Add a soc bus driver to print chip model and revision details.
Revisions from downstream drivers/soc/realtek/rtd{119x,129x}/rtk_chip.c.
Signed-off-by: Andreas Färber <afaer...@suse.de>
---
v1 -> v2:
* Added entry to MAINTAINERS
* Changed chip_id and chip_rev from u32 to u16, based on reg field definitions
* Added error return path for get_name for deferred probing, reordered code
MAINTAINERS | 1 +
drivers/soc/Kconfig | 1 +
drivers/soc/Makefile | 1 +
drivers/soc/realtek/Kconfig | 13 +++
drivers/soc/realtek/Makefile | 2 +
drivers/soc/realtek/chip.c | 181 +++++++++++++++++++++++++++++++++++
6 files changed, 199 insertions(+)
create mode 100644 drivers/soc/realtek/Kconfig
create mode 100644 drivers/soc/realtek/Makefile
create mode 100644 drivers/soc/realtek/chip.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 78adbc3cc101..ff0ee48fee6f 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2311,6 +2311,7 @@ F: Documentation/devicetree/bindings/soc/realtek/
F: arch/arm/boot/dts/rtd*
F: arch/arm/mach-realtek/
F: arch/arm64/boot/dts/realtek/
+F: drivers/soc/realtek/
ARM/RENESAS ARM64 ARCHITECTURE
M: Geert Uytterhoeven <geert+rene...@glider.be>
diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig
index 425ab6f7e375..925647993119 100644
--- a/drivers/soc/Kconfig
+++ b/drivers/soc/Kconfig
@@ -11,6 +11,7 @@ source "drivers/soc/imx/Kconfig"
source "drivers/soc/ixp4xx/Kconfig"
source "drivers/soc/mediatek/Kconfig"
source "drivers/soc/qcom/Kconfig"
+source "drivers/soc/realtek/Kconfig"
source "drivers/soc/renesas/Kconfig"
source "drivers/soc/rockchip/Kconfig"
source "drivers/soc/samsung/Kconfig"
diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile
index 36452bed86ef..cdcf00bbad10 100644
--- a/drivers/soc/Makefile
+++ b/drivers/soc/Makefile
@@ -17,6 +17,7 @@ obj-$(CONFIG_SOC_XWAY) += lantiq/
obj-y += mediatek/
obj-y += amlogic/
obj-y += qcom/
+obj-y += realtek/
obj-y += renesas/
obj-$(CONFIG_ARCH_ROCKCHIP) += rockchip/
obj-$(CONFIG_SOC_SAMSUNG) += samsung/
diff --git a/drivers/soc/realtek/Kconfig b/drivers/soc/realtek/Kconfig
new file mode 100644
index 000000000000..be75c1889c61
--- /dev/null
+++ b/drivers/soc/realtek/Kconfig
@@ -0,0 +1,13 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+if ARCH_REALTEK || COMPILE_TEST
+
+config REALTEK_SOC
+ tristate "Realtek chip info"
+ default ARCH_REALTEK
+ select SOC_BUS
+ help
+ Say 'y' here to enable support for SoC info on Realtek RTD1195 and
+ RTD1295 SoC families.
+ If unsure, say 'n'.
+
+endif
diff --git a/drivers/soc/realtek/Makefile b/drivers/soc/realtek/Makefile
new file mode 100644
index 000000000000..49900273905b
--- /dev/null
+++ b/drivers/soc/realtek/Makefile
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+obj-$(CONFIG_REALTEK_SOC) += chip.o
diff --git a/drivers/soc/realtek/chip.c b/drivers/soc/realtek/chip.c
new file mode 100644
index 000000000000..c4650d512c91
--- /dev/null
+++ b/drivers/soc/realtek/chip.c
@@ -0,0 +1,181 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Realtek Digital Home Center System-on-Chip info
+ *
+ * Copyright (c) 2017-2020 Andreas Färber
+ */
+
+#include <linux/bitfield.h>
+#include <linux/io.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+#include <linux/sys_soc.h>
+
+#define REG_SB2_CHIP_ID 0x200
+#define REG_SB2_CHIP_INFO 0x204
+
+#define SB2_CHIP_ID_CHIP_ID GENMASK(15, 0)
+
+#define SB2_CHIP_INFO_REVISE_ID GENMASK(31, 16)
+
+struct dhc_soc_revision {
+ const char *name;
+ u16 chip_rev;
+};
+
+static const struct dhc_soc_revision rtd1195_revisions[] = {
+ { "A", 0x0000 },
+ { "B", 0x0001 },
+ { "C", 0x0002 },
+ { "D", 0x0003 },
+ { }
+};
+
+static const struct dhc_soc_revision rtd1295_revisions[] = {
+ { "A00", 0x0000 },
+ { "A01", 0x0001 },
+ { "B00", 0x0002 },
+ { "B01", 0x0003 },
+ { }
+};
+
+struct dhc_soc {
+ u16 chip_id;
+ const char *family;
+ const char *(*get_name)(struct device *dev, const struct dhc_soc *s);
+ const struct dhc_soc_revision *revisions;
+ const char *codename;
+};
+
+static const char *default_name(struct device *dev, const struct dhc_soc *s)
+{
+ return s->family;
+}
+
+static const struct dhc_soc dhc_soc_families[] = {
+ { 0x6329, "RTD1195", default_name, rtd1195_revisions, "Phoenix" },
+ { 0x6421, "RTD1295", default_name, rtd1295_revisions, "Kylin" },
+};
+
+static const struct dhc_soc *dhc_soc_by_chip_id(u16 chip_id)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(dhc_soc_families); i++) {
+ const struct dhc_soc *family = &dhc_soc_families[i];
+
+ if (family->chip_id == chip_id)
+ return family;
+ }
+ return NULL;
+}
+
+static const char *dhc_soc_rev(const struct dhc_soc *family, u16 chip_rev)
+{
+ if (family) {
+ const struct dhc_soc_revision *rev = family->revisions;
+
+ while (rev && rev->name) {
+ if (rev->chip_rev == chip_rev)
+ return rev->name;
+ rev++;
+ }
+ }
+ return "unknown";
+}
+
+static int dhc_soc_probe(struct platform_device *pdev)
+{
+ const struct dhc_soc *s;
+ struct soc_device_attribute *soc_dev_attr;
+ struct soc_device *soc_dev;
+ struct device_node *node;
+ struct regmap *regmap;
+ u16 chip_id, chip_rev;
+ unsigned int val;
+ int ret;
+
+ regmap = syscon_node_to_regmap(pdev->dev.of_node->parent);
+ if (IS_ERR(regmap))
+ return PTR_ERR(regmap);
+
+ ret = regmap_read(regmap, REG_SB2_CHIP_ID, &val);
+ if (ret)
+ return ret;
+ chip_id = FIELD_GET(SB2_CHIP_ID_CHIP_ID, val);
+
+ ret = regmap_read(regmap, REG_SB2_CHIP_INFO, &val);
+ if (ret)
+ return ret;
+ chip_rev = FIELD_GET(SB2_CHIP_INFO_REVISE_ID, val);
+
+ soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
+ if (!soc_dev_attr)
+ return -ENOMEM;
+
+ node = of_find_node_by_path("/");
+ of_property_read_string(node, "model", &soc_dev_attr->machine);
+ of_node_put(node);
+
+ s = dhc_soc_by_chip_id(chip_id);
+
+ if (likely(s && s->get_name)) {
+ soc_dev_attr->soc_id = s->get_name(&pdev->dev, s);
+ if (IS_ERR(soc_dev_attr->soc_id))
+ return PTR_ERR(soc_dev_attr->soc_id);
+ } else
+ soc_dev_attr->soc_id = "unknown";
+
+ soc_dev_attr->revision = dhc_soc_rev(s, chip_rev);
+
+ soc_dev_attr->family = kasprintf(GFP_KERNEL, "Realtek %s",
+ (s && s->codename) ? s->codename :
+ ((s && s->family) ? s->family : "Digital Home Center"));
+
+ soc_dev = soc_device_register(soc_dev_attr);
+ if (IS_ERR(soc_dev)) {
+ kfree(soc_dev_attr->family);
+ kfree(soc_dev_attr);
+ return PTR_ERR(soc_dev);
+ }
+
+ platform_set_drvdata(pdev, soc_dev);
+
+ pr_info("%s %s (0x%04x) rev %s (0x%04x) detected\n",
+ soc_dev_attr->family, soc_dev_attr->soc_id, (u32)chip_id,
+ soc_dev_attr->revision, (u32)chip_rev);
+
+ return 0;
+}
+
+static int dhc_soc_remove(struct platform_device *pdev)
+{
+ struct soc_device *soc_dev = platform_get_drvdata(pdev);
+
+ soc_device_unregister(soc_dev);
+
+ return 0;
+}
+
+static const struct of_device_id dhc_soc_dt_ids[] = {
+ { .compatible = "realtek,rtd1195-chip" },
+ { }
+};
+
+static struct platform_driver dhc_soc_driver = {
+ .probe = dhc_soc_probe,
+ .remove = dhc_soc_remove,
+ .driver = {
+ .name = "dhc-soc",
+ .of_match_table = dhc_soc_dt_ids,
+ },
+};
+module_platform_driver(dhc_soc_driver);
+
+MODULE_DESCRIPTION("Realtek DHC SoC identification driver");
+MODULE_LICENSE("GPL");
--
2.26.2
