soc: ti: add k3 platforms chipid module driver

The Texas Instruments K3 Multicore SoC platforms have chipid module which
is represented by CTRLMMR_xxx_JTAGID register and contains information
about SoC id and revision.
 Bits:
  31-28 VARIANT Device variant
  27-12 PARTNO  Part number
  11-1  MFG     Indicates TI as manufacturer (0x17)
  1             Always 1

This patch adds corresponding driver to identify the TI K3 SoC family and
revision, and registers this information with the SoC bus. It is available
under /sys/devices/soc0/ for user space, and can be checked, where needed,
in Kernel using soc_device_match().

Identification is done by:
- checking MFG to be TI ID
 - retrieving Device variant (revision)
 - retrieving Part number and convert it to the family
 - retrieving machine from DT "/model"

Example J721E:
  # cat /sys/devices/soc0/{machine,family,revision}
  Texas Instruments K3 J721E SoC
  J721E
  SR1.0

Example AM65x:
  # cat /sys/devices/soc0/{machine,family,revision}
  Texas Instruments AM654 Base Board
  AM65X
  SR1.0

Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Reviewed-by: Lokesh Vutla <lokeshvutla@ti.com>
Reviewed-by: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>

diff --git a/drivers/soc/ti/Kconfig b/drivers/soc/ti/Kconfig
index 4486e05..e192fb7 100644 (file)
--- a/drivers/soc/ti/Kconfig
+++ b/drivers/soc/ti/Kconfig
@@ -91,6 +91,16 @@ config TI_K3_RINGACC
          and a consumer. There is one RINGACC module per NAVSS on TI AM65x SoCs
          If unsure, say N.
 
+config TI_K3_SOCINFO
+       bool
+       depends on ARCH_K3 || COMPILE_TEST
+       select SOC_BUS
+       select MFD_SYSCON
+       help
+         Include support for the SoC bus socinfo for the TI K3 Multicore SoC
+         platforms to provide information about the SoC family and
+         variant to user space.
+
 endif # SOC_TI
 
 config TI_SCI_INTA_MSI_DOMAIN

diff --git a/drivers/soc/ti/Makefile b/drivers/soc/ti/Makefile
index bec8279..1110e5c 100644 (file)
--- a/drivers/soc/ti/Makefile
+++ b/drivers/soc/ti/Makefile
@@ -11,3 +11,4 @@ obj-$(CONFIG_WKUP_M3_IPC)             += wkup_m3_ipc.o
 obj-$(CONFIG_TI_SCI_PM_DOMAINS)                += ti_sci_pm_domains.o
 obj-$(CONFIG_TI_SCI_INTA_MSI_DOMAIN)   += ti_sci_inta_msi.o
 obj-$(CONFIG_TI_K3_RINGACC)            += k3-ringacc.o
+obj-$(CONFIG_TI_K3_SOCINFO)            += k3-socinfo.o

diff --git a/drivers/soc/ti/k3-socinfo.c b/drivers/soc/ti/k3-socinfo.c
new file mode 100644 (file)
index 0000000..af0ba52
--- /dev/null
+++ b/drivers/soc/ti/k3-socinfo.c
@@ -0,0 +1,152 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * TI K3 SoC info driver
+ *
+ * Copyright (C) 2020 Texas Instruments Incorporated - http://www.ti.com
+ */
+
+#include <linux/mfd/syscon.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/regmap.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/sys_soc.h>
+
+#define CTRLMMR_WKUP_JTAGID_REG                0
+/*
+ * Bits:
+ *  31-28 VARIANT      Device variant
+ *  27-12 PARTNO       Part number
+ *  11-1  MFG          Indicates TI as manufacturer (0x17)
+ *  1                  Always 1
+ */
+#define CTRLMMR_WKUP_JTAGID_VARIANT_SHIFT      (28)
+#define CTRLMMR_WKUP_JTAGID_VARIANT_MASK       GENMASK(31, 28)
+
+#define CTRLMMR_WKUP_JTAGID_PARTNO_SHIFT       (12)
+#define CTRLMMR_WKUP_JTAGID_PARTNO_MASK                GENMASK(27, 12)
+
+#define CTRLMMR_WKUP_JTAGID_MFG_SHIFT          (1)
+#define CTRLMMR_WKUP_JTAGID_MFG_MASK           GENMASK(11, 1)
+
+#define CTRLMMR_WKUP_JTAGID_MFG_TI             0x17
+
+static const struct k3_soc_id {
+       unsigned int id;
+       const char *family_name;
+} k3_soc_ids[] = {
+       { 0xBB5A, "AM65X" },
+       { 0xBB64, "J721E" },
+};
+
+static int
+k3_chipinfo_partno_to_names(unsigned int partno,
+                           struct soc_device_attribute *soc_dev_attr)
+{
+       int i;
+
+       for (i = 0; i < ARRAY_SIZE(k3_soc_ids); i++)
+               if (partno == k3_soc_ids[i].id) {
+                       soc_dev_attr->family = k3_soc_ids[i].family_name;
+                       return 0;
+               }
+
+       return -EINVAL;
+}
+
+static int k3_chipinfo_probe(struct platform_device *pdev)
+{
+       struct device_node *node = pdev->dev.of_node;
+       struct soc_device_attribute *soc_dev_attr;
+       struct device *dev = &pdev->dev;
+       struct soc_device *soc_dev;
+       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;
+
+       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;
+       variant++;
+
+       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;
+
+       soc_dev_attr->revision = kasprintf(GFP_KERNEL, "SR%x.0", variant);
+       if (!soc_dev_attr->revision) {
+               ret = -ENOMEM;
+               goto err;
+       }
+
+       ret = k3_chipinfo_partno_to_names(partno_id, soc_dev_attr);
+       if (ret) {
+               dev_err(dev, "Unknown SoC JTAGID[0x%08X]\n", jtag_id);
+               ret = -ENODEV;
+               goto err_free_rev;
+       }
+
+       node = of_find_node_by_path("/");
+       of_property_read_string(node, "model", &soc_dev_attr->machine);
+       of_node_put(node);
+
+       soc_dev = soc_device_register(soc_dev_attr);
+       if (IS_ERR(soc_dev)) {
+               ret = PTR_ERR(soc_dev);
+               goto err_free_rev;
+       }
+
+       dev_info(dev, "Family:%s rev:%s JTAGID[0x%08x] Detected\n",
+                soc_dev_attr->family,
+                soc_dev_attr->revision, jtag_id);
+
+       return 0;
+
+err_free_rev:
+       kfree(soc_dev_attr->revision);
+err:
+       kfree(soc_dev_attr);
+       return ret;
+}
+
+static const struct of_device_id k3_chipinfo_of_match[] = {
+       { .compatible = "ti,am654-chipid", },
+       { /* sentinel */ },
+};
+
+static struct platform_driver k3_chipinfo_driver = {
+       .driver = {
+               .name = "k3-chipinfo",
+               .of_match_table = k3_chipinfo_of_match,
+       },
+       .probe = k3_chipinfo_probe,
+};
+
+static int __init k3_chipinfo_init(void)
+{
+       return platform_driver_register(&k3_chipinfo_driver);
+}
+subsys_initcall(k3_chipinfo_init);