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path: root/drivers/soc/loongson/loongson2_guts.c
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Diffstat (limited to 'drivers/soc/loongson/loongson2_guts.c')
-rw-r--r--drivers/soc/loongson/loongson2_guts.c192
1 files changed, 192 insertions, 0 deletions
diff --git a/drivers/soc/loongson/loongson2_guts.c b/drivers/soc/loongson/loongson2_guts.c
new file mode 100644
index 000000000000..bace4bc8e03b
--- /dev/null
+++ b/drivers/soc/loongson/loongson2_guts.c
@@ -0,0 +1,192 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Author: Yinbo Zhu <zhuyinbo@loongson.cn>
+ * Copyright (C) 2022-2023 Loongson Technology Corporation Limited
+ */
+
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/of_fdt.h>
+#include <linux/sys_soc.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+
+static struct soc_device_attribute soc_dev_attr;
+static struct soc_device *soc_dev;
+
+/*
+ * Global Utility Registers.
+ *
+ * Not all registers defined in this structure are available on all chips, so
+ * you are expected to know whether a given register actually exists on your
+ * chip before you access it.
+ *
+ * Also, some registers are similar on different chips but have slightly
+ * different names. In these cases, one name is chosen to avoid extraneous
+ * #ifdefs.
+ */
+struct scfg_guts {
+ u32 svr; /* Version Register */
+ u8 res0[4];
+ u16 feature; /* Feature Register */
+ u32 vendor; /* Vendor Register */
+ u8 res1[6];
+ u32 id;
+ u8 res2[0x3ff8 - 0x18];
+ u32 chip;
+};
+
+static struct guts {
+ struct scfg_guts __iomem *regs;
+ bool little_endian;
+} *guts;
+
+struct loongson2_soc_die_attr {
+ char *die;
+ u32 svr;
+ u32 mask;
+};
+
+/* SoC die attribute definition for Loongson-2 platform */
+static const struct loongson2_soc_die_attr loongson2_soc_die[] = {
+
+ /*
+ * LoongArch-based SoCs Loongson-2 Series
+ */
+
+ /* Die: 2k1000, SoC: 2k1000 */
+ { .die = "2K1000",
+ .svr = 0x00000013,
+ .mask = 0x000000ff,
+ },
+ { },
+};
+
+static const struct loongson2_soc_die_attr *loongson2_soc_die_match(
+ u32 svr, const struct loongson2_soc_die_attr *matches)
+{
+ while (matches->svr) {
+ if (matches->svr == (svr & matches->mask))
+ return matches;
+ matches++;
+ };
+
+ return NULL;
+}
+
+static u32 loongson2_guts_get_svr(void)
+{
+ u32 svr = 0;
+
+ if (!guts || !guts->regs)
+ return svr;
+
+ if (guts->little_endian)
+ svr = ioread32(&guts->regs->svr);
+ else
+ svr = ioread32be(&guts->regs->svr);
+
+ return svr;
+}
+
+static int loongson2_guts_probe(struct platform_device *pdev)
+{
+ struct device_node *root, *np = pdev->dev.of_node;
+ struct device *dev = &pdev->dev;
+ struct resource *res;
+ const struct loongson2_soc_die_attr *soc_die;
+ const char *machine;
+ u32 svr;
+
+ /* Initialize guts */
+ guts = devm_kzalloc(dev, sizeof(*guts), GFP_KERNEL);
+ if (!guts)
+ return -ENOMEM;
+
+ guts->little_endian = of_property_read_bool(np, "little-endian");
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ guts->regs = ioremap(res->start, res->end - res->start + 1);
+ if (IS_ERR(guts->regs))
+ return PTR_ERR(guts->regs);
+
+ /* Register soc device */
+ root = of_find_node_by_path("/");
+ if (of_property_read_string(root, "model", &machine))
+ of_property_read_string_index(root, "compatible", 0, &machine);
+ of_node_put(root);
+ if (machine)
+ soc_dev_attr.machine = devm_kstrdup(dev, machine, GFP_KERNEL);
+
+ svr = loongson2_guts_get_svr();
+ soc_die = loongson2_soc_die_match(svr, loongson2_soc_die);
+ if (soc_die) {
+ soc_dev_attr.family = devm_kasprintf(dev, GFP_KERNEL,
+ "Loongson %s", soc_die->die);
+ } else {
+ soc_dev_attr.family = devm_kasprintf(dev, GFP_KERNEL, "Loongson");
+ }
+ if (!soc_dev_attr.family)
+ return -ENOMEM;
+ soc_dev_attr.soc_id = devm_kasprintf(dev, GFP_KERNEL,
+ "svr:0x%08x", svr);
+ if (!soc_dev_attr.soc_id)
+ return -ENOMEM;
+ soc_dev_attr.revision = devm_kasprintf(dev, GFP_KERNEL, "%d.%d",
+ (svr >> 4) & 0xf, svr & 0xf);
+ if (!soc_dev_attr.revision)
+ return -ENOMEM;
+
+ soc_dev = soc_device_register(&soc_dev_attr);
+ if (IS_ERR(soc_dev))
+ return PTR_ERR(soc_dev);
+
+ pr_info("Machine: %s\n", soc_dev_attr.machine);
+ pr_info("SoC family: %s\n", soc_dev_attr.family);
+ pr_info("SoC ID: %s, Revision: %s\n",
+ soc_dev_attr.soc_id, soc_dev_attr.revision);
+
+ return 0;
+}
+
+static int loongson2_guts_remove(struct platform_device *dev)
+{
+ soc_device_unregister(soc_dev);
+
+ return 0;
+}
+
+/*
+ * Table for matching compatible strings, for device tree
+ * guts node, for Loongson-2 SoCs.
+ */
+static const struct of_device_id loongson2_guts_of_match[] = {
+ { .compatible = "loongson,ls2k-chipid", },
+ {}
+};
+MODULE_DEVICE_TABLE(of, loongson2_guts_of_match);
+
+static struct platform_driver loongson2_guts_driver = {
+ .driver = {
+ .name = "loongson2-guts",
+ .of_match_table = loongson2_guts_of_match,
+ },
+ .probe = loongson2_guts_probe,
+ .remove = loongson2_guts_remove,
+};
+
+static int __init loongson2_guts_init(void)
+{
+ return platform_driver_register(&loongson2_guts_driver);
+}
+core_initcall(loongson2_guts_init);
+
+static void __exit loongson2_guts_exit(void)
+{
+ platform_driver_unregister(&loongson2_guts_driver);
+}
+module_exit(loongson2_guts_exit);
+
+MODULE_DESCRIPTION("Loongson2 GUTS driver");
+MODULE_LICENSE("GPL");