On Sat, 2021-04-17 at 11:00 +0200, Hans de Goede wrote: > Hi, > > On 4/17/21 5:12 AM, David E. Box wrote: > > From: Gayatri Kammela <gayatri.kammela@xxxxxxxxx> > > > > Platforms that support low power modes (LPM) such as Tiger Lake > > maintain > > requirements for each sub-state that a readable in the PMC. > > However, unlike > > LPM status registers, requirement registers are not memory mapped > > but are > > available from an ACPI _DSM. Collect the requirements for Tiger > > Lake using > > the _DSM method and store in a buffer. > > > > Signed-off-by: Gayatri Kammela <gayatri.kammela@xxxxxxxxx> > > Co-developed-by: David E. Box <david.e.box@xxxxxxxxxxxxxxx> > > Signed-off-by: David E. Box <david.e.box@xxxxxxxxxxxxxxx> > > Reviewed-by: Hans de Goede <hdegoede@xxxxxxxxxx> > > --- > > > > V2: - Move buffer allocation so that it does not need to be > > freed > > (which was missing anyway) when an error is encountered. > > - Use label to free out_obj after errors > > - Use memcpy instead of memcpy_fromio for ACPI memory > > > > drivers/platform/x86/intel_pmc_core.c | 56 > > +++++++++++++++++++++++++++ > > drivers/platform/x86/intel_pmc_core.h | 2 + > > 2 files changed, 58 insertions(+) > > > > diff --git a/drivers/platform/x86/intel_pmc_core.c > > b/drivers/platform/x86/intel_pmc_core.c > > index 0e59a84b51bf..97efe9a6bd01 100644 > > --- a/drivers/platform/x86/intel_pmc_core.c > > +++ b/drivers/platform/x86/intel_pmc_core.c > > @@ -23,7 +23,9 @@ > > #include <linux/slab.h> > > #include <linux/suspend.h> > > #include <linux/uaccess.h> > > +#include <linux/uuid.h> > > > > +#include <acpi/acpi_bus.h> > > #include <asm/cpu_device_id.h> > > #include <asm/intel-family.h> > > #include <asm/msr.h> > > @@ -31,6 +33,9 @@ > > > > #include "intel_pmc_core.h" > > > > +#define ACPI_S0IX_DSM_UUID "57a6512e-3979-4e9d-9708- > > ff13b2508972" > > +#define ACPI_GET_LOW_MODE_REGISTERS 1 > > + > > /* PKGC MSRs are common across Intel Core SoCs */ > > static const struct pmc_bit_map msr_map[] = { > > {"Package C2", MSR_PKG_C2_RESIDENCY}, > > @@ -590,6 +595,53 @@ static const struct pmc_reg_map tgl_reg_map = > > { > > .etr3_offset = ETR3_OFFSET, > > }; > > > > +static void pmc_core_get_tgl_lpm_reqs(struct platform_device > > *pdev) > > +{ > > + struct pmc_dev *pmcdev = platform_get_drvdata(pdev); > > + const int num_maps = pmcdev->map->lpm_num_maps; > > + size_t lpm_size = LPM_MAX_NUM_MODES * num_maps * 4; > > The type of lpm_size should be an u32, so that it matches > the type of out_obj->buffer.length. > > > + union acpi_object *out_obj; > > + struct acpi_device *adev; > > + guid_t s0ix_dsm_guid; > > + u32 *lpm_req_regs, *addr; > > + > > + adev = ACPI_COMPANION(&pdev->dev); > > + if (!adev) > > + return; > > + > > + guid_parse(ACPI_S0IX_DSM_UUID, &s0ix_dsm_guid); > > + > > + out_obj = acpi_evaluate_dsm(adev->handle, &s0ix_dsm_guid, > > 0, > > + ACPI_GET_LOW_MODE_REGISTERS, > > NULL); > > + if (out_obj && out_obj->type == ACPI_TYPE_BUFFER) { > > + int size = out_obj->buffer.length; > > out_obj->buffer.length is an u32, please make this an u32 too. > > > + > > + if (size != lpm_size) { > > + acpi_handle_debug(adev->handle, > > + "_DSM returned unexpected buffer > > size," > > + " have %d, expect %ld\n", size, > > lpm_size); > > And use %u here (twice), this should also fix the warnings reported > by the kernel test robot. > > If there are no objections against the suggested changes, then I can > fix this up while merging this. > > Please let me know if the suggested changes are ok with you. Changes are good with me. Thanks for the fixup. David > > Regards, > > Hans > > > > + goto free_acpi_obj; > > + } > > + } else { > > + acpi_handle_debug(adev->handle, > > + "_DSM function 0 evaluation > > failed\n"); > > + goto free_acpi_obj; > > + } > > + > > + addr = (u32 *)out_obj->buffer.pointer; > > + > > + lpm_req_regs = devm_kzalloc(&pdev->dev, lpm_size * > > sizeof(u32), > > + GFP_KERNEL); > > + if (!lpm_req_regs) > > + goto free_acpi_obj; > > + > > + memcpy(lpm_req_regs, addr, lpm_size); > > + pmcdev->lpm_req_regs = lpm_req_regs; > > + > > +free_acpi_obj: > > + ACPI_FREE(out_obj); > > +} > > + > > static inline u32 pmc_core_reg_read(struct pmc_dev *pmcdev, int > > reg_offset) > > { > > return readl(pmcdev->regbase + reg_offset); > > @@ -1424,10 +1476,14 @@ static int pmc_core_probe(struct > > platform_device *pdev) > > return -ENOMEM; > > > > mutex_init(&pmcdev->lock); > > + > > pmcdev->pmc_xram_read_bit = > > pmc_core_check_read_lock_bit(pmcdev); > > pmc_core_get_low_power_modes(pmcdev); > > pmc_core_do_dmi_quirks(pmcdev); > > > > + if (pmcdev->map == &tgl_reg_map) > > + pmc_core_get_tgl_lpm_reqs(pdev); > > + > > /* > > * On TGL, due to a hardware limitation, the GBE LTR blocks > > PC10 when > > * a cable is attached. Tell the PMC to ignore it. > > diff --git a/drivers/platform/x86/intel_pmc_core.h > > b/drivers/platform/x86/intel_pmc_core.h > > index aa44fd5399cc..64fb368f40f6 100644 > > --- a/drivers/platform/x86/intel_pmc_core.h > > +++ b/drivers/platform/x86/intel_pmc_core.h > > @@ -294,6 +294,7 @@ struct pmc_reg_map { > > * @s0ix_counter: S0ix residency (step adjusted) > > * @num_lpm_modes: Count of enabled modes > > * @lpm_en_modes: Array of enabled modes from lowest to > > highest priority > > + * @lpm_req_regs: List of substate requirements > > * > > * pmc_dev contains info about power management controller device. > > */ > > @@ -310,6 +311,7 @@ struct pmc_dev { > > u64 s0ix_counter; > > int num_lpm_modes; > > int lpm_en_modes[LPM_MAX_NUM_MODES]; > > + u32 *lpm_req_regs; > > }; > > > > #define pmc_for_each_mode(i, mode, pmcdev) \ > > >