[PATCH] platform/x86: intel_pmc_core: Make the driver PCH family agnostic

From: Srinivas Pandruvada
Date: Sat Aug 12 2017 - 12:52:55 EST


Although this driver did pretty good job in abstracting PCH specific
interfaces, but still there are some loose ends. For example
SLP_S0 counter (for reading SLP_S0 residency), PM config offset (for
checking permissions to read XRAM) and PPFEAR offset (for reading IP
status) is still hardcoded for a specific family of PCH.

This change extended the struct pmc_reg_map to allow per family
configuration of offsets and bits.

No functional change is expected with this change. This change allows
seamless additions to new PCH and create a baseline for other platform
specific extensions.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx>
---
drivers/platform/x86/intel_pmc_core.c | 31 +++++++++++++++++++++----------
drivers/platform/x86/intel_pmc_core.h | 30 +++++++++++++++++++++++++++++-
2 files changed, 50 insertions(+), 11 deletions(-)

diff --git a/drivers/platform/x86/intel_pmc_core.c b/drivers/platform/x86/intel_pmc_core.c
index 914bcd2..17e08b4 100644
--- a/drivers/platform/x86/intel_pmc_core.c
+++ b/drivers/platform/x86/intel_pmc_core.c
@@ -110,6 +110,13 @@ static const struct pmc_reg_map spt_reg_map = {
.pfear_sts = spt_pfear_map,
.mphy_sts = spt_mphy_map,
.pll_sts = spt_pll_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,
+ .ppfear0_offset = SPT_PMC_XRAM_PPFEAR0A,
+ .ppfear_buckets = SPT_PPFEAR_NUM_ENTRIES,
+ .pm_cfg_offset = SPT_PMC_PM_CFG_OFFSET,
+ .pm_read_disable_bit = SPT_PMC_READ_DISABLE_BIT,
};

static const struct pci_device_id pmc_pci_ids[] = {
@@ -157,12 +164,13 @@ static inline u32 pmc_core_adjust_slp_s0_step(u32 value)
int intel_pmc_slp_s0_counter_read(u32 *data)
{
struct pmc_dev *pmcdev = &pmc;
+ const struct pmc_reg_map *map = pmcdev->map;
u32 value;

if (!pmcdev->has_slp_s0_res)
return -EACCES;

- value = pmc_core_reg_read(pmcdev, SPT_PMC_SLP_S0_RES_COUNTER_OFFSET);
+ value = pmc_core_reg_read(pmcdev, map->slp_s0_offset);
*data = pmc_core_adjust_slp_s0_step(value);

return 0;
@@ -172,9 +180,10 @@ EXPORT_SYMBOL_GPL(intel_pmc_slp_s0_counter_read);
static int pmc_core_dev_state_get(void *data, u64 *val)
{
struct pmc_dev *pmcdev = data;
+ const struct pmc_reg_map *map = pmcdev->map;
u32 value;

- value = pmc_core_reg_read(pmcdev, SPT_PMC_SLP_S0_RES_COUNTER_OFFSET);
+ value = pmc_core_reg_read(pmcdev, map->slp_s0_offset);
*val = pmc_core_adjust_slp_s0_step(value);

return 0;
@@ -187,8 +196,8 @@ static int pmc_core_check_read_lock_bit(void)
struct pmc_dev *pmcdev = &pmc;
u32 value;

- value = pmc_core_reg_read(pmcdev, SPT_PMC_PM_CFG_OFFSET);
- return value & BIT(SPT_PMC_READ_DISABLE_BIT);
+ value = pmc_core_reg_read(pmcdev, pmcdev->map->pm_cfg_offset);
+ return value & BIT(pmcdev->map->pm_read_disable_bit);
}

#if IS_ENABLED(CONFIG_DEBUG_FS)
@@ -204,12 +213,13 @@ static int pmc_core_ppfear_sts_show(struct seq_file *s, void *unused)
{
struct pmc_dev *pmcdev = s->private;
const struct pmc_bit_map *map = pmcdev->map->pfear_sts;
- u8 pf_regs[NUM_ENTRIES];
+ u8 pf_regs[PPFEAR_MAX_NUM_ENTRIES];
int index, iter;

- iter = SPT_PMC_XRAM_PPFEAR0A;
+ iter = pmcdev->map->ppfear0_offset;

- for (index = 0; index < NUM_ENTRIES; index++, iter++)
+ for (index = 0; index < pmcdev->map->ppfear_buckets &&
+ index < PPFEAR_MAX_NUM_ENTRIES; index++, iter++)
pf_regs[index] = pmc_core_reg_read_byte(pmcdev, iter);

for (index = 0; map[index].name; index++)
@@ -376,6 +386,7 @@ static ssize_t pmc_core_ltr_ignore_write(struct file *file, const char __user
*userbuf, size_t count, loff_t *ppos)
{
struct pmc_dev *pmcdev = &pmc;
+ const struct pmc_reg_map *map = pmcdev->map;
u32 val, buf_size, fd;
int err = 0;

@@ -392,9 +403,9 @@ static ssize_t pmc_core_ltr_ignore_write(struct file *file, const char __user
goto out_unlock;
}

- fd = pmc_core_reg_read(pmcdev, SPT_PMC_LTR_IGNORE_OFFSET);
+ fd = pmc_core_reg_read(pmcdev, map->ltr_ignore_offset);
fd |= (1U << val);
- pmc_core_reg_write(pmcdev, SPT_PMC_LTR_IGNORE_OFFSET, fd);
+ pmc_core_reg_write(pmcdev, map->ltr_ignore_offset, fd);

out_unlock:
mutex_unlock(&pmcdev->lock);
@@ -530,8 +541,8 @@ static int pmc_core_probe(struct pci_dev *dev, const struct pci_device_id *id)
}

mutex_init(&pmcdev->lock);
- pmcdev->pmc_xram_read_bit = pmc_core_check_read_lock_bit();
pmcdev->map = map;
+ pmcdev->pmc_xram_read_bit = pmc_core_check_read_lock_bit();

err = pmc_core_dbgfs_register(pmcdev);
if (err < 0)
diff --git a/drivers/platform/x86/intel_pmc_core.h b/drivers/platform/x86/intel_pmc_core.h
index 5a48e77..3d225a9 100644
--- a/drivers/platform/x86/intel_pmc_core.h
+++ b/drivers/platform/x86/intel_pmc_core.h
@@ -38,7 +38,8 @@
#define SPT_PMC_SLP_S0_RES_COUNTER_STEP 0x64
#define PMC_BASE_ADDR_MASK ~(SPT_PMC_MMIO_REG_LEN - 1)
#define MTPMC_MASK 0xffff0000
-#define NUM_ENTRIES 5
+#define PPFEAR_MAX_NUM_ENTRIES 5
+#define SPT_PPFEAR_NUM_ENTRIES 5
#define SPT_PMC_READ_DISABLE_BIT 0x16
#define SPT_PMC_MSG_FULL_STS_BIT 0x18
#define NUM_RETRIES 100
@@ -126,10 +127,37 @@ struct pmc_bit_map {
u32 bit_mask;
};

+/**
+ * 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
+ * @slp_s0_offset: PWRMBASE offset to read SLP_S0 residency
+ * @ltr_ignore_offset: PWRMBASE offset to read/write LTR ignore bit
+ * @base_address: Base address of PWRMBASE defined in BIOS writer guide
+ * @regmap_length: Length of memory to map from PWRMBASE address to access
+ * @ppfear0_offset: PWRMBASE offset to to read PPFEAR*
+ * @ppfear_buckets: Number of 8 bits blocks to read all IP blocks from
+ * PPFEAR
+ * @pm_cfg_offset: PWRMBASE offset to PM_CFG register
+ * @pm_read_disable_bit: Bit index to read PMC_READ_DISABLE
+ *
+ * Each PCH has unique set of register offsets and bit indexes. This structure
+ * captures them to have a common implementation.
+ */
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 u32 slp_s0_offset;
+ const u32 ltr_ignore_offset;
+ const u32 base_address;
+ const int regmap_length;
+ const u32 ppfear0_offset;
+ const int ppfear_buckets;
+ const u32 pm_cfg_offset;
+ const int pm_read_disable_bit;
};

/**
--
2.7.4