ice: Add support for E825-C TS PLL handling

The CGU layout of E825-C is a little different than E822/E823. Add
support the new hardware adding relevant functions.

Signed-off-by: Michal Michalik <michal.michalik@intel.com>
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Reviewed-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Signed-off-by: Karol Kolacinski <karol.kolacinski@intel.com>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com>
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://lore.kernel.org/r/20240528-next-2024-05-28-ptp-refactors-v1-9-c082739bb6f6@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 246 insertions, 15 deletions

diff --git a/drivers/net/ethernet/intel/ice/ice_ptp_hw.c b/drivers/net/ethernet/intel/ice/ice_ptp_hw.c
index 691ea20811e7..2c41921f76e8 100644
--- a/drivers/net/ethernet/intel/ice/ice_ptp_hw.c
+++ b/drivers/net/ethernet/intel/ice/ice_ptp_hw.c
@@ -325,8 +325,8 @@ static const char *ice_clk_freq_str(enum ice_time_ref_freq clk_freq)
 static const char *ice_clk_src_str(enum ice_clk_src clk_src)
 {
 	switch (clk_src) {
-	case ICE_CLK_SRC_TCX0:
-		return "TCX0";
+	case ICE_CLK_SRC_TCXO:
+		return "TCXO";
 	case ICE_CLK_SRC_TIME_REF:
 		return "TIME_REF";
 	default:
@@ -338,7 +338,7 @@ static const char *ice_clk_src_str(enum ice_clk_src clk_src)
  * ice_cfg_cgu_pll_e82x - Configure the Clock Generation Unit
  * @hw: pointer to the HW struct
  * @clk_freq: Clock frequency to program
- * @clk_src: Clock source to select (TIME_REF, or TCX0)
+ * @clk_src: Clock source to select (TIME_REF, or TCXO)
  *
  * Configure the Clock Generation Unit with the desired clock frequency and
  * time reference, enabling the PLL which drives the PTP hardware clock.
@@ -372,10 +372,10 @@ static int ice_cfg_cgu_pll_e82x(struct ice_hw *hw,
 		return -EINVAL;
 	}
 
-	if (clk_src == ICE_CLK_SRC_TCX0 &&
+	if (clk_src == ICE_CLK_SRC_TCXO &&
 	    clk_freq != ICE_TIME_REF_FREQ_25_000) {
 		dev_warn(ice_hw_to_dev(hw),
-			 "TCX0 only supports 25 MHz frequency\n");
+			 "TCXO only supports 25 MHz frequency\n");
 		return -EINVAL;
 	}
 
@@ -480,16 +480,198 @@ static int ice_cfg_cgu_pll_e82x(struct ice_hw *hw,
 }
 
 /**
- * ice_init_cgu_e82x - Initialize CGU with settings from firmware
- * @hw: pointer to the HW structure
+ * ice_cfg_cgu_pll_e825c - Configure the Clock Generation Unit for E825-C
+ * @hw: pointer to the HW struct
+ * @clk_freq: Clock frequency to program
+ * @clk_src: Clock source to select (TIME_REF, or TCXO)
  *
- * Initialize the Clock Generation Unit of the E822 device.
+ * Configure the Clock Generation Unit with the desired clock frequency and
+ * time reference, enabling the PLL which drives the PTP hardware clock.
  *
- * Return: 0 on success, other error codes when failed to read/write/cfg CGU
+ * Return:
+ * * %0       - success
+ * * %-EINVAL - input parameters are incorrect
+ * * %-EBUSY  - failed to lock TS PLL
+ * * %other   - CGU read/write failure
  */
-static int ice_init_cgu_e82x(struct ice_hw *hw)
+static int ice_cfg_cgu_pll_e825c(struct ice_hw *hw,
+				 enum ice_time_ref_freq clk_freq,
+				 enum ice_clk_src clk_src)
+{
+	union tspll_ro_lock_e825c ro_lock;
+	union nac_cgu_dword16_e825c dw16;
+	union nac_cgu_dword23_e825c dw23;
+	union nac_cgu_dword19 dw19;
+	union nac_cgu_dword22 dw22;
+	union nac_cgu_dword24 dw24;
+	union nac_cgu_dword9 dw9;
+	int err;
+
+	if (clk_freq >= NUM_ICE_TIME_REF_FREQ) {
+		dev_warn(ice_hw_to_dev(hw), "Invalid TIME_REF frequency %u\n",
+			 clk_freq);
+		return -EINVAL;
+	}
+
+	if (clk_src >= NUM_ICE_CLK_SRC) {
+		dev_warn(ice_hw_to_dev(hw), "Invalid clock source %u\n",
+			 clk_src);
+		return -EINVAL;
+	}
+
+	if (clk_src == ICE_CLK_SRC_TCXO &&
+	    clk_freq != ICE_TIME_REF_FREQ_156_250) {
+		dev_warn(ice_hw_to_dev(hw),
+			 "TCXO only supports 156.25 MHz frequency\n");
+		return -EINVAL;
+	}
+
+	err = ice_read_cgu_reg_e82x(hw, NAC_CGU_DWORD9, &dw9.val);
+	if (err)
+		return err;
+
+	err = ice_read_cgu_reg_e82x(hw, NAC_CGU_DWORD24, &dw24.val);
+	if (err)
+		return err;
+
+	err = ice_read_cgu_reg_e82x(hw, NAC_CGU_DWORD16_E825C, &dw16.val);
+	if (err)
+		return err;
+
+	err = ice_read_cgu_reg_e82x(hw, NAC_CGU_DWORD23_E825C, &dw23.val);
+	if (err)
+		return err;
+
+	err = ice_read_cgu_reg_e82x(hw, TSPLL_RO_LOCK_E825C, &ro_lock.val);
+	if (err)
+		return err;
+
+	/* Log the current clock configuration */
+	ice_debug(hw, ICE_DBG_PTP, "Current CGU configuration -- %s, clk_src %s, clk_freq %s, PLL %s\n",
+		  dw24.ts_pll_enable ? "enabled" : "disabled",
+		  ice_clk_src_str(dw23.time_ref_sel),
+		  ice_clk_freq_str(dw9.time_ref_freq_sel),
+		  ro_lock.plllock_true_lock_cri ? "locked" : "unlocked");
+
+	/* Disable the PLL before changing the clock source or frequency */
+	if (dw23.ts_pll_enable) {
+		dw23.ts_pll_enable = 0;
+
+		err = ice_write_cgu_reg_e82x(hw, NAC_CGU_DWORD23_E825C,
+					     dw23.val);
+		if (err)
+			return err;
+	}
+
+	/* Set the frequency */
+	dw9.time_ref_freq_sel = clk_freq;
+
+	/* Enable the correct receiver */
+	if (clk_src == ICE_CLK_SRC_TCXO) {
+		dw9.time_ref_en = 0;
+		dw9.clk_eref0_en = 1;
+	} else {
+		dw9.time_ref_en = 1;
+		dw9.clk_eref0_en = 0;
+	}
+	err = ice_write_cgu_reg_e82x(hw, NAC_CGU_DWORD9, dw9.val);
+	if (err)
+		return err;
+
+	/* Choose the referenced frequency */
+	dw16.tspll_ck_refclkfreq =
+	e825c_cgu_params[clk_freq].tspll_ck_refclkfreq;
+	err = ice_write_cgu_reg_e82x(hw, NAC_CGU_DWORD16_E825C, dw16.val);
+	if (err)
+		return err;
+
+	/* Configure the TS PLL feedback divisor */
+	err = ice_read_cgu_reg_e82x(hw, NAC_CGU_DWORD19, &dw19.val);
+	if (err)
+		return err;
+
+	dw19.tspll_fbdiv_intgr =
+		e825c_cgu_params[clk_freq].tspll_fbdiv_intgr;
+	dw19.tspll_ndivratio =
+		e825c_cgu_params[clk_freq].tspll_ndivratio;
+
+	err = ice_write_cgu_reg_e82x(hw, NAC_CGU_DWORD19, dw19.val);
+	if (err)
+		return err;
+
+	/* Configure the TS PLL post divisor */
+	err = ice_read_cgu_reg_e82x(hw, NAC_CGU_DWORD22, &dw22.val);
+	if (err)
+		return err;
+
+	/* These two are constant for E825C */
+	dw22.time1588clk_div = 5;
+	dw22.time1588clk_sel_div2 = 0;
+
+	err = ice_write_cgu_reg_e82x(hw, NAC_CGU_DWORD22, dw22.val);
+	if (err)
+		return err;
+
+	/* Configure the TS PLL pre divisor and clock source */
+	err = ice_read_cgu_reg_e82x(hw, NAC_CGU_DWORD23_E825C, &dw23.val);
+	if (err)
+		return err;
+
+	dw23.ref1588_ck_div =
+		e825c_cgu_params[clk_freq].ref1588_ck_div;
+	dw23.time_ref_sel = clk_src;
+
+	err = ice_write_cgu_reg_e82x(hw, NAC_CGU_DWORD23_E825C, dw23.val);
+	if (err)
+		return err;
+
+	dw24.tspll_fbdiv_frac =
+		e825c_cgu_params[clk_freq].tspll_fbdiv_frac;
+
+	err = ice_write_cgu_reg_e82x(hw, NAC_CGU_DWORD24, dw24.val);
+	if (err)
+		return err;
+
+	/* Finally, enable the PLL */
+	dw23.ts_pll_enable = 1;
+
+	err = ice_write_cgu_reg_e82x(hw, NAC_CGU_DWORD23_E825C, dw23.val);
+	if (err)
+		return err;
+
+	/* Wait to verify if the PLL locks */
+	usleep_range(1000, 5000);
+
+	err = ice_read_cgu_reg_e82x(hw, TSPLL_RO_LOCK_E825C, &ro_lock.val);
+	if (err)
+		return err;
+
+	if (!ro_lock.plllock_true_lock_cri) {
+		dev_warn(ice_hw_to_dev(hw), "CGU PLL failed to lock\n");
+		return -EBUSY;
+	}
+
+	/* Log the current clock configuration */
+	ice_debug(hw, ICE_DBG_PTP, "New CGU configuration -- %s, clk_src %s, clk_freq %s, PLL %s\n",
+		  dw24.ts_pll_enable ? "enabled" : "disabled",
+		  ice_clk_src_str(dw23.time_ref_sel),
+		  ice_clk_freq_str(dw9.time_ref_freq_sel),
+		  ro_lock.plllock_true_lock_cri ? "locked" : "unlocked");
+
+	return 0;
+}
+
+/**
+ * ice_cfg_cgu_pll_dis_sticky_bits_e82x - disable TS PLL sticky bits
+ * @hw: pointer to the HW struct
+ *
+ * Configure the Clock Generation Unit TS PLL sticky bits so they don't latch on
+ * losing TS PLL lock, but always show current state.
+ *
+ * Return: 0 on success, other error codes when failed to read/write CGU
+ */
+static int ice_cfg_cgu_pll_dis_sticky_bits_e82x(struct ice_hw *hw)
 {
-	struct ice_ts_func_info *ts_info = &hw->func_caps.ts_func_info;
 	union tspll_cntr_bist_settings cntr_bist;
 	int err;
 
@@ -502,16 +684,65 @@ static int ice_init_cgu_e82x(struct ice_hw *hw)
 	cntr_bist.i_plllock_sel_0 = 0;
 	cntr_bist.i_plllock_sel_1 = 0;
 
-	err = ice_write_cgu_reg_e82x(hw, TSPLL_CNTR_BIST_SETTINGS,
-				     cntr_bist.val);
+	return ice_write_cgu_reg_e82x(hw, TSPLL_CNTR_BIST_SETTINGS,
+				      cntr_bist.val);
+}
+
+/**
+ * ice_cfg_cgu_pll_dis_sticky_bits_e825c - disable TS PLL sticky bits for E825-C
+ * @hw: pointer to the HW struct
+ *
+ * Configure the Clock Generation Unit TS PLL sticky bits so they don't latch on
+ * losing TS PLL lock, but always show current state.
+ *
+ * Return: 0 on success, other error codes when failed to read/write CGU
+ */
+static int ice_cfg_cgu_pll_dis_sticky_bits_e825c(struct ice_hw *hw)
+{
+	union tspll_bw_tdc_e825c bw_tdc;
+	int err;
+
+	err = ice_read_cgu_reg_e82x(hw, TSPLL_BW_TDC_E825C, &bw_tdc.val);
+	if (err)
+		return err;
+
+	bw_tdc.i_plllock_sel_1_0 = 0;
+
+	return ice_write_cgu_reg_e82x(hw, TSPLL_BW_TDC_E825C, bw_tdc.val);
+}
+
+/**
+ * ice_init_cgu_e82x - Initialize CGU with settings from firmware
+ * @hw: pointer to the HW structure
+ *
+ * Initialize the Clock Generation Unit of the E822 device.
+ *
+ * Return: 0 on success, other error codes when failed to read/write/cfg CGU
+ */
+static int ice_init_cgu_e82x(struct ice_hw *hw)
+{
+	struct ice_ts_func_info *ts_info = &hw->func_caps.ts_func_info;
+	int err;
+
+	/* Disable sticky lock detection so lock err reported is accurate */
+	if (ice_is_e825c(hw))
+		err = ice_cfg_cgu_pll_dis_sticky_bits_e825c(hw);
+	else
+		err = ice_cfg_cgu_pll_dis_sticky_bits_e82x(hw);
 	if (err)
 		return err;
 
 	/* Configure the CGU PLL using the parameters from the function
 	 * capabilities.
 	 */
-	return ice_cfg_cgu_pll_e82x(hw, ts_info->time_ref,
-				   (enum ice_clk_src)ts_info->clk_src);
+	if (ice_is_e825c(hw))
+		err = ice_cfg_cgu_pll_e825c(hw, ts_info->time_ref,
+					    (enum ice_clk_src)ts_info->clk_src);
+	else
+		err = ice_cfg_cgu_pll_e82x(hw, ts_info->time_ref,
+					   (enum ice_clk_src)ts_info->clk_src);
+
+	return err;
 }
 
 /**