On Fri, Feb 01, 2019 at 01:02:33PM +0530, Rajneesh Bhardwaj wrote: > This patch introduces a new debugfs entry to read current Package > cstate residency counters. A similar variant of this patch was discussed > earlier "https://patchwork.kernel.org/patch/9908563/"; but didn't make it > into mainline for various reasons. Current version only adds debugfs > entry which is quite useful for S0ix debug but excludes the exported API > that was there in initial version. Though there are tools like turbostat > and socwatch which can also show this info but sometimes its more > practical to have it here as it's hard to switch between various tools for > S0ix debug when pmc_core driver is the primary debug tool. Internal and > external customers have requested for this patch to be included in the > PMC driver on many occasions and Google Chrome OS team has already included > it in their builds. This becomes handy when requesting logs from external > customers who may not always have above mentioned tools in their integrated > kernel builds. > > Package cstate residency MSRs provide useful debug information about > system idle states. In idle states system must enter deeper Package > cstates. Package cstates depend not only on Core cstates but also on > various IP block's power gating status and LTR values. > > For Intel Core SoCs Package C10 entry is a must for deeper sleep states > such as S0ix. "Suspend-to-idle" should ideally take this path: > PC0 -> PC10 -> S0ix. For S0ix debug, its logical to check for > Package C10 residency first if for some reason system fails to enter S0ix. > > Please refer to this link for MSR details: > https://software.intel.com/sites/default/files/managed/22/0d/335592-sdm-vol-4.pdf > > Usage: > cat /sys/kernel/debug/pmc_core/package_cstate_show > Package C2 : 0xec2e21735f > Package C3 : 0xc30113ba4 > Package C6 : 0x9ef4be15c5 > Package C7 : 0x1e011904 > Package C8 : 0x3c5653cfe5a > Package C9 : 0x0 > Package C10 : 0x16fff4289 > > Cc: Arjan van de Ven <ar...@linux.intel.com> > Cc: "David E. Box" <david.e....@intel.com> > Cc: Srinivas Pandruvada <srinivas.pandruv...@linux.intel.com> > Cc: Anshuman Gupta <anshuman.gu...@intel.com> > Cc: Len Brown <len.br...@intel.com> > Cc: Rafael J. Wysocki <rafael.j.wyso...@intel.com> > Signed-off-by: Rajneesh Bhardwaj <rajneesh.bhard...@linux.intel.com> Tested-by: Anshuman Gupta <anshuman.gu...@intel.com> Acked-by: Anshuman Gupta <anshuman.gu...@intel.com> > --- > drivers/platform/x86/intel_pmc_core.c | 38 +++++++++++++++++++++++++++ > drivers/platform/x86/intel_pmc_core.h | 1 + > 2 files changed, 39 insertions(+) > > diff --git a/drivers/platform/x86/intel_pmc_core.c > b/drivers/platform/x86/intel_pmc_core.c > index 400946b7a3b5..4e7aa1711148 100644 > --- a/drivers/platform/x86/intel_pmc_core.c > +++ b/drivers/platform/x86/intel_pmc_core.c > @@ -22,11 +22,24 @@ > > #include <asm/cpu_device_id.h> > #include <asm/intel-family.h> > +#include <asm/msr.h> > > #include "intel_pmc_core.h" > > static struct pmc_dev pmc; > > +/* PKGC MSRs are common across Intel Core SoCs */ > +static const struct pmc_bit_map msr_map[] = { > + {"Package C2", MSR_PKG_C2_RESIDENCY}, > + {"Package C3", MSR_PKG_C3_RESIDENCY}, > + {"Package C6", MSR_PKG_C6_RESIDENCY}, > + {"Package C7", MSR_PKG_C7_RESIDENCY}, > + {"Package C8", MSR_PKG_C8_RESIDENCY}, > + {"Package C9", MSR_PKG_C9_RESIDENCY}, > + {"Package C10", MSR_PKG_C10_RESIDENCY}, > + {} > +}; > + > static const struct pmc_bit_map spt_pll_map[] = { > {"MIPI PLL", SPT_PMC_BIT_MPHY_CMN_LANE0}, > {"GEN2 USB2PCIE2 PLL", SPT_PMC_BIT_MPHY_CMN_LANE1}, > @@ -129,6 +142,7 @@ static const struct pmc_reg_map spt_reg_map = { > .mphy_sts = spt_mphy_map, > .pll_sts = spt_pll_map, > .ltr_show_sts = spt_ltr_show_map, > + .msr_sts = msr_map, > .slp_s0_offset = SPT_PMC_SLP_S0_RES_COUNTER_OFFSET, > .ltr_ignore_offset = SPT_PMC_LTR_IGNORE_OFFSET, > .regmap_length = SPT_PMC_MMIO_REG_LEN, > @@ -318,6 +332,7 @@ static const struct pmc_reg_map cnp_reg_map = { > .slp_s0_offset = CNP_PMC_SLP_S0_RES_COUNTER_OFFSET, > .slps0_dbg_maps = cnp_slps0_dbg_maps, > .ltr_show_sts = cnp_ltr_show_map, > + .msr_sts = msr_map, > .slps0_dbg_offset = CNP_PMC_SLPS0_DBG_OFFSET, > .ltr_ignore_offset = CNP_PMC_LTR_IGNORE_OFFSET, > .regmap_length = CNP_PMC_MMIO_REG_LEN, > @@ -333,6 +348,7 @@ static const struct pmc_reg_map icl_reg_map = { > .slp_s0_offset = CNP_PMC_SLP_S0_RES_COUNTER_OFFSET, > .slps0_dbg_maps = cnp_slps0_dbg_maps, > .ltr_show_sts = cnp_ltr_show_map, > + .msr_sts = msr_map, > .slps0_dbg_offset = CNP_PMC_SLPS0_DBG_OFFSET, > .ltr_ignore_offset = CNP_PMC_LTR_IGNORE_OFFSET, > .regmap_length = CNP_PMC_MMIO_REG_LEN, > @@ -709,6 +725,25 @@ static int pmc_core_ltr_show(struct seq_file *s, void > *unused) > } > DEFINE_SHOW_ATTRIBUTE(pmc_core_ltr); > > +static int pmc_core_pkgc_show(struct seq_file *s, void *unused) > +{ > + struct pmc_dev *pmcdev = s->private; > + const struct pmc_bit_map *map = pmcdev->map->msr_sts; > + u64 pcstate_count; > + int index; > + > + for (index = 0; map[index].name ; index++) { > + if (rdmsrl_safe(map[index].bit_mask, &pcstate_count)) > + continue; > + > + seq_printf(s, "%-8s : 0x%llx\n", map[index].name, > + pcstate_count); > + } > + > + return 0; > +} > +DEFINE_SHOW_ATTRIBUTE(pmc_core_pkgc); > + > static void pmc_core_dbgfs_unregister(struct pmc_dev *pmcdev) > { > debugfs_remove_recursive(pmcdev->dbgfs_dir); > @@ -735,6 +770,9 @@ static int pmc_core_dbgfs_register(struct pmc_dev *pmcdev) > > debugfs_create_file("ltr_show", 0444, dir, pmcdev, &pmc_core_ltr_fops); > > + debugfs_create_file("package_cstate_show", 0444, dir, pmcdev, > + &pmc_core_pkgc_fops); > + > if (pmcdev->map->pll_sts) > debugfs_create_file("pll_status", 0444, dir, pmcdev, > &pmc_core_pll_fops); > diff --git a/drivers/platform/x86/intel_pmc_core.h > b/drivers/platform/x86/intel_pmc_core.h > index 78dd4229489d..6f1b64808075 100644 > --- a/drivers/platform/x86/intel_pmc_core.h > +++ b/drivers/platform/x86/intel_pmc_core.h > @@ -214,6 +214,7 @@ struct pmc_reg_map { > const struct pmc_bit_map *pll_sts; > const struct pmc_bit_map **slps0_dbg_maps; > const struct pmc_bit_map *ltr_show_sts; > + const struct pmc_bit_map *msr_sts; > const u32 slp_s0_offset; > const u32 ltr_ignore_offset; > const int regmap_length; > -- > 2.17.1 >
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