be registered. > The driver depends on the smem and nvmem drivers, which depend on ARCH_QCOM: > + depends on QCOM_QFPROM > + depends on QCOM_SMEM > Sure, but we have something called single image for all ARM64 platforms. May be QCOM still used to tweeking config to build binary for your particular mobile platform but the distro kernel need single binary to work on all platforms. We have moved far away from platform specific builds long back now IIRC. > And if SMEM read in the probe returns something other than Kryo, it will exit. > Check what this driver does ? msm_id = qcom_smem_get(QCOM_SMEM_HOST_ANY, MSM_ID_SMEM, &len); msm_id++; switch ((enum _msm_id)*msm_id) I think it *will and should* crash here ? You need to check the return value for sure. But since qcom_smem_get return -EPROBE_DEFER, we keep retrying even on non QCOM platforms which is something I would like to avoid. Therefore that's not the main concern. Why do I have to see "qcom-cpufreq-kryo" device registered on my non QCOM platform ?
Thank you for the explanation. However, could you suggest, which condition should I check then? Device tree? > -----Original Message----- > From: Sudeep Holla <sudeep.holla@arm.com> > Sent: Thursday, May 24, 2018 17:01 > To: ilialin@codeaurora.org; vireshk@kernel.org; nm@ti.com; > sboyd@kernel.org; robh@kernel.org; mark.rutland@arm.com; > rjw@rjwysocki.net > Cc: Sudeep Holla <sudeep.holla@arm.com>; linux-pm@vger.kernel.org; > devicetree@vger.kernel.org; linux-kernel@vger.kernel.org > Subject: Re: [PATCH v12 1/2] cpufreq: Add Kryo CPU scaling driver > > > > On 24/05/18 14:03, ilialin@codeaurora.org wrote: > > > > > > [...] > > >>> + > >>> + ret = PTR_ERR_OR_ZERO(platform_device_register_simple( > >>> + "qcom-cpufreq-kryo", -1, NULL, 0)); > >> > >> > >> You simply can't do this unconditionally here. This will blow up on > >> platforms where this driver is not supposed to work. The probe will > >> be called on non- QCOM or non-Kryo QCOM platforms and I reckon it > >> will crash trying to execute something in qcom_smem_get. > > > > What do you mean by 'unconditionally'? > > Why should you even add/register a device "qcom-cpufreq-kryo" on other > platforms. Drivers can get registered, but only devices that are present or > required by the platform need to be registered. > > > The driver depends on the smem and nvmem drivers, which depend on > ARCH_QCOM: > > + depends on QCOM_QFPROM > > + depends on QCOM_SMEM > > > > Sure, but we have something called single image for all ARM64 platforms. > May be QCOM still used to tweeking config to build binary for your particular > mobile platform but the distro kernel need single binary to work on all > platforms. We have moved far away from platform specific builds long back > now IIRC. > > > And if SMEM read in the probe returns something other than Kryo, it will > exit. > > > > Check what this driver does ? > > msm_id = qcom_smem_get(QCOM_SMEM_HOST_ANY, > MSM_ID_SMEM, &len); > msm_id++; > switch ((enum _msm_id)*msm_id) > > I think it *will and should* crash here ? You need to check the return value > for sure. But since qcom_smem_get return -EPROBE_DEFER, we keep > retrying even on non QCOM platforms which is something I would like to > avoid. > > Therefore that's not the main concern. Why do I have to see "qcom-cpufreq- > kryo" device registered on my non QCOM platform ? > > -- > Regards, > Sudeep
On 24/05/18 15:10, ilialin@codeaurora.org wrote: > Thank you for the explanation. However, could you suggest, which > condition should I check then? Device tree? > Yes some compatible which is applicable for all the SoCs or platforms on which this driver can work ?
OK, got you. Is "operating-points-v2-kryo-cpu" good enough? > -----Original Message----- > From: Sudeep Holla <sudeep.holla@arm.com> > Sent: Thursday, May 24, 2018 17:48 > To: ilialin@codeaurora.org > Cc: Sudeep Holla <sudeep.holla@arm.com>; linux-pm@vger.kernel.org; > devicetree@vger.kernel.org; linux-kernel@vger.kernel.org; > vireshk@kernel.org; nm@ti.com; sboyd@kernel.org; robh@kernel.org; > mark.rutland@arm.com; rjw@rjwysocki.net > Subject: Re: [PATCH v12 1/2] cpufreq: Add Kryo CPU scaling driver > > > > On 24/05/18 15:10, ilialin@codeaurora.org wrote: > > Thank you for the explanation. However, could you suggest, which > > condition should I check then? Device tree? > > > > Yes some compatible which is applicable for all the SoCs or platforms on > which this driver can work ? > > -- > Regards, > Sudeep
On 24/05/18 15:52, ilialin@codeaurora.org wrote: > OK, got you. > Is "operating-points-v2-kryo-cpu" good enough? > Not sure if I can answer that as I don't have full knowledge on PM on all Kryo CPUs. Will this driver work on all those platforms which will have "operating-points-v2-kryo-cpu" ? If yes, then go ahead. I would prefer using some compatible in the CPU node rather that OPP, but that's just my opinion. Check with other QCOM guys on the list who have worked on CPUFreq or still working.(Taniya, Saravana, S Boyd, ...?)
diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm index de55c7d..0bfd40e 100644 --- a/drivers/cpufreq/Kconfig.arm +++ b/drivers/cpufreq/Kconfig.arm @@ -124,6 +124,16 @@ config ARM_OMAP2PLUS_CPUFREQ depends on ARCH_OMAP2PLUS default ARCH_OMAP2PLUS +config ARM_QCOM_CPUFREQ_KRYO + bool "Qualcomm Kryo based CPUFreq" + depends on QCOM_QFPROM + depends on QCOM_SMEM + select PM_OPP + help + This adds the CPUFreq driver for Qualcomm Kryo SoC based boards. + + If in doubt, say N. + config ARM_S3C_CPUFREQ bool help diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile index 8d24ade..fb4a2ec 100644 --- a/drivers/cpufreq/Makefile +++ b/drivers/cpufreq/Makefile @@ -65,6 +65,7 @@ obj-$(CONFIG_MACH_MVEBU_V7) += mvebu-cpufreq.o obj-$(CONFIG_ARM_OMAP2PLUS_CPUFREQ) += omap-cpufreq.o obj-$(CONFIG_ARM_PXA2xx_CPUFREQ) += pxa2xx-cpufreq.o obj-$(CONFIG_PXA3xx) += pxa3xx-cpufreq.o +obj-$(CONFIG_ARM_QCOM_CPUFREQ_KRYO) += qcom-cpufreq-kryo.o obj-$(CONFIG_ARM_S3C2410_CPUFREQ) += s3c2410-cpufreq.o obj-$(CONFIG_ARM_S3C2412_CPUFREQ) += s3c2412-cpufreq.o obj-$(CONFIG_ARM_S3C2416_CPUFREQ) += s3c2416-cpufreq.o diff --git a/drivers/cpufreq/cpufreq-dt-platdev.c b/drivers/cpufreq/cpufreq-dt-platdev.c index 3b585e4..77d6ab8 100644 --- a/drivers/cpufreq/cpufreq-dt-platdev.c +++ b/drivers/cpufreq/cpufreq-dt-platdev.c @@ -118,6 +118,9 @@ { .compatible = "nvidia,tegra124", }, + { .compatible = "qcom,apq8096", }, + { .compatible = "qcom,msm8996", }, + { .compatible = "st,stih407", }, { .compatible = "st,stih410", }, diff --git a/drivers/cpufreq/qcom-cpufreq-kryo.c b/drivers/cpufreq/qcom-cpufreq-kryo.c new file mode 100644 index 0000000..9fe379c --- /dev/null +++ b/drivers/cpufreq/qcom-cpufreq-kryo.c @@ -0,0 +1,194 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2018, The Linux Foundation. All rights reserved. + */ + +/* + * In Certain QCOM SoCs like apq8096 and msm8996 that have KRYO processors, + * the CPU frequency subset and voltage value of each OPP varies + * based on the silicon variant in use. Qualcomm Process Voltage Scaling Tables + * defines the voltage and frequency value based on the msm-id in SMEM + * and speedbin blown in the efuse combination. + * The qcom-cpufreq-kryo driver reads the msm-id and efuse value from the SoC + * to provide the OPP framework with required information. + * This is used to determine the voltage and frequency value for each OPP of + * operating-points-v2 table when it is parsed by the OPP framework. + */ + +#include <linux/cpu.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/nvmem-consumer.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pm_opp.h> +#include <linux/slab.h> +#include <linux/soc/qcom/smem.h> + +#define MSM_ID_SMEM 137 + +enum _msm_id { + MSM8996V3 = 0xF6ul, + APQ8096V3 = 0x123ul, + MSM8996SG = 0x131ul, + APQ8096SG = 0x138ul, +}; + +enum _msm8996_version { + MSM8996_V3, + MSM8996_SG, + NUM_OF_MSM8996_VERSIONS, +}; + +static enum _msm8996_version __init qcom_cpufreq_kryo_get_msm_id(void) +{ + size_t len; + u32 *msm_id; + enum _msm8996_version version; + + msm_id = qcom_smem_get(QCOM_SMEM_HOST_ANY, MSM_ID_SMEM, &len); + /* The first 4 bytes are format, next to them is the actual msm-id */ + msm_id++; + + switch ((enum _msm_id)*msm_id) { + case MSM8996V3: + case APQ8096V3: + version = MSM8996_V3; + break; + case MSM8996SG: + case APQ8096SG: + version = MSM8996_SG; + break; + default: + version = NUM_OF_MSM8996_VERSIONS; + } + + return version; +} + +static int qcom_cpufreq_kryo_probe(struct platform_device *pdev) +{ + struct opp_table *opp_tables[NR_CPUS] = {0}; + struct platform_device *cpufreq_dt_pdev; + enum _msm8996_version msm8996_version; + struct nvmem_cell *speedbin_nvmem; + struct device_node *np; + struct device *cpu_dev; + unsigned cpu; + u8 *speedbin; + u32 versions; + size_t len; + int ret; + + cpu_dev = get_cpu_device(0); + if (NULL == cpu_dev) + return -ENODEV; + + msm8996_version = qcom_cpufreq_kryo_get_msm_id(); + if (NUM_OF_MSM8996_VERSIONS == msm8996_version) { + dev_err(cpu_dev, "Not Snapdragon 820/821!"); + return -ENODEV; + } + + np = dev_pm_opp_of_get_opp_desc_node(cpu_dev); + if (IS_ERR(np)) + return PTR_ERR(np); + + if (!of_device_is_compatible(np, "operating-points-v2-kryo-cpu")) { + of_node_put(np); + return -ENOENT; + } + + speedbin_nvmem = of_nvmem_cell_get(np, NULL); + of_node_put(np); + if (IS_ERR(speedbin_nvmem)) { + dev_err(cpu_dev, "Could not get nvmem cell: %ld\n", + PTR_ERR(speedbin_nvmem)); + return PTR_ERR(speedbin_nvmem); + } + + speedbin = nvmem_cell_read(speedbin_nvmem, &len); + nvmem_cell_put(speedbin_nvmem); + + switch (msm8996_version) { + case MSM8996_V3: + versions = 1 << (unsigned int)(*speedbin); + break; + case MSM8996_SG: + versions = 1 << ((unsigned int)(*speedbin) + 4); + break; + default: + BUG(); + break; + } + + for_each_possible_cpu(cpu) { + cpu_dev = get_cpu_device(cpu); + if (NULL == cpu_dev) { + ret = -ENODEV; + goto free_opp; + } + + opp_tables[cpu] = dev_pm_opp_set_supported_hw(cpu_dev, + &versions, 1); + if (IS_ERR(opp_tables[cpu])) { + ret = PTR_ERR(opp_tables[cpu]); + dev_err(cpu_dev, "Failed to set supported hardware\n"); + goto free_opp; + } + } + + cpufreq_dt_pdev = platform_device_register_simple("cpufreq-dt", -1, + NULL, 0); + if (!IS_ERR(cpufreq_dt_pdev)) + return 0; + + ret = PTR_ERR(cpufreq_dt_pdev); + dev_err(cpu_dev, "Failed to register platform device\n"); + +free_opp: + for_each_possible_cpu(cpu) { + if (IS_ERR_OR_NULL(opp_tables[cpu])) + break; + dev_pm_opp_put_supported_hw(opp_tables[cpu]); + } + + return ret; +} + +static struct platform_driver qcom_cpufreq_kryo_driver = { + .probe = qcom_cpufreq_kryo_probe, + .driver = { + .name = "qcom-cpufreq-kryo", + }, +}; + +/* + * Since the driver depends on smem and nvmem drivers, which may + * return EPROBE_DEFER, all the real activity is done in the probe, + * which may be defered as well. The init here is only registering + * the driver and the platform device. + */ +static int __init qcom_cpufreq_kryo_init(void) +{ + int ret; + + ret = platform_driver_register(&qcom_cpufreq_kryo_driver); + if (unlikely(ret < 0)) + return ret; + + ret = PTR_ERR_OR_ZERO(platform_device_register_simple( + "qcom-cpufreq-kryo", -1, NULL, 0)); + if (unlikely(ret < 0)) { + platform_driver_unregister(&qcom_cpufreq_kryo_driver); + return ret; + } + + return 0; +} +module_init(qcom_cpufreq_kryo_init); + +MODULE_DESCRIPTION("Qualcomm Technologies, Inc. Kryo CPUfreq driver"); +MODULE_LICENSE("GPL v2");
In Certain QCOM SoCs like apq8096 and msm8996 that have KRYO processors, the CPU frequency subset and voltage value of each OPP varies based on the silicon variant in use. Qualcomm Process Voltage Scaling Tables defines the voltage and frequency value based on the msm-id in SMEM and speedbin blown in the efuse combination. The qcom-cpufreq-kryo driver reads the msm-id and efuse value from the SoC to provide the OPP framework with required information. This is used to determine the voltage and frequency value for each OPP of operating-points-v2 table when it is parsed by the OPP framework. Signed-off-by: Ilia Lin <ilialin@codeaurora.org> --- drivers/cpufreq/Kconfig.arm | 10 ++ drivers/cpufreq/Makefile | 1 + drivers/cpufreq/cpufreq-dt-platdev.c | 3 + drivers/cpufreq/qcom-cpufreq-kryo.c | 194 +++++++++++++++++++++++++++++++++++ 4 files changed, 208 insertions(+) create mode 100644 drivers/cpufreq/qcom-cpufreq-kryo.c