ice: fix crash on probe for DPLL enabled E810 LOM

The E810 Lan On Motherboard (LOM) design is vendor specific. Intel
provides the reference design, but it is up to vendor on the final
product design. For some cases, like Linux DPLL support, the static
values defined in the driver does not reflect the actual LOM design.
Current implementation of dpll pins is causing the crash on probe
of the ice driver for such DPLL enabled E810 LOM designs:

WARNING: (...) at drivers/dpll/dpll_core.c:495 dpll_pin_get+0x2c4/0x330
...
Call Trace:
 <TASK>
 ? __warn+0x83/0x130
 ? dpll_pin_get+0x2c4/0x330
 ? report_bug+0x1b7/0x1d0
 ? handle_bug+0x42/0x70
 ? exc_invalid_op+0x18/0x70
 ? asm_exc_invalid_op+0x1a/0x20
 ? dpll_pin_get+0x117/0x330
 ? dpll_pin_get+0x2c4/0x330
 ? dpll_pin_get+0x117/0x330
 ice_dpll_get_pins.isra.0+0x52/0xe0 [ice]
...

The number of dpll pins enabled by LOM vendor is greater than expected
and defined in the driver for Intel designed NICs, which causes the crash.

Prevent the crash and allow generic pin initialization within Linux DPLL
subsystem for DPLL enabled E810 LOM designs.

Newly designed solution for described issue will be based on "per HW
design" pin initialization. It requires pin information dynamically
acquired from the firmware and is already in progress, planned for
next-tree only.

Fixes: d7999f5ea64b ("ice: implement dpll interface to control cgu")
Reviewed-by: Karol Kolacinski <karol.kolacinski@intel.com>
Signed-off-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com>
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

1 files changed, 70 insertions, 0 deletions

diff --git a/drivers/net/ethernet/intel/ice/ice_dpll.c b/drivers/net/ethernet/intel/ice/ice_dpll.c
index 74c0e7319a4c..d5ad6d84007c 100644
--- a/drivers/net/ethernet/intel/ice/ice_dpll.c
+++ b/drivers/net/ethernet/intel/ice/ice_dpll.c
@@ -10,6 +10,7 @@
 #define ICE_DPLL_PIN_IDX_INVALID		0xff
 #define ICE_DPLL_RCLK_NUM_PER_PF		1
 #define ICE_DPLL_PIN_ESYNC_PULSE_HIGH_PERCENT	25
+#define ICE_DPLL_PIN_GEN_RCLK_FREQ		1953125
 
 /**
  * enum ice_dpll_pin_type - enumerate ice pin types:
@@ -2064,6 +2065,73 @@ static int ice_dpll_init_worker(struct ice_pf *pf)
 }
 
 /**
+ * ice_dpll_init_info_pins_generic - initializes generic pins info
+ * @pf: board private structure
+ * @input: if input pins initialized
+ *
+ * Init information for generic pins, cache them in PF's pins structures.
+ *
+ * Return:
+ * * 0 - success
+ * * negative - init failure reason
+ */
+static int ice_dpll_init_info_pins_generic(struct ice_pf *pf, bool input)
+{
+	struct ice_dpll *de = &pf->dplls.eec, *dp = &pf->dplls.pps;
+	static const char labels[][sizeof("99")] = {
+		"0", "1", "2", "3", "4", "5", "6", "7", "8",
+		"9", "10", "11", "12", "13", "14", "15" };
+	u32 cap = DPLL_PIN_CAPABILITIES_STATE_CAN_CHANGE;
+	enum ice_dpll_pin_type pin_type;
+	int i, pin_num, ret = -EINVAL;
+	struct ice_dpll_pin *pins;
+	u32 phase_adj_max;
+
+	if (input) {
+		pin_num = pf->dplls.num_inputs;
+		pins = pf->dplls.inputs;
+		phase_adj_max = pf->dplls.input_phase_adj_max;
+		pin_type = ICE_DPLL_PIN_TYPE_INPUT;
+		cap |= DPLL_PIN_CAPABILITIES_PRIORITY_CAN_CHANGE;
+	} else {
+		pin_num = pf->dplls.num_outputs;
+		pins = pf->dplls.outputs;
+		phase_adj_max = pf->dplls.output_phase_adj_max;
+		pin_type = ICE_DPLL_PIN_TYPE_OUTPUT;
+	}
+	if (pin_num > ARRAY_SIZE(labels))
+		return ret;
+
+	for (i = 0; i < pin_num; i++) {
+		pins[i].idx = i;
+		pins[i].prop.board_label = labels[i];
+		pins[i].prop.phase_range.min = phase_adj_max;
+		pins[i].prop.phase_range.max = -phase_adj_max;
+		pins[i].prop.capabilities = cap;
+		pins[i].pf = pf;
+		ret = ice_dpll_pin_state_update(pf, &pins[i], pin_type, NULL);
+		if (ret)
+			break;
+		if (input && pins[i].freq == ICE_DPLL_PIN_GEN_RCLK_FREQ)
+			pins[i].prop.type = DPLL_PIN_TYPE_MUX;
+		else
+			pins[i].prop.type = DPLL_PIN_TYPE_EXT;
+		if (!input)
+			continue;
+		ret = ice_aq_get_cgu_ref_prio(&pf->hw, de->dpll_idx, i,
+					      &de->input_prio[i]);
+		if (ret)
+			break;
+		ret = ice_aq_get_cgu_ref_prio(&pf->hw, dp->dpll_idx, i,
+					      &dp->input_prio[i]);
+		if (ret)
+			break;
+	}
+
+	return ret;
+}
+
+/**
  * ice_dpll_init_info_direct_pins - initializes direct pins info
  * @pf: board private structure
  * @pin_type: type of pins being initialized
@@ -2101,6 +2169,8 @@ ice_dpll_init_info_direct_pins(struct ice_pf *pf,
 	default:
 		return -EINVAL;
 	}
+	if (num_pins != ice_cgu_get_num_pins(hw, input))
+		return ice_dpll_init_info_pins_generic(pf, input);
 
 	for (i = 0; i < num_pins; i++) {
 		caps = 0;