ice: ensure the hardware Clock Generation Unit is configured
authorJacob Keller <jacob.e.keller@intel.com>
Wed, 13 Oct 2021 15:55:58 +0000 (08:55 -0700)
committerTony Nguyen <anthony.l.nguyen@intel.com>
Tue, 21 Dec 2021 17:11:40 +0000 (09:11 -0800)
The E822 device has a Clock Generation Unit (CGU) responsible for
determining the clock frequency that drives the timers.

Ensure this function is initialized when bringing up the PTP support, so
that the clock has a known frequency.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Gurucharan G <gurucharanx.g@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
drivers/net/ethernet/intel/ice/ice_cgu_regs.h [new file with mode: 0644]
drivers/net/ethernet/intel/ice/ice_ptp_consts.h
drivers/net/ethernet/intel/ice/ice_ptp_hw.c
drivers/net/ethernet/intel/ice/ice_ptp_hw.h

diff --git a/drivers/net/ethernet/intel/ice/ice_cgu_regs.h b/drivers/net/ethernet/intel/ice/ice_cgu_regs.h
new file mode 100644 (file)
index 0000000..57abd52
--- /dev/null
@@ -0,0 +1,116 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (C) 2018-2021, Intel Corporation. */
+
+#ifndef _ICE_CGU_REGS_H_
+#define _ICE_CGU_REGS_H_
+
+#define NAC_CGU_DWORD9 0x24
+union nac_cgu_dword9 {
+       struct {
+               u32 time_ref_freq_sel : 3;
+               u32 clk_eref1_en : 1;
+               u32 clk_eref0_en : 1;
+               u32 time_ref_en : 1;
+               u32 time_sync_en : 1;
+               u32 one_pps_out_en : 1;
+               u32 clk_ref_synce_en : 1;
+               u32 clk_synce1_en : 1;
+               u32 clk_synce0_en : 1;
+               u32 net_clk_ref1_en : 1;
+               u32 net_clk_ref0_en : 1;
+               u32 clk_synce1_amp : 2;
+               u32 misc6 : 1;
+               u32 clk_synce0_amp : 2;
+               u32 one_pps_out_amp : 2;
+               u32 misc24 : 12;
+       } field;
+       u32 val;
+};
+
+#define NAC_CGU_DWORD19 0x4c
+union nac_cgu_dword19 {
+       struct {
+               u32 tspll_fbdiv_intgr : 8;
+               u32 fdpll_ulck_thr : 5;
+               u32 misc15 : 3;
+               u32 tspll_ndivratio : 4;
+               u32 tspll_iref_ndivratio : 3;
+               u32 misc19 : 1;
+               u32 japll_ndivratio : 4;
+               u32 japll_iref_ndivratio : 3;
+               u32 misc27 : 1;
+       } field;
+       u32 val;
+};
+
+#define NAC_CGU_DWORD22 0x58
+union nac_cgu_dword22 {
+       struct {
+               u32 fdpll_frac_div_out_nc : 2;
+               u32 fdpll_lock_int_for : 1;
+               u32 synce_hdov_int_for : 1;
+               u32 synce_lock_int_for : 1;
+               u32 fdpll_phlead_slip_nc : 1;
+               u32 fdpll_acc1_ovfl_nc : 1;
+               u32 fdpll_acc2_ovfl_nc : 1;
+               u32 synce_status_nc : 6;
+               u32 fdpll_acc1f_ovfl : 1;
+               u32 misc18 : 1;
+               u32 fdpllclk_div : 4;
+               u32 time1588clk_div : 4;
+               u32 synceclk_div : 4;
+               u32 synceclk_sel_div2 : 1;
+               u32 fdpllclk_sel_div2 : 1;
+               u32 time1588clk_sel_div2 : 1;
+               u32 misc3 : 1;
+       } field;
+       u32 val;
+};
+
+#define NAC_CGU_DWORD24 0x60
+union nac_cgu_dword24 {
+       struct {
+               u32 tspll_fbdiv_frac : 22;
+               u32 misc20 : 2;
+               u32 ts_pll_enable : 1;
+               u32 time_sync_tspll_align_sel : 1;
+               u32 ext_synce_sel : 1;
+               u32 ref1588_ck_div : 4;
+               u32 time_ref_sel : 1;
+       } field;
+       u32 val;
+};
+
+#define TSPLL_CNTR_BIST_SETTINGS 0x344
+union tspll_cntr_bist_settings {
+       struct {
+               u32 i_irefgen_settling_time_cntr_7_0 : 8;
+               u32 i_irefgen_settling_time_ro_standby_1_0 : 2;
+               u32 reserved195 : 5;
+               u32 i_plllock_sel_0 : 1;
+               u32 i_plllock_sel_1 : 1;
+               u32 i_plllock_cnt_6_0 : 7;
+               u32 i_plllock_cnt_10_7 : 4;
+               u32 reserved200 : 4;
+       } field;
+       u32 val;
+};
+
+#define TSPLL_RO_BWM_LF 0x370
+union tspll_ro_bwm_lf {
+       struct {
+               u32 bw_freqov_high_cri_7_0 : 8;
+               u32 bw_freqov_high_cri_9_8 : 2;
+               u32 biascaldone_cri : 1;
+               u32 plllock_gain_tran_cri : 1;
+               u32 plllock_true_lock_cri : 1;
+               u32 pllunlock_flag_cri : 1;
+               u32 afcerr_cri : 1;
+               u32 afcdone_cri : 1;
+               u32 feedfwrdgain_cal_cri_7_0 : 8;
+               u32 m2fbdivmod_cri_7_0 : 8;
+       } field;
+       u32 val;
+};
+
+#endif /* _ICE_CGU_REGS_H_ */
index 90e1e99..4109aa3 100644 (file)
@@ -81,6 +81,80 @@ const struct ice_time_ref_info_e822 e822_time_ref[NUM_ICE_TIME_REF_FREQ] = {
        },
 };
 
+const struct ice_cgu_pll_params_e822 e822_cgu_params[NUM_ICE_TIME_REF_FREQ] = {
+       /* ICE_TIME_REF_FREQ_25_000 -> 25 MHz */
+       {
+               /* refclk_pre_div */
+               1,
+               /* feedback_div */
+               197,
+               /* frac_n_div */
+               2621440,
+               /* post_pll_div */
+               6,
+       },
+
+       /* ICE_TIME_REF_FREQ_122_880 -> 122.88 MHz */
+       {
+               /* refclk_pre_div */
+               5,
+               /* feedback_div */
+               223,
+               /* frac_n_div */
+               524288,
+               /* post_pll_div */
+               7,
+       },
+
+       /* ICE_TIME_REF_FREQ_125_000 -> 125 MHz */
+       {
+               /* refclk_pre_div */
+               5,
+               /* feedback_div */
+               223,
+               /* frac_n_div */
+               524288,
+               /* post_pll_div */
+               7,
+       },
+
+       /* ICE_TIME_REF_FREQ_153_600 -> 153.6 MHz */
+       {
+               /* refclk_pre_div */
+               5,
+               /* feedback_div */
+               159,
+               /* frac_n_div */
+               1572864,
+               /* post_pll_div */
+               6,
+       },
+
+       /* ICE_TIME_REF_FREQ_156_250 -> 156.25 MHz */
+       {
+               /* refclk_pre_div */
+               5,
+               /* feedback_div */
+               159,
+               /* frac_n_div */
+               1572864,
+               /* post_pll_div */
+               6,
+       },
+
+       /* ICE_TIME_REF_FREQ_245_760 -> 245.76 MHz */
+       {
+               /* refclk_pre_div */
+               10,
+               /* feedback_div */
+               223,
+               /* frac_n_div */
+               524288,
+               /* post_pll_div */
+               7,
+       },
+};
+
 /* struct ice_vernier_info_e822
  *
  * E822 hardware calibrates the delay of the timestamp indication from the
index 87fd120..20204bb 100644 (file)
@@ -4,6 +4,7 @@
 #include "ice_common.h"
 #include "ice_ptp_hw.h"
 #include "ice_ptp_consts.h"
+#include "ice_cgu_regs.h"
 
 /* Low level functions for interacting with and managing the device clock used
  * for the Precision Time Protocol.
@@ -654,6 +655,289 @@ ice_clear_phy_tstamp_e822(struct ice_hw *hw, u8 quad, u8 idx)
 }
 
 /**
+ * ice_read_cgu_reg_e822 - Read a CGU register
+ * @hw: pointer to the HW struct
+ * @addr: Register address to read
+ * @val: storage for register value read
+ *
+ * Read the contents of a register of the Clock Generation Unit. Only
+ * applicable to E822 devices.
+ */
+static int
+ice_read_cgu_reg_e822(struct ice_hw *hw, u32 addr, u32 *val)
+{
+       struct ice_sbq_msg_input cgu_msg;
+       int err;
+
+       cgu_msg.opcode = ice_sbq_msg_rd;
+       cgu_msg.dest_dev = cgu;
+       cgu_msg.msg_addr_low = addr;
+       cgu_msg.msg_addr_high = 0x0;
+
+       err = ice_sbq_rw_reg(hw, &cgu_msg);
+       if (err) {
+               ice_debug(hw, ICE_DBG_PTP, "Failed to read CGU register 0x%04x, err %d\n",
+                         addr, err);
+               return err;
+       }
+
+       *val = cgu_msg.data;
+
+       return err;
+}
+
+/**
+ * ice_write_cgu_reg_e822 - Write a CGU register
+ * @hw: pointer to the HW struct
+ * @addr: Register address to write
+ * @val: value to write into the register
+ *
+ * Write the specified value to a register of the Clock Generation Unit. Only
+ * applicable to E822 devices.
+ */
+static int
+ice_write_cgu_reg_e822(struct ice_hw *hw, u32 addr, u32 val)
+{
+       struct ice_sbq_msg_input cgu_msg;
+       int err;
+
+       cgu_msg.opcode = ice_sbq_msg_wr;
+       cgu_msg.dest_dev = cgu;
+       cgu_msg.msg_addr_low = addr;
+       cgu_msg.msg_addr_high = 0x0;
+       cgu_msg.data = val;
+
+       err = ice_sbq_rw_reg(hw, &cgu_msg);
+       if (err) {
+               ice_debug(hw, ICE_DBG_PTP, "Failed to write CGU register 0x%04x, err %d\n",
+                         addr, err);
+               return err;
+       }
+
+       return err;
+}
+
+/**
+ * ice_clk_freq_str - Convert time_ref_freq to string
+ * @clk_freq: Clock frequency
+ *
+ * Convert the specified TIME_REF clock frequency to a string.
+ */
+static const char *ice_clk_freq_str(u8 clk_freq)
+{
+       switch ((enum ice_time_ref_freq)clk_freq) {
+       case ICE_TIME_REF_FREQ_25_000:
+               return "25 MHz";
+       case ICE_TIME_REF_FREQ_122_880:
+               return "122.88 MHz";
+       case ICE_TIME_REF_FREQ_125_000:
+               return "125 MHz";
+       case ICE_TIME_REF_FREQ_153_600:
+               return "153.6 MHz";
+       case ICE_TIME_REF_FREQ_156_250:
+               return "156.25 MHz";
+       case ICE_TIME_REF_FREQ_245_760:
+               return "245.76 MHz";
+       default:
+               return "Unknown";
+       }
+}
+
+/**
+ * ice_clk_src_str - Convert time_ref_src to string
+ * @clk_src: Clock source
+ *
+ * Convert the specified clock source to its string name.
+ */
+static const char *ice_clk_src_str(u8 clk_src)
+{
+       switch ((enum ice_clk_src)clk_src) {
+       case ICE_CLK_SRC_TCX0:
+               return "TCX0";
+       case ICE_CLK_SRC_TIME_REF:
+               return "TIME_REF";
+       default:
+               return "Unknown";
+       }
+}
+
+/**
+ * ice_cfg_cgu_pll_e822 - 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)
+ *
+ * Configure the Clock Generation Unit with the desired clock frequency and
+ * time reference, enabling the PLL which drives the PTP hardware clock.
+ */
+static int
+ice_cfg_cgu_pll_e822(struct ice_hw *hw, enum ice_time_ref_freq clk_freq,
+                    enum ice_clk_src clk_src)
+{
+       union tspll_ro_bwm_lf bwm_lf;
+       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_TCX0 &&
+           clk_freq != ICE_TIME_REF_FREQ_25_000) {
+               dev_warn(ice_hw_to_dev(hw),
+                        "TCX0 only supports 25 MHz frequency\n");
+               return -EINVAL;
+       }
+
+       err = ice_read_cgu_reg_e822(hw, NAC_CGU_DWORD9, &dw9.val);
+       if (err)
+               return err;
+
+       err = ice_read_cgu_reg_e822(hw, NAC_CGU_DWORD24, &dw24.val);
+       if (err)
+               return err;
+
+       err = ice_read_cgu_reg_e822(hw, TSPLL_RO_BWM_LF, &bwm_lf.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.field.ts_pll_enable ? "enabled" : "disabled",
+                 ice_clk_src_str(dw24.field.time_ref_sel),
+                 ice_clk_freq_str(dw9.field.time_ref_freq_sel),
+                 bwm_lf.field.plllock_true_lock_cri ? "locked" : "unlocked");
+
+       /* Disable the PLL before changing the clock source or frequency */
+       if (dw24.field.ts_pll_enable) {
+               dw24.field.ts_pll_enable = 0;
+
+               err = ice_write_cgu_reg_e822(hw, NAC_CGU_DWORD24, dw24.val);
+               if (err)
+                       return err;
+       }
+
+       /* Set the frequency */
+       dw9.field.time_ref_freq_sel = clk_freq;
+       err = ice_write_cgu_reg_e822(hw, NAC_CGU_DWORD9, dw9.val);
+       if (err)
+               return err;
+
+       /* Configure the TS PLL feedback divisor */
+       err = ice_read_cgu_reg_e822(hw, NAC_CGU_DWORD19, &dw19.val);
+       if (err)
+               return err;
+
+       dw19.field.tspll_fbdiv_intgr = e822_cgu_params[clk_freq].feedback_div;
+       dw19.field.tspll_ndivratio = 1;
+
+       err = ice_write_cgu_reg_e822(hw, NAC_CGU_DWORD19, dw19.val);
+       if (err)
+               return err;
+
+       /* Configure the TS PLL post divisor */
+       err = ice_read_cgu_reg_e822(hw, NAC_CGU_DWORD22, &dw22.val);
+       if (err)
+               return err;
+
+       dw22.field.time1588clk_div = e822_cgu_params[clk_freq].post_pll_div;
+       dw22.field.time1588clk_sel_div2 = 0;
+
+       err = ice_write_cgu_reg_e822(hw, NAC_CGU_DWORD22, dw22.val);
+       if (err)
+               return err;
+
+       /* Configure the TS PLL pre divisor and clock source */
+       err = ice_read_cgu_reg_e822(hw, NAC_CGU_DWORD24, &dw24.val);
+       if (err)
+               return err;
+
+       dw24.field.ref1588_ck_div = e822_cgu_params[clk_freq].refclk_pre_div;
+       dw24.field.tspll_fbdiv_frac = e822_cgu_params[clk_freq].frac_n_div;
+       dw24.field.time_ref_sel = clk_src;
+
+       err = ice_write_cgu_reg_e822(hw, NAC_CGU_DWORD24, dw24.val);
+       if (err)
+               return err;
+
+       /* Finally, enable the PLL */
+       dw24.field.ts_pll_enable = 1;
+
+       err = ice_write_cgu_reg_e822(hw, NAC_CGU_DWORD24, dw24.val);
+       if (err)
+               return err;
+
+       /* Wait to verify if the PLL locks */
+       usleep_range(1000, 5000);
+
+       err = ice_read_cgu_reg_e822(hw, TSPLL_RO_BWM_LF, &bwm_lf.val);
+       if (err)
+               return err;
+
+       if (!bwm_lf.field.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.field.ts_pll_enable ? "enabled" : "disabled",
+                 ice_clk_src_str(dw24.field.time_ref_sel),
+                 ice_clk_freq_str(dw9.field.time_ref_freq_sel),
+                 bwm_lf.field.plllock_true_lock_cri ? "locked" : "unlocked");
+
+       return 0;
+}
+
+/**
+ * ice_init_cgu_e822 - Initialize CGU with settings from firmware
+ * @hw: pointer to the HW structure
+ *
+ * Initialize the Clock Generation Unit of the E822 device.
+ */
+static int ice_init_cgu_e822(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;
+
+       err = ice_read_cgu_reg_e822(hw, TSPLL_CNTR_BIST_SETTINGS,
+                                   &cntr_bist.val);
+       if (err)
+               return err;
+
+       /* Disable sticky lock detection so lock err reported is accurate */
+       cntr_bist.field.i_plllock_sel_0 = 0;
+       cntr_bist.field.i_plllock_sel_1 = 0;
+
+       err = ice_write_cgu_reg_e822(hw, TSPLL_CNTR_BIST_SETTINGS,
+                                    cntr_bist.val);
+       if (err)
+               return err;
+
+       /* Configure the CGU PLL using the parameters from the function
+        * capabilities.
+        */
+       err = ice_cfg_cgu_pll_e822(hw, ts_info->time_ref,
+                                  (enum ice_clk_src)ts_info->clk_src);
+       if (err)
+               return err;
+
+       return 0;
+}
+
+/**
  * ice_ptp_set_vernier_wl - Set the window length for vernier calibration
  * @hw: pointer to the HW struct
  *
@@ -686,6 +970,7 @@ static int ice_ptp_set_vernier_wl(struct ice_hw *hw)
  */
 static int ice_ptp_init_phc_e822(struct ice_hw *hw)
 {
+       int err;
        u32 regval;
 
        /* Enable reading switch and PHY registers over the sideband queue */
@@ -696,6 +981,11 @@ static int ice_ptp_init_phc_e822(struct ice_hw *hw)
                   PF_SB_REM_DEV_CTL_PHY0);
        wr32(hw, PF_SB_REM_DEV_CTL, regval);
 
+       /* Initialize the Clock Generation Unit */
+       err = ice_init_cgu_e822(hw);
+       if (err)
+               return err;
+
        /* Set window length for all the ports */
        return ice_ptp_set_vernier_wl(hw);
 }
index 2b6613a..70b1aff 100644 (file)
@@ -92,6 +92,26 @@ struct ice_vernier_info_e822 {
        u32 rx_fixed_delay;
 };
 
+/**
+ * struct ice_cgu_pll_params_e822
+ * @refclk_pre_div: Reference clock pre-divisor
+ * @feedback_div: Feedback divisor
+ * @frac_n_div: Fractional divisor
+ * @post_pll_div: Post PLL divisor
+ *
+ * Clock Generation Unit parameters used to program the PLL based on the
+ * selected TIME_REF frequency.
+ */
+struct ice_cgu_pll_params_e822 {
+       u32 refclk_pre_div;
+       u32 feedback_div;
+       u32 frac_n_div;
+       u32 post_pll_div;
+};
+
+extern const struct
+ice_cgu_pll_params_e822 e822_cgu_params[NUM_ICE_TIME_REF_FREQ];
+
 /* Table of constants related to possible TIME_REF sources */
 extern const struct ice_time_ref_info_e822 e822_time_ref[NUM_ICE_TIME_REF_FREQ];