[V3] platform/x86: intel_pmc_core: Add CNP SLPS0 debug registers

From: Box, David E
Date: Fri Jun 08 2018 - 20:02:49 EST


Adds debugfs access to registers in the Cannon Point PCH PMC that are
useful for debugging #SLP_S0 signal assertion and other low power relate
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.

Signed-off-by: Box, David E <david.e.box@xxxxxxxxx>
---
V3:
- use null terminator in bit_map array
- replaced ternary operator with if/else
- Removed space fixes on old code
V2:
- Clear latch bit after use
- Pass pmc_dev as parameter
- Use DEFINE_SHOW_ATTRIBUTE macro

drivers/platform/x86/intel_pmc_core.c | 120 ++++++++++++++++++++++++++++++++++
drivers/platform/x86/intel_pmc_core.h | 6 ++
2 files changed, 126 insertions(+)

diff --git a/drivers/platform/x86/intel_pmc_core.c b/drivers/platform/x86/intel_pmc_core.c
index 43bbe74743d9..2d272a3e0176 100644
--- a/drivers/platform/x86/intel_pmc_core.c
+++ b/drivers/platform/x86/intel_pmc_core.c
@@ -196,9 +196,67 @@ 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)},
+ {"MAIN_PLL_OFF", BIT(4)},
+ {"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 pmc_bit_map *cnp_slps0_dbg_maps[] = {
+ cnp_slps0_dbg0_map,
+ cnp_slps0_dbg1_map,
+ cnp_slps0_dbg2_map,
+ NULL,
+};
+
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,
.ltr_ignore_offset = CNP_PMC_LTR_IGNORE_OFFSET,
.regmap_length = CNP_PMC_MMIO_REG_LEN,
.ppfear0_offset = CNP_PMC_HOST_PPFEAR0A,
@@ -252,6 +310,8 @@ 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 +541,57 @@ 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);
+ if (reset)
+ fd &= ~CNP_PMC_LATCH_SLPS0_EVENTS;
+ else
+ 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->private;
+ const struct pmc_bit_map **maps = pmcdev->map->slps0_dbg_maps;
+ const struct pmc_bit_map *map;
+ int offset;
+ u32 data;
+
+ pmc_core_slps0_dbg_latch(pmcdev, false);
+ offset = pmcdev->map->slps0_dbg_offset;
+ while (*maps) {
+ map = *maps;
+ data = pmc_core_reg_read(pmcdev, offset);
+ offset += 4;
+ while (map->name) {
+ seq_printf(s, "SLP_S0_DBG: %-32s\tState: %s\n",
+ map->name,
+ data & map->bit_mask ?
+ "Yes" : "No");
+ ++map;
+ }
+ ++maps;
+ }
+ pmc_core_slps0_dbg_latch(pmcdev, true);
+ return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(pmc_core_slps0_dbg);
+
static void pmc_core_dbgfs_unregister(struct pmc_dev *pmcdev)
{
debugfs_remove_recursive(pmcdev->dbgfs_dir);
@@ -514,6 +625,15 @@ 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,
+ 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 5fa5f97870aa..93a7e99e1f8b 100644
--- a/drivers/platform/x86/intel_pmc_core.h
+++ b/drivers/platform/x86/intel_pmc_core.h
@@ -127,12 +127,14 @@ enum ppfear_regs {
#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_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;
@@ -145,6 +147,7 @@ struct pmc_bit_map {
* @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 +156,7 @@ 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*
*
* Each PCH has unique set of register offsets and bit indexes. This structure
* captures them to have a common implementation.
@@ -161,6 +165,7 @@ 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 pmc_bit_map **slps0_dbg_maps;
const u32 slp_s0_offset;
const u32 ltr_ignore_offset;
const int regmap_length;
@@ -168,6 +173,7 @@ struct pmc_reg_map {
const int ppfear_buckets;
const u32 pm_cfg_offset;
const int pm_read_disable_bit;
+ const u32 slps0_dbg_offset;
};

/**
--
2.14.4