[PATCH] thermal: intel: int340x: Read DDR data rate for Nova Lake

[Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>]

Add support for reading DDR data rate from PCI config offset.
The register details are:
CFG Offset : 0xE0
Bits	   : 11:2

DDR Data rate is in 33.33 MTPS units.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
---
 .../int340x_thermal/processor_thermal_rfim.c     | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/drivers/thermal/intel/int340x_thermal/processor_thermal_rfim.c b/drivers/thermal/intel/int340x_thermal/processor_thermal_rfim.c
index 314fbc1f490f..2e834a175471 100644
--- a/drivers/thermal/intel/int340x_thermal/processor_thermal_rfim.c
+++ b/drivers/thermal/intel/int340x_thermal/processor_thermal_rfim.c
@@ -402,6 +402,11 @@ static ssize_t rfi_restriction_show(struct device *dev,
 	return sysfs_emit(buf, "%llu\n", resp);
 }
 
+ /* ddr_data_rate */
+static const struct mmio_reg nvl_ddr_data_rate_reg = { 1, 0xE0, 10, 0x3FF, 2};
+
+static const struct mmio_reg *ddr_data_rate_reg;
+
 static ssize_t ddr_data_rate_show(struct device *dev,
 				  struct device_attribute *attr,
 				  char *buf)
@@ -410,10 +415,20 @@ static ssize_t ddr_data_rate_show(struct device *dev,
 	u64 resp;
 	int ret;
 
+	if (ddr_data_rate_reg) {
+		u16 reg_val;
+
+		pci_read_config_word(to_pci_dev(dev), ddr_data_rate_reg->offset, &reg_val);
+		resp = (reg_val >> ddr_data_rate_reg->shift) & ddr_data_rate_reg->mask;
+		resp = (resp * 3333) / 100;
+		goto ret_resp;
+	}
+
 	ret = processor_thermal_send_mbox_read_cmd(to_pci_dev(dev), id, &resp);
 	if (ret)
 		return ret;
 
+ret_resp:
 	return sysfs_emit(buf, "%llu\n", resp);
 }
 
@@ -461,6 +476,7 @@ int proc_thermal_rfim_add(struct pci_dev *pdev, struct proc_thermal_device *proc
 		case PCI_DEVICE_ID_INTEL_NVL_H_THERMAL:
 		case PCI_DEVICE_ID_INTEL_NVL_S_THERMAL:
 			dlvr_mmio_regs_table = nvl_dlvr_mmio_regs;
+			ddr_data_rate_reg = &nvl_ddr_data_rate_reg;
 			break;
 		default:
 			dlvr_mmio_regs_table = dlvr_mmio_regs;
-- 
2.52.0