On Thu, May 24, 2018 at 06:10:56PM -0700, David E. Box wrote: Thanks for sending this, Dave. Few comments below. > Adds debugfs access to registers in the Cannon Point PCH PMC that are Please use Cannonlake PCH. > useful for debugging #SLP_S0 signal assertion and other low power related assertion failures and other low power debug. > activities. Device pm states are latched in these registers whenever the > package enters C10 and can be read from slp_s0_debug_status. The pm > states may also be latched by writing 1 to slp_s0_dbg_latch which will > immediately capture the current state on the next read of > slp_s0_debug_status. Also while in intel_pmc_core.h clean up spacing. > Initially, unless the latch bit is not set the debugfs file does not show any information as expected but once you write Y to latch file, the debugfs file continues to show blockers even though you write N back there or unload - reload the driver. Please fix this. > Signed-off-by: David E. Box <david.e.box@xxxxxxxxxxxxxxx> > --- > > V2: > Per Andy Shevchenko: > - Clear latch bit after use > - Pass pmc_dev as parameter > - Use DEFINE_SHOW_ATTRIBUTE macro > > drivers/platform/x86/intel_pmc_core.c | 112 ++++++++++++++++++++++++++++++++++ > drivers/platform/x86/intel_pmc_core.h | 27 +++++--- > 2 files changed, 132 insertions(+), 7 deletions(-) > > diff --git a/drivers/platform/x86/intel_pmc_core.c b/drivers/platform/x86/intel_pmc_core.c > index 43bbe74..ed40999 100644 > --- a/drivers/platform/x86/intel_pmc_core.c > +++ b/drivers/platform/x86/intel_pmc_core.c > @@ -196,9 +196,64 @@ static const struct pmc_bit_map cnp_pfear_map[] = { > {} > }; > > +static const struct pmc_bit_map cnp_slps0_dbg0_map[] = { > + {"AUDIO_D3", BIT(0)}, > + {"OTG_D3", BIT(1)}, > + {"XHCI_D3", BIT(2)}, > + {"LPIO_D3", BIT(3)}, > + {"SDX_D3", BIT(4)}, > + {"SATA_D3", BIT(5)}, > + {"UFS0_D3", BIT(6)}, > + {"UFS1_D3", BIT(7)}, > + {"EMMC_D3", BIT(8)}, > +}; > + > +static const struct pmc_bit_map cnp_slps0_dbg1_map[] = { > + {"SDIO_PLL_OFF", BIT(0)}, > + {"USB2_PLL_OFF", BIT(1)}, > + {"AUDIO_PLL_OFF", BIT(2)}, > + {"OC_PLL_OFF", BIT(3)}, Please rename to ISCLK_OC as it is the preferred nomenclature for debug. > + {"MAIN_PLL_OFF", BIT(4)}, Ditto, please use ISCLK_MAIN. > + {"XOSC_OFF", BIT(5)}, > + {"LPC_CLKS_GATED", BIT(6)}, > + {"PCIE_CLKREQS_IDLE", BIT(7)}, > + {"AUDIO_ROSC_OFF", BIT(8)}, > + {"HPET_XOSC_CLK_REQ", BIT(9)}, > + {"PMC_ROSC_SLOW_CLK", BIT(10)}, > + {"AON2_ROSC_GATED", BIT(11)}, > + {"CLKACKS_DEASSERTED", BIT(12)}, > +}; > + > +static const struct pmc_bit_map cnp_slps0_dbg2_map[] = { > + {"MPHY_CORE_GATED", BIT(0)}, > + {"CSME_GATED", BIT(1)}, > + {"USB2_SUS_GATED", BIT(2)}, > + {"DYN_FLEX_IO_IDLE", BIT(3)}, > + {"GBE_NO_LINK", BIT(4)}, > + {"THERM_SEN_DISABLED", BIT(5)}, > + {"PCIE_LOW_POWER", BIT(6)}, > + {"ISH_VNNAON_REQ_ACT", BIT(7)}, > + {"ISH_VNN_REQ_ACT", BIT(8)}, > + {"CNV_VNNAON_REQ_ACT", BIT(9)}, > + {"CNV_VNN_REQ_ACT", BIT(10)}, > + {"NPK_VNNON_REQ_ACT", BIT(11)}, > + {"PMSYNC_STATE_IDLE", BIT(12)}, > + {"ALST_GT_THRES", BIT(13)}, > + {"PMC_ARC_PG_READY", BIT(14)}, > +}; > + > +static const struct slps0_dbg_map cnp_slps0_dbg_maps[] = { > + {cnp_slps0_dbg0_map, ARRAY_SIZE(cnp_slps0_dbg0_map)}, > + {cnp_slps0_dbg1_map, ARRAY_SIZE(cnp_slps0_dbg1_map)}, > + {cnp_slps0_dbg2_map, ARRAY_SIZE(cnp_slps0_dbg2_map)}, > +}; > + > static const struct pmc_reg_map cnp_reg_map = { > .pfear_sts = cnp_pfear_map, > .slp_s0_offset = CNP_PMC_SLP_S0_RES_COUNTER_OFFSET, > + .slps0_dbg_maps = cnp_slps0_dbg_maps, > + .slps0_dbg_offset = CNP_PMC_SLPS0_DBG_OFFSET, > + .slps0_dbg_num = ARRAY_SIZE(cnp_slps0_dbg_maps), > .ltr_ignore_offset = CNP_PMC_LTR_IGNORE_OFFSET, > .regmap_length = CNP_PMC_MMIO_REG_LEN, > .ppfear0_offset = CNP_PMC_HOST_PPFEAR0A, > @@ -252,6 +307,8 @@ static int pmc_core_check_read_lock_bit(void) > } > > #if IS_ENABLED(CONFIG_DEBUG_FS) > +static bool slps0_dbg_latch; > + > static void pmc_core_display_map(struct seq_file *s, int index, > u8 pf_reg, const struct pmc_bit_map *pf_map) > { > @@ -481,6 +538,52 @@ static const struct file_operations pmc_core_ltr_ignore_ops = { > .release = single_release, > }; > > +static void pmc_core_slps0_dbg_latch(struct pmc_dev *pmcdev, bool reset) > +{ > + const struct pmc_reg_map *map = pmcdev->map; > + u32 fd; > + > + mutex_lock(&pmcdev->lock); > + > + if (!reset && !slps0_dbg_latch) > + goto out_unlock; > + > + fd = pmc_core_reg_read(pmcdev, map->slps0_dbg_offset); > + reset ? (fd &= ~CNP_PMC_LATCH_SLPS0_EVENTS) : > + (fd |= CNP_PMC_LATCH_SLPS0_EVENTS); > + pmc_core_reg_write(pmcdev, map->slps0_dbg_offset, fd); > + > + slps0_dbg_latch = 0; > + > +out_unlock: > + mutex_unlock(&pmcdev->lock); > +} > + > +static int pmc_core_slps0_dbg_show(struct seq_file *s, void *unused) > +{ > + struct pmc_dev *pmcdev = s ? s->private : &pmc; > + const struct slps0_dbg_map *maps = pmcdev->map->slps0_dbg_maps; > + int num_slps0_dbg_regs = pmcdev->map->slps0_dbg_num; > + int i, offset; > + u32 data; > + > + pmc_core_slps0_dbg_latch(pmcdev, false); > + offset = pmcdev->map->slps0_dbg_offset; > + while (num_slps0_dbg_regs--) { > + data = pmc_core_reg_read(pmcdev, offset); > + offset += 4; > + for (i = 0; i < maps->size; i++) > + seq_printf(s, "SLP_S0_DBG: %-32s\tState: %s\n", > + maps->slps0_dbg_sts[i].name, > + data & maps->slps0_dbg_sts[i].bit_mask ? > + "Yes" : "No"); In current form, it looks pretty similar to pch_ip_power_gating_status output. Since it helps in debug, please use Blocks_slp_s0: instead of State: > + maps++; > + } > + pmc_core_slps0_dbg_latch(pmcdev, true); > + return 0; > +} > +DEFINE_SHOW_ATTRIBUTE(pmc_core_slps0_dbg); When the latch bit is not set, can we format the output of this attribute stating clearly whether the current blockers are "live" or the "last captured at PC10 entry" ? > + > static void pmc_core_dbgfs_unregister(struct pmc_dev *pmcdev) > { > debugfs_remove_recursive(pmcdev->dbgfs_dir); > @@ -514,6 +617,15 @@ static int pmc_core_dbgfs_register(struct pmc_dev *pmcdev) > 0444, dir, pmcdev, > &pmc_core_mphy_pg_ops); > > + if (pmcdev->map->slps0_dbg_maps) { > + debugfs_create_file("slp_s0_debug_status", 0444, slp_s0_dbg_latch > + dir, pmcdev, > + &pmc_core_slps0_dbg_fops); > + > + debugfs_create_bool("slp_s0_dbg_latch", 0644, > + dir, &slps0_dbg_latch); > + } > + > return 0; > } > #else > diff --git a/drivers/platform/x86/intel_pmc_core.h b/drivers/platform/x86/intel_pmc_core.h > index 5fa5f97..97e4b5a 100644 > --- a/drivers/platform/x86/intel_pmc_core.h > +++ b/drivers/platform/x86/intel_pmc_core.h > @@ -124,27 +124,35 @@ enum ppfear_regs { > #define SPT_PMC_BIT_MPHY_CMN_LANE3 BIT(3) > > /* Cannonlake Power Management Controller register offsets */ > -#define CNP_PMC_SLP_S0_RES_COUNTER_OFFSET 0x193C > -#define CNP_PMC_LTR_IGNORE_OFFSET 0x1B0C > -#define CNP_PMC_PM_CFG_OFFSET 0x1818 > +#define CNP_PMC_SLP_S0_RES_COUNTER_OFFSET 0x193C > +#define CNP_PMC_LTR_IGNORE_OFFSET 0x1B0C > +#define CNP_PMC_PM_CFG_OFFSET 0x1818 > +#define CNP_PMC_SLPS0_DBG_OFFSET 0x10B4 > /* Cannonlake: PGD PFET Enable Ack Status Register(s) start */ > -#define CNP_PMC_HOST_PPFEAR0A 0x1D90 > +#define CNP_PMC_HOST_PPFEAR0A 0x1D90 > > -#define CNP_PMC_MMIO_REG_LEN 0x2000 > -#define CNP_PPFEAR_NUM_ENTRIES 8 > -#define CNP_PMC_READ_DISABLE_BIT 22 > +#define CNP_PMC_MMIO_REG_LEN 0x2000 > +#define CNP_PPFEAR_NUM_ENTRIES 8 > +#define CNP_PMC_READ_DISABLE_BIT 22 > +#define CNP_PMC_LATCH_SLPS0_EVENTS BIT(31) > > struct pmc_bit_map { > const char *name; > u32 bit_mask; > }; > > +struct slps0_dbg_map { > + const struct pmc_bit_map *slps0_dbg_sts; > + int size; > +}; > + > /** > * struct pmc_reg_map - Structure used to define parameter unique to a > PCH family > * @pfear_sts: Maps name of IP block to PPFEAR* bit > * @mphy_sts: Maps name of MPHY lane to MPHY status lane status bit > * @pll_sts: Maps name of PLL to corresponding bit status > + * @slps0_dbg_maps: Array of SLP_S0_DBG* registers containing debug info > * @slp_s0_offset: PWRMBASE offset to read SLP_S0 residency > * @ltr_ignore_offset: PWRMBASE offset to read/write LTR ignore bit > * @regmap_length: Length of memory to map from PWRMBASE address to access > @@ -153,6 +161,8 @@ struct pmc_bit_map { > * PPFEAR > * @pm_cfg_offset: PWRMBASE offset to PM_CFG register > * @pm_read_disable_bit: Bit index to read PMC_READ_DISABLE > + * @slps0_dbg_offset: PWRMBASE offset to SLP_S0_DEBUG_REG* > + * @slps0_dbg_num: Number of SLP_S0_DEBUG_REG registers > * > * Each PCH has unique set of register offsets and bit indexes. This structure > * captures them to have a common implementation. > @@ -161,6 +171,7 @@ struct pmc_reg_map { > const struct pmc_bit_map *pfear_sts; > const struct pmc_bit_map *mphy_sts; > const struct pmc_bit_map *pll_sts; > + const struct slps0_dbg_map *slps0_dbg_maps; > const u32 slp_s0_offset; > const u32 ltr_ignore_offset; > const int regmap_length; > @@ -168,6 +179,8 @@ struct pmc_reg_map { > const int ppfear_buckets; > const u32 pm_cfg_offset; > const int pm_read_disable_bit; > + const u32 slps0_dbg_offset; > + const int slps0_dbg_num; > }; > > /** > -- > 2.7.4 > -- Best Regards, Rajneesh