[PATCH 3/4] soc: ti: k3-socinfo: Add support for nvmem cells

[Markus Schneider-Pargmann]

Support nvmem cells to retrieve chip variant, part number and
manufacturer. As multiple different devices depend on these information
it is cleaner to abstract efuse fields with nvmem cells.

If chipvariant nvmem cell is found, the driver assumes nvmem cells are
being used and tries to find the other fields as well. If it can't find
'chipvariant' it will try to create a regmap.

Some prints had to be updated as I don't read the full jtagid anymore.

Signed-off-by: Markus Schneider-Pargmann <msp at baylibre.com>
Acked-by: Andrew Davis <afd at ti.com>
---
 drivers/soc/ti/k3-socinfo.c | 67 +++++++++++++++++++++++++------------
 1 file changed, 46 insertions(+), 21 deletions(-)

diff --git a/drivers/soc/ti/k3-socinfo.c b/drivers/soc/ti/k3-socinfo.c
index 59101bf7cf23..99794aeb6206 100644
--- a/drivers/soc/ti/k3-socinfo.c
+++ b/drivers/soc/ti/k3-socinfo.c
@@ -6,6 +6,7 @@
  */
 
 #include <linux/mfd/syscon.h>
+#include <linux/nvmem-consumer.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
 #include <linux/regmap.h>
@@ -114,45 +115,68 @@ static int k3_chipinfo_probe(struct platform_device *pdev)
 	struct regmap *regmap;
 	u32 partno_id;
 	u32 variant;
-	u32 jtag_id;
 	u32 mfg;
 	int ret;
 
-	regmap = device_node_to_regmap(node);
-	if (IS_ERR(regmap))
-		return PTR_ERR(regmap);
-
-	ret = regmap_read(regmap, CTRLMMR_WKUP_JTAGID_REG, &jtag_id);
-	if (ret < 0)
-		return ret;
-
-	mfg = (jtag_id & CTRLMMR_WKUP_JTAGID_MFG_MASK) >>
-	       CTRLMMR_WKUP_JTAGID_MFG_SHIFT;
+	ret = nvmem_cell_read_u32(dev, "chipvariant", &variant);
+	if (ret && ret != -ENOENT)
+		return dev_err_probe(dev, ret,
+				     "Failed to read nvmem cell 'chipvariant': %pe",
+				     ERR_PTR(ret));
+
+	if (ret != -ENOENT) {
+		ret = nvmem_cell_read_u32(dev, "chippartno", &partno_id);
+		if (ret)
+			return dev_err_probe(dev, ret,
+					     "Failed to read nvmem cell 'chippartno': %pe",
+					     ERR_PTR(ret));
+
+		ret = nvmem_cell_read_u32(dev, "chipmanufacturer", &mfg);
+		if (ret)
+			return dev_err_probe(dev, ret,
+					     "Failed to read nvmem cell 'chipmanufacturer': %pe",
+					     ERR_PTR(ret));
+	} else {
+		u32 jtag_id;
+
+		regmap = device_node_to_regmap(node);
+		if (IS_ERR(regmap))
+			return PTR_ERR(regmap);
+
+		ret = regmap_read(regmap, CTRLMMR_WKUP_JTAGID_REG, &jtag_id);
+		if (ret < 0)
+			return ret;
+
+		mfg = (jtag_id & CTRLMMR_WKUP_JTAGID_MFG_MASK) >>
+		       CTRLMMR_WKUP_JTAGID_MFG_SHIFT;
+
+		variant = (jtag_id & CTRLMMR_WKUP_JTAGID_VARIANT_MASK) >>
+			  CTRLMMR_WKUP_JTAGID_VARIANT_SHIFT;
+
+		partno_id = (jtag_id & CTRLMMR_WKUP_JTAGID_PARTNO_MASK) >>
+			 CTRLMMR_WKUP_JTAGID_PARTNO_SHIFT;
+	}
 
 	if (mfg != CTRLMMR_WKUP_JTAGID_MFG_TI) {
 		dev_err(dev, "Invalid MFG SoC\n");
 		return -ENODEV;
 	}
 
-	variant = (jtag_id & CTRLMMR_WKUP_JTAGID_VARIANT_MASK) >>
-		  CTRLMMR_WKUP_JTAGID_VARIANT_SHIFT;
-
-	partno_id = (jtag_id & CTRLMMR_WKUP_JTAGID_PARTNO_MASK) >>
-		 CTRLMMR_WKUP_JTAGID_PARTNO_SHIFT;
-
 	soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
 	if (!soc_dev_attr)
 		return -ENOMEM;
 
 	ret = k3_chipinfo_partno_to_names(partno_id, soc_dev_attr);
 	if (ret) {
-		dev_err(dev, "Unknown SoC JTAGID[0x%08X]: %d\n", jtag_id, ret);
+		dev_err(dev, "Unknown SoC JTAGID[variant=0x%X, partno=0x%X]: %d\n",
+			variant, partno_id, ret);
 		goto err;
 	}
 
 	ret = k3_chipinfo_variant_to_sr(partno_id, variant, soc_dev_attr);
 	if (ret) {
-		dev_err(dev, "Unknown SoC SR[0x%08X]: %d\n", jtag_id, ret);
+		dev_err(dev, "Unknown SoC SR[variant=0x%X, partno=0x%X]: %d\n",
+			variant, partno_id, ret);
 		goto err;
 	}
 
@@ -166,9 +190,10 @@ static int k3_chipinfo_probe(struct platform_device *pdev)
 		goto err_free_rev;
 	}
 
-	dev_info(dev, "Family:%s rev:%s JTAGID[0x%08x] Detected\n",
+	dev_info(dev, "Family:%s rev:%s JTAGID[variant=0x%X, partno=0x%X] Detected\n",
 		 soc_dev_attr->family,
-		 soc_dev_attr->revision, jtag_id);
+		 soc_dev_attr->revision,
+		 variant, partno_id);
 
 	return 0;
 
-- 
2.43.0